deleting a material is rejected if it is referenced by a sample

src/test/helper.ts

@@ -0,0 +1,90 @@
+import supertest from 'supertest';
+import should from 'should/as-function';
+import db from "../db";
+
+
+export default class TestHelper {
+  public static auth = {
+    admin: {pass: 'Abc123!#', key: '000000000000000000001003'},
+    janedoe: {pass: 'Xyz890*)', key: '000000000000000000001002'},
+    user: {pass: 'Xyz890*)', key: '000000000000000000001001'}
+  }
+  public static res = {
+    400: {status: 'Bad request'},
+    401: {status: 'Unauthorized'},
+    403: {status: 'Forbidden'},
+    404: {status: 'Not found'},
+    500: {status: 'Internal server error'}
+  }
+
+  static before (done) {
+    process.env.port = '2999';
+    process.env.NODE_ENV = 'test';
+    db.connect('test', done);
+  }
+
+  static beforeEach (server, done) {
+    delete require.cache[require.resolve('../index')];  // prevent loading from cache
+    server = require('../index');
+    db.drop(err => {  // reset database
+      if (err) return done(err);
+      db.loadJson(require('./db.json'), done);
+    });
+    return server
+  }
+
+  static afterEach (server, done) {
+    server.close(done);
+  }
+
+  static request (server, done, options) {  // options in form: {method, url, auth: {key/basic: 'name' or 'key'/{name, pass}}, httpStatus, req, res}
+    let st = supertest(server);
+    if (options.hasOwnProperty('auth') && options.auth.hasOwnProperty('key')) {
+      options.url += '?key=' + (this.auth.hasOwnProperty(options.auth.key)? this.auth[options.auth.key].key : options.auth.key);
+    }
+    switch (options.method) {
+      case 'get':
+        st = st.get(options.url)
+        break;
+      case 'post':
+        st = st.post(options.url)
+        break;
+      case 'put':
+        st = st.put(options.url)
+        break;
+      case 'delete':
+        st = st.delete(options.url)
+        break;
+    }
+    if (options.hasOwnProperty('req')) {
+      st = st.send(options.req);
+    }
+    if (options.hasOwnProperty('auth') && options.auth.hasOwnProperty('basic')) {
+      if (this.auth.hasOwnProperty(options.auth.basic)) {
+        st = st.auth(options.auth.basic, this.auth[options.auth.basic].pass)
+      }
+      else {
+        st = st.auth(options.auth.basic.name, options.auth.basic.pass)
+      }
+    }
+    st = st.expect('Content-type', /json/)
+      .expect(options.httpStatus);
+    if (options.hasOwnProperty('res')) {
+      return st.end((err, res) => {
+        if (err) return done (err);
+        should(res.body).be.eql(options.res);
+        done();
+      });
+    }
+    else if (this.res.hasOwnProperty(options.httpStatus) && options.default !== false) {
+      return st.end((err, res) => {
+        if (err) return done (err);
+        should(res.body).be.eql(this.res[options.httpStatus]);
+        done();
+      });
+    }
+    else {
+      return st;
+    }
+  }
+}

src/test/loadDev.ts

@@ -0,0 +1,12 @@
+import db from '../db';
+
+db.connect('dev', () => {
+  console.info('dropping data...');
+  db.drop(() => {  // reset database
+    console.info('loading data...');
+    db.loadJson(require('./db.json'), () => {
+      console.info('done');
+      process.exit(0);
+    });
+  });
+});