Merge pull request #291 from coralproject/recent-items

Added new recentComments, recentReplies

graph/loaders/comments.js

@@ -1,4 +1,5 @@
 const util = require('./util');
+const DataLoader = require('dataloader');
 
 const CommentModel = require('../../models/comment');
 
@@ -135,6 +136,95 @@ const getCommentsByQuery = ({user}, {ids, statuses, asset_id, parent_id, author_
     .limit(limit);
 };
 
+const genRecentReplies = (_, ids) => {
+  return CommentModel.aggregate([
+
+    // get all the replies for the comments in question
+    {$match: {
+      parent_id: {
+        $in: ids
+      }
+    }},
+
+    // sort these by their created at timestamp, CHRONOLOGICAL'y as these are
+    // replies
+    {$sort: {
+      created_at: 1
+    }},
+
+    // group these replies by their parent_id
+    {$group: {
+      _id: '$parent_id',
+      replies: {
+        $push: '$$ROOT'
+      }
+    }},
+
+    // project it so that we only retain the first 3 replies of each parent
+    // comment
+    {$project: {
+      _id: '$_id',
+      replies: {
+        $slice: [
+          '$replies',
+          0,
+          3
+        ]
+      }
+    }},
+
+    {$unwind: '$replies'},
+
+  ])
+  .then((replies) => replies.map((reply) => reply.replies))
+  .then(util.arrayJoinBy(ids, 'parent_id'));
+};
+
+const genRecentComments = (_, ids) => {
+  return CommentModel.aggregate([
+
+    // get all the replies for the comments in question
+    {$match: {
+      asset_id: {
+        $in: ids
+      }
+    }},
+
+    // sort these by their created at timestamp, CHRONOLOGICAL'y as these are
+    // replies
+    {$sort: {
+      created_at: 1
+    }},
+
+    // group these replies by their parent_id
+    {$group: {
+      _id: '$asset_id',
+      comments: {
+        $push: '$$ROOT'
+      }
+    }},
+
+    // project it so that we only retain the first 3 replies of each parent
+    // comment
+    {$project: {
+      _id: '$_id',
+      comments: {
+        $slice: [
+          '$comments',
+          0,
+          3
+        ]
+      }
+    }},
+
+    // Unwind these comments.
+    {$unwind: '$comments'},
+
+  ])
+  .then((replies) => replies.map((reply) => reply.comments))
+  .then(util.arrayJoinBy(ids, 'asset_id'));
+};
+
 /**
  * Creates a set of loaders based on a GraphQL context.
  * @param  {Object} context the context of the GraphQL request
@@ -144,6 +234,8 @@ module.exports = (context) => ({
   Comments: {
     getByQuery: (query) => getCommentsByQuery(context, query),
     countByAssetID: new util.SharedCacheDataLoader('Comments.countByAssetID', 3600, (ids) => getCountsByAssetID(context, ids)),
-    countByParentID: new util.SharedCacheDataLoader('Comments.countByParentID', 3600, (ids) => getCountsByParentID(context, ids))
+    countByParentID: new util.SharedCacheDataLoader('Comments.countByParentID', 3600, (ids) => getCountsByParentID(context, ids)),
+    genRecentReplies: new DataLoader((ids) => genRecentReplies(context, ids)),
+    genRecentComments: new DataLoader((ids) => genRecentComments(context, ids))
   }
 });

graph/resolvers/asset.js

@@ -1,4 +1,7 @@
 const Asset = {
+  recentComments({id}, _, {loaders: {Comments}}) {
+    return Comments.genRecentComments.load(id);
+  },
   comments({id}, {sort, limit}, {loaders: {Comments}}) {
     return Comments.getByQuery({
       asset_id: id,

graph/resolvers/comment.js

@@ -2,6 +2,9 @@ const Comment = {
   user({author_id}, _, {loaders: {Users}}) {
     return Users.getByID.load(author_id);
   },
+  recentReplies({id}, _, {loaders: {Comments}}) {
+    return Comments.genRecentReplies.load(id);
+  },
   replies({id, asset_id}, {sort, limit}, {loaders: {Comments}}) {
     return Comments.getByQuery({
       asset_id,

graph/typeDefs.graphql

@@ -72,6 +72,9 @@ type Comment {
   # the user who authored the comment.
   user: User
 
+  # the recent replies made against this comment.
+  recentReplies: [Comment]
+
   # the replies that were made to the comment.
   replies(sort: SORT_ORDER = CHRONOLOGICAL, limit: Int = 3): [Comment]
 
@@ -148,6 +151,9 @@ type Asset {
   # The URL that the asset is located on.
   url: String
 
+  # Returns recent comments
+  recentComments: [Comment]
+
   # The top level comments that are attached to the asset.
   comments(sort: SORT_ORDER = REVERSE_CHRONOLOGICAL, limit: Int = 10): [Comment]