freeCodeCamp/curriculum/challenges/english/05-back-end-development-and-apis/basic-node-and-express/get-query-parameter-input-from-the-client.md

id	title	challengeType	forumTopicId	dashedName
587d7fb2367417b2b2512bf6	Get Query Parameter Input from the Client	2	301512	get-query-parameter-input-from-the-client

--description--

Another common way to get input from the client is by encoding the data after the route path, using a query string. The query string is delimited by a question mark (?), and includes field=value couples. Each couple is separated by an ampersand (&). Express can parse the data from the query string, and populate the object req.query. Some characters, like the percent (%), cannot be in URLs and have to be encoded in a different format before you can send them. If you use the API from JavaScript, you can use specific methods to encode/decode these characters.

route_path: '/library'
actual_request_URL: '/library?userId=546&bookId=6754'
req.query: {userId: '546', bookId: '6754'}

--instructions--

Build an API endpoint, mounted at GET /name. Respond with a JSON document, taking the structure { name: 'firstname lastname'}. The first and last name parameters should be encoded in a query string e.g. ?first=firstname&last=lastname.

Note: In the following exercise you are going to receive data from a POST request, at the same /name route path. If you want, you can use the method app.route(path).get(handler).post(handler). This syntax allows you to chain different verb handlers on the same path route. You can save a bit of typing, and have cleaner code.

--hints--

Test 1 : Your API endpoint should respond with the correct name

(getUserInput) =>
  $.get(getUserInput('url') + '/name?first=Mick&last=Jagger').then(
    (data) => {
      assert.equal(
        data.name,
        'Mick Jagger',
        'Test 1: "GET /name" route does not behave as expected'
      );
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );

Test 2 : Your API endpoint should respond with the correct name

(getUserInput) =>
  $.get(getUserInput('url') + '/name?last=Richards&first=Keith').then(
    (data) => {
      assert.equal(
        data.name,
        'Keith Richards',
        'Test 2: "GET /name" route does not behave as expected'
      );
    },
    (xhr) => {
      throw new Error(xhr.responseText);
    }
  );

--solutions--

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