ByteScout Cloud API Server – PDF To Image API – JavaScript – Convert PDF To JPEG From Uploaded File (Node.js) – Async API

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ByteScout Cloud API Server – PDF To Image API – JavaScript – Convert PDF To JPEG From Uploaded File (Node.js) – Async API

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ByteScout-Cloud-API-Server-JavaScript-Convert-PDF-To-JPEG-From-Uploaded-File-(Node-js)-Async-API.pdf

How to convert PDF to JPEG from uploaded file (node for PDF to image API in JavaScript using ByteScout Cloud API Server

How to convert PDF to JPEG from uploaded file (node for PDF to image API in JavaScript: Step By Step Instructions

If you want a quick and easy way to add a required functionality into your application then check this sample source code documentation. ByteScout Cloud API Server was designed to assist PDF to image API in JavaScript. ByteScout Cloud API Server is the ready to use Web API Server that can be deployed in less than 30 minutes into your own in-house server or into private cloud server. Can store data on in-house local server based storage or in Amazon AWS S3 bucket. Processing data solely on the server using buil-in ByteScout powered engine, no cloud services are used to process your data!.

If you want to speed up the application’s code writing then JavaScript code samples for JavaScript developers help to implement using ByteScout Cloud API Server. For implementation of this functionality, please copy and paste the code below into your app using code editor. Then compile and run your app. Use of ByteScout Cloud API Server in JavaScript is also described in the documentation given along with the product.

Trial version of ByteScout is available for free download from our website. This and other source code samples for JavaScript and other programming languages are available.

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app.js

      /*jshint esversion: 6 */

// Please NOTE: In this sample we're assuming Cloud Api Server is hosted at "https://localhost". 
// If it's not then please replace this with with your hosting url.

var https = require("https");
var path = require("path");
var fs = require("fs");

// `request` module is required for file upload.
// Use "npm install request" command to install.
var request = require("request");

// Source PDF file
const SourceFile = "./sample.pdf";
// Comma-separated list of page indices (or ranges) to process. Leave empty for all pages. Example: '0,2-5,7-'.
const Pages = "";
// PDF document password. Leave empty for unprotected documents.
const Password = "";

// 1. RETRIEVE PRESIGNED URL TO UPLOAD FILE.
getPresignedUrl(SourceFile)
    .then(([uploadUrl, uploadedFileUrl]) => {
        // 2. UPLOAD THE FILE TO CLOUD.
        uploadFile(SourceFile, uploadUrl)
            .then(() => {
                // 3. CONVERT UPLOADED PDF FILE TO JPEG
                convertPdfToJpeg(uploadedFileUrl, Password, Pages);
            })
            .catch(e => {
                console.log(e);
            });
    })
    .catch(e => {
        console.log(e);
    });


function getPresignedUrl(localFile) {
    return new Promise(resolve => {
        // Prepare request to `Get Presigned URL` API endpoint
        let queryPath = `/file/upload/get-presigned-url?contenttype=application/octet-stream&name=${path.basename(SourceFile)}`;
        let reqOptions = {
            host: "localhost",
            path: encodeURI(queryPath)
        };
        // Send request
        https.get(reqOptions, (response) => {
            response.on("data", (d) => {
                let data = JSON.parse(d);
                if (data.error == false) {
                    // Return presigned url we received
                    resolve([data.presignedUrl, data.url]);
                }
                else {
                    // Service reported error
                    console.log("getPresignedUrl(): " + data.message);
                }
            });
        })
            .on("error", (e) => {
                // Request error
                console.log("getPresignedUrl(): " + e);
            });
    });
}

function uploadFile(localFile, uploadUrl) {
    return new Promise(resolve => {
        fs.readFile(SourceFile, (err, data) => {
            request({
                method: "PUT",
                url: uploadUrl,
                body: data,
                headers: {
                    "Content-Type": "application/octet-stream"
                }
            }, (err, res, body) => {
                if (!err) {
                    resolve();
                }
                else {
                    console.log("uploadFile() request error: " + e);
                }
            });
        });
    });
}

function convertPdfToJpeg(uploadedFileUrl, password, pages) {
    // Prepare URL for `PDF To JPEG` API call
    var queryPath = `/pdf/convert/to/jpg?password=${password}&pages=${pages}&url=${uploadedFileUrl}&async=True`;
    let reqOptions = {
        host: "localhost",
        path: encodeURI(queryPath),
        method: "GET" 
    };
    // Send request
    https.get(reqOptions, (response) => {
        response.on("data", (d) => {
            response.setEncoding("utf8");
            // Parse JSON response
            let data = JSON.parse(d);
            if (data.error == false) {
                console.log(`Job #${data.jobId} has been created!`);
                checkIfJobIsCompleted(data.jobId, data.url);
            }
            else {
                // Service reported error
                console.log("convertPdfToJpeg(): " + data.message);
            }
        });
    })
        .on("error", (e) => {
            // Request error
            console.log("convertPdfToJpeg(): " + e);
        });
}

function checkIfJobIsCompleted(jobId, resultFileUrlJson) {

    let queryPath = `/job/check?jobid=${jobId}`;
    let reqOptions = {
        host: "localhost",
        path: encodeURI(queryPath),
        method: "GET" 
    };

    https.get(reqOptions, (response) => {
        response.on("data", (d) => {
            response.setEncoding("utf8");

            // Parse JSON response
            let data = JSON.parse(d);
            console.log(`Checking Job #${jobId}, Status: ${data.status}, Time: ${new Date().toLocaleString()}`);

            if (data.status == "working") {
                // Check again after 3 seconds
                setTimeout(function(){checkIfJobIsCompleted(jobId, resultFileUrlJson)} , 3000);
            }
            else if (data.status == "success") {

                request({ method: 'GET', uri: resultFileUrlJson, gzip: true },
                    function (error, response, body) {

                        // Parse JSON response
                        let respJsonFileArray = JSON.parse(body);
                        let page = 1;

                        respJsonFileArray.forEach((url) => {
                            var localFileName = `./page${page}.jpg`;
                            var file = fs.createWriteStream(localFileName);
                            https.get(url, (response2) => {
                                response2.pipe(file)
                                    .on("close", () => {
                                        console.log(`Generated JPEG file saved as "${localFileName} file."`);
                                    });
                            });
                            page++;
                        }, this);

                    });
            }
            else {
                console.log(`Operation ended with status: "${data.status}".`);
            }
        })
    });
}

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package.json

      {
  "name": "test",
  "version": "1.0.0",
  "description": "PDF.co",
  "main": "app.js",
  "scripts": {
  },
  "keywords": [
    "pdf.co",
    "web",
    "api",
    "bytescout",
    "api"
  ],
  "author": "ByteScout & PDF.co",
  "license": "ISC",
  "dependencies": {
    "request": "^2.88.2"
  }
}