Show log corresponding to env in admin/logs

No matter which environment Gitlab was running as, the admin/logs view
always showed production.log. This commit selects the logfile based
on Rails.env.

- Rename ProductionLogger to EnvironmentLogger
- Make EnvironmentLogger logfile depend on env
- Update spinach test for log tabs

CHANGELOG.md

@@ -4,6 +4,7 @@ entry.
 ## 8.14.0 (2016-11-22)
+- Show correct environment log in admin/logs (@duk3luk3 !7191)
 - Fix Milestone dropdown not stay selected for `Upcoming` and `No Milestone` option !7117
 - Backups do not fail anymore when using tar on annex and custom_hooks only. !5814
 - Adds user project membership expired event to clarify why user was removed (Callum Dryden)

app/views/admin/logs/show.html.haml

 - @no_container = true
 - page_title "Logs"
 - loggers = [Gitlab::GitLogger, Gitlab::AppLogger,
-             Gitlab::ProductionLogger, Gitlab::SidekiqLogger,
+             Gitlab::EnvironmentLogger, Gitlab::SidekiqLogger,
              Gitlab::RepositoryCheckLogger]
 = render 'admin/background_jobs/head'

doc/administration/logs.md

@@ -13,7 +13,8 @@ This guide talks about how to read and use these system log files.
 This file lives in `/var/log/gitlab/gitlab-rails/production.log` for
 omnibus package or in `/home/git/gitlab/log/production.log` for
-installations from source.
+installations from source. (When Gitlab is running in an environment
+other than production, the corresponding logfile is shown here.)
 It contains information about all performed requests. You can see the
 URL and type of request, IP address and what exactly parts of code were

features/steps/admin/logs.rb

@@ -4,7 +4,7 @@ class Spinach::Features::AdminLogs < Spinach::FeatureSteps
   include SharedAdmin
   step 'I should see tabs with available logs' do
-    expect(page).to have_content 'production.log'
+    expect(page).to have_content 'test.log'
     expect(page).to have_content 'githost.log'
     expect(page).to have_content 'application.log'
   end

lib/gitlab/production_logger.rb → lib/gitlab/environment_logger.rb

 module Gitlab
-  class ProductionLogger < Gitlab::Logger
+  class EnvironmentLogger < Gitlab::Logger
     def self.file_name_noext
-      'production'
+      Rails.env
     end
   end
 end