// Fetch the original image fetch('./tortoise.png') // Retrieve its body as ReadableStream .then((response) => { const reader = response.body.getReader(); // }); Reading the stream Now you've got your reader attached, you can read data chunks out of the stream using the ReadableStreamDefaultReader.read () method. This will also help us answer your question better. According to MDN, Fetch is described as below: The Fetch API provides a JavaScript interface for accessing and manipulating parts of the HTTP pipeline, such as requests and responses. Please note: .then call is attached directly to fetch, so that when we have the response, it doesnt wait for other fetches, but starts to read .json() immediately. 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The API responds with an image file on request. This seemingly small detail has had a huge impact on the performance and behavior of sites, so in this article, we'll explain the concept and look at technologies that make it possible: in particular, the Fetch API. Help to translate the content of this tutorial to your language! We won't go through an example that uses XMLHttpRequest, but we will show you what the XMLHttpRequest version of our first can store request would look like: We also have to wrap the whole thing in the trycatch block, to handle any errors thrown by open() or send(). A new tech publication by Start it up (https://medium.com/swlh). Always undefined when done is true. options: It is used to specify other options which you can read more about here. When the fetch is successful, we read a Blob out of the response using blob (), put it into an object URL using URL.createObjectURL, and then set that URL as the source of an <img> element to display the image. I can access and see image file on http://192.168.22.124:3000/source/592018124023PM-pexels-photo.jpg. So I can access it somewhere. You can find this example live on GitHub, and see the source code. Apparently stackoverflow fellows didn't like my question, I think they didn't understand the problem :(. There are however a lot of different subjects discussed in this article, which has only really scratched the surface. Calculating probabilities from d6 dice pool (Degenesis rules for botches and triggers). Syntax: How To Read and Process Files with the JavaScript FileReader API By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. In this post, we will learn how to fetch data from 3rd party API and show the result on the HTML page. This is achieved via the ReadableStream.tee() method it outputs an array containing two identical copies of the original readable stream, which can then be read independently by two separate readers. For this example, we'll request data out of a few different text files and use them to populate a content area. A web page consists of an HTML page and (usually) various other files, such as stylesheets, scripts, and images. When I click on localhost:3001/613348fe-52e4-4baa-8e76-e48332494e19 I get redirected to my sign up page. Requests shouldnt wait for each other. Check out this classic DEV post on the subject. Norm of an integral operator involving linear and exponential terms. The main API here is the Fetch API. If the stream becomes errored, the promise will be rejected with the relevant error. Once the download is complete the onload callback will be triggered and the destination's source will be that of the newly downloaded image. Abnormal HTTP-statuses, such as 404 or 500 do not cause an error. readAsText (file, format): Reads the file as USVString (almost like a string), and you can specify an optional . If you don't know what that is, read the module on asynchronous JavaScript, and in particular the article on promises, then come back here. In some cases, we may want to read files (.csv,.txt.) Start Fetching LocalData! Create an async function getUsers(names), that gets an array of GitHub logins, fetches the users from GitHub and returns an array of GitHub users. As far as I know, that code is fetching a file with relative path to where the code is located. network problems, or theres no such site. This series of files will act as our fake database; in a real application, we'd be more likely to use a server-side language like PHP, Python, or Node to request our data from a database. This predated Fetch, and was really the first API widely used to implement AJAX. fetch ("URL") .then (res => res.blob ()) .then (data => { var a = document.createElement ("a"); a.href = window.URL.createObjectURL (data); a.download = "FILENAME"; a.click (); }); With you every step of your journey. Finally, we call readAsDataURL with imageBlob to read it into a base64 string. Just inside the