Initial implementation of an elasticsearch indexer in Go

Closes #1 (closed)

elastic/client.go

@@ -2,6 +2,8 @@ package elastic
 import (
 	"context"
+	"fmt"
+	"os"
 	"strings"
 	"github.com/aws/aws-sdk-go/aws/credentials"
@@ -14,8 +16,9 @@ var (
 	// TODO: make this configurable / detectable.
 	// Limiting to 10MiB lets us work on small AWS clusters, but unnecessarily
 	// increases round trips in larger or non-AWS clusters
-	MaxBulkSize = 10 * 1024 * 1024
-	BulkWorkers = 2
+	MaxBulkSize  = 10 * 1024 * 1024
+	BulkWorkers  = 2
+	timeoutError = fmt.Errorf("Timeout")
 )
 type Client struct {
@@ -23,8 +26,17 @@ type Client struct {
 	bulk   *elastic.BulkProcessor
 }
-func (c *Client) Flush() error {
-	return c.bulk.Flush()
+// FromEnv creates an Elasticsearch client from the `ELASTIC_CONNECTION_INFO`
+// environment variable
+func FromEnv() (*Client, error) {
+	data := strings.NewReader(os.Getenv("ELASTIC_CONNECTION_INFO"))
+
+	config, err := ReadConfig(data)
+	if err != nil {
+		return nil, fmt.Errorf("Couldn't parse ELASTIC_CONNECTION_INFO: %s", err)
+	}
+
+	return NewClient(config)
 }
 func NewClient(config *Config) (*Client, error) {
@@ -68,3 +80,33 @@ func NewClient(config *Config) (*Client, error) {
 	return &Client{client: client, bulk: bulk}, nil
 }
+
+func (c *Client) Flush() error {
+	return c.bulk.Flush()
+}
+
+func (c *Client) CreateIndex(indexName, mapping string) error {
+	createIndex, err := c.client.CreateIndex(indexName).BodyString(mapping).Do(context.Background())
+	if err != nil {
+		return err
+	}
+
+	if !createIndex.Acknowledged {
+		return timeoutError
+	}
+
+	return nil
+}
+
+func (c *Client) DeleteIndex(indexName string) error {
+	deleteIndex, err := c.client.DeleteIndex(indexName).Do(context.Background())
+	if err != nil {
+		return err
+	}
+
+	if !deleteIndex.Acknowledged {
+		return timeoutError
+	}
+
+	return nil
+}