chore(bundle): setup elastic_apm, disabled by default

Gemfile

@@ -27,6 +27,7 @@ gem 'devise-i18n'
 gem 'devise-two-factor'
 gem 'discard'
 gem 'dotenv-rails', require: 'dotenv/rails-now' # dotenv should always be loaded before rails
+gem 'elastic-apm'
 gem 'flipper'
 gem 'flipper-active_record'
 gem 'flipper-ui'

Gemfile.lock

@@ -220,6 +220,10 @@ GEM
     dumb_delegator (1.0.0)
     ecma-re-validator (0.3.0)
       regexp_parser (~> 2.0)
+    elastic-apm (4.6.0)
+      concurrent-ruby (~> 1.0)
+      http (>= 3.0)
+      ruby2_keywords
     encryptor (3.0.0)
     erubi (1.12.0)
     et-orbi (1.2.4)
@@ -249,6 +253,9 @@ GEM
     faraday-patron (1.0.0)
     faraday-rack (1.0.0)
     ffi (1.15.5)
+    ffi-compiler (1.0.1)
+      ffi (>= 1.0.0)
+      rake
     flipper (0.26.0)
       concurrent-ruby (< 2)
     flipper-active_record (0.26.0)
@@ -323,9 +330,15 @@ GEM
     highline (2.0.3)
     html_tokenizer (0.0.7)
     htmlentities (4.3.4)
+    http (5.1.1)
+      addressable (~> 2.8)
+      http-cookie (~> 1.0)
+      http-form_data (~> 2.2)
+      llhttp-ffi (~> 0.4.0)
     http-accept (1.7.0)
     http-cookie (1.0.3)
       domain_name (~> 0.5)
+    http-form_data (2.3.0)
     http_accept_language (2.1.1)
     httpclient (2.8.3)
     i18n (1.12.0)
@@ -390,6 +403,9 @@ GEM
     listen (3.4.1)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
+    llhttp-ffi (0.4.0)
+      ffi-compiler (~> 1.0)
+      rake (~> 13.0)
     lograge (0.11.2)
       actionpack (>= 4)
       activesupport (>= 4)
@@ -838,6 +854,7 @@ DEPENDENCIES
   devise-two-factor
   discard
   dotenv-rails
+  elastic-apm
   factory_bot
   flipper
   flipper-active_record

config/elastic_apm.yml

@@ -0,0 +1,8 @@
+# Set options ELASTIC_APM_SERVER_URL & ELASTIC_APM_SECRET_TOKEN by env vars instead
+# See https://www.elastic.co/guide/en/apm/agent/ruby/current/configuration.html
+#
+# server_url: ''
+# secret_token: ''
+
+# Enable it with ELASTIC_APM_ENABLED="true"
+enabled: false