ByteScout Cloud API Server – Barcode Reader API – JavaScript – Read Barcode From Uploaded File (Node.js) – Async Api

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ByteScout Cloud API Server – Barcode Reader API – JavaScript – Read Barcode From Uploaded File (Node.js) – Async Api

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ByteScout-Cloud-API-Server-JavaScript-Read-Barcode-From-Uploaded-File-(Node-js)-Async-Api.pdf

How to read barcode from uploaded file (node for barcode reader API in JavaScript with ByteScout Cloud API Server

Learn to write code read barcode from uploaded file (node for barcode reader API in JavaScript: Simple How To Tutorial

This page displays the step-by-step instructions and algorithm of how to read barcode from uploaded file (node and how to apply it in your application. ByteScout Cloud API Server was designed to assist barcode reader 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!.

The SDK samples displayed below below explain how to quickly make your application do barcode reader API in JavaScript with the help of ByteScout Cloud API Server. Open your JavaScript project and simply copy & paste the code and then run your app! You can use these JavaScript sample examples in one or many applications.

Free! Free! Free! ByteScout free trial version is available for FREE download from our website. Programming tutorials along with source code samples are assembled.

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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 file name
const SourceFile = "./sample.pdf";
// Comma-separated list of barcode types to search. 
// barcode types
const BarcodeTypes = "Code128,Code39,Interleaved2of5,EAN13";
// Comma-separated list of page indices (or ranges) to process. Leave empty for all pages. Example: '0,2-5,7-'.
const Pages = "";

// 1. RETRIEVE THE PRESIGNED URL TO UPLOAD THE FILE.
getPresignedUrl(SourceFile)
.then(([uploadUrl, uploadedFileUrl]) => {
    // 2. UPLOAD THE FILE TO CLOUD.
    uploadFile(SourceFile, uploadUrl)
    .then(() => {
        // 3. READ BARCODES FROM UPLOADED FILE
        readBarcodes(uploadedFileUrl, Pages, BarcodeTypes);
    })
    .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 readBarcodes(uploadedFileUrl, pages, barcodeTypes) {
    // Prepare request to `Barcode Reader` API endpoint
    let queryPath = `/barcode/read/from/url?types=${BarcodeTypes}&pages=${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("readBarcodes(): " + data.message);
            }
        });
    })
    .on("error", (e) => {
        // Request error
        console.log("readBarcodes(): " + 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);

                    respJsonFileArray.forEach((element) => {
                        console.log("Found barcode:");
                        console.log("  Type: " + element["TypeName"]);
                        console.log("  Value: " + element["Value"]);
                        console.log("  Document Page Index: " + element["Page"]);
                        console.log("  Rectangle: " + element["Rect"]);
                        console.log("  Confidence: " + element["Confidence"]);
                        console.log();
                    }, 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"
  }
}