feat: add comment feature

packages/server/schema.gql

@@ -10,11 +10,54 @@ type Organization {
   logoURL: String!
 }
 
+type UserModel {
+  id: ID!
+}
+
+type Comment {
+  _id: ID!
+  file: File!
+  parentId: ID
+  user: UserModel!
+  date: DateTime!
+  content: String!
+  replies: [Comment!]!
+}
+
+"""
+A date-time string at UTC, such as 2019-12-03T09:54:33Z, compliant with the date-time format.
+"""
+scalar DateTime
+
+type File {
+  _id: ID!
+  fileId: String!
+  bucket: String!
+  comments: [Comment!]!
+}
+
 type Query {
   getOriganizations: [Organization!]!
+  getFileByFileId(fileId: String!): File!
 }
 
 type Mutation {
+  addFile(input: CreateFileInput!): File!
+  deleteFile(fileId: String!): Boolean!
+  addComment(input: CreateCommentInput!): Comment!
+  deleteComment(id: String!): Boolean!
+
   """Create new JupyterNotebook for user"""
   nistGetJupterNotebook(fileURL: String!, fileName: String!): String!
+}
+
+input CreateFileInput {
+  fileId: String!
+  bucket: String!
+}
+
+input CreateCommentInput {
+  file: String!
+  parentId: String
+  content: String!
 }

packages/server/src/app.module.ts

@@ -7,6 +7,8 @@ import { MongooseModule } from '@nestjs/mongoose';
 import { ConfigModule, ConfigService } from '@nestjs/config';
 import { JupyterhubModule } from './jupyterhub/jupyterhub.module';
 import configuration from './config/configuration';
+import { FileModule } from './file/file.module';
+import { CommentModule } from './comment/comment.module';
 
 @Module({
   imports: [
@@ -30,8 +32,9 @@ import configuration from './config/configuration';
       inject: [ConfigService]
     }),
     OrganizationModule,
-    JupyterhubModule,
-    AuthModule
+    FileModule,
+    CommentModule,
+    JupyterhubModule
   ]
 })
 export class AppModule {}

packages/server/src/comment/comment.dto.ts

@@ -0,0 +1,13 @@
+import { Field, InputType } from '@nestjs/graphql';
+
+@InputType()
+export class CreateCommentInput {
+  @Field()
+  file: string;
+
+  @Field({ nullable: true })
+  parentId?: string;
+
+  @Field()
+  content: string;
+}

packages/server/src/comment/comment.model.ts

@@ -0,0 +1,49 @@
+import { Directive, Field, ID, ObjectType } from '@nestjs/graphql';
+import { Prop, Schema, SchemaFactory } from '@nestjs/mongoose';
+import mongoose, { Document } from 'mongoose';
+import { File } from 'src/file/file.model';
+
+@ObjectType()
+@Directive('@key(fields: "id")')
+@Directive('@extends')
+export class UserModel {
+  @Field(() => ID)
+  @Directive('@external')
+  id: string;
+}
+
+@Schema()
+@ObjectType()
+@Directive('@key(fields: "_id")')
+export class Comment {
+  @Field(() => ID)
+  _id: mongoose.Schema.Types.ObjectId;
+
+  // refer to fileId in file.model.ts, NOT _id
+  @Prop({ required: true })
+  @Field(() => File, { description: "UUID of the file which is fileId in file's model" })
+  file: string;
+
+  @Prop({ type: mongoose.Schema.Types.ObjectId, ref: 'Comment', required: false })
+  @Field(() => ID, { nullable: true })
+  parentId: mongoose.Schema.Types.ObjectId | null;
+
+  @Prop()
+  @Field(() => UserModel, { description: 'ID of the user from the Auth Microservice' })
+  user: string;
+
+  @Prop({ type: Date, required: true, default: Date.now })
+  @Field()
+  date: Date;
+
+  @Prop()
+  @Field()
+  content: string;
+
+  @Prop({ type: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Comment' }], default: [] })
+  @Field(() => [Comment])
+  replies: mongoose.Schema.Types.ObjectId[];
+}
+
+export type CommentDocument = Comment & Document;
+export const CommentSchema = SchemaFactory.createForClass(Comment);

packages/server/src/comment/comment.module.ts

@@ -0,0 +1,18 @@
+import { Module } from '@nestjs/common';
+import { MongooseModule } from '@nestjs/mongoose';
+import { Comment, CommentSchema } from './comment.model';
+import { CommentService } from './comment.service';
+import { CommentResolver } from './comment.resolver';
+import { File, FileSchema } from 'src/file/file.model';
+import { FileService } from 'src/file/file.service';
+
+@Module({
+  imports: [
+    MongooseModule.forFeature([
+      { name: Comment.name, schema: CommentSchema },
+      { name: File.name, schema: FileSchema }
+    ])
+  ],
+  providers: [CommentService, CommentResolver, FileService]
+})
+export class CommentModule {}

packages/server/src/comment/comment.resolver.ts

@@ -0,0 +1,41 @@
+import { Args, Mutation, Parent, ResolveField, Resolver } from '@nestjs/graphql';
+import { CommentService } from './comment.service';
+import { Comment, UserModel } from './comment.model';
+import { CreateCommentInput } from './comment.dto';
+import { UseGuards } from '@nestjs/common';
+import { JwtAuthGuard } from 'src/auth/jwt.guard';
+import { UserContext } from 'src/auth/user.decorator';
+import { TokenPayload } from 'src/auth/user.dto';
+import { FileService } from 'src/file/file.service';
+import { File } from 'src/file/file.model';
+
+@Resolver(() => Comment)
+@UseGuards(JwtAuthGuard)
+export class CommentResolver {
+  constructor(private commentService: CommentService, private fileService: FileService) {}
+
+  @Mutation(() => Comment)
+  async addComment(@UserContext() user: TokenPayload, @Args('input') input: CreateCommentInput): Promise<Comment> {
+    return this.commentService.create(input, user.id);
+  }
+
+  @Mutation(() => Boolean)
+  async deleteComment(@Args('id') id: string): Promise<boolean> {
+    return this.commentService.removeComment(id);
+  }
+
+  @ResolveField('replies', () => [Comment])
+  async getReplies(@Parent() comment: Comment): Promise<Comment[]> {
+    return this.commentService.findByIds(comment.replies);
+  }
+
+  @ResolveField('file', () => File, { nullable: true })
+  async getFile(@Parent() comment: Comment): Promise<File | null> {
+    return this.fileService.findByFileId(comment.file);
+  }
+
+  @ResolveField('user', () => UserModel)
+  resolveUser(@Parent() comment: Comment): any {
+    return { __typename: 'UserModel', id: comment.user };
+  }
+}

packages/server/src/comment/comment.service.ts

@@ -0,0 +1,41 @@
+import { Injectable } from '@nestjs/common';
+import { InjectModel } from '@nestjs/mongoose';
+import { Comment, CommentDocument } from './comment.model';
+import mongoose, { Model } from 'mongoose';
+import { CreateCommentInput } from './comment.dto';
+import { File, FileDocument } from 'src/file/file.model';
+
+@Injectable()
+export class CommentService {
+  constructor(
+    @InjectModel(Comment.name) private commentModel: Model<CommentDocument>,
+    @InjectModel(File.name) private fileModel: Model<FileDocument>
+  ) {}
+
+  async create(createCommentInput: CreateCommentInput, user: string): Promise<Comment> {
+    const newComment = new this.commentModel({ ...createCommentInput, user });
+    await newComment.save();
+
+    if (createCommentInput.parentId) {
+      await this.commentModel.updateOne({ _id: createCommentInput.parentId }, { $push: { replies: newComment._id } });
+    } else {
+      await this.fileModel.updateOne({ file: createCommentInput.file }, { $push: { comments: newComment._id } });
+    }
+
+    return newComment;
+  }
+
+  async findByIds(ids: mongoose.Schema.Types.ObjectId[]): Promise<Comment[]> {
+    return this.commentModel.find({ _id: { $in: ids } }).exec();
+  }
+
+  async findByFile(file: string): Promise<Comment[]> {
+    return this.commentModel.find({ file, parentId: null }).exec();
+  }
+
+  async removeComment(id: string): Promise<boolean> {
+    await this.commentModel.deleteMany({ parentId: id }).exec();
+    const deleted = await this.commentModel.findByIdAndDelete(id).exec();
+    return !!deleted;
+  }
+}

packages/server/src/file/file.dto.ts

@@ -0,0 +1,10 @@
+import { Field, ID, InputType } from '@nestjs/graphql';
+
+@InputType()
+export class CreateFileInput {
+  @Field()
+  fileId: string;
+
+  @Field()
+  bucket: string;
+}

packages/server/src/file/file.model.ts

@@ -0,0 +1,29 @@
+import { Directive, Field, ID, ObjectType } from '@nestjs/graphql';
+import { Prop, Schema, SchemaFactory } from '@nestjs/mongoose';
+import mongoose, { Document } from 'mongoose';
+import { Comment } from 'src/comment/comment.model';
+
+@Schema()
+@ObjectType()
+@Directive('@key(fields: "_id")')
+export class File {
+  @Field(() => ID)
+  _id: mongoose.Schema.Types.ObjectId;
+
+  // File's UUID is generated by the s3 viewer plugin. It is stored in the S3 object's metadata.
+  // UUID is too long to put in MongoDB's _id field, so we store it in a separate field.
+  @Prop()
+  @Field()
+  fileId: string;
+
+  @Prop()
+  @Field()
+  bucket: string;
+
+  @Prop({ type: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Comment' }], default: [] })
+  @Field(() => [Comment], { nullable: true })
+  comments: mongoose.Schema.Types.ObjectId[];
+}
+
+export type FileDocument = File & Document;
+export const FileSchema = SchemaFactory.createForClass(File);

packages/server/src/file/file.module.ts

@@ -0,0 +1,18 @@
+import { Module } from '@nestjs/common';
+import { MongooseModule } from '@nestjs/mongoose';
+import { File, FileSchema } from './file.model';
+import { FileService } from './file.service';
+import { FileResolver } from './file.resolver';
+import { Comment, CommentSchema } from 'src/comment/comment.model';
+import { CommentService } from 'src/comment/comment.service';
+
+@Module({
+  imports: [
+    MongooseModule.forFeature([
+      { name: File.name, schema: FileSchema },
+      { name: Comment.name, schema: CommentSchema }
+    ])
+  ],
+  providers: [FileService, FileResolver, CommentService]
+})
+export class FileModule {}

packages/server/src/file/file.resolver.ts

@@ -0,0 +1,34 @@
+import { Args, Mutation, Parent, Query, ResolveField, Resolver } from '@nestjs/graphql';
+import { FileService } from './file.service';
+import { File } from './file.model';
+import { CreateFileInput } from './file.dto';
+import { UseGuards } from '@nestjs/common';
+import { JwtAuthGuard } from 'src/auth/jwt.guard';
+import { Comment } from 'src/comment/comment.model';
+import { CommentService } from 'src/comment/comment.service';
+
+@Resolver(() => File)
+@UseGuards(JwtAuthGuard)
+export class FileResolver {
+  constructor(private fileService: FileService, private commentService: CommentService) {}
+
+  @Query(() => File, { nullable: true })
+  async getFileByFileId(@Args('fileId') fileId: string): Promise<File | null> {
+    return this.fileService.findByFileId(fileId);
+  }
+
+  @Mutation(() => File)
+  async addFile(@Args('input') input: CreateFileInput): Promise<File> {
+    return this.fileService.create(input);
+  }
+
+  @Mutation(() => Boolean)
+  async deleteFile(@Args('fileId') fileId: string): Promise<boolean> {
+    return this.fileService.removeFile(fileId);
+  }
+
+  @ResolveField('comments', () => [Comment])
+  async getComments(@Parent() file: File): Promise<Comment[]> {
+    return this.commentService.findByFile(file.fileId);
+  }
+}

packages/server/src/file/file.service.ts

@@ -0,0 +1,29 @@
+import { Injectable } from '@nestjs/common';
+import { InjectModel } from '@nestjs/mongoose';
+import { File, FileDocument } from './file.model';
+import { Model } from 'mongoose';
+import { CreateFileInput } from './file.dto';
+import { Comment, CommentDocument } from 'src/comment/comment.model';
+
+@Injectable()
+export class FileService {
+  constructor(
+    @InjectModel(File.name) private fileModel: Model<FileDocument>,
+    @InjectModel(Comment.name) private commentModel: Model<CommentDocument>
+  ) {}
+
+  async create(createFileInput: CreateFileInput): Promise<File> {
+    const createFile = new this.fileModel(createFileInput);
+    return createFile.save();
+  }
+
+  findByFileId(id: string): Promise<File | null> {
+    return this.fileModel.findOne({ fileId: id }).exec();
+  }
+
+  async removeFile(id: string): Promise<boolean> {
+    await this.commentModel.deleteMany({ fileId: id }).exec();
+    const deleted = await this.fileModel.findOneAndDelete({ fileId: id }).exec();
+    return !!deleted;
+  }
+}