Merge branch '35942_api_binary_encoding' into 'master'

API fix for non UTF-8 data

Closes #35942

See merge request !14038

5 files changed, 38 insertions, 12 deletions

diff --git a/lib/api/commits.rb b/lib/api/commits.rb
index ea78737288a..4b8d248f5f7 100644
--- a/lib/api/commits.rb
+++ b/lib/api/commits.rb
@@ -104,7 +104,7 @@ module API
 
         not_found! 'Commit' unless commit
 
-        commit.raw_diffs.to_a
+        present commit.raw_diffs.to_a, with: Entities::RepoDiff
       end
 
       desc "Get a commit's comments" do
diff --git a/lib/api/entities.rb b/lib/api/entities.rb
index 9114b69606b..1d224d7bc21 100644
--- a/lib/api/entities.rb
+++ b/lib/api/entities.rb
@@ -291,10 +291,11 @@ module API
     end
 
     class RepoDiff < Grape::Entity
-      expose :old_path, :new_path, :a_mode, :b_mode, :diff
+      expose :old_path, :new_path, :a_mode, :b_mode
       expose :new_file?, as: :new_file
       expose :renamed_file?, as: :renamed_file
       expose :deleted_file?, as: :deleted_file
+      expose :json_safe_diff, as: :diff
     end
 
     class ProtectedRefAccess < Grape::Entity
diff --git a/lib/gitlab/encoding_helper.rb b/lib/gitlab/encoding_helper.rb
index 8ddc91e341d..7b3483a7f96 100644
--- a/lib/gitlab/encoding_helper.rb
+++ b/lib/gitlab/encoding_helper.rb
@@ -22,10 +22,10 @@ module Gitlab
 
       # return message if message type is binary
       detect = CharlockHolmes::EncodingDetector.detect(message)
-      return message.force_encoding("BINARY") if detect && detect[:type] == :binary
+      return message.force_encoding("BINARY") if detect_binary?(message, detect)
 
-      # force detected encoding if we have sufficient confidence.
       if detect && detect[:encoding] && detect[:confidence] > ENCODING_CONFIDENCE_THRESHOLD
+        # force detected encoding if we have sufficient confidence.
         message.force_encoding(detect[:encoding])
       end
 
@@ -36,6 +36,19 @@ module Gitlab
       "--broken encoding: #{encoding}"
     end
 
+    def detect_binary?(data, detect = nil)
+      detect ||= CharlockHolmes::EncodingDetector.detect(data)
+      detect && detect[:type] == :binary && detect[:confidence] == 100
+    end
+
+    def detect_libgit2_binary?(data)
+      # EncodingDetector checks the first 1024 * 1024 bytes for NUL byte, libgit2 checks
+      # only the first 8000 (https://github.com/libgit2/libgit2/blob/2ed855a9e8f9af211e7274021c2264e600c0f86b/src/filter.h#L15),
+      # which is what we use below to keep a consistent behavior.
+      detect = CharlockHolmes::EncodingDetector.new(8000).detect(data)
+      detect && detect[:type] == :binary
+    end
+
     def encode_utf8(message)
       detect = CharlockHolmes::EncodingDetector.detect(message)
       if detect && detect[:encoding]
diff --git a/lib/gitlab/git/blob.rb b/lib/gitlab/git/blob.rb
index 7780f4e4d4f..8d96826f6ee 100644
--- a/lib/gitlab/git/blob.rb
+++ b/lib/gitlab/git/blob.rb
@@ -42,14 +42,6 @@ module Gitlab
           end
         end
 
-        def binary?(data)
-          # EncodingDetector checks the first 1024 * 1024 bytes for NUL byte, libgit2 checks
-          # only the first 8000 (https://github.com/libgit2/libgit2/blob/2ed855a9e8f9af211e7274021c2264e600c0f86b/src/filter.h#L15),
-          # which is what we use below to keep a consistent behavior.
-          detect = CharlockHolmes::EncodingDetector.new(8000).detect(data)
-          detect && detect[:type] == :binary
-        end
-
         # Returns an array of Blob instances, specified in blob_references as
         # [[commit_sha, path], [commit_sha, path], ...]. If blob_size_limit < 0 then the
         # full blob contents are returned. If blob_size_limit >= 0 then each blob will
@@ -65,6 +57,10 @@ module Gitlab
           end
         end
 
+        def binary?(data)
+          EncodingHelper.detect_libgit2_binary?(data)
+        end
+
         private
 
         # Recursive search of blob id by path
diff --git a/lib/gitlab/git/diff.rb b/lib/gitlab/git/diff.rb
index ce3d65062e8..a23c8cf0dd1 100644
--- a/lib/gitlab/git/diff.rb
+++ b/lib/gitlab/git/diff.rb
@@ -116,6 +116,15 @@ module Gitlab
 
           filtered_opts
         end
+
+        # Return a binary diff message like:
+        #
+        # "Binary files a/file/path and b/file/path differ\n"
+        # This is used when we detect that a diff is binary
+        # using CharlockHolmes when Rugged treats it as text.
+        def binary_message(old_path, new_path)
+          "Binary files #{old_path} and #{new_path} differ\n"
+        end
       end
 
       def initialize(raw_diff, expanded: true)
@@ -190,6 +199,13 @@ module Gitlab
         @collapsed = true
       end
 
+      def json_safe_diff
+        return @diff unless detect_binary?(@diff)
+
+        # the diff is binary, let's make a message for it
+        Diff.binary_message(@old_path, @new_path)
+      end
+
       private
 
       def init_from_rugged(rugged)