Return empty array if stack trace not present

- Add specs for issue_latest_event
- Remove previous changes to decorator

changelogs/unreleased/119205-500-when-error-stack-trace-is-empty.yml

+---
+title: Fix for 500 when error stack trace is empty
+merge_request: 119205
+author:
+type: fixed

lib/sentry/client.rb

@@ -187,13 +187,13 @@ module Sentry
 
     def parse_stack_trace(event)
       exception_entry = event.dig('entries')&.detect { |h| h['type'] == 'exception' }
-      return unless exception_entry
+      return [] unless exception_entry
 
       exception_values = exception_entry.dig('data', 'values')
       stack_trace_entry = exception_values&.detect { |h| h['stacktrace'].present? }
-      return unless stack_trace_entry
+      return [] unless stack_trace_entry
 
-      stack_trace_entry.dig('stacktrace', 'frames')
+      stack_trace_entry.dig('stacktrace', 'frames') || []
     end
 
     def map_to_error(issue)

spec/fixtures/sentry/issue_latest_event_no_stack_sample_response.json

+{
+  "eventID": "333b98e3b91341d8a6247edff171d8cf",
+  "dist": null,
+  "userReport": null,
+  "projectID": "1788822",
+  "previousEventID": "d32f1ce60de14911beec5109d9b5bdbd",
+  "message": null,
+  "id": "333b98e3b91341d8a6247edff171d8cf",
+  "size": 77202,
+  "errors": [
+    {
+      "data": {
+        "reason": "the cookie is missing a name/value pair",
+        "name": "request.cookies",
+        "value": "********"
+      },
+      "message": "Discarded invalid value",
+      "type": "invalid_data"
+    },
+    {
+      "data": {
+        "reason": "the cookie is missing a name/value pair",
+        "name": "request.cookies",
+        "value": "********"
+      },
+      "message": "Discarded invalid value",
+      "type": "invalid_data"
+    }
+  ],
+  "culprit": "/",
+  "title": "ActiveRecord::NoDatabaseError: FATAL:  database \"test_development\" does not exist",
+  "sdkUpdates": [],
+  "platform": "ruby",
+  "location": "active_record/connection_adapters/postgresql_adapter.rb",
+  "nextEventID": null,
+  "type": "error",
+  "metadata": {
+    "function": "rescue in connect",
+    "type": "ActiveRecord::NoDatabaseError",
+    "value": "FATAL:  database \"test_development\" does not exist\n",
+    "filename": "active_record/connection_adapters/postgresql_adapter.rb"
+  },
+  "groupingConfig": {
+    "enhancements": "eJybzDhxY3J-bm5-npWRgaGlroGxrpHxBABcTQcY",
+    "id": "newstyle:2019-05-08"
+  },
+  "crashFile": null,
+  "tags": [
+    {
+      "value": "Chrome 78.0.3904",
+      "key": "browser",
+      "_meta": null
+    },
+    {
+      "value": "Chrome",
+      "key": "browser.name",
+      "_meta": null
+    },
+    {
+      "value": "Mac OS X 10.15.1",
+      "key": "client_os",
+      "_meta": null
+    },
+    {
+      "value": "Mac OS X",
+      "key": "client_os.name",
+      "_meta": null
+    },
+    {
+      "value": "development",
+      "key": "environment",
+      "_meta": null
+    },
+    {
+      "value": "error",
+      "key": "level",
+      "_meta": null
+    },
+    {
+      "value": "ruby",
+      "key": "logger",
+      "_meta": null
+    },
+    {
+      "value": "b56ae26",
+      "key": "release",
+      "_meta": null
+    },
+    {
+      "value": "Seans-MBP.fritz.box",
+      "key": "server_name",
+      "_meta": null
+    },
+    {
+      "value": "/",
+      "key": "transaction",
+      "_meta": null
+    },
+    {
+      "value": "http://localhost:3001/",
+      "key": "url",
+      "_meta": null
+    },
+    {
+      "query": "user.ip:\"::1\"",
+      "value": "ip:::1",
+      "key": "user",
+      "_meta": null
+    }
+  ],
+  "dateCreated": "2019-12-08T21:48:07Z",
+  "dateReceived": "2019-12-08T21:48:08.579417Z",
+  "user": {
+    "username": null,
+    "name": null,
+    "ip_address": "::1",
+    "email": null,
+    "data": null,
+    "id": null
+  },
+  "entries": [],
+  "packages": {
+    "coffee-script": "2.4.1",
+    "uglifier": "4.1.20",
+    "ffi": "1.11.1",
+    "actioncable": "5.2.3",
+    "io-like": "0.3.0",
+    "rb-inotify": "0.10.0",
+    "spring": "2.1.0",
+    "loofah": "2.2.3",
+    "selenium-webdriver": "3.142.3",
+    "marcel": "0.3.3",
+    "sass-listen": "4.0.0",
+    "nokogiri": "1.10.4",
+    "activestorage": "5.2.3",
+    "activejob": "5.2.3",
+    "mimemagic": "0.3.3",
+    "faraday": "0.17.1",
+    "execjs": "2.7.0",
+    "activesupport": "5.2.3",
+    "rails-html-sanitizer": "1.2.0",
+    "byebug": "11.0.1",
+    "xpath": "3.2.0",
+    "msgpack": "1.3.1",
+    "childprocess": "1.0.1",
+    "rails-dom-testing": "2.0.3",
+    "public_suffix": "3.1.1",
+    "mini_mime": "1.0.2",
+    "arel": "9.0.0",
+    "coffee-rails": "4.2.2",
+    "bundler": "1.17.3",
+    "rails": "5.2.3",
+    "globalid": "0.4.2",
+    "sentry-raven": "2.12.3",
+    "concurrent-ruby": "1.1.5",
+    "capybara": "3.28.0",
+    "regexp_parser": "1.6.0",
+    "sprockets-rails": "3.2.1",
+    "tzinfo": "1.2.5",
+    "mail": "2.7.1",
+    "actionview": "5.2.3",
+    "rubyzip": "1.2.3",
+    "coffee-script-source": "1.12.2",
+    "listen": "3.1.5",
+    "i18n": "1.6.0",
+    "erubi": "1.8.0",
+    "rake": "12.3.3",
+    "nio4r": "2.4.0",
+    "activemodel": "5.2.3",
+    "web-console": "3.7.0",
+    "ruby_dep": "1.5.0",
+    "turbolinks": "5.2.0",
+    "archive-zip": "0.12.0",
+    "method_source": "0.9.2",
+    "minitest": "5.11.3",
+    "puma": "3.12.1",
+    "sass-rails": "5.1.0",
+    "chromedriver-helper": "2.1.1",
+    "sprockets": "3.7.2",
+    "bindex": "0.8.1",
+    "actionmailer": "5.2.3",
+    "rack-test": "1.1.0",
+    "bootsnap": "1.4.4",
+    "railties": "5.2.3",
+    "mini_portile2": "2.4.0",
+    "crass": "1.0.4",
+    "websocket-extensions": "0.1.4",
+    "multipart-post": "2.1.1",
+    "rb-fsevent": "0.10.3",
+    "jbuilder": "2.9.1",
+    "pg": "1.1.4",
+    "sass": "3.7.4",
+    "activerecord": "5.2.3",
+    "builder": "3.2.3",
+    "spring-watcher-listen": "2.0.1",
+    "websocket-driver": "0.7.1",
+    "thor": "0.20.3",
+    "thread_safe": "0.3.6",
+    "addressable": "2.6.0",
+    "prometheus-client-mmap": "0.9.8",
+    "tilt": "2.0.9",
+    "actionpack": "5.2.3",
+    "rack": "2.0.7",
+    "turbolinks-source": "5.2.0"
+  },
+  "sdk": {
+    "version": "2.12.3",
+    "name": "raven-ruby"
+  },
+  "_meta": {
+    "user": null,
+    "context": null,
+    "entries": {
+      "1": {
+        "data": {
+          "": null,
+          "cookies": {
+            "": {
+              "err": [
+                [
+                  "invalid_data",
+                  {
+                    "reason": "the cookie is missing a name/value pair"
+                  }
+                ]
+              ],
+              "val": "********"
+            }
+          },
+          "url": null,
+          "headers": null,
+          "env": null,
+          "query": null,
+          "data": null,
+          "method": null
+        }
+      }
+    },
+    "contexts": null,
+    "message": null,
+    "packages": null,
+    "tags": {},
+    "sdk": null
+  },
+  "contexts": {
+    "browser": {
+      "version": "78.0.3904",
+      "type": "browser",
+      "name": "Chrome"
+    },
+    "client_os": {
+      "version": "10.15.1",
+      "type": "os",
+      "name": "Mac OS X"
+    }
+  },
+  "fingerprints": [
+    "6aa133ea51857634f2d113de52b5cc61",
+    "e1613eeb169241eab95b76ab52a80c68"
+  ],
+  "context": {
+    "server": {
+      "runtime": {
+        "version": "ruby 2.6.3p62 (2019-04-16 revision 67580) [x86_64-darwin18]",
+        "name": "ruby"
+      },
+      "os": {
+        "kernel_version": "Darwin Seans-MBP.fritz.box 19.0.0 Darwin Kernel Version 19.0.0: Thu Oct 17 16:17:15 PDT 2019; root:xnu-6153.41.3~29/RELEASE_X86_64 x86_64",
+        "version": "Darwin Kernel Version 19.0.0: Thu Oct 17 16:17:15 PDT 2019; root:xnu-6153.41.3~29/RELEASE_X86_64",
+        "build": "19.0.0",
+        "name": "Darwin"
+      }
+    }
+  },
+  "release": {
+    "dateReleased": null,
+    "commitCount": 0,
+    "url": null,
+    "data": {},
+    "lastDeploy": null,
+    "deployCount": 0,
+    "dateCreated": "2019-12-08T21:47:47Z",
+    "lastEvent": "2019-12-09T21:52:05Z",
+    "version": "b56ae26",
+    "firstEvent": "2019-12-08T21:47:47Z",
+    "lastCommit": null,
+    "shortVersion": "b56ae26",
+    "authors": [],
+    "owner": null,
+    "newGroups": 26,
+    "ref": null,
+    "projects": [
+      {
+        "slug": "gitlab-03",
+        "name": "gitlab-03"
+      }
+    ]
+  },
+  "groupID": "1378364652"
+}
\ No newline at end of file

spec/lib/sentry/client_spec.rb

@@ -218,4 +218,62 @@ describe Sentry::Client do
       it_behaves_like 'issues has correct length', 1
     end
   end
+
+  describe '#issue_latest_event' do
+    let(:sample_response) do
+      Gitlab::Utils.deep_indifferent_access(
+        JSON.parse(fixture_file('sentry/issue_latest_event_sample_response.json'))
+      )
+    end
+
+    let(:issue_id) { '1234' }
+    let(:sentry_api_response) { sample_response }
+    let(:sentry_url) { 'https://sentrytest.gitlab.com/api/0' }
+    let(:sentry_request_url) { sentry_url + "/issues/#{issue_id}/events/latest/" }
+
+    let!(:sentry_api_request) { stub_sentry_request(sentry_request_url, body: sentry_api_response) }
+
+    subject { client.issue_latest_event(issue_id: issue_id) }
+
+    it_behaves_like 'calls sentry api'
+
+    it 'has correct return type' do
+      expect(subject).to be_a(Gitlab::ErrorTracking::ErrorEvent)
+    end
+
+    shared_examples 'assigns error tracking event correctly' do
+      using RSpec::Parameterized::TableSyntax
+
+      where(:event_object, :sentry_response) do
+        :issue_id           | :groupID
+        :date_received      | :dateReceived
+      end
+
+      with_them do
+        it { expect(subject.public_send(event_object)).to eq(sentry_api_response.dig(*sentry_response)) }
+      end
+    end
+
+    context 'error object created from sentry response' do
+      it_behaves_like 'assigns error tracking event correctly'
+
+      it 'parses the stack trace' do
+        expect(subject.stack_trace_entries).to be_a Array
+        expect(subject.stack_trace_entries).not_to be_empty
+      end
+
+      context 'error without stack trace' do
+        before do
+          sample_response['entries'] = []
+          stub_sentry_request(sentry_request_url, body: sample_response)
+        end
+
+        it_behaves_like 'assigns error tracking event correctly'
+
+        it 'returns an empty array for stack_trace_entries' do
+          expect(subject.stack_trace_entries).to eq []
+        end
+      end
+    end
+  end
 end