Initial implementation of an elasticsearch indexer in Go

linguist/LICENSE.md

+# Linguist
+
+The Ruby [github-linguist](https://github.com/github/linguist) Gem is a useful
+collection of helpers for language detection. This directory contains
+reimplementations of parts of the functionality of that gem.
+
+The file `languages.go` is programmatically generated from
+[this file](https://github.com/github/linguist/blob/master/lib/linguist/languages.yml).
+
+The following license applies:
+
+Copyright (c) 2017 GitHub, Inc.
+
+Permission is hereby granted, free of charge, to any person
+obtaining a copy of this software and associated documentation
+files (the "Software"), to deal in the Software without
+restriction, including without limitation the rights to use,
+copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.

linguist/generate_languages.go.rb

+require 'net/http'
+require 'yaml'
+
+def array(ary)
+  "[]string{#{ary.map(&:inspect).join(", ")}}"
+end
+
+def bool(value, default)
+  value = default if value.nil?
+  (!!value).inspect
+end
+
+def build_language(name, details)
+  out = []
+
+  out << ["Name",         name.inspect]
+  out << ["Type",         details['type'].inspect       ] if details['type']
+  out << ["Group",        details['group'].inspect      ] if details['group']
+  out << ["Color",        details['color'].inspect      ] if details['color']
+  out << ["Aliases",      array(details['aliases'])     ] if details['aliases']
+  out << ["Extensions",   array(details['extensions'])  ] if details['extensions']
+  out << ["Filenames",    array(details['filenames'])   ] if details['filenames']
+  out << ["Interpreters", array(details['interpreters'])] if details['interpreters']
+  out << ["TmScope",      details['tm_scope'].inspect   ] if details['tm_scope']
+  out << ["AceMode",      details['type'].inspect       ] if details['ace_mode']
+  out << ["LanguageID",   details['language_id']        ] if details['language_id']
+
+  # Two strange booleans
+  out << ["Wrap",         bool(details['wrap'], false)      ]
+  out << ["Searchable",   bool(details['searchable'], true) ]
+
+  max_key = out.map {|k,v| k.size }.max
+  out = out.map do |k, v|
+    "\t\t\t#{k}:#{" " * (max_key - k.size)} #{v},"
+  end
+
+  "\t\t#{name.inspect}: &Language{\n#{out.join("\n")}\n\t\t},\n"
+end
+
+LANGUAGES_YML = URI.parse("https://raw.githubusercontent.com/github/linguist/v4.7.6/lib/linguist/languages.yml")
+
+languages = YAML.load(Net::HTTP.get(LANGUAGES_YML))
+
+f = File.open("languages.go", "w")
+f.puts "package linguist"
+f.puts ""
+f.puts "var ("
+f.puts "\tLanguages = map[string]*Language{"
+languages.each {|name, details| f.puts build_language(name, details) }
+f.puts "\t}"
+f.puts ")"
+f.close

linguist/language.go

+package linguist
+
+import (
+	"path"
+)
+
+// There's no YAML support in the Go stdlib, so use ruby instead.
+// This will create a file `languages.go`, containing the Languages variable
+//go:generate ruby generate_languages.go.rb
+
+type Language struct {
+	Name         string
+	Type         string
+	Group        string
+	Color        string
+	Aliases      []string
+	Extensions   []string
+	Filenames    []string
+	Interpreters []string
+	TmScope      string
+	AceMode      string
+	Wrap         bool
+	Searchable   bool
+}
+
+var (
+	languagesByExtension map[string][]*Language
+	languagesByFilename  map[string][]*Language
+)
+
+func init() {
+	languagesByExtension = make(map[string][]*Language)
+	for _, lang := range Languages {
+		for _, ext := range lang.Extensions {
+			languagesByExtension[ext] = append(languagesByExtension[ext], lang)
+		}
+	}
+
+	languagesByFilename = make(map[string][]*Language)
+	for _, lang := range Languages {
+		for _, filename := range lang.Filenames {
+			languagesByFilename[filename] = append(languagesByFilename[filename], lang)
+		}
+	}
+}
+
+// and returns only the languges present in both A and B
+func and(a, b []*Language) []*Language {
+	var out []*Language
+
+	for _, langA := range a {
+		for _, langB := range b {
+			if langA == langB {
+				out = append(out, langA)
+			}
+		}
+	}
+
+	return out
+}
+
+func DetectLanguageByFilename(filename string) []*Language {
+	return languagesByFilename[path.Base(filename)]
+}
+
+func DetectLanguageByExtension(filename string) []*Language {
+	return languagesByExtension[path.Ext(filename)]
+}
+
+func DetectLanguage(filename string, blob []byte) *Language {
+	// TODO: github-linguist uses a range of strategies not replicated here.
+	// It does the following:
+	//
+	//   * modelines
+	//   * shebangs
+	//   * filename / extension (we have these)
+	//   * heuristics
+	//   * classifier
+
+	byFilename := DetectLanguageByFilename(filename)
+	if len(byFilename) == 1 {
+		return byFilename[0]
+	}
+
+	byExtension := DetectLanguageByExtension(filename)
+	if len(byFilename) > 1 {
+		byExtension = and(byFilename, byExtension)
+	}
+
+	if len(byExtension) > 0 {
+		return byExtension[0]
+	}
+
+	return nil
+}

linguist/language_test.go

+package linguist_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"gitlab.com/gitlab-org/es-git-go/linguist"
+)
+
+func TestCommonLanguagesAreDetectedByExtension(t *testing.T) {
+	type tc struct {
+		filename string
+		name     string
+	}
+
+	for _, tc := range []struct {
+		file string
+		lang string
+	}{
+		{"foo.go", "Go"},
+		{".go", "Go"},
+		{"foo.go.rb", "Ruby"},
+		{"foo.rb", "Ruby"},
+		{"foo.c", "C"},
+		{"foo.cpp", "C++"},
+		{"/bar/foo.ini", "INI"},
+		{"bar/foo.ini", "INI"},
+		{"c:/foo.ini", "INI"},
+		{`c:\foo.ini`, "INI"},
+		{"foo.md", "Markdown"}, // Multiple possible languages
+	} {
+		langs := linguist.DetectLanguageByExtension(tc.file)
+		assert.Equal(t, 1, len(langs))
+		assert.Equal(t, tc.lang, langs[0].Name)
+
+		lang := linguist.DetectLanguage(tc.file, []byte{})
+		assert.NotNil(t, lang)
+		assert.Equal(t, tc.lang, lang.Name)
+
+	}
+}
+
+func TestImaginaryLanguageIsntRecognised(t *testing.T) {
+	lang := linguist.DetectLanguageByFilename("foo.absolutely-nobody-will-make-this-extension")
+	assert.Nil(t, lang)
+}
+
+// This test checks the content of languages.go against expectations chosen to
+// validate the go:generate script
+func TestAttributesAreCopiedCorrectly(t *testing.T) {
+	ada := linguist.Languages["Ada"]
+	assert.NotNil(t, ada)
+
+	cmake := linguist.Languages["CMake"]
+	assert.NotNil(t, cmake)
+
+	gettext := linguist.Languages["Gettext Catalog"]
+	assert.NotNil(t, gettext)
+
+	golang := linguist.Languages["Go"]
+	assert.NotNil(t, golang)
+
+	json := linguist.Languages["JSON"]
+	assert.NotNil(t, json)
+
+	markdown := linguist.Languages["Markdown"]
+	assert.NotNil(t, markdown)
+
+	ruby := linguist.Languages["Ruby"]
+	assert.NotNil(t, ruby)
+
+	assert.Equal(t, "Go", golang.Name)
+	assert.Equal(t, "programming", golang.Type)
+	assert.Equal(t, "JavaScript", json.Group)
+	assert.Equal(t, "#375eab", golang.Color)
+	assert.Equal(t, []string{"ada95", "ada2005"}, ada.Aliases)
+	assert.Equal(t, []string{".go"}, golang.Extensions)
+	assert.Equal(t, []string{"CMakeLists.txt"}, cmake.Filenames)
+	assert.Equal(t, []string{"ruby", "macruby", "rake", "jruby", "rbx"}, ruby.Interpreters)
+	assert.Equal(t, "source.gfm", markdown.TmScope)
+	assert.Equal(t, "programming", golang.AceMode)
+	assert.Equal(t, false, gettext.Searchable)
+	assert.Equal(t, true, markdown.Wrap)
+
+}

main.go

+package main
+
+import (
+	"log"
+	"os"
+
+	"gitlab.com/gitlab-org/es-git-go/elastic"
+	"gitlab.com/gitlab-org/es-git-go/git"
+	"gitlab.com/gitlab-org/es-git-go/indexer"
+)
+
+func main() {
+	if len(os.Args) != 3 {
+		log.Fatalf("Usage: %s <project-id> <project-path>", os.Args[0])
+	}
+
+	projectID := os.Args[1]
+	projectPath := os.Args[2]
+	fromSHA := os.Getenv("FROM_SHA")
+	toSHA := os.Getenv("TO_SHA")
+
+	repo, err := git.NewGoGitRepository(projectPath, fromSHA, toSHA)
+	if err != nil {
+		log.Fatalf("Failed to open %s: %s", projectPath, err)
+	}
+
+	esClient, err := elastic.FromEnv(projectID)
+	if err != nil {
+		log.Fatalln(err)
+	}
+
+	idx := &indexer.Indexer{
+		Submitter:  esClient,
+		Repository: repo,
+	}
+
+	log.Printf("Indexing from %s to %s", repo.FromHash, repo.ToHash)
+	log.Printf("Index: %s, Project ID: %s", esClient.IndexName, esClient.ParentID())
+
+	if err := idx.Index(); err != nil {
+		log.Fatalln("Indexing error: ", err)
+	}
+}

vendor/github.com/aws/aws-sdk-go/LICENSE.txt

+
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+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
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+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
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+      on Your own behalf and on Your sole responsibility, not on behalf
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vendor/github.com/aws/aws-sdk-go/NOTICE.txt

+AWS SDK for Go
+Copyright 2015 Amazon.com, Inc. or its affiliates. All Rights Reserved. 
+Copyright 2014-2015 Stripe, Inc.

vendor/github.com/aws/aws-sdk-go/aws/awserr/error.go

+// Package awserr represents API error interface accessors for the SDK.
+package awserr
+
+// An Error wraps lower level errors with code, message and an original error.
+// The underlying concrete error type may also satisfy other interfaces which
+// can be to used to obtain more specific information about the error.
+//
+// Calling Error() or String() will always include the full information about
+// an error based on its underlying type.
+//
+// Example:
+//
+//     output, err := s3manage.Upload(svc, input, opts)
+//     if err != nil {
+//         if awsErr, ok := err.(awserr.Error); ok {
+//             // Get error details
+//             log.Println("Error:", awsErr.Code(), awsErr.Message())
+//
+//             // Prints out full error message, including original error if there was one.
+//             log.Println("Error:", awsErr.Error())
+//
+//             // Get original error
+//             if origErr := awsErr.OrigErr(); origErr != nil {
+//                 // operate on original error.
+//             }
+//         } else {
+//             fmt.Println(err.Error())
+//         }
+//     }
+//
+type Error interface {
+	// Satisfy the generic error interface.
+	error
+
+	// Returns the short phrase depicting the classification of the error.
+	Code() string
+
+	// Returns the error details message.
+	Message() string
+
+	// Returns the original error if one was set.  Nil is returned if not set.
+	OrigErr() error
+}
+
+// BatchError is a batch of errors which also wraps lower level errors with
+// code, message, and original errors. Calling Error() will include all errors
+// that occurred in the batch.
+//
+// Deprecated: Replaced with BatchedErrors. Only defined for backwards
+// compatibility.
+type BatchError interface {
+	// Satisfy the generic error interface.
+	error
+
+	// Returns the short phrase depicting the classification of the error.
+	Code() string
+
+	// Returns the error details message.
+	Message() string
+
+	// Returns the original error if one was set.  Nil is returned if not set.
+	OrigErrs() []error
+}
+
+// BatchedErrors is a batch of errors which also wraps lower level errors with
+// code, message, and original errors. Calling Error() will include all errors
+// that occurred in the batch.
+//
+// Replaces BatchError
+type BatchedErrors interface {
+	// Satisfy the base Error interface.
+	Error
+
+	// Returns the original error if one was set.  Nil is returned if not set.
+	OrigErrs() []error
+}
+
+// New returns an Error object described by the code, message, and origErr.
+//
+// If origErr satisfies the Error interface it will not be wrapped within a new
+// Error object and will instead be returned.
+func New(code, message string, origErr error) Error {
+	var errs []error
+	if origErr != nil {
+		errs = append(errs, origErr)
+	}
+	return newBaseError(code, message, errs)
+}
+
+// NewBatchError returns an BatchedErrors with a collection of errors as an
+// array of errors.
+func NewBatchError(code, message string, errs []error) BatchedErrors {
+	return newBaseError(code, message, errs)
+}
+
+// A RequestFailure is an interface to extract request failure information from
+// an Error such as the request ID of the failed request returned by a service.
+// RequestFailures may not always have a requestID value if the request failed
+// prior to reaching the service such as a connection error.
+//
+// Example:
+//
+//     output, err := s3manage.Upload(svc, input, opts)
+//     if err != nil {
+//         if reqerr, ok := err.(RequestFailure); ok {
+//             log.Println("Request failed", reqerr.Code(), reqerr.Message(), reqerr.RequestID())
+//         } else {
+//             log.Println("Error:", err.Error())
+//         }
+//     }
+//
+// Combined with awserr.Error:
+//
+//    output, err := s3manage.Upload(svc, input, opts)
+//    if err != nil {
+//        if awsErr, ok := err.(awserr.Error); ok {
+//            // Generic AWS Error with Code, Message, and original error (if any)
+//            fmt.Println(awsErr.Code(), awsErr.Message(), awsErr.OrigErr())
+//
+//            if reqErr, ok := err.(awserr.RequestFailure); ok {
+//                // A service error occurred
+//                fmt.Println(reqErr.StatusCode(), reqErr.RequestID())
+//            }
+//        } else {
+//            fmt.Println(err.Error())
+//        }
+//    }
+//
+type RequestFailure interface {
+	Error
+
+	// The status code of the HTTP response.
+	StatusCode() int
+
+	// The request ID returned by the service for a request failure. This will
+	// be empty if no request ID is available such as the request failed due
+	// to a connection error.
+	RequestID() string
+}
+
+// NewRequestFailure returns a new request error wrapper for the given Error
+// provided.
+func NewRequestFailure(err Error, statusCode int, reqID string) RequestFailure {
+	return newRequestError(err, statusCode, reqID)
+}

vendor/github.com/aws/aws-sdk-go/aws/awserr/types.go

+package awserr
+
+import "fmt"
+
+// SprintError returns a string of the formatted error code.
+//
+// Both extra and origErr are optional.  If they are included their lines
+// will be added, but if they are not included their lines will be ignored.
+func SprintError(code, message, extra string, origErr error) string {
+	msg := fmt.Sprintf("%s: %s", code, message)
+	if extra != "" {
+		msg = fmt.Sprintf("%s\n\t%s", msg, extra)
+	}
+	if origErr != nil {
+		msg = fmt.Sprintf("%s\ncaused by: %s", msg, origErr.Error())
+	}
+	return msg
+}
+
+// A baseError wraps the code and message which defines an error. It also
+// can be used to wrap an original error object.
+//
+// Should be used as the root for errors satisfying the awserr.Error. Also
+// for any error which does not fit into a specific error wrapper type.
+type baseError struct {
+	// Classification of error
+	code string
+
+	// Detailed information about error
+	message string
+
+	// Optional original error this error is based off of. Allows building
+	// chained errors.
+	errs []error
+}
+
+// newBaseError returns an error object for the code, message, and errors.
+//
+// code is a short no whitespace phrase depicting the classification of
+// the error that is being created.
+//
+// message is the free flow string containing detailed information about the
+// error.
+//
+// origErrs is the error objects which will be nested under the new errors to
+// be returned.
+func newBaseError(code, message string, origErrs []error) *baseError {
+	b := &baseError{
+		code:    code,
+		message: message,
+		errs:    origErrs,
+	}
+
+	return b
+}
+
+// Error returns the string representation of the error.
+//
+// See ErrorWithExtra for formatting.
+//
+// Satisfies the error interface.
+func (b baseError) Error() string {
+	size := len(b.errs)
+	if size > 0 {
+		return SprintError(b.code, b.message, "", errorList(b.errs))
+	}
+
+	return SprintError(b.code, b.message, "", nil)
+}
+
+// String returns the string representation of the error.
+// Alias for Error to satisfy the stringer interface.
+func (b baseError) String() string {
+	return b.Error()
+}
+
+// Code returns the short phrase depicting the classification of the error.
+func (b baseError) Code() string {
+	return b.code
+}
+
+// Message returns the error details message.
+func (b baseError) Message() string {
+	return b.message
+}
+
+// OrigErr returns the original error if one was set. Nil is returned if no
+// error was set. This only returns the first element in the list. If the full
+// list is needed, use BatchedErrors.
+func (b baseError) OrigErr() error {
+	switch len(b.errs) {
+	case 0:
+		return nil
+	case 1:
+		return b.errs[0]
+	default:
+		if err, ok := b.errs[0].(Error); ok {
+			return NewBatchError(err.Code(), err.Message(), b.errs[1:])
+		}
+		return NewBatchError("BatchedErrors",
+			"multiple errors occurred", b.errs)
+	}
+}
+
+// OrigErrs returns the original errors if one was set. An empty slice is
+// returned if no error was set.
+func (b baseError) OrigErrs() []error {
+	return b.errs
+}
+
+// So that the Error interface type can be included as an anonymous field
+// in the requestError struct and not conflict with the error.Error() method.
+type awsError Error
+
+// A requestError wraps a request or service error.
+//
+// Composed of baseError for code, message, and original error.
+type requestError struct {
+	awsError
+	statusCode int
+	requestID  string
+}
+
+// newRequestError returns a wrapped error with additional information for
+// request status code, and service requestID.
+//
+// Should be used to wrap all request which involve service requests. Even if
+// the request failed without a service response, but had an HTTP status code
+// that may be meaningful.
+//
+// Also wraps original errors via the baseError.
+func newRequestError(err Error, statusCode int, requestID string) *requestError {
+	return &requestError{
+		awsError:   err,
+		statusCode: statusCode,
+		requestID:  requestID,
+	}
+}
+
+// Error returns the string representation of the error.
+// Satisfies the error interface.
+func (r requestError) Error() string {
+	extra := fmt.Sprintf("status code: %d, request id: %s",
+		r.statusCode, r.requestID)
+	return SprintError(r.Code(), r.Message(), extra, r.OrigErr())
+}
+
+// String returns the string representation of the error.
+// Alias for Error to satisfy the stringer interface.
+func (r requestError) String() string {
+	return r.Error()
+}
+
+// StatusCode returns the wrapped status code for the error
+func (r requestError) StatusCode() int {
+	return r.statusCode
+}
+
+// RequestID returns the wrapped requestID
+func (r requestError) RequestID() string {
+	return r.requestID
+}
+
+// OrigErrs returns the original errors if one was set. An empty slice is
+// returned if no error was set.
+func (r requestError) OrigErrs() []error {
+	if b, ok := r.awsError.(BatchedErrors); ok {
+		return b.OrigErrs()
+	}
+	return []error{r.OrigErr()}
+}
+
+// An error list that satisfies the golang interface
+type errorList []error
+
+// Error returns the string representation of the error.
+//
+// Satisfies the error interface.
+func (e errorList) Error() string {
+	msg := ""
+	// How do we want to handle the array size being zero
+	if size := len(e); size > 0 {
+		for i := 0; i < size; i++ {
+			msg += fmt.Sprintf("%s", e[i].Error())
+			// We check the next index to see if it is within the slice.
+			// If it is, then we append a newline. We do this, because unit tests
+			// could be broken with the additional '\n'
+			if i+1 < size {
+				msg += "\n"
+			}
+		}
+	}
+	return msg
+}

vendor/github.com/aws/aws-sdk-go/aws/awsutil/copy.go

+package awsutil
+
+import (
+	"io"
+	"reflect"
+	"time"
+)
+
+// Copy deeply copies a src structure to dst. Useful for copying request and
+// response structures.
+//
+// Can copy between structs of different type, but will only copy fields which
+// are assignable, and exist in both structs. Fields which are not assignable,
+// or do not exist in both structs are ignored.
+func Copy(dst, src interface{}) {
+	dstval := reflect.ValueOf(dst)
+	if !dstval.IsValid() {
+		panic("Copy dst cannot be nil")
+	}
+
+	rcopy(dstval, reflect.ValueOf(src), true)
+}
+
+// CopyOf returns a copy of src while also allocating the memory for dst.
+// src must be a pointer type or this operation will fail.
+func CopyOf(src interface{}) (dst interface{}) {
+	dsti := reflect.New(reflect.TypeOf(src).Elem())
+	dst = dsti.Interface()
+	rcopy(dsti, reflect.ValueOf(src), true)
+	return
+}
+
+// rcopy performs a recursive copy of values from the source to destination.
+//
+// root is used to skip certain aspects of the copy which are not valid
+// for the root node of a object.
+func rcopy(dst, src reflect.Value, root bool) {
+	if !src.IsValid() {
+		return
+	}
+
+	switch src.Kind() {
+	case reflect.Ptr:
+		if _, ok := src.Interface().(io.Reader); ok {
+			if dst.Kind() == reflect.Ptr && dst.Elem().CanSet() {
+				dst.Elem().Set(src)
+			} else if dst.CanSet() {
+				dst.Set(src)
+			}
+		} else {
+			e := src.Type().Elem()
+			if dst.CanSet() && !src.IsNil() {
+				if _, ok := src.Interface().(*time.Time); !ok {
+					dst.Set(reflect.New(e))
+				} else {
+					tempValue := reflect.New(e)
+					tempValue.Elem().Set(src.Elem())
+					// Sets time.Time's unexported values
+					dst.Set(tempValue)
+				}
+			}
+			if src.Elem().IsValid() {
+				// Keep the current root state since the depth hasn't changed
+				rcopy(dst.Elem(), src.Elem(), root)
+			}
+		}
+	case reflect.Struct:
+		t := dst.Type()
+		for i := 0; i < t.NumField(); i++ {
+			name := t.Field(i).Name
+			srcVal := src.FieldByName(name)
+			dstVal := dst.FieldByName(name)
+			if srcVal.IsValid() && dstVal.CanSet() {
+				rcopy(dstVal, srcVal, false)
+			}
+		}
+	case reflect.Slice:
+		if src.IsNil() {
+			break
+		}
+
+		s := reflect.MakeSlice(src.Type(), src.Len(), src.Cap())
+		dst.Set(s)
+		for i := 0; i < src.Len(); i++ {
+			rcopy(dst.Index(i), src.Index(i), false)
+		}
+	case reflect.Map:
+		if src.IsNil() {
+			break
+		}
+
+		s := reflect.MakeMap(src.Type())
+		dst.Set(s)
+		for _, k := range src.MapKeys() {
+			v := src.MapIndex(k)
+			v2 := reflect.New(v.Type()).Elem()
+			rcopy(v2, v, false)
+			dst.SetMapIndex(k, v2)
+		}
+	default:
+		// Assign the value if possible. If its not assignable, the value would
+		// need to be converted and the impact of that may be unexpected, or is
+		// not compatible with the dst type.
+		if src.Type().AssignableTo(dst.Type()) {
+			dst.Set(src)
+		}
+	}
+}

vendor/github.com/aws/aws-sdk-go/aws/awsutil/equal.go

+package awsutil
+
+import (
+	"reflect"
+)
+
+// DeepEqual returns if the two values are deeply equal like reflect.DeepEqual.
+// In addition to this, this method will also dereference the input values if
+// possible so the DeepEqual performed will not fail if one parameter is a
+// pointer and the other is not.
+//
+// DeepEqual will not perform indirection of nested values of the input parameters.
+func DeepEqual(a, b interface{}) bool {
+	ra := reflect.Indirect(reflect.ValueOf(a))
+	rb := reflect.Indirect(reflect.ValueOf(b))
+
+	if raValid, rbValid := ra.IsValid(), rb.IsValid(); !raValid && !rbValid {
+		// If the elements are both nil, and of the same type the are equal
+		// If they are of different types they are not equal
+		return reflect.TypeOf(a) == reflect.TypeOf(b)
+	} else if raValid != rbValid {
+		// Both values must be valid to be equal
+		return false
+	}
+
+	return reflect.DeepEqual(ra.Interface(), rb.Interface())
+}

vendor/github.com/aws/aws-sdk-go/aws/awsutil/path_value.go

+package awsutil
+
+import (
+	"reflect"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"github.com/jmespath/go-jmespath"
+)
+
+var indexRe = regexp.MustCompile(`(.+)\[(-?\d+)?\]$`)
+
+// rValuesAtPath returns a slice of values found in value v. The values
+// in v are explored recursively so all nested values are collected.
+func rValuesAtPath(v interface{}, path string, createPath, caseSensitive, nilTerm bool) []reflect.Value {
+	pathparts := strings.Split(path, "||")
+	if len(pathparts) > 1 {
+		for _, pathpart := range pathparts {
+			vals := rValuesAtPath(v, pathpart, createPath, caseSensitive, nilTerm)
+			if len(vals) > 0 {
+				return vals
+			}
+		}
+		return nil
+	}
+
+	values := []reflect.Value{reflect.Indirect(reflect.ValueOf(v))}
+	components := strings.Split(path, ".")
+	for len(values) > 0 && len(components) > 0 {
+		var index *int64
+		var indexStar bool
+		c := strings.TrimSpace(components[0])
+		if c == "" { // no actual component, illegal syntax
+			return nil
+		} else if caseSensitive && c != "*" && strings.ToLower(c[0:1]) == c[0:1] {
+			// TODO normalize case for user
+			return nil // don't support unexported fields
+		}
+
+		// parse this component
+		if m := indexRe.FindStringSubmatch(c); m != nil {
+			c = m[1]
+			if m[2] == "" {
+				index = nil
+				indexStar = true
+			} else {
+				i, _ := strconv.ParseInt(m[2], 10, 32)
+				index = &i
+				indexStar = false
+			}
+		}
+
+		nextvals := []reflect.Value{}
+		for _, value := range values {
+			// pull component name out of struct member
+			if value.Kind() != reflect.Struct {
+				continue
+			}
+
+			if c == "*" { // pull all members
+				for i := 0; i < value.NumField(); i++ {
+					if f := reflect.Indirect(value.Field(i)); f.IsValid() {
+						nextvals = append(nextvals, f)
+					}
+				}
+				continue
+			}
+
+			value = value.FieldByNameFunc(func(name string) bool {
+				if c == name {
+					return true
+				} else if !caseSensitive && strings.ToLower(name) == strings.ToLower(c) {
+					return true
+				}
+				return false
+			})
+
+			if nilTerm && value.Kind() == reflect.Ptr && len(components[1:]) == 0 {
+				if !value.IsNil() {
+					value.Set(reflect.Zero(value.Type()))
+				}
+				return []reflect.Value{value}
+			}
+
+			if createPath && value.Kind() == reflect.Ptr && value.IsNil() {
+				// TODO if the value is the terminus it should not be created
+				// if the value to be set to its position is nil.
+				value.Set(reflect.New(value.Type().Elem()))
+				value = value.Elem()
+			} else {
+				value = reflect.Indirect(value)
+			}
+
+			if value.Kind() == reflect.Slice || value.Kind() == reflect.Map {
+				if !createPath && value.IsNil() {
+					value = reflect.ValueOf(nil)
+				}
+			}
+
+			if value.IsValid() {
+				nextvals = append(nextvals, value)
+			}
+		}
+		values = nextvals
+
+		if indexStar || index != nil {
+			nextvals = []reflect.Value{}
+			for _, valItem := range values {
+				value := reflect.Indirect(valItem)
+				if value.Kind() != reflect.Slice {
+					continue
+				}
+
+				if indexStar { // grab all indices
+					for i := 0; i < value.Len(); i++ {
+						idx := reflect.Indirect(value.Index(i))
+						if idx.IsValid() {
+							nextvals = append(nextvals, idx)
+						}
+					}
+					continue
+				}
+
+				// pull out index
+				i := int(*index)
+				if i >= value.Len() { // check out of bounds
+					if createPath {
+						// TODO resize slice
+					} else {
+						continue
+					}
+				} else if i < 0 { // support negative indexing
+					i = value.Len() + i
+				}
+				value = reflect.Indirect(value.Index(i))
+
+				if value.Kind() == reflect.Slice || value.Kind() == reflect.Map {
+					if !createPath && value.IsNil() {
+						value = reflect.ValueOf(nil)
+					}
+				}
+
+				if value.IsValid() {
+					nextvals = append(nextvals, value)
+				}
+			}
+			values = nextvals
+		}
+
+		components = components[1:]
+	}
+	return values
+}
+
+// ValuesAtPath returns a list of values at the case insensitive lexical
+// path inside of a structure.
+func ValuesAtPath(i interface{}, path string) ([]interface{}, error) {
+	result, err := jmespath.Search(path, i)
+	if err != nil {
+		return nil, err
+	}
+
+	v := reflect.ValueOf(result)
+	if !v.IsValid() || (v.Kind() == reflect.Ptr && v.IsNil()) {
+		return nil, nil
+	}
+	if s, ok := result.([]interface{}); ok {
+		return s, err
+	}
+	if v.Kind() == reflect.Map && v.Len() == 0 {
+		return nil, nil
+	}
+	if v.Kind() == reflect.Slice {
+		out := make([]interface{}, v.Len())
+		for i := 0; i < v.Len(); i++ {
+			out[i] = v.Index(i).Interface()
+		}
+		return out, nil
+	}
+
+	return []interface{}{result}, nil
+}
+
+// SetValueAtPath sets a value at the case insensitive lexical path inside
+// of a structure.
+func SetValueAtPath(i interface{}, path string, v interface{}) {
+	if rvals := rValuesAtPath(i, path, true, false, v == nil); rvals != nil {
+		for _, rval := range rvals {
+			if rval.Kind() == reflect.Ptr && rval.IsNil() {
+				continue
+			}
+			setValue(rval, v)
+		}
+	}
+}
+
+func setValue(dstVal reflect.Value, src interface{}) {
+	if dstVal.Kind() == reflect.Ptr {
+		dstVal = reflect.Indirect(dstVal)
+	}
+	srcVal := reflect.ValueOf(src)
+
+	if !srcVal.IsValid() { // src is literal nil
+		if dstVal.CanAddr() {
+			// Convert to pointer so that pointer's value can be nil'ed
+			//                     dstVal = dstVal.Addr()
+		}
+		dstVal.Set(reflect.Zero(dstVal.Type()))
+
+	} else if srcVal.Kind() == reflect.Ptr {
+		if srcVal.IsNil() {
+			srcVal = reflect.Zero(dstVal.Type())
+		} else {
+			srcVal = reflect.ValueOf(src).Elem()
+		}
+		dstVal.Set(srcVal)
+	} else {
+		dstVal.Set(srcVal)
+	}
+
+}

vendor/github.com/aws/aws-sdk-go/aws/awsutil/prettify.go

+package awsutil
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"reflect"
+	"strings"
+)
+
+// Prettify returns the string representation of a value.
+func Prettify(i interface{}) string {
+	var buf bytes.Buffer
+	prettify(reflect.ValueOf(i), 0, &buf)
+	return buf.String()
+}
+
+// prettify will recursively walk value v to build a textual
+// representation of the value.
+func prettify(v reflect.Value, indent int, buf *bytes.Buffer) {
+	for v.Kind() == reflect.Ptr {
+		v = v.Elem()
+	}
+
+	switch v.Kind() {
+	case reflect.Struct:
+		strtype := v.Type().String()
+		if strtype == "time.Time" {
+			fmt.Fprintf(buf, "%s", v.Interface())
+			break
+		} else if strings.HasPrefix(strtype, "io.") {
+			buf.WriteString("<buffer>")
+			break
+		}
+
+		buf.WriteString("{\n")
+
+		names := []string{}
+		for i := 0; i < v.Type().NumField(); i++ {
+			name := v.Type().Field(i).Name
+			f := v.Field(i)
+			if name[0:1] == strings.ToLower(name[0:1]) {
+				continue // ignore unexported fields
+			}
+			if (f.Kind() == reflect.Ptr || f.Kind() == reflect.Slice || f.Kind() == reflect.Map) && f.IsNil() {
+				continue // ignore unset fields
+			}
+			names = append(names, name)
+		}
+
+		for i, n := range names {
+			val := v.FieldByName(n)
+			buf.WriteString(strings.Repeat(" ", indent+2))
+			buf.WriteString(n + ": ")
+			prettify(val, indent+2, buf)
+
+			if i < len(names)-1 {
+				buf.WriteString(",\n")
+			}
+		}
+
+		buf.WriteString("\n" + strings.Repeat(" ", indent) + "}")
+	case reflect.Slice:
+		strtype := v.Type().String()
+		if strtype == "[]uint8" {
+			fmt.Fprintf(buf, "<binary> len %d", v.Len())
+			break
+		}
+
+		nl, id, id2 := "", "", ""
+		if v.Len() > 3 {
+			nl, id, id2 = "\n", strings.Repeat(" ", indent), strings.Repeat(" ", indent+2)
+		}
+		buf.WriteString("[" + nl)
+		for i := 0; i < v.Len(); i++ {
+			buf.WriteString(id2)
+			prettify(v.Index(i), indent+2, buf)
+
+			if i < v.Len()-1 {
+				buf.WriteString("," + nl)
+			}
+		}
+
+		buf.WriteString(nl + id + "]")
+	case reflect.Map:
+		buf.WriteString("{\n")
+
+		for i, k := range v.MapKeys() {
+			buf.WriteString(strings.Repeat(" ", indent+2))
+			buf.WriteString(k.String() + ": ")
+			prettify(v.MapIndex(k), indent+2, buf)
+
+			if i < v.Len()-1 {
+				buf.WriteString(",\n")
+			}
+		}
+
+		buf.WriteString("\n" + strings.Repeat(" ", indent) + "}")
+	default:
+		if !v.IsValid() {
+			fmt.Fprint(buf, "<invalid value>")
+			return
+		}
+		format := "%v"
+		switch v.Interface().(type) {
+		case string:
+			format = "%q"
+		case io.ReadSeeker, io.Reader:
+			format = "buffer(%p)"
+		}
+		fmt.Fprintf(buf, format, v.Interface())
+	}
+}

vendor/github.com/aws/aws-sdk-go/aws/awsutil/string_value.go

+package awsutil
+
+import (
+	"bytes"
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+// StringValue returns the string representation of a value.
+func StringValue(i interface{}) string {
+	var buf bytes.Buffer
+	stringValue(reflect.ValueOf(i), 0, &buf)
+	return buf.String()
+}
+
+func stringValue(v reflect.Value, indent int, buf *bytes.Buffer) {
+	for v.Kind() == reflect.Ptr {
+		v = v.Elem()
+	}
+
+	switch v.Kind() {
+	case reflect.Struct:
+		buf.WriteString("{\n")
+
+		names := []string{}
+		for i := 0; i < v.Type().NumField(); i++ {
+			name := v.Type().Field(i).Name
+			f := v.Field(i)
+			if name[0:1] == strings.ToLower(name[0:1]) {
+				continue // ignore unexported fields
+			}
+			if (f.Kind() == reflect.Ptr || f.Kind() == reflect.Slice) && f.IsNil() {
+				continue // ignore unset fields
+			}
+			names = append(names, name)
+		}
+
+		for i, n := range names {
+			val := v.FieldByName(n)
+			buf.WriteString(strings.Repeat(" ", indent+2))
+			buf.WriteString(n + ": ")
+			stringValue(val, indent+2, buf)
+
+			if i < len(names)-1 {
+				buf.WriteString(",\n")
+			}
+		}
+
+		buf.WriteString("\n" + strings.Repeat(" ", indent) + "}")
+	case reflect.Slice:
+		nl, id, id2 := "", "", ""
+		if v.Len() > 3 {
+			nl, id, id2 = "\n", strings.Repeat(" ", indent), strings.Repeat(" ", indent+2)
+		}
+		buf.WriteString("[" + nl)
+		for i := 0; i < v.Len(); i++ {
+			buf.WriteString(id2)
+			stringValue(v.Index(i), indent+2, buf)
+
+			if i < v.Len()-1 {
+				buf.WriteString("," + nl)
+			}
+		}
+
+		buf.WriteString(nl + id + "]")
+	case reflect.Map:
+		buf.WriteString("{\n")
+
+		for i, k := range v.MapKeys() {
+			buf.WriteString(strings.Repeat(" ", indent+2))
+			buf.WriteString(k.String() + ": ")
+			stringValue(v.MapIndex(k), indent+2, buf)
+
+			if i < v.Len()-1 {
+				buf.WriteString(",\n")
+			}
+		}
+
+		buf.WriteString("\n" + strings.Repeat(" ", indent) + "}")
+	default:
+		format := "%v"
+		switch v.Interface().(type) {
+		case string:
+			format = "%q"
+		}
+		fmt.Fprintf(buf, format, v.Interface())
+	}
+}

vendor/github.com/aws/aws-sdk-go/aws/client/metadata/client_info.go

+package metadata
+
+// ClientInfo wraps immutable data from the client.Client structure.
+type ClientInfo struct {
+	ServiceName   string
+	APIVersion    string
+	Endpoint      string
+	SigningName   string
+	SigningRegion string
+	JSONVersion   string
+	TargetPrefix  string
+}

vendor/github.com/aws/aws-sdk-go/aws/config.go

+package aws
+
+import (
+	"net/http"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/aws/aws-sdk-go/aws/endpoints"
+)
+
+// UseServiceDefaultRetries instructs the config to use the service's own
+// default number of retries. This will be the default action if
+// Config.MaxRetries is nil also.
+const UseServiceDefaultRetries = -1
+
+// RequestRetryer is an alias for a type that implements the request.Retryer
+// interface.
+type RequestRetryer interface{}
+
+// A Config provides service configuration for service clients. By default,
+// all clients will use the defaults.DefaultConfig tructure.
+//
+//     // Create Session with MaxRetry configuration to be shared by multiple
+//     // service clients.
+//     sess := session.Must(session.NewSession(&aws.Config{
+//         MaxRetries: aws.Int(3),
+//     }))
+//
+//     // Create S3 service client with a specific Region.
+//     svc := s3.New(sess, &aws.Config{
+//         Region: aws.String("us-west-2"),
+//     })
+type Config struct {
+	// Enables verbose error printing of all credential chain errors.
+	// Should be used when wanting to see all errors while attempting to
+	// retrieve credentials.
+	CredentialsChainVerboseErrors *bool
+
+	// The credentials object to use when signing requests. Defaults to a
+	// chain of credential providers to search for credentials in environment
+	// variables, shared credential file, and EC2 Instance Roles.
+	Credentials *credentials.Credentials
+
+	// An optional endpoint URL (hostname only or fully qualified URI)
+	// that overrides the default generated endpoint for a client. Set this
+	// to `""` to use the default generated endpoint.
+	//
+	// @note You must still provide a `Region` value when specifying an
+	//   endpoint for a client.
+	Endpoint *string
+
+	// The resolver to use for looking up endpoints for AWS service clients
+	// to use based on region.
+	EndpointResolver endpoints.Resolver
+
+	// The region to send requests to. This parameter is required and must
+	// be configured globally or on a per-client basis unless otherwise
+	// noted. A full list of regions is found in the "Regions and Endpoints"
+	// document.
+	//
+	// @see http://docs.aws.amazon.com/general/latest/gr/rande.html
+	//   AWS Regions and Endpoints
+	Region *string
+
+	// Set this to `true` to disable SSL when sending requests. Defaults
+	// to `false`.
+	DisableSSL *bool
+
+	// The HTTP client to use when sending requests. Defaults to
+	// `http.DefaultClient`.
+	HTTPClient *http.Client
+
+	// An integer value representing the logging level. The default log level
+	// is zero (LogOff), which represents no logging. To enable logging set
+	// to a LogLevel Value.
+	LogLevel *LogLevelType
+
+	// The logger writer interface to write logging messages to. Defaults to
+	// standard out.
+	Logger Logger
+
+	// The maximum number of times that a request will be retried for failures.
+	// Defaults to -1, which defers the max retry setting to the service
+	// specific configuration.
+	MaxRetries *int
+
+	// Retryer guides how HTTP requests should be retried in case of
+	// recoverable failures.
+	//
+	// When nil or the value does not implement the request.Retryer interface,
+	// the request.DefaultRetryer will be used.
+	//
+	// When both Retryer and MaxRetries are non-nil, the former is used and
+	// the latter ignored.
+	//
+	// To set the Retryer field in a type-safe manner and with chaining, use
+	// the request.WithRetryer helper function:
+	//
+	//   cfg := request.WithRetryer(aws.NewConfig(), myRetryer)
+	//
+	Retryer RequestRetryer
+
+	// Disables semantic parameter validation, which validates input for
+	// missing required fields and/or other semantic request input errors.
+	DisableParamValidation *bool
+
+	// Disables the computation of request and response checksums, e.g.,
+	// CRC32 checksums in Amazon DynamoDB.
+	DisableComputeChecksums *bool
+
+	// Set this to `true` to force the request to use path-style addressing,
+	// i.e., `http://s3.amazonaws.com/BUCKET/KEY`. By default, the S3 client
+	// will use virtual hosted bucket addressing when possible
+	// (`http://BUCKET.s3.amazonaws.com/KEY`).
+	//
+	// @note This configuration option is specific to the Amazon S3 service.
+	// @see http://docs.aws.amazon.com/AmazonS3/latest/dev/VirtualHosting.html
+	//   Amazon S3: Virtual Hosting of Buckets
+	S3ForcePathStyle *bool
+
+	// Set this to `true` to disable the SDK adding the `Expect: 100-Continue`
+	// header to PUT requests over 2MB of content. 100-Continue instructs the
+	// HTTP client not to send the body until the service responds with a
+	// `continue` status. This is useful to prevent sending the request body
+	// until after the request is authenticated, and validated.
+	//
+	// http://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectPUT.html
+	//
+	// 100-Continue is only enabled for Go 1.6 and above. See `http.Transport`'s
+	// `ExpectContinueTimeout` for information on adjusting the continue wait
+	// timeout. https://golang.org/pkg/net/http/#Transport
+	//
+	// You should use this flag to disble 100-Continue if you experience issues
+	// with proxies or third party S3 compatible services.
+	S3Disable100Continue *bool
+
+	// Set this to `true` to enable S3 Accelerate feature. For all operations
+	// compatible with S3 Accelerate will use the accelerate endpoint for
+	// requests. Requests not compatible will fall back to normal S3 requests.
+	//
+	// The bucket must be enable for accelerate to be used with S3 client with
+	// accelerate enabled. If the bucket is not enabled for accelerate an error
+	// will be returned. The bucket name must be DNS compatible to also work
+	// with accelerate.
+	S3UseAccelerate *bool
+
+	// Set this to `true` to disable the EC2Metadata client from overriding the
+	// default http.Client's Timeout. This is helpful if you do not want the
+	// EC2Metadata client to create a new http.Client. This options is only
+	// meaningful if you're not already using a custom HTTP client with the
+	// SDK. Enabled by default.
+	//
+	// Must be set and provided to the session.NewSession() in order to disable
+	// the EC2Metadata overriding the timeout for default credentials chain.
+	//
+	// Example:
+	//    sess := session.Must(session.NewSession(aws.NewConfig()
+	//       .WithEC2MetadataDiableTimeoutOverride(true)))
+	//
+	//    svc := s3.New(sess)
+	//
+	EC2MetadataDisableTimeoutOverride *bool
+
+	// Instructs the endpiont to be generated for a service client to
+	// be the dual stack endpoint. The dual stack endpoint will support
+	// both IPv4 and IPv6 addressing.
+	//
+	// Setting this for a service which does not support dual stack will fail
+	// to make requets. It is not recommended to set this value on the session
+	// as it will apply to all service clients created with the session. Even
+	// services which don't support dual stack endpoints.
+	//
+	// If the Endpoint config value is also provided the UseDualStack flag
+	// will be ignored.
+	//
+	// Only supported with.
+	//
+	//     sess := session.Must(session.NewSession())
+	//
+	//     svc := s3.New(sess, &aws.Config{
+	//         UseDualStack: aws.Bool(true),
+	//     })
+	UseDualStack *bool
+
+	// SleepDelay is an override for the func the SDK will call when sleeping
+	// during the lifecycle of a request. Specifically this will be used for
+	// request delays. This value should only be used for testing. To adjust
+	// the delay of a request see the aws/client.DefaultRetryer and
+	// aws/request.Retryer.
+	SleepDelay func(time.Duration)
+
+	// DisableRestProtocolURICleaning will not clean the URL path when making rest protocol requests.
+	// Will default to false. This would only be used for empty directory names in s3 requests.
+	//
+	// Example:
+	//    sess := session.Must(session.NewSession(&aws.Config{
+	//         DisableRestProtocolURICleaning: aws.Bool(true),
+	//    }))
+	//
+	//    svc := s3.New(sess)
+	//    out, err := svc.GetObject(&s3.GetObjectInput {
+	//    	Bucket: aws.String("bucketname"),
+	//    	Key: aws.String("//foo//bar//moo"),
+	//    })
+	DisableRestProtocolURICleaning *bool
+}
+
+// NewConfig returns a new Config pointer that can be chained with builder
+// methods to set multiple configuration values inline without using pointers.
+//
+//     // Create Session with MaxRetry configuration to be shared by multiple
+//     // service clients.
+//     sess := session.Must(session.NewSession(aws.NewConfig().
+//         WithMaxRetries(3),
+//     ))
+//
+//     // Create S3 service client with a specific Region.
+//     svc := s3.New(sess, aws.NewConfig().
+//         WithRegion("us-west-2"),
+//     )
+func NewConfig() *Config {
+	return &Config{}
+}
+
+// WithCredentialsChainVerboseErrors sets a config verbose errors boolean and returning
+// a Config pointer.
+func (c *Config) WithCredentialsChainVerboseErrors(verboseErrs bool) *Config {
+	c.CredentialsChainVerboseErrors = &verboseErrs
+	return c
+}
+
+// WithCredentials sets a config Credentials value returning a Config pointer
+// for chaining.
+func (c *Config) WithCredentials(creds *credentials.Credentials) *Config {
+	c.Credentials = creds
+	return c
+}
+
+// WithEndpoint sets a config Endpoint value returning a Config pointer for
+// chaining.
+func (c *Config) WithEndpoint(endpoint string) *Config {
+	c.Endpoint = &endpoint
+	return c
+}
+
+// WithEndpointResolver sets a config EndpointResolver value returning a
+// Config pointer for chaining.
+func (c *Config) WithEndpointResolver(resolver endpoints.Resolver) *Config {
+	c.EndpointResolver = resolver
+	return c
+}
+
+// WithRegion sets a config Region value returning a Config pointer for
+// chaining.
+func (c *Config) WithRegion(region string) *Config {
+	c.Region = &region
+	return c
+}
+
+// WithDisableSSL sets a config DisableSSL value returning a Config pointer
+// for chaining.
+func (c *Config) WithDisableSSL(disable bool) *Config {
+	c.DisableSSL = &disable
+	return c
+}
+
+// WithHTTPClient sets a config HTTPClient value returning a Config pointer
+// for chaining.
+func (c *Config) WithHTTPClient(client *http.Client) *Config {
+	c.HTTPClient = client
+	return c
+}
+
+// WithMaxRetries sets a config MaxRetries value returning a Config pointer
+// for chaining.
+func (c *Config) WithMaxRetries(max int) *Config {
+	c.MaxRetries = &max
+	return c
+}
+
+// WithDisableParamValidation sets a config DisableParamValidation value
+// returning a Config pointer for chaining.
+func (c *Config) WithDisableParamValidation(disable bool) *Config {
+	c.DisableParamValidation = &disable
+	return c
+}
+
+// WithDisableComputeChecksums sets a config DisableComputeChecksums value
+// returning a Config pointer for chaining.
+func (c *Config) WithDisableComputeChecksums(disable bool) *Config {
+	c.DisableComputeChecksums = &disable
+	return c
+}
+
+// WithLogLevel sets a config LogLevel value returning a Config pointer for
+// chaining.
+func (c *Config) WithLogLevel(level LogLevelType) *Config {
+	c.LogLevel = &level
+	return c
+}
+
+// WithLogger sets a config Logger value returning a Config pointer for
+// chaining.
+func (c *Config) WithLogger(logger Logger) *Config {
+	c.Logger = logger
+	return c
+}
+
+// WithS3ForcePathStyle sets a config S3ForcePathStyle value returning a Config
+// pointer for chaining.
+func (c *Config) WithS3ForcePathStyle(force bool) *Config {
+	c.S3ForcePathStyle = &force
+	return c
+}
+
+// WithS3Disable100Continue sets a config S3Disable100Continue value returning
+// a Config pointer for chaining.
+func (c *Config) WithS3Disable100Continue(disable bool) *Config {
+	c.S3Disable100Continue = &disable
+	return c
+}
+
+// WithS3UseAccelerate sets a config S3UseAccelerate value returning a Config
+// pointer for chaining.
+func (c *Config) WithS3UseAccelerate(enable bool) *Config {
+	c.S3UseAccelerate = &enable
+	return c
+}
+
+// WithUseDualStack sets a config UseDualStack value returning a Config
+// pointer for chaining.
+func (c *Config) WithUseDualStack(enable bool) *Config {
+	c.UseDualStack = &enable
+	return c
+}
+
+// WithEC2MetadataDisableTimeoutOverride sets a config EC2MetadataDisableTimeoutOverride value
+// returning a Config pointer for chaining.
+func (c *Config) WithEC2MetadataDisableTimeoutOverride(enable bool) *Config {
+	c.EC2MetadataDisableTimeoutOverride = &enable
+	return c
+}
+
+// WithSleepDelay overrides the function used to sleep while waiting for the
+// next retry. Defaults to time.Sleep.
+func (c *Config) WithSleepDelay(fn func(time.Duration)) *Config {
+	c.SleepDelay = fn
+	return c
+}
+
+// MergeIn merges the passed in configs into the existing config object.
+func (c *Config) MergeIn(cfgs ...*Config) {
+	for _, other := range cfgs {
+		mergeInConfig(c, other)
+	}
+}
+
+func mergeInConfig(dst *Config, other *Config) {
+	if other == nil {
+		return
+	}
+
+	if other.CredentialsChainVerboseErrors != nil {
+		dst.CredentialsChainVerboseErrors = other.CredentialsChainVerboseErrors
+	}
+
+	if other.Credentials != nil {
+		dst.Credentials = other.Credentials
+	}
+
+	if other.Endpoint != nil {
+		dst.Endpoint = other.Endpoint
+	}
+
+	if other.EndpointResolver != nil {
+		dst.EndpointResolver = other.EndpointResolver
+	}
+
+	if other.Region != nil {
+		dst.Region = other.Region
+	}
+
+	if other.DisableSSL != nil {
+		dst.DisableSSL = other.DisableSSL
+	}
+
+	if other.HTTPClient != nil {
+		dst.HTTPClient = other.HTTPClient
+	}
+
+	if other.LogLevel != nil {
+		dst.LogLevel = other.LogLevel
+	}
+
+	if other.Logger != nil {
+		dst.Logger = other.Logger
+	}
+
+	if other.MaxRetries != nil {
+		dst.MaxRetries = other.MaxRetries
+	}
+
+	if other.Retryer != nil {
+		dst.Retryer = other.Retryer
+	}
+
+	if other.DisableParamValidation != nil {
+		dst.DisableParamValidation = other.DisableParamValidation
+	}
+
+	if other.DisableComputeChecksums != nil {
+		dst.DisableComputeChecksums = other.DisableComputeChecksums
+	}
+
+	if other.S3ForcePathStyle != nil {
+		dst.S3ForcePathStyle = other.S3ForcePathStyle
+	}
+
+	if other.S3Disable100Continue != nil {
+		dst.S3Disable100Continue = other.S3Disable100Continue
+	}
+
+	if other.S3UseAccelerate != nil {
+		dst.S3UseAccelerate = other.S3UseAccelerate
+	}
+
+	if other.UseDualStack != nil {
+		dst.UseDualStack = other.UseDualStack
+	}
+
+	if other.EC2MetadataDisableTimeoutOverride != nil {
+		dst.EC2MetadataDisableTimeoutOverride = other.EC2MetadataDisableTimeoutOverride
+	}
+
+	if other.SleepDelay != nil {
+		dst.SleepDelay = other.SleepDelay
+	}
+
+	if other.DisableRestProtocolURICleaning != nil {
+		dst.DisableRestProtocolURICleaning = other.DisableRestProtocolURICleaning
+	}
+}
+
+// Copy will return a shallow copy of the Config object. If any additional
+// configurations are provided they will be merged into the new config returned.
+func (c *Config) Copy(cfgs ...*Config) *Config {
+	dst := &Config{}
+	dst.MergeIn(c)
+
+	for _, cfg := range cfgs {
+		dst.MergeIn(cfg)
+	}
+
+	return dst
+}

vendor/github.com/aws/aws-sdk-go/aws/convert_types.go

+package aws
+
+import "time"
+
+// String returns a pointer to the string value passed in.
+func String(v string) *string {
+	return &v
+}
+
+// StringValue returns the value of the string pointer passed in or
+// "" if the pointer is nil.
+func StringValue(v *string) string {
+	if v != nil {
+		return *v
+	}
+	return ""
+}
+
+// StringSlice converts a slice of string values into a slice of
+// string pointers
+func StringSlice(src []string) []*string {
+	dst := make([]*string, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// StringValueSlice converts a slice of string pointers into a slice of
+// string values
+func StringValueSlice(src []*string) []string {
+	dst := make([]string, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// StringMap converts a string map of string values into a string
+// map of string pointers
+func StringMap(src map[string]string) map[string]*string {
+	dst := make(map[string]*string)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// StringValueMap converts a string map of string pointers into a string
+// map of string values
+func StringValueMap(src map[string]*string) map[string]string {
+	dst := make(map[string]string)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
+
+// Bool returns a pointer to the bool value passed in.
+func Bool(v bool) *bool {
+	return &v
+}
+
+// BoolValue returns the value of the bool pointer passed in or
+// false if the pointer is nil.
+func BoolValue(v *bool) bool {
+	if v != nil {
+		return *v
+	}
+	return false
+}
+
+// BoolSlice converts a slice of bool values into a slice of
+// bool pointers
+func BoolSlice(src []bool) []*bool {
+	dst := make([]*bool, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// BoolValueSlice converts a slice of bool pointers into a slice of
+// bool values
+func BoolValueSlice(src []*bool) []bool {
+	dst := make([]bool, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// BoolMap converts a string map of bool values into a string
+// map of bool pointers
+func BoolMap(src map[string]bool) map[string]*bool {
+	dst := make(map[string]*bool)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// BoolValueMap converts a string map of bool pointers into a string
+// map of bool values
+func BoolValueMap(src map[string]*bool) map[string]bool {
+	dst := make(map[string]bool)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
+
+// Int returns a pointer to the int value passed in.
+func Int(v int) *int {
+	return &v
+}
+
+// IntValue returns the value of the int pointer passed in or
+// 0 if the pointer is nil.
+func IntValue(v *int) int {
+	if v != nil {
+		return *v
+	}
+	return 0
+}
+
+// IntSlice converts a slice of int values into a slice of
+// int pointers
+func IntSlice(src []int) []*int {
+	dst := make([]*int, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// IntValueSlice converts a slice of int pointers into a slice of
+// int values
+func IntValueSlice(src []*int) []int {
+	dst := make([]int, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// IntMap converts a string map of int values into a string
+// map of int pointers
+func IntMap(src map[string]int) map[string]*int {
+	dst := make(map[string]*int)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// IntValueMap converts a string map of int pointers into a string
+// map of int values
+func IntValueMap(src map[string]*int) map[string]int {
+	dst := make(map[string]int)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
+
+// Int64 returns a pointer to the int64 value passed in.
+func Int64(v int64) *int64 {
+	return &v
+}
+
+// Int64Value returns the value of the int64 pointer passed in or
+// 0 if the pointer is nil.
+func Int64Value(v *int64) int64 {
+	if v != nil {
+		return *v
+	}
+	return 0
+}
+
+// Int64Slice converts a slice of int64 values into a slice of
+// int64 pointers
+func Int64Slice(src []int64) []*int64 {
+	dst := make([]*int64, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// Int64ValueSlice converts a slice of int64 pointers into a slice of
+// int64 values
+func Int64ValueSlice(src []*int64) []int64 {
+	dst := make([]int64, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// Int64Map converts a string map of int64 values into a string
+// map of int64 pointers
+func Int64Map(src map[string]int64) map[string]*int64 {
+	dst := make(map[string]*int64)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// Int64ValueMap converts a string map of int64 pointers into a string
+// map of int64 values
+func Int64ValueMap(src map[string]*int64) map[string]int64 {
+	dst := make(map[string]int64)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
+
+// Float64 returns a pointer to the float64 value passed in.
+func Float64(v float64) *float64 {
+	return &v
+}
+
+// Float64Value returns the value of the float64 pointer passed in or
+// 0 if the pointer is nil.
+func Float64Value(v *float64) float64 {
+	if v != nil {
+		return *v
+	}
+	return 0
+}
+
+// Float64Slice converts a slice of float64 values into a slice of
+// float64 pointers
+func Float64Slice(src []float64) []*float64 {
+	dst := make([]*float64, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// Float64ValueSlice converts a slice of float64 pointers into a slice of
+// float64 values
+func Float64ValueSlice(src []*float64) []float64 {
+	dst := make([]float64, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// Float64Map converts a string map of float64 values into a string
+// map of float64 pointers
+func Float64Map(src map[string]float64) map[string]*float64 {
+	dst := make(map[string]*float64)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// Float64ValueMap converts a string map of float64 pointers into a string
+// map of float64 values
+func Float64ValueMap(src map[string]*float64) map[string]float64 {
+	dst := make(map[string]float64)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
+
+// Time returns a pointer to the time.Time value passed in.
+func Time(v time.Time) *time.Time {
+	return &v
+}
+
+// TimeValue returns the value of the time.Time pointer passed in or
+// time.Time{} if the pointer is nil.
+func TimeValue(v *time.Time) time.Time {
+	if v != nil {
+		return *v
+	}
+	return time.Time{}
+}
+
+// TimeUnixMilli returns a Unix timestamp in milliseconds from "January 1, 1970 UTC".
+// The result is undefined if the Unix time cannot be represented by an int64.
+// Which includes calling TimeUnixMilli on a zero Time is undefined.
+//
+// This utility is useful for service API's such as CloudWatch Logs which require
+// their unix time values to be in milliseconds.
+//
+// See Go stdlib https://golang.org/pkg/time/#Time.UnixNano for more information.
+func TimeUnixMilli(t time.Time) int64 {
+	return t.UnixNano() / int64(time.Millisecond/time.Nanosecond)
+}
+
+// TimeSlice converts a slice of time.Time values into a slice of
+// time.Time pointers
+func TimeSlice(src []time.Time) []*time.Time {
+	dst := make([]*time.Time, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// TimeValueSlice converts a slice of time.Time pointers into a slice of
+// time.Time values
+func TimeValueSlice(src []*time.Time) []time.Time {
+	dst := make([]time.Time, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// TimeMap converts a string map of time.Time values into a string
+// map of time.Time pointers
+func TimeMap(src map[string]time.Time) map[string]*time.Time {
+	dst := make(map[string]*time.Time)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// TimeValueMap converts a string map of time.Time pointers into a string
+// map of time.Time values
+func TimeValueMap(src map[string]*time.Time) map[string]time.Time {
+	dst := make(map[string]time.Time)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}

vendor/github.com/aws/aws-sdk-go/aws/credentials/chain_provider.go

+package credentials
+
+import (
+	"github.com/aws/aws-sdk-go/aws/awserr"
+)
+
+var (
+	// ErrNoValidProvidersFoundInChain Is returned when there are no valid
+	// providers in the ChainProvider.
+	//
+	// This has been deprecated. For verbose error messaging set
+	// aws.Config.CredentialsChainVerboseErrors to true
+	//
+	// @readonly
+	ErrNoValidProvidersFoundInChain = awserr.New("NoCredentialProviders",
+		`no valid providers in chain. Deprecated. 
+	For verbose messaging see aws.Config.CredentialsChainVerboseErrors`,
+		nil)
+)
+
+// A ChainProvider will search for a provider which returns credentials
+// and cache that provider until Retrieve is called again.
+//
+// The ChainProvider provides a way of chaining multiple providers together
+// which will pick the first available using priority order of the Providers
+// in the list.
+//
+// If none of the Providers retrieve valid credentials Value, ChainProvider's
+// Retrieve() will return the error ErrNoValidProvidersFoundInChain.
+//
+// If a Provider is found which returns valid credentials Value ChainProvider
+// will cache that Provider for all calls to IsExpired(), until Retrieve is
+// called again.
+//
+// Example of ChainProvider to be used with an EnvProvider and EC2RoleProvider.
+// In this example EnvProvider will first check if any credentials are available
+// via the environment variables. If there are none ChainProvider will check
+// the next Provider in the list, EC2RoleProvider in this case. If EC2RoleProvider
+// does not return any credentials ChainProvider will return the error
+// ErrNoValidProvidersFoundInChain
+//
+//     creds := NewChainCredentials(
+//         []Provider{
+//             &EnvProvider{},
+//             &EC2RoleProvider{
+//                 Client: ec2metadata.New(sess),
+//             },
+//         })
+//
+//     // Usage of ChainCredentials with aws.Config
+//     svc := ec2.New(&aws.Config{Credentials: creds})
+//
+type ChainProvider struct {
+	Providers     []Provider
+	curr          Provider
+	VerboseErrors bool
+}
+
+// NewChainCredentials returns a pointer to a new Credentials object
+// wrapping a chain of providers.
+func NewChainCredentials(providers []Provider) *Credentials {
+	return NewCredentials(&ChainProvider{
+		Providers: append([]Provider{}, providers...),
+	})
+}
+
+// Retrieve returns the credentials value or error if no provider returned
+// without error.
+//
+// If a provider is found it will be cached and any calls to IsExpired()
+// will return the expired state of the cached provider.
+func (c *ChainProvider) Retrieve() (Value, error) {
+	var errs []error
+	for _, p := range c.Providers {
+		creds, err := p.Retrieve()
+		if err == nil {
+			c.curr = p
+			return creds, nil
+		}
+		errs = append(errs, err)
+	}
+	c.curr = nil
+
+	var err error
+	err = ErrNoValidProvidersFoundInChain
+	if c.VerboseErrors {
+		err = awserr.NewBatchError("NoCredentialProviders", "no valid providers in chain", errs)
+	}
+	return Value{}, err
+}
+
+// IsExpired will returned the expired state of the currently cached provider
+// if there is one.  If there is no current provider, true will be returned.
+func (c *ChainProvider) IsExpired() bool {
+	if c.curr != nil {
+		return c.curr.IsExpired()
+	}
+
+	return true
+}

vendor/github.com/aws/aws-sdk-go/aws/credentials/credentials.go

+// Package credentials provides credential retrieval and management
+//
+// The Credentials is the primary method of getting access to and managing
+// credentials Values. Using dependency injection retrieval of the credential
+// values is handled by a object which satisfies the Provider interface.
+//
+// By default the Credentials.Get() will cache the successful result of a
+// Provider's Retrieve() until Provider.IsExpired() returns true. At which
+// point Credentials will call Provider's Retrieve() to get new credential Value.
+//
+// The Provider is responsible for determining when credentials Value have expired.
+// It is also important to note that Credentials will always call Retrieve the
+// first time Credentials.Get() is called.
+//
+// Example of using the environment variable credentials.
+//
+//     creds := NewEnvCredentials()
+//
+//     // Retrieve the credentials value
+//     credValue, err := creds.Get()
+//     if err != nil {
+//         // handle error
+//     }
+//
+// Example of forcing credentials to expire and be refreshed on the next Get().
+// This may be helpful to proactively expire credentials and refresh them sooner
+// than they would naturally expire on their own.
+//
+//     creds := NewCredentials(&EC2RoleProvider{})
+//     creds.Expire()
+//     credsValue, err := creds.Get()
+//     // New credentials will be retrieved instead of from cache.
+//
+//
+// Custom Provider
+//
+// Each Provider built into this package also provides a helper method to generate
+// a Credentials pointer setup with the provider. To use a custom Provider just
+// create a type which satisfies the Provider interface and pass it to the
+// NewCredentials method.
+//
+//     type MyProvider struct{}
+//     func (m *MyProvider) Retrieve() (Value, error) {...}
+//     func (m *MyProvider) IsExpired() bool {...}
+//
+//     creds := NewCredentials(&MyProvider{})
+//     credValue, err := creds.Get()
+//
+package credentials
+
+import (
+	"sync"
+	"time"
+)
+
+// AnonymousCredentials is an empty Credential object that can be used as
+// dummy placeholder credentials for requests that do not need signed.
+//
+// This Credentials can be used to configure a service to not sign requests
+// when making service API calls. For example, when accessing public
+// s3 buckets.
+//
+//     svc := s3.New(&aws.Config{Credentials: AnonymousCredentials})
+//     // Access public S3 buckets.
+//
+// @readonly
+var AnonymousCredentials = NewStaticCredentials("", "", "")
+
+// A Value is the AWS credentials value for individual credential fields.
+type Value struct {
+	// AWS Access key ID
+	AccessKeyID string
+
+	// AWS Secret Access Key
+	SecretAccessKey string
+
+	// AWS Session Token
+	SessionToken string
+
+	// Provider used to get credentials
+	ProviderName string
+}
+
+// A Provider is the interface for any component which will provide credentials
+// Value. A provider is required to manage its own Expired state, and what to
+// be expired means.
+//
+// The Provider should not need to implement its own mutexes, because
+// that will be managed by Credentials.
+type Provider interface {
+	// Refresh returns nil if it successfully retrieved the value.
+	// Error is returned if the value were not obtainable, or empty.
+	Retrieve() (Value, error)
+
+	// IsExpired returns if the credentials are no longer valid, and need
+	// to be retrieved.
+	IsExpired() bool
+}
+
+// A Expiry provides shared expiration logic to be used by credentials
+// providers to implement expiry functionality.
+//
+// The best method to use this struct is as an anonymous field within the
+// provider's struct.
+//
+// Example:
+//     type EC2RoleProvider struct {
+//         Expiry
+//         ...
+//     }
+type Expiry struct {
+	// The date/time when to expire on
+	expiration time.Time
+
+	// If set will be used by IsExpired to determine the current time.
+	// Defaults to time.Now if CurrentTime is not set.  Available for testing
+	// to be able to mock out the current time.
+	CurrentTime func() time.Time
+}
+
+// SetExpiration sets the expiration IsExpired will check when called.
+//
+// If window is greater than 0 the expiration time will be reduced by the
+// window value.
+//
+// Using a window is helpful to trigger credentials to expire sooner than
+// the expiration time given to ensure no requests are made with expired
+// tokens.
+func (e *Expiry) SetExpiration(expiration time.Time, window time.Duration) {
+	e.expiration = expiration
+	if window > 0 {
+		e.expiration = e.expiration.Add(-window)
+	}
+}
+
+// IsExpired returns if the credentials are expired.
+func (e *Expiry) IsExpired() bool {
+	if e.CurrentTime == nil {
+		e.CurrentTime = time.Now
+	}
+	return e.expiration.Before(e.CurrentTime())
+}
+
+// A Credentials provides synchronous safe retrieval of AWS credentials Value.
+// Credentials will cache the credentials value until they expire. Once the value
+// expires the next Get will attempt to retrieve valid credentials.
+//
+// Credentials is safe to use across multiple goroutines and will manage the
+// synchronous state so the Providers do not need to implement their own
+// synchronization.
+//
+// The first Credentials.Get() will always call Provider.Retrieve() to get the
+// first instance of the credentials Value. All calls to Get() after that
+// will return the cached credentials Value until IsExpired() returns true.
+type Credentials struct {
+	creds        Value
+	forceRefresh bool
+	m            sync.Mutex
+
+	provider Provider
+}
+
+// NewCredentials returns a pointer to a new Credentials with the provider set.
+func NewCredentials(provider Provider) *Credentials {
+	return &Credentials{
+		provider:     provider,
+		forceRefresh: true,
+	}
+}
+
+// Get returns the credentials value, or error if the credentials Value failed
+// to be retrieved.
+//
+// Will return the cached credentials Value if it has not expired. If the
+// credentials Value has expired the Provider's Retrieve() will be called
+// to refresh the credentials.
+//
+// If Credentials.Expire() was called the credentials Value will be force
+// expired, and the next call to Get() will cause them to be refreshed.
+func (c *Credentials) Get() (Value, error) {
+	c.m.Lock()
+	defer c.m.Unlock()
+
+	if c.isExpired() {
+		creds, err := c.provider.Retrieve()
+		if err != nil {
+			return Value{}, err
+		}
+		c.creds = creds
+		c.forceRefresh = false
+	}
+
+	return c.creds, nil
+}
+
+// Expire expires the credentials and forces them to be retrieved on the
+// next call to Get().
+//
+// This will override the Provider's expired state, and force Credentials
+// to call the Provider's Retrieve().
+func (c *Credentials) Expire() {
+	c.m.Lock()
+	defer c.m.Unlock()
+
+	c.forceRefresh = true
+}
+
+// IsExpired returns if the credentials are no longer valid, and need
+// to be retrieved.
+//
+// If the Credentials were forced to be expired with Expire() this will
+// reflect that override.
+func (c *Credentials) IsExpired() bool {
+	c.m.Lock()
+	defer c.m.Unlock()
+
+	return c.isExpired()
+}
+
+// isExpired helper method wrapping the definition of expired credentials.
+func (c *Credentials) isExpired() bool {
+	return c.forceRefresh || c.provider.IsExpired()
+}