Add experimental JSON format for tree controller

app/controllers/projects/tree_controller.rb

@@ -24,12 +24,19 @@ class Projects::TreeController < Projects::ApplicationController
       end
     end
 
+    respond_to do |format|
+      format.html do
         @last_commit = @repository.last_commit_for_path(@commit.id, @tree.path) || @commit
+      end
 
-    respond_to do |format|
-      format.html
+      format.js do
         # Disable cache so browser history works
-      format.js { no_cache_headers }
+        no_cache_headers
+      end
+
+      format.json do
+        render json: TreeSerializer.new(project: @project, repository: @repository, ref: @ref).represent(@tree)
+      end
     end
   end
 

app/helpers/diff_helper.rb

@@ -88,15 +88,15 @@ module DiffHelper
   end
 
   def submodule_link(blob, ref, repository = @repository)
-    tree, commit = submodule_links(blob, ref, repository)
-    commit_id = if commit.nil?
+    project_url, tree_url = submodule_links(blob, ref, repository)
+    commit_id = if tree_url.nil?
                   Commit.truncate_sha(blob.id)
                 else
-                  link_to Commit.truncate_sha(blob.id), commit
+                  link_to Commit.truncate_sha(blob.id), tree_url
                 end
 
     [
-      content_tag(:span, link_to(truncate(blob.name, length: 40), tree)),
+      content_tag(:span, link_to(truncate(blob.name, length: 40), project_url)),
       '@',
       content_tag(:span, commit_id, class: 'commit-sha')
     ].join(' ').html_safe

app/helpers/icons_helper.rb

 module IconsHelper
+  extend self
   include FontAwesome::Rails::IconHelper
 
   # Creates an icon tag given icon name(s) and possible icon modifiers.

app/helpers/submodule_helper.rb

 module SubmoduleHelper
-  include Gitlab::ShellAdapter
+  extend self
 
   VALID_SUBMODULE_PROTOCOLS = %w[http https git ssh].freeze
 
@@ -47,7 +47,7 @@ module SubmoduleHelper
     return true if url_no_dotgit == [Gitlab.config.gitlab.url, '/', namespace, '/',
                                      project].join('')
     url_with_dotgit = url_no_dotgit + '.git'
-    url_with_dotgit == gitlab_shell.url_to_repo([namespace, '/', project].join(''))
+    url_with_dotgit == Gitlab::Shell.new.url_to_repo([namespace, '/', project].join(''))
   end
 
   def relative_self_url?(url)

app/serializers/blob_entity.rb

+class BlobEntity < Grape::Entity
+  include RequestAwareEntity
+
+  expose :id, :path, :name, :mode
+
+  expose :icon do |blob|
+    IconsHelper.file_type_icon_class('file', blob.mode, blob.name)
+  end
+
+  expose :url do |blob|
+    namespace_project_blob_path(request.project.namespace, request.project, File.join(request.ref, blob.path))
+  end
+end

app/serializers/submodule_entity.rb

+class SubmoduleEntity < Grape::Entity
+  include RequestAwareEntity
+
+  expose :id, :path, :name, :mode
+
+  expose :icon do |blob|
+    'archive'
+  end
+
+  expose :project_url do |blob|
+    submodule_links(blob, request).first
+  end
+
+  expose :tree_url do |blob|
+    submodule_links(blob, request).last
+  end
+
+  private
+
+  def submodule_links(blob, request)
+    @submodule_links ||= SubmoduleHelper.submodule_links(blob, request.ref, request.repository)
+  end
+end

app/serializers/tree_entity.rb

+class TreeEntity < Grape::Entity
+  include RequestAwareEntity
+
+  expose :id, :path, :name, :mode
+
+  expose :icon do |tree|
+    IconsHelper.file_type_icon_class('folder', tree.mode, tree.name)
+  end
+
+  expose :url do |tree|
+    namespace_project_tree_path(request.project.namespace, request.project, File.join(request.ref, tree.path))
+  end
+end

app/serializers/tree_root_entity.rb

+# TODO: Inherit from TreeEntity, when `Tree` implements `id` and `name` like `Gitlab::Git::Tree`.
+class TreeRootEntity < Grape::Entity
+  expose :path
+  
+  expose :trees, using: TreeEntity
+  expose :blobs, using: BlobEntity
+  expose :submodules, using: SubmoduleEntity
+end

app/serializers/tree_serializer.rb

+class TreeSerializer < BaseSerializer
+  entity TreeRootEntity
+end