JavaScript HTTP Client Class

Simple class to perform HTTP Request in plain JavaScript.

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Edited: 2022-09-27 12:31

The HTTP client can be used to perform AJAX requests and update the page-content dynamically using GET and POST requests.

The class can be used like this:

httpClient = new http_client();

httpClient.get("/api/request-headers", function (response) {
  document.getElementById("_id_of_element").innerText = response;
});

When used on Beamtic, there is no need to instantiate the class, since it is loaded by the system automatically. Instead, authors may use it directly:

httpClient.get("/api/time/date", function (response) {
  document.getElementById("_id_of_element").innerText = response;
});

To use the HTTP client in articles here on Beamtic, you need only make use of HTML script elements in the article's code.

JavaScript HTTP Client

class http_client {
    post(URL = 'required', postData = false, callBack = false) {
    var http = new XMLHttpRequest();
    http.open('POST', URL, true);
    http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    
    if ('string' == typeof postData) {
      http.send(postData);
    } else {
      if ('function' == typeof postData && false == callBack) {
        callBack = postData;
      }
      http.send();
    }
    this.ready(http, callBack);
  };
  get(URL = 'required', callBack = false) {
    var http = new XMLHttpRequest();
    http.open('GET', URL, true);
    http.send();
    this.ready(http, callBack);
  };
  ready(http, callBack) {
    http.onreadystatechange = () => {
      if (http.readyState == 4) { // && this.xmlhttp.status == 200
        if (callBack !== false) {
          // The callBack function contains
          // the actions to perform after loading the response.

          // It is passed to the get()
          // method from the calling block
          callBack(http.responseText);
        } else {
          return true; // If not returning the response,
                       // return true
        }
      }
    };
  };
}

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