DataAccess changes

- changed data access structure
- changed graphql schema
- changed create-tables sql script (added vote_type to votes table)

src/app.ts

@@ -2,7 +2,7 @@ import * as express from "express";
 import * as http from "http";
 import * as path from "path";
 import * as socketIo from "socket.io";
-import {DTO} from "./lib/DTO";
+import dataaccess from "./lib/dataaccess";
 import globals from "./lib/globals";
 import routes from "./routes";
 
@@ -10,20 +10,18 @@ class App {
     public app: express.Application;
     public io: socketIo.Server;
     public server: http.Server;
-    public dto: DTO;
 
     constructor() {
         this.app = express();
         this.server = new http.Server(this.app);
         this.io = socketIo(this.server);
-        this.dto = new DTO();
     }
 
     /**
      * initializes everything that needs to be initialized asynchronous.
      */
     public async init() {
-        await this.dto.init();
+        await dataaccess.init();
         await routes.ioListeners(this.io);
         this.app.set("views", path.join(__dirname, "views"));
         this.app.set("view engine", "pug");

src/lib/dataaccess/DataObject.ts

@@ -0,0 +1,14 @@
+abstract class DataObject {
+    protected dataLoaded: boolean = false;
+
+    constructor(public id: number, protected row?: any) {
+    }
+
+    protected abstract loadData(): Promise<void>;
+
+    protected loadDataIfNotExists() {
+        if (this.dataLoaded) {
+            this.loadData();
+        }
+    }
+}

src/lib/dataaccess/Post.ts

@@ -0,0 +1,101 @@
+import {queryHelper, VoteType} from "./index";
+import {User} from "./User";
+
+export class Post extends DataObject {
+    public readonly id: number;
+    private $upvotes: number;
+    private $downvotes: number;
+    private $createdAt: string;
+    private $content: string;
+    private $author: number;
+    private $type: string;
+
+    /**
+     * Returns the upvotes of a post.
+     */
+    public async upvotes(): Promise<number> {
+        this.loadDataIfNotExists();
+        return this.$upvotes;
+    }
+
+    /**
+     * Returns the downvotes of the post
+     */
+    public async downvotes(): Promise<number> {
+        this.loadDataIfNotExists();
+        return this.$downvotes;
+    }
+
+    /**
+     * The content of the post (markdown)
+     */
+    public async content(): Promise<string> {
+        this.loadDataIfNotExists();
+        return this.$content;
+    }
+
+    /**
+     * The date the post was created at.
+     */
+    public async createdAt(): Promise<string> {
+        this.loadDataIfNotExists();
+        return this.$createdAt;
+    }
+
+    /**
+     * The autor of the post.
+     */
+    public async author(): Promise<User> {
+        this.loadDataIfNotExists();
+        return new User(this.$author);
+    }
+
+    /**
+     * Deletes the post.
+     */
+    public async delete(): Promise<void> {
+        const query = await queryHelper.first({
+            text: "DELETE FROM posts WHERE id = $1",
+            values: [this.id],
+        });
+    }
+
+    /**
+     * The type of vote the user performed on the post.
+     */
+    public async userVote(userId: number): Promise<VoteType> {
+        const result = await queryHelper.first({
+            text: "SELECT vote_type FROM votes WHERE user_id = $1 AND item_id = $2",
+            values: [userId, this.id],
+        });
+        if (result) {
+            return result.vote_type;
+        } else {
+            return null;
+        }
+    }
+
+    /**
+     * Loads the data from the database if needed.
+     */
+    protected async loadData(): Promise<void> {
+        let result: any;
+        if (this.row) {
+            result = this.row;
+        } else {
+            result = await queryHelper.first({
+                text: "SELECT * FROM posts WHERE posts.id = $1",
+                values: [this.id],
+            });
+        }
+        if (result) {
+            this.$author = result.author;
+            this.$content = result.content;
+            this.$downvotes = result.downvotes;
+            this.$upvotes = result.upvotes;
+            this.$createdAt = result.created_at;
+            this.$type = result.type;
+            this.dataLoaded = true;
+        }
+    }
+}

src/lib/dataaccess/User.ts

@@ -0,0 +1,136 @@
+import {queryHelper} from "./index";
+import {Post} from "./Post";
+
+export class User extends DataObject {
+    private $name: string;
+    private $handle: string;
+    private $email: string;
+    private $greenpoints: number;
+    private $joinedAt: string;
+
+    /**
+     * The name of the user
+     */
+    public async name(): Promise<string> {
+        this.loadDataIfNotExists();
+        return this.$name;
+    }
+
+    /**
+     * Sets the username of the user
+     * @param name
+     */
+    public async setName(name: string): Promise<string> {
+        const result = await queryHelper.first({
+            text: "UPDATE TABLE users SET name = $1 WHERE id = $2",
+            values: [name, this.id],
+        });
+        return result.name;
+    }
+
+    /**
+     * The unique handle of the user.
+     */
+    public async handle(): Promise<string> {
+        this.loadDataIfNotExists();
+        return this.$handle;
+    }
+
+    /**
+     * Updates the handle of the user
+     */
+    public async setHandle(handle: string): Promise<string> {
+        const result = await queryHelper.first({
+            text: "UPDATE TABLE users SET handle = $1 WHERE id = $2",
+            values: [handle, this.id],
+        });
+        return result.handle;
+    }
+
+    /**
+     * The email of the user
+     */
+    public async email(): Promise<string> {
+        this.loadDataIfNotExists();
+        return this.$email;
+    }
+
+    /**
+     * Sets the email of the user
+     * @param email
+     */
+    public async setEmail(email: string): Promise<string> {
+        const result = await queryHelper.first({
+            text: "UPDATE TABLE users SET email = $1 WHERE users.id = $2 RETURNING email",
+            values: [email, this.id],
+        });
+        return result.email;
+    }
+
+    /**
+     * The number of greenpoints of the user
+     */
+    public async greenpoints(): Promise<number> {
+        this.loadDataIfNotExists();
+        return this.$greenpoints;
+    }
+
+    /**
+     * Sets the greenpoints of a user.
+     * @param points
+     */
+    public async setGreenpoints(points: number): Promise<number> {
+        const result = await queryHelper.first({
+            text: "UPDATE users SET greenpoints = $1 WHERE id = $2 RETURNING greenpoints",
+            values: [points, this.id],
+        });
+        return result.greenpoints;
+    }
+
+    /**
+     * The date the user joined the platform
+     */
+    public async joinedAt(): Promise<Date> {
+        this.loadDataIfNotExists();
+        return new Date(this.$joinedAt);
+    }
+
+    /**
+     * Returns all posts for a user.
+     */
+    public async posts(): Promise<Post[]> {
+        const result = await queryHelper.all({
+            text: "SELECT * FROM posts WHERE author = $1",
+            values: [this.id],
+        });
+        const posts = [];
+
+        for (const row of result) {
+            posts.push(new Post(row.id, row));
+        }
+        return posts;
+    }
+
+    /**
+     * Fetches the data for the user.
+     */
+    protected async loadData(): Promise<void> {
+        let result: any;
+        if (this.row) {
+            result = this.row;
+        } else {
+            result = await queryHelper.first({
+                text: "SELECT * FROM users WHERE user.id = $1",
+                values: [this.id],
+            });
+        }
+        if (result) {
+            this.$name = result.name;
+            this.$handle = result.handle;
+            this.$email = result.email;
+            this.$greenpoints = result.greenpoints;
+            this.$joinedAt = result.joined_at;
+            this.dataLoaded = true;
+        }
+    }
+}

src/lib/dataaccess/index.ts

@@ -1,7 +1,7 @@
 import {Runtime} from "inspector";
 import {Pool} from "pg";
-import globals from "./globals";
+import globals from "../globals";
-import {QueryHelper} from "./QueryHelper";
+import {QueryHelper} from "../QueryHelper";
 
 const config = globals.config;
 const tableCreationFile = __dirname + "/../sql/create-tables.sql";

src/public/graphql/schema.graphql

@@ -1,14 +1,19 @@
 type Query {
     "returns the user object for a given user id"
     getUser(userId: ID): User
+
     "returns the post object for a post id"
     getPost(postId: ID): Post
+
     "returns the chat object for a chat id"
     getChat(chatId: ID): ChatRoom
+
     "returns the request object for a request id"
     getRequest(requestId: ID): Request
+
     "find a post by the posted date or content"
     findPost(first: Int, offset: Int, text: String!, postedDate: String): [Post]
+
     "find a user by user name or handle"
     findUser(first: Int, offset: Int, name: String!, handle: String!): [User]
 }
@@ -16,34 +21,48 @@ type Query {
 type Mutation {
     "Upvote/downvote a Post"
     vote(postId: ID!, type: [VoteType!]!): Boolean
+
     "Report the post"
     report(postId: ID!): Boolean
+
     "lets you accept a request for a given request id"
     acceptRequest(requestId: ID!): Boolean
+
     "send a message in a Chatroom"
     sendMessage(chatId: ID!, content: String!): Boolean
+
+	# TODO: createPost, deletePost, sendRequest, denyRequest
 }
 
 "represents a single user account"
 type User {
     "url for the Profile picture of the User"
     profilePicture: String!
+
     "name of the User"
     name: String!
+
     "unique identifier name from the User"
     handle: String!
+
     "Id of the User"
     id: ID!
+
     "the total number of posts the user posted"
     numberOfPosts: Int
+
     "returns a given number of posts of a user"
     getAllPosts(first: Int=10, offset: Int): [Post]
+
     "creation date of the user account"
     joinedDate: String!
+
     "returns chats the user pinned"
     pinnedChats: [ChatRoom]
+
     "returns all friends of the user"
     friends: [User]
+
     "all request for groupChats/friends/events"
     requests: [Request]
 }
@@ -52,18 +71,25 @@ type User {
 type Post {
     "returns the path to the posts picture if it has one"
     picture: String
+
     "returns the text of the post"
     text: String
+
     "upvotes of the Post"
     upvotes: Int!
+
     "downvotes of the Post"
     downvotes: Int!
+
     "the user that is the author of the Post"
     author: User!
+
     "date the post was created"
     creationDate: String!
+
     "returns the type of vote the user performed on the post"
-	alreadyVoted: VoteType
+    userVote: VoteType
+
     "returns the tags of the post"
     tags: [String]
 }
@@ -72,6 +98,7 @@ type Post {
 type Request {
     "id of the request"
     id: ID!
+
     "type of the request"
     requestType: RequestType!
 }
@@ -80,8 +107,10 @@ type Request {
 type ChatRoom {
     "the members of the chatroom"
     members: [User!]
+
     "return a specfic range of messages posted in the chat"
     getMessages(first: Int, offset: Int): [String]
+
     "id of the chat"
     id: ID!
 }

src/sql/create-tables.sql

@@ -20,7 +20,8 @@ CREATE TABLE IF NOT EXISTS posts (
 
 CREATE TABLE IF NOT EXISTS votes (
     user_id SERIAL REFERENCES users (id) ON DELETE CASCADE,
-    item_id BIGSERIAL REFERENCES posts (id) ON DELETE CASCADE
+    item_id BIGSERIAL REFERENCES posts (id) ON DELETE CASCADE,
+    vote_type varchar(8) DEFAULT 1
 );
 
 CREATE TABLE IF NOT EXISTS events (