Fix image webhook rewriting for uploads

This rewrote URLs to be absolute URLs. However, for uploads (the most
common case), we actually need them to point to not just the GitLab
instance, but the project they're from. Thankfully, we can normally get
that information from the object we're building the hook for.

6 files changed, 113 insertions, 53 deletions

diff --git a/changelogs/unreleased/test-usage-ping-in-timeout-case.yml b/changelogs/unreleased/test-usage-ping-in-timeout-case.yml
new file mode 100644
index 00000000000..daee98765ac
--- /dev/null
+++ b/changelogs/unreleased/test-usage-ping-in-timeout-case.yml
@@ -0,0 +1,5 @@
+---
+title: Fix auto-corrected upload URLs in webhooks
+merge_request: 22361
+author:
+type: fixed
diff --git a/doc/user/project/integrations/webhooks.md b/doc/user/project/integrations/webhooks.md
index 7d12cd8f7c2..02c18c7cbd7 100644
--- a/doc/user/project/integrations/webhooks.md
+++ b/doc/user/project/integrations/webhooks.md
@@ -73,8 +73,8 @@ Below are described the supported events.
 
 Triggered when you push to the repository except when pushing tags.
 
-> **Note:** When more than 20 commits are pushed at once, the `commits` web hook 
-  attribute will only contain the first 20 for performance reasons. Loading 
+> **Note:** When more than 20 commits are pushed at once, the `commits` web hook
+  attribute will only contain the first 20 for performance reasons. Loading
   detailed commit data is expensive. Note that despite only 20 commits being
   present in the `commits` attribute, the `total_commits_count` attribute will
   contain the actual total.
@@ -1157,10 +1157,11 @@ its description:
 ```
 
 It will appear in the webhook body as the below (assuming that GitLab is
-installed at gitlab.example.com):
+installed at gitlab.example.com, and the project is at
+example-group/example-project):
 
 ```markdown
-![image](https://gitlab.example.com/uploads/$sha/image.png)
+![image](https://gitlab.example.com/example-group/example-project/uploads/$sha/image.png)
 ```
 
 This will not rewrite URLs that already are pointing to HTTP, HTTPS, or
diff --git a/lib/gitlab/hook_data/base_builder.rb b/lib/gitlab/hook_data/base_builder.rb
index 4ffca356b29..1a91301e8be 100644
--- a/lib/gitlab/hook_data/base_builder.rb
+++ b/lib/gitlab/hook_data/base_builder.rb
@@ -25,6 +25,7 @@ module Gitlab
         markdown_text.gsub(MARKDOWN_SIMPLE_IMAGE) do
           if $~[:image]
             url = $~[:url]
+            url = "#{uploads_prefix}#{url}" if url.start_with?('/uploads')
             url = "/#{url}" unless url.start_with?('/')
 
             "![#{$~[:title]}](#{Gitlab.config.gitlab.url}#{url})"
@@ -33,6 +34,16 @@ module Gitlab
           end
         end
       end
+
+      def uploads_prefix
+        project&.full_path || ''
+      end
+
+      def project
+        return unless object.respond_to?(:project)
+
+        object.project
+      end
     end
   end
 end
diff --git a/spec/lib/gitlab/hook_data/base_builder_spec.rb b/spec/lib/gitlab/hook_data/base_builder_spec.rb
index a921dd766c3..e3c5ee3b905 100644
--- a/spec/lib/gitlab/hook_data/base_builder_spec.rb
+++ b/spec/lib/gitlab/hook_data/base_builder_spec.rb
@@ -8,57 +8,94 @@ describe Gitlab::HookData::BaseBuilder do
       end
     end
 
-    subject { subclass.new(nil) }
-
     using RSpec::Parameterized::TableSyntax
 
-    where do
-      {
-        'relative image URL' => {
-          input: '![an image](foo.png)',
-          output: "![an image](#{Gitlab.config.gitlab.url}/foo.png)"
-        },
-        'HTTP URL' => {
-          input: '![an image](http://example.com/foo.png)',
-          output: '![an image](http://example.com/foo.png)'
-        },
-        'HTTPS URL' => {
-          input: '![an image](https://example.com/foo.png)',
-          output: '![an image](https://example.com/foo.png)'
-        },
-        'protocol-relative URL' => {
-          input: '![an image](//example.com/foo.png)',
-          output: '![an image](//example.com/foo.png)'
-        },
-        'URL reference by title' => {
-          input: "![foo]\n\n[foo]: foo.png",
-          output: "![foo]\n\n[foo]: foo.png"
-        },
-        'URL reference by label' => {
-          input: "![][foo]\n\n[foo]: foo.png",
-          output: "![][foo]\n\n[foo]: foo.png"
-        },
-        'in Markdown inline code block' => {
-          input: '`![an image](foo.png)`',
-          output: "`![an image](#{Gitlab.config.gitlab.url}/foo.png)`"
-        },
-        'in HTML tag on the same line' => {
-          input: '<p>![an image](foo.png)</p>',
-          output: "<p>![an image](#{Gitlab.config.gitlab.url}/foo.png)</p>"
-        },
-        'in Markdown multi-line code block' => {
-          input: "```\n![an image](foo.png)\n```",
-          output: "```\n![an image](foo.png)\n```"
-        },
-        'in HTML tag on different lines' => {
-          input: "<p>\n![an image](foo.png)\n</p>",
-          output: "<p>\n![an image](foo.png)\n</p>"
+    context 'with an upload prefix specified' do
+      let(:project_with_path) { double(full_path: 'baz/bar') }
+      let(:object_with_project) { double(project: project_with_path) }
+      subject { subclass.new(object_with_project) }
+
+      where do
+        {
+          'relative image URL' => {
+            input: '![an image](foo.png)',
+            output: "![an image](#{Gitlab.config.gitlab.url}/foo.png)"
+          },
+          'absolute upload URL' => {
+            input: '![an image](/uploads/foo.png)',
+            output: "![an image](#{Gitlab.config.gitlab.url}/baz/bar/uploads/foo.png)"
+          },
+          'absolute non-upload URL' => {
+            input: '![an image](/downloads/foo.png)',
+            output: "![an image](#{Gitlab.config.gitlab.url}/downloads/foo.png)"
+          }
         }
-      }
+      end
+
+      with_them do
+        it { expect(subject.absolute_image_urls(input)).to eq(output) }
+      end
     end
 
-    with_them do
-      it { expect(subject.absolute_image_urls(input)).to eq(output) }
+    context 'without an upload prefix specified' do
+      subject { subclass.new(nil) }
+
+      where do
+        {
+          'relative image URL' => {
+            input: '![an image](foo.png)',
+            output: "![an image](#{Gitlab.config.gitlab.url}/foo.png)"
+          },
+          'absolute upload URL' => {
+            input: '![an image](/uploads/foo.png)',
+            output: "![an image](#{Gitlab.config.gitlab.url}/uploads/foo.png)"
+          },
+          'absolute non-upload URL' => {
+            input: '![an image](/downloads/foo.png)',
+            output: "![an image](#{Gitlab.config.gitlab.url}/downloads/foo.png)"
+          },
+          'HTTP URL' => {
+            input: '![an image](http://example.com/foo.png)',
+            output: '![an image](http://example.com/foo.png)'
+          },
+          'HTTPS URL' => {
+            input: '![an image](https://example.com/foo.png)',
+            output: '![an image](https://example.com/foo.png)'
+          },
+          'protocol-relative URL' => {
+            input: '![an image](//example.com/foo.png)',
+            output: '![an image](//example.com/foo.png)'
+          },
+          'URL reference by title' => {
+            input: "![foo]\n\n[foo]: foo.png",
+            output: "![foo]\n\n[foo]: foo.png"
+          },
+          'URL reference by label' => {
+            input: "![][foo]\n\n[foo]: foo.png",
+            output: "![][foo]\n\n[foo]: foo.png"
+          },
+          'in Markdown inline code block' => {
+            input: '`![an image](foo.png)`',
+            output: "`![an image](#{Gitlab.config.gitlab.url}/foo.png)`"
+          },
+          'in HTML tag on the same line' => {
+            input: '<p>![an image](foo.png)</p>',
+            output: "<p>![an image](#{Gitlab.config.gitlab.url}/foo.png)</p>"
+          },
+          'in Markdown multi-line code block' => {
+            input: "```\n![an image](foo.png)\n```",
+            output: "```\n![an image](foo.png)\n```"
+          },
+          'in HTML tag on different lines' => {
+            input: "<p>\n![an image](foo.png)\n</p>",
+            output: "<p>\n![an image](foo.png)\n</p>"
+          }
+        }
+      end
+
+      with_them do
+        it { expect(subject.absolute_image_urls(input)).to eq(output) }
+      end
     end
   end
 end
diff --git a/spec/lib/gitlab/hook_data/issue_builder_spec.rb b/spec/lib/gitlab/hook_data/issue_builder_spec.rb
index 60093474f8a..f066c0e3813 100644
--- a/spec/lib/gitlab/hook_data/issue_builder_spec.rb
+++ b/spec/lib/gitlab/hook_data/issue_builder_spec.rb
@@ -46,7 +46,10 @@ describe Gitlab::HookData::IssueBuilder do
       let(:builder) { described_class.new(issue_with_description) }
 
       it 'sets the image to use an absolute URL' do
-        expect(data[:description]).to eq("test![Issue_Image](#{Settings.gitlab.url}/uploads/abc/Issue_Image.png)")
+        expected_path = "#{issue_with_description.project.path_with_namespace}/uploads/abc/Issue_Image.png"
+
+        expect(data[:description])
+          .to eq("test![Issue_Image](#{Settings.gitlab.url}/#{expected_path})")
       end
     end
   end
diff --git a/spec/lib/gitlab/hook_data/merge_request_builder_spec.rb b/spec/lib/gitlab/hook_data/merge_request_builder_spec.rb
index dd586af6118..9ce697adbba 100644
--- a/spec/lib/gitlab/hook_data/merge_request_builder_spec.rb
+++ b/spec/lib/gitlab/hook_data/merge_request_builder_spec.rb
@@ -58,11 +58,14 @@ describe Gitlab::HookData::MergeRequestBuilder do
     end
 
     context 'when the MR has an image in the description' do
-      let(:mr_with_description) { create(:merge_request, description: 'test![Issue_Image](/uploads/abc/Issue_Image.png)') }
+      let(:mr_with_description) { create(:merge_request, description: 'test![MR_Image](/uploads/abc/MR_Image.png)') }
       let(:builder) { described_class.new(mr_with_description) }
 
       it 'sets the image to use an absolute URL' do
-        expect(data[:description]).to eq("test![Issue_Image](#{Settings.gitlab.url}/uploads/abc/Issue_Image.png)")
+        expected_path = "#{mr_with_description.project.path_with_namespace}/uploads/abc/MR_Image.png"
+
+        expect(data[:description])
+          .to eq("test![MR_Image](#{Settings.gitlab.url}/#{expected_path})")
       end
     end
   end