Reduce the number of SQL requests on MR-show

- Extract MR fields for notes into a separate serializer
- Check if pipelines are empty via count

3 files changed, 31 insertions, 8 deletions

diff --git a/spec/fixtures/api/schemas/entities/merge_request_noteable.json b/spec/fixtures/api/schemas/entities/merge_request_noteable.json
new file mode 100644
index 00000000000..88b0fecc24c
--- /dev/null
+++ b/spec/fixtures/api/schemas/entities/merge_request_noteable.json
@@ -0,0 +1,28 @@
+{
+  "type": "object",
+  "properties" : {
+    "merge_params": { "type": ["object", "null"] },
+    "state": { "type": "string" },
+    "source_branch": { "type": "string" },
+    "target_branch": { "type": "string" },
+    "diff_head_sha": { "type": "string" },
+    "create_note_path": { "type": ["string", "null"] },
+    "preview_note_path": { "type": ["string", "null"] },
+    "create_issue_to_resolve_discussions_path": { "type": ["string", "null"] },
+    "new_blob_path": { "type": ["string", "null"] },
+    "can_receive_suggestion": { "type": "boolean" },
+    "current_user": {
+      "type": "object",
+      "required": [
+        "can_create_note",
+        "can_update"
+      ],
+      "properties": {
+        "can_create_note": { "type": "boolean" },
+        "can_update": { "type": "boolean" }
+      },
+      "additionalProperties": false
+    }
+  },
+  "additionalProperties": false
+}
diff --git a/spec/fixtures/api/schemas/entities/merge_request_poll_widget.json b/spec/fixtures/api/schemas/entities/merge_request_poll_widget.json
index 2052892dfa3..1eda0e12920 100644
--- a/spec/fixtures/api/schemas/entities/merge_request_poll_widget.json
+++ b/spec/fixtures/api/schemas/entities/merge_request_poll_widget.json
@@ -24,22 +24,20 @@
     "ci_status": { "type": ["string", "null"] },
     "cancel_auto_merge_path": { "type": ["string", "null"] },
     "test_reports_path": { "type": ["string", "null"] },
-    "can_receive_suggestion": { "type": "boolean" },
     "create_issue_to_resolve_discussions_path": { "type": ["string", "null"] },
     "current_user": {
       "type": "object",
       "required": [
         "can_remove_source_branch",
         "can_revert_on_current_merge_request",
-        "can_cherry_pick_on_current_merge_request"
+        "can_cherry_pick_on_current_merge_request",
+        "can_create_issue"
       ],
       "properties": {
         "can_remove_source_branch": { "type": "boolean" },
         "can_revert_on_current_merge_request": { "type": ["boolean", "null"] },
         "can_cherry_pick_on_current_merge_request": { "type": ["boolean", "null"] },
-        "can_create_note": { "type": "boolean" },
-        "can_create_issue": { "type": "boolean" },
-        "can_update": { "type": "boolean" }
+        "can_create_issue": { "type": "boolean" }
       },
       "additionalProperties": false
     },
diff --git a/spec/fixtures/api/schemas/entities/merge_request_widget.json b/spec/fixtures/api/schemas/entities/merge_request_widget.json
index 779a47222b7..e2df7952d8f 100644
--- a/spec/fixtures/api/schemas/entities/merge_request_widget.json
+++ b/spec/fixtures/api/schemas/entities/merge_request_widget.json
@@ -5,7 +5,6 @@
     { "$ref": "merge_request_poll_widget.json" },
     {
       "properties" : {
-        "merge_params": { "type": ["object", "null"] },
         "source_project_full_path": { "type": ["string", "null"]},
         "target_project_full_path": { "type": ["string", "null"]},
         "email_patches_path": { "type": "string" },
@@ -13,9 +12,7 @@
         "merge_request_basic_path": { "type": "string" },
         "merge_request_widget_path": { "type": "string" },
         "merge_request_cached_widget_path": { "type": "string" },
-        "create_note_path": { "type": ["string", "null"] },
         "commit_change_content_path": { "type": "string" },
-        "preview_note_path": { "type": ["string", "null"] },
         "conflicts_docs_path": { "type": ["string", "null"] },
         "merge_request_pipelines_docs_path": { "type": ["string", "null"] },
         "ci_environments_status_path": { "type": "string" },