notify user when role in group changed

backend/src/middleware/notifications/notificationsMiddleware.js

@@ -73,6 +73,17 @@ const handleLeaveGroup = async (resolve, root, args, context, resolveInfo) => {
   return user
 }
 
+const handleChangeGroupMemberRole = async (resolve, root, args, context, resolveInfo) => {
+  const { groupId, userId } = args
+  const user = await resolve(root, args, context, resolveInfo)
+  if (user) {
+    await publishNotifications(context, [
+      notifyMemberOfGroup(groupId, userId, 'changed_group_member_role', context),
+    ])
+  }
+  return user
+}
+
 const handleContentDataOfPost = async (resolve, root, args, context, resolveInfo) => {
   const idsOfUsers = extractMentionedUsers(args.content)
   const post = await resolve(root, args, context, resolveInfo)
@@ -148,6 +159,37 @@ const notifyOwnersOfGroup = async (groupId, userId, reason, context) => {
   }
 }
 
+const notifyMemberOfGroup = async (groupId, userId, reason, context) => {
+  const cypher = `
+    MATCH (group:Group { id: $groupId })<-[membership:MEMBER_OF]-(user:User { id: $userId })
+    WITH user, group
+    MERGE (group)-[notification:NOTIFIED {reason: $reason}]->(user)
+    WITH group, user, notification
+    SET notification.read = FALSE
+    SET notification.createdAt = COALESCE(notification.createdAt, toString(datetime()))
+    SET notification.updatedAt = toString(datetime())
+    SET notification.relatedUserId = $userId
+    RETURN notification {.*, from: group, to: properties(user)}
+  `
+  const session = context.driver.session()
+  const writeTxResultPromise = session.writeTransaction(async (transaction) => {
+    const notificationTransactionResponse = await transaction.run(cypher, {
+      groupId,
+      reason,
+      userId,
+    })
+    return notificationTransactionResponse.records.map((record) => record.get('notification'))
+  })
+  try {
+    const notifications = await writeTxResultPromise
+    return notifications
+  } catch (error) {
+    throw new Error(error)
+  } finally {
+    session.close()
+  }
+}
+
 const notifyUsersOfMention = async (label, id, idsOfUsers, reason, context) => {
   if (!(idsOfUsers && idsOfUsers.length)) return []
   await validateNotifyUsers(label, reason)
@@ -244,5 +286,6 @@ export default {
     UpdateComment: handleContentDataOfComment,
     JoinGroup: handleJoinGroup,
     LeaveGroup: handleLeaveGroup,
+    ChangeGroupMemberRole: handleChangeGroupMemberRole,
   },
 }

backend/src/middleware/notifications/notificationsMiddleware.spec.js

@@ -7,7 +7,7 @@ import {
   createGroupMutation,
   joinGroupMutation,
   leaveGroupMutation,
-  //  changeGroupMemberRoleMutation,
+  changeGroupMemberRoleMutation,
   //  removeUserFromGroupMutation,
 } from '../../graphql/groups'
 
@@ -763,5 +763,54 @@ describe('notifications', () => {
         })
       })
     })
+
+    describe('user role in group changes', () => {
+      beforeEach(async () => {
+        authenticatedUser = await notifiedUser.toJson()
+        await mutate({
+          mutation: joinGroupMutation(),
+          variables: {
+            groupId: 'closed-group',
+            userId: authenticatedUser.id,
+          },
+        })
+        authenticatedUser = await groupOwner.toJson()
+        await mutate({
+          mutation: changeGroupMemberRoleMutation(),
+          variables: {
+            groupId: 'closed-group',
+            userId: 'you',
+            roleInGroup: 'admin',
+          },
+        })
+        authenticatedUser = await notifiedUser.toJson()
+      })
+
+      it('has notification in database', async () => {
+        await expect(
+          query({
+            query: notificationQuery,
+          }),
+        ).resolves.toMatchObject({
+          data: {
+            notifications: [
+              {
+                read: false,
+                reason: 'changed_group_member_role',
+                createdAt: expect.any(String),
+                from: {
+                  __typename: 'Group',
+                  id: 'closed-group',
+                },
+                relatedUser: {
+                  id: 'you',
+                },
+              },
+            ],
+          },
+          errors: undefined,
+        })
+      })
+    })
   })
 })

backend/src/schema/types/type/NOTIFIED.gql

@@ -24,6 +24,7 @@ enum NotificationReason {
   commented_on_post
   user_joined_group
   user_left_group
+  changed_group_member_role
 }
 
 type Query {