Got basic query endpoint.

client/src/api.ts

@@ -7,14 +7,51 @@
 // a request structure, a response structure and
 // a checking function which determines request validity.
 
-// Query for songs.
+// Query for songs (POST).
 export const QuerySongsEndpoint = '/song/query';
-export interface QuerySongsRequest {}
+export enum SongQueryElemOp {
+    And = "AND",
+    Or = "OR",
+}
+export enum SongQueryFilterOp {
+    Eq = "EQ",
+    Ne = "NE",
+    In = "IN",
+    NotIn = "NOTIN"
+}
+export enum SongQueryElemProperty {
+    id = "id",
+    artistIds = "artistIds",
+    albumIds = "albumIds"
+}
+export interface SongQueryElem {
+    prop?: SongQueryElemProperty,
+    propOperand?: any,
+    propOperator?: SongQueryFilterOp,
+    children?: SongQueryElem[]
+    childrenOperator?: SongQueryElemOp,
+}
+export interface SongQuery extends SongQueryElem {}
+export interface QuerySongsRequest {
+    query: SongQuery
+}
 export interface QuerySongsResponse {
     ids: Number[]
 }
+export function checkQuerySongsElem(elem:any): boolean {
+    if(elem.childrenOperator && elem.children) {
+        elem.children.forEach((child:any) => {
+            if(!checkQuerySongsElem(child)) {
+                return false;
+            }
+        });
+    }
+    return (elem.childrenOperator && elem.children) ||
+    (elem.prop && elem.propOperand && elem.propOperator) ||
+    Object.keys(elem).length == 0;
+}
 export function checkQuerySongsRequest(req:any): boolean {
-    return true;
+    return "query" in req && checkQuerySongsElem(req.query);
 }
 
 // Get song details (GET).

server/app.ts

@@ -16,6 +16,7 @@ const invokeHandler = (handler:endpointTypes.EndpointHandler) => {
     return async (req: any, res: any) => {
         console.log("Incoming", req.method, " @ ", req.url);
         await handler(req, res)
+        .catch(endpointTypes.catchUnhandledErrors)
         .catch((_e:endpointTypes.EndpointError) => {
             let e:endpointTypes.EndpointError = _e;
             console.log("Error handling request: ", e.internalMessage);
@@ -31,9 +32,9 @@ const SetupApp = (app: any) => {
 
     // Set up REST API endpoints
     app.post(api.CreateSongEndpoint, invokeHandler(CreateSongEndpointHandler));
-    app.get(api.QuerySongsEndpoint, invokeHandler(QuerySongsEndpointHandler));
+    app.post(api.QuerySongsEndpoint, invokeHandler(QuerySongsEndpointHandler));
     app.post(api.CreateArtistEndpoint, invokeHandler(CreateArtistEndpointHandler));
-    app.get(api.QueryArtistsEndpoint, invokeHandler(QueryArtistsEndpointHandler));
+    app.post(api.QueryArtistsEndpoint, invokeHandler(QueryArtistsEndpointHandler));
     app.put(api.ModifyArtistEndpoint, invokeHandler(ModifyArtistEndpointHandler));
     app.put(api.ModifySongEndpoint, invokeHandler(ModifySongEndpointHandler));
     app.get(api.SongDetailsEndpoint, invokeHandler(SongDetailsEndpointHandler));

server/endpoints/QuerySongsEndpointHandler.ts

@@ -1,7 +1,46 @@
 const models = require('../models');
+const { Op } = require("sequelize");
 import * as api from '../../client/src/api';
 import { EndpointError, EndpointHandler, catchUnhandledErrors } from './types';
 
+const getSequelizeWhere = (queryElem: api.SongQueryElem) => {
+    var and = [];
+
+    var sequelizeOps:any = {};
+    sequelizeOps[api.SongQueryFilterOp.Eq] = Op.eq;
+    sequelizeOps[api.SongQueryFilterOp.Ne] = Op.ne;
+    sequelizeOps[api.SongQueryFilterOp.In] = Op.in;
+    sequelizeOps[api.SongQueryFilterOp.NotIn] = Op.notIn;
+    sequelizeOps[api.SongQueryElemOp.And] = Op.and;
+    sequelizeOps[api.SongQueryElemOp.Or] = Op.or;
+
+    var sequelizeProps:any = {};
+    sequelizeProps[api.SongQueryElemProperty.id] = "id";
+    sequelizeProps[api.SongQueryElemProperty.artistIds] = "artistIds";
+    sequelizeProps[api.SongQueryElemProperty.albumIds] = "albumIds";
+
+    if (queryElem.prop && queryElem.propOperator && queryElem.propOperand) {
+        const prop = sequelizeProps[queryElem.prop];
+        const op = sequelizeOps[queryElem.propOperator];
+        var filter:any = {};
+        filter[op] = queryElem.propOperand;
+        var where:any = {};
+        where[prop] = filter;
+        and.push(where);
+    }
+    if (queryElem.childrenOperator && queryElem.children) {
+        const children = queryElem.children.map((child: api.SongQueryElem) => getSequelizeWhere(child));
+        const op = sequelizeOps[queryElem.childrenOperator];
+        var where:any = {};
+        where[op] = children;
+        and.push(where)
+    }
+
+    return {
+        [Op.and]: and
+    };
+}
+
 export const QuerySongsEndpointHandler: EndpointHandler = async (req: any, res: any) => {
     if (!api.checkQuerySongsRequest(req)) {
         const e: EndpointError = {
@@ -10,7 +49,11 @@ export const QuerySongsEndpointHandler: EndpointHandler = async (req: any, res:
         };
         throw e;
     }
-    await models.Song.findAll()
+    const reqObject: api.QuerySongsRequest = req.body;
+
+    await models.Song.findAll({
+        where: getSequelizeWhere(reqObject.query)
+    })
         .then((songs: any[]) => {
             const response: api.QuerySongsResponse = {
                 ids: songs.map((song: any) => {

server/test/integration/flows/ModifyArtistFlow.js

@@ -73,8 +73,7 @@ describe('PUT /artist with an existing artist', () => {
 
             var req = chai.request(app).keepOpen();
 
-            init()
-                .then(() => createArtist(req))
+            createArtist(req)
                 .then(() => modifyArtist(req))
                 .then(() => checkArtist(req))
                 .then(() => req.close())

server/test/integration/flows/QuerySongsFlow.js

@@ -0,0 +1,73 @@
+const chai = require('chai');
+const chaiHttp = require('chai-http');
+const express = require('express');
+const models = require('../../../models');
+import { SetupApp } from '../../../app';
+import { expect } from 'chai';
+
+async function init() {
+    chai.use(chaiHttp);
+    const app = express();
+    SetupApp(app);
+    await models.sequelize.sync({ force: true });
+    return app;
+}
+
+describe('POST /song/query with no songs', () => {
+    it('should give empty list', done => {
+        init().then((app) => {
+            chai
+                .request(app)
+                .post('/song/query')
+                .send({
+                    'query': {}
+                })
+                .end((err, res) => {
+                    expect(err).to.be.null;
+                    expect(res).to.have.status(200);
+                    expect(res.body).to.deep.equal({
+                        ids: []
+                    });
+                    done();
+                });
+        });
+    });
+});
+
+describe('POST /song/query with several songs', () => {
+    it('should give empty list', done => {
+        init().then((app) => {
+            async function createSong(req) {
+                await req
+                    .post('/song')
+                    .send({
+                        title: "Song"
+                    })
+                    .then((res) => {
+                        expect(res).to.have.status(200);
+                    });
+            }
+
+            async function checkSongs(req) {
+                await req
+                    .post('/song/query')
+                    .send({ "query": {} })
+                    .then((res) => {
+                        expect(res).to.have.status(200);
+                        expect(res.body).to.deep.equal({
+                            ids: [1, 2, 3]
+                        });
+                    });
+            }
+
+            var req = chai.request(app).keepOpen();
+
+            createSong(req)
+                .then(() => createSong(req))
+                .then(() => createSong(req))
+                .then(() => checkSongs(req))
+                .then(() => req.close())
+                .then(done)
+        });
+    });
+});