Group Faraday errors in Sentry by host

app/controllers/api/google_auth_controller.rb

@@ -23,7 +23,7 @@ def exchange_code
     private
 
     def faraday
-      Faraday.new do |f|
+      HttpClient.new do |f|
         f.request :url_encoded
         f.options.timeout = 10
         f.options.open_timeout = 5

app/services/subscriptions/pardot_form_handler_submitter.rb

@@ -39,7 +39,7 @@ def call(form_payload:)
     attr_reader :endpoint_url
 
     def faraday
-      @faraday ||= Faraday.new do |f|
+      @faraday ||= HttpClient.new do |f|
         f.request :url_encoded
         f.options.timeout = REQUEST_TIMEOUT_SECONDS
         f.options.open_timeout = OPEN_TIMEOUT_SECONDS

app/services/subscriptions/turnstile_verifier.rb

@@ -40,7 +40,7 @@ def passed?
     attr_reader :secret_key, :remote_ip, :token
 
     def faraday
-      @faraday ||= Faraday.new do |f|
+      @faraday ||= HttpClient.new do |f|
         f.request :url_encoded
         f.options.timeout = 5
         f.options.open_timeout = 2

config/initializers/sentry.rb

@@ -7,4 +7,12 @@
 
   config.rails.structured_logging.enabled = false
   config.traces_sample_rate = 0.1
+
+  config.before_send = lambda do |event, hint|
+    exception = hint[:exception]
+    next event unless exception.is_a?(Faraday::Error)
+
+    event.fingerprint = [exception.class.name, exception.try(:request_host) || 'unknown-host']
+    event
+  end
 end

lib/http_client.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require 'faraday'
+
+module HttpClient
+  def self.new(url = nil, options = {})
+    Faraday.new(url, options) do |f|
+      f.use RecordRequestHostInErrors
+      yield f
+    end
+  end
+end

lib/hydra_public_api_client.rb

@@ -50,7 +50,7 @@ def stubbed_user
   end
 
   def conn
-    @conn ||= Faraday.new(API_URL) do |f|
+    @conn ||= HttpClient.new(API_URL) do |f|
       f.request :url_encoded
       f.response :raise_error
       f.response :json

lib/profile_api_client.rb

@@ -221,7 +221,7 @@ def update_school_email_domains(token:, school_id:, school_email_domains: [])
     private
 
     def connection(token)
-      Faraday.new(ENV.fetch('IDENTITY_URL')) do |faraday|
+      HttpClient.new(ENV.fetch('IDENTITY_URL')) do |faraday|
         faraday.request :json
         faraday.response :json
         faraday.response :raise_error, allowed_statuses: [401]

lib/record_request_host_in_errors.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require 'faraday'
+
+class RecordRequestHostInErrors < Faraday::Middleware
+  module RequestHost
+    attr_accessor :request_host
+  end
+
+  def call(env)
+    super
+  rescue Faraday::Error => e
+    e.extend(RequestHost)
+    e.request_host = env.url.host
+    raise
+  end
+end

lib/scratch_asset_importer.rb

@@ -102,7 +102,7 @@ def s3_client
   end
 
   def connection
-    @connection ||= Faraday.new(url: asset_base_url) do |faraday|
+    @connection ||= HttpClient.new(url: asset_base_url) do |faraday|
       faraday.response :raise_error
     end
   end

lib/scratch_config_importer.rb

@@ -20,7 +20,7 @@ def import
   end
 
   def connection
-    Faraday.new(url: asset_config_url) do |faraday|
+    HttpClient.new(url: asset_config_url) do |faraday|
       faraday.response :raise_error
     end
   end

lib/tasks/integration_tests.rake

@@ -20,7 +20,7 @@ namespace :integration_tests do
   end
 
   def connection
-    Faraday.new do |faraday|
+    HttpClient.new do |faraday|
       faraday.request :json
       faraday.headers = {
         'Accept' => 'application/vnd.github+json',

lib/user_info_api_client.rb

@@ -49,7 +49,7 @@ def transform_result(result)
     end
 
     def conn
-      Faraday.new(
+      HttpClient.new(
         headers: { authorization: "Bearer #{API_KEY}" },
         url: API_URL
       ) do |f|

spec/configuration/sentry_config_spec.rb

@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe Sentry do
+  describe 'before_send' do
+    let(:event) { Sentry::ErrorEvent.new(configuration: described_class.configuration, integration_meta: nil) }
+
+    def fingerprint_for(exception)
+      described_class.configuration.before_send.call(event, { exception: }).fingerprint
+    end
+
+    it 'groups Faraday errors by class and request host' do
+      exception = Faraday::ServerError.new('boom')
+      exception.extend(RecordRequestHostInErrors::RequestHost)
+      exception.request_host = 'api.example.com'
+
+      expect(fingerprint_for(exception)).to eq(['Faraday::ServerError', 'api.example.com'])
+    end
+
+    it 'groups Faraday errors raised outside a request under an unknown host' do
+      expect(fingerprint_for(Faraday::TimeoutError.new)).to eq(['Faraday::TimeoutError', 'unknown-host'])
+    end
+
+    it 'leaves other exceptions on the default grouping' do
+      expect(fingerprint_for(StandardError.new)).to be_blank
+    end
+  end
+end

spec/lib/record_request_host_in_errors_spec.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe RecordRequestHostInErrors do
+  let(:connection) do
+    HttpClient.new('https://api.example.com') do |f|
+      f.response :raise_error
+    end
+  end
+
+  def request_host_from_error
+    connection.get('/things')
+    nil
+  rescue Faraday::Error => e
+    e.request_host
+  end
+
+  describe '#call' do
+    it 'records the host on errors raised by response middleware' do
+      stub_request(:get, 'https://api.example.com/things').to_return(status: 500)
+
+      expect(request_host_from_error).to eq('api.example.com')
+    end
+
+    it 'records the host on errors raised by the adapter' do
+      stub_request(:get, 'https://api.example.com/things').to_timeout
+
+      expect(request_host_from_error).to eq('api.example.com')
+    end
+  end
+end