Support other 'changes' for GitLab payloads

Author: colinodell

.github/workflows/workflow.yml

@@ -23,7 +23,7 @@ jobs:
     name: Test
     strategy:
       matrix:
-        go-version: [1.17.x, 1.18.x, 1.20.x]
+        go-version: [1.18.x, 1.20.x]
         os: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:

gitlab/payload.go

@@ -870,13 +870,36 @@ type Author struct {
 
 // Changes contains all changes associated with a GitLab issue or MR
 type Changes struct {
-	LabelChanges LabelChanges `json:"labels"`
+	LabelChanges *ListChange[Label]           `json:"labels"`
+	Draft        *PropChange[bool]            `json:"draft"`
+	StateId      *PropChange[IssuableStateID] `json:"state_id"`
+	Assignees    *ListChange[User]            `json:"assignees"`
+	Reviewers    *ListChange[User]            `json:"reviewers"`
+	Title        *PropChange[string]          `json:"title"`
+	Description  *PropChange[string]          `json:"description"`
+
+	UpdatedAt      *PropChange[customTime] `json:"updated_at"`
+	UpdatedByID    *PropChange[int64]      `json:"updated_by_id"`
+	LastEditedAt   *PropChange[customTime] `json:"last_edited_at"`
+	LastEditedByID *PropChange[int64]      `json:"last_edited_by_id"`
+}
+
+type PropChange[T comparable] struct {
+	Previous T `json:"previous"`
+	Current  T `json:"current"`
+}
+
+func (p *PropChange[T]) Was(value T) bool {
+	return p != nil && p.Previous == value
 }
 
-// LabelChanges contains changes in labels assocatiated with a GitLab issue or MR
-type LabelChanges struct {
-	Previous []Label `json:"previous"`
-	Current  []Label `json:"current"`
+func (p *PropChange[T]) Became(newValue T) bool {
+	return p != nil && p.Current == newValue
+}
+
+type ListChange[T comparable] struct {
+	Previous []T `json:"previous"`
+	Current  []T `json:"current"`
 }
 
 // Label contains all of the GitLab label information
@@ -892,3 +915,13 @@ type Label struct {
 	Type        string     `json:"type"`
 	GroupID     int64      `json:"group_id"`
 }
+
+type IssuableStateID int
+
+// Source: https://forum.gitlab.com/t/merge-event-state-id-meanings/47433
+const (
+	StateOpened IssuableStateID = 1
+	StateClosed IssuableStateID = 2
+	StateMerged IssuableStateID = 3
+	StateLocked IssuableStateID = 4
+)

go.mod

@@ -1,6 +1,6 @@
 module github.com/go-playground/webhooks/v6
 
-go 1.17
+go 1.18
 
 require (
 	github.com/gogits/go-gogs-client v0.0.0-20200905025246-8bb8a50cb355

testdata/gitlab/merge-request-event.json

@@ -133,10 +133,22 @@
     "group_id": 41
   }],
   "changes": {
+    "title": {
+      "previous": "MS Viewport",
+      "current": "MS-Viewport"
+    },
+    "description": {
+      "previous": "Lorem ipsum dolor sit amet",
+      "current": ""
+    },
     "updated_by_id": {
       "previous": null,
       "current": 1
     },
+    "draft": {
+      "previous": true,
+      "current": false
+    },
     "updated_at": {
       "previous": "2017-09-15 16:50:55 UTC",
       "current":"2017-09-15 16:52:00 UTC"
@@ -174,6 +186,28 @@
     "last_edited_by_id": {
       "previous": null,
       "current": 3278533
+    },
+    "assignees": {
+      "previous": [],
+      "current": [
+        {
+          "id": 6,
+          "name": "User1",
+          "username": "user1",
+          "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
+        }
+      ]
+    },
+    "reviewers": {
+      "previous": [],
+      "current": [
+        {
+          "id": 6,
+          "name": "User1",
+          "username": "user1",
+          "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
+        }
+      ]
     }
   },
   "assignees": [