Add correct external_url to sentry response

The permalink for each issue in sentry response does not contain
protocol (http/https) and port. So, we construct a url from the api url
and the issue ID.

lib/sentry/client.rb

@@ -69,7 +69,12 @@ module Sentry
       end
     end
 
+    def issue_url(id)
+      "#{issues_api_url}#{id}/"
+    end
+
     def map_to_error(issue)
+      id = issue.fetch('id')
       project = issue.fetch('project')
 
       count = issue.fetch('count', nil)
@@ -77,8 +82,10 @@ module Sentry
       frequency = issue.dig('stats', '24h')
       message = issue.dig('metadata', 'value')
 
+      external_url = issue_url(id)
+
       Gitlab::ErrorTracking::Error.new(
-        id: issue.fetch('id'),
+        id: id,
         first_seen: issue.fetch('firstSeen', nil),
         last_seen: issue.fetch('lastSeen', nil),
         title: issue.fetch('title', nil),
@@ -87,7 +94,7 @@ module Sentry
         count: count,
         message: message,
         culprit: issue.fetch('culprit', nil),
-        external_url: issue.fetch('permalink', nil),
+        external_url: external_url,
         short_id: issue.fetch('shortId', nil),
         status: issue.fetch('status', nil),
         frequency: frequency,

spec/lib/sentry/client_spec.rb

@@ -41,7 +41,6 @@ describe Sentry::Client do
         :count        | :count
         :message      | [:metadata, :value]
         :culprit      | :culprit
-        :external_url | :permalink
         :short_id     | :shortId
         :status       | :status
         :frequency    | [:stats, '24h']
@@ -53,6 +52,12 @@ describe Sentry::Client do
       with_them do
         it { expect(subject[0].public_send(error_object)).to eq(sample_response[0].dig(*sentry_response)) }
       end
+
+      context 'external_url' do
+        it 'is constructed correctly' do
+          expect(subject[0].external_url).to eq('https://sentrytest.gitlab.com/api/0/projects/sentry-org/sentry-project/issues/11/')
+        end
+      end
     end
 
     context 'redirects' do