ByteScout Cloud API Server – PDF Optimization API – JavaScript – Optimize PDF From Uploaded File (Node.js) – Async API

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ByteScout Cloud API Server – PDF Optimization API – JavaScript – Optimize PDF From Uploaded File (Node.js) – Async API

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

How to optimize PDF from uploaded file (node for PDF optimization API in JavaScript with ByteScout Cloud API Server

Learn to write code optimize PDF from uploaded file (node for PDF optimization API in JavaScript: Simple How To Tutorial

On this page, you will find sample source codes which show you how to handle a complex task, such as, PDF optimization API in JavaScript. ByteScout Cloud API Server was designed to assist PDF optimization API in JavaScript. ByteScout Cloud API Server is API server that is ready to use and can be installed and deployed in less than 30 minutes on your own Windows server or server in a cloud. It can save data and files on your local server-based file storage or in Amazon AWS S3 storage. Data is processed solely on the API server and is powered by ByteScout engine, no cloud services or Internet connection is required for data processing..

JavaScript code snippet like this for ByteScout Cloud API Server works best when you need to quickly implement PDF optimization API in your JavaScript application. For implementation of this functionality, please copy and paste the code below into your app using code editor. Then compile and run your app. Writing JavaScript application mostly includes various stages of the software development so even if the functionality works please check it with your data and the production environment.

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";
// PDF document password. Leave empty for unprotected documents.
const Password = "";
// Destination PDF file name
const DestinationFile = "./result.pdf";

// 1. RETRIEVE PRESIGNED URL TO UPLOAD FILE.
getPresignedUrl(SourceFile)
.then(([uploadUrl, uploadedFileUrl]) => {
    // 2. UPLOAD THE FILE TO CLOUD.
    uploadFile(SourceFile, uploadUrl)
    .then(() => {
        // 3. OPTIMIZE UPLOADED PDF FILE
        optimizePdf(uploadedFileUrl, Password, DestinationFile);
    })
    .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 optimizePdf(uploadedFileUrl, password, destinationFile) {
    // Prepare request to `Optimize PDF` API endpoint
    var queryPath = `/pdf/optimize?name=${path.basename(destinationFile)}&password=${password}&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);
            console.log(`Job #${data.jobId} has been created!`);

            if (data.error == false) {
                checkIfJobIsCompleted(data.jobId, data.url, destinationFile);
            }
            else {
                // Service reported error
                console.log("readBarcodes(): " + data.message);
            }
        });
    })
    .on("error", (e) => {
        // Request error
        console.log("readBarcodes(): " + e);
    });
}

function checkIfJobIsCompleted(jobId, resultFileUrl, destinationFile) {
    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, resultFileUrl, destinationFile);}, 3000);
            }
            else if (data.status == "success") {
                // Download PDF file
                var file = fs.createWriteStream(destinationFile);
                https.get(resultFileUrl, (response2) => {
                    response2.pipe(file)
                        .on("close", () => {
                            console.log(`Generated PDF file saved as "${destinationFile}" file.`);
                        });
                });
            }
            else {
                console.log(`Operation ended with status: "${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"
  }
}