rewrite unit tests

test/music_url.test.js

@@ -0,0 +1,23 @@
+const assert = require('assert')
+const request = require('request')
+host = global.host || 'http://localhost:3000'
+
+describe("测试获取歌曲是否正常", () => {
+  it("歌曲的 url 不应该为空", done => {
+    const qs = {
+      id: 462791935,
+      br: 999000
+    }
+
+    request.get({url: `${host}/music/url`,qs: qs}, (err, res, body) => {
+      if (!err && res.statusCode == 200) {
+        body = JSON.parse(body)
+        assert(!!body.data[0].url)
+        done()
+      }
+      else{
+        done(err)
+      }
+    })
+  });
+});