Merge - NodeJS

//Simple script to showcasing how to use the Merge API in the LEADTOOLS Cloud Services. 
 
const axios = require("axios"); 
 
//If uploading a file as multi-part content, we will need the file-system library installed. 
//const fs = require('fs'); 
 
const FormatsEnum = { 
  png: 1, 
  jpeg: 2, 
  tiff: 3, 
  pdf: 4, 
  pdfa: 5, 
  pdfImage: 6, 
  pdfImageOverText: 7, 
  pdfaImageOverText: 8, 
  docx: 9, 
  docxFramed: 10, 
  rtf: 11, 
  rtfFramed: 12, 
  txt: 13, 
  txtFramed: 14, 
}; 
 
const servicesUrl = "https://azure.leadtools.com/api/"; 
 
const tiffUrl = "http://demo.leadtools.com/images/cloud_samples/ocr1-4.tif"; 
const pdfUrl = "https://demo.leadtools.com/images/pdf/leadtools.pdf"; 
 
let firstFileId = ""; 
let secondFileId = ""; 
const outputFormat = FormatsEnum.pdf; 

uploadFile(tiffUrl, firstFileUploadCallback); 
 
function uploadFile(url, callback) { 
  const uploadUrl = `${servicesUrl}uploadFile?forMerge=true&fileurl=${url}`; 
  axios 
    .post(uploadUrl, {}, getRequestOptions(uploadUrl)) 
    .then((res) => { 
      callback(res.error, res, res.data); 
    }) 
    .catch((err) => { 
      console.error(err); 
    }); 
 
  //If uploading a file as multi-part content: 
  /*var uploadUrl = servicesUrl + "uploadFile?forMerge=true"; 
    const form = new FormData(); 
    form.append("file", fs.createReadStream('path\to\inputFile')); 
    axios.post(uploadUrl, form, getRequestOptions(uploadUrl)).then((res) => { 
        callback(res.error, res, res.data); 
    }).catch ((err) => { 
        console.error(err); 
    });*/ 
} 
 
function firstFileUploadCallback(error, response, body) { 
  if (!error && response.status === 200) { 
    firstFileId = body; 
    console.log("First File ID: " + firstFileId); 
 
    checkVerification(firstFileId, uploadSecondFile); 
  } 
} 
 
function uploadSecondFile() { 
  uploadFile(pdfUrl, secondFileUploadCallback); 
} 
 
function secondFileUploadCallback(error, response, body) { 
  if (!error && response.status === 200) { 
    secondFileId = body; 
    console.log("Second File ID: " + secondFileId); 
 
    checkVerification(secondFileId, mergeFile); 
  } 
} 

async function checkVerification(id, callback) { 
  const queryUrl = servicesUrl + "Query?id=" + id; 
  await axios 
    .post(queryUrl, {}, getRequestOptions(queryUrl)) 
    .then((res) => { 
      const results = res.data; 
      if (!res.error && results["FileStatus"] !== 123) { 
        console.log("Verification finished with return code: " + res.status); 
        if (results["FileStatus"] == 122) { 
          callback(); 
        } else { 
          console.log( 
            "File failed verification with File Status: " + 
              results["FileStatus"] 
          ); 
        } 
      } else { 
        //The file has not yet finished processing. 
        return new Promise((resolve) => { 
          setTimeout(() => { 
            //Sleep for 5 seconds before trying again 
            resolve(checkVerification(id, callback)); //Call the method again. 
          }, 5000); 
        }); 
      } 
    }) 
    .catch((err) => { 
      console.error(err); 
    }); 
} 

function mergeFile() { 
  const mergeUrl = `${servicesUrl}Conversion/Merge?format=${outputFormat}`; 
  const options = getRequestOptions(mergeUrl); 
  const json = JSON.stringify([ 
    { 
      firstPage: 1, 
      lastPage: -1, 
      fileId: firstFileId, 
    }, 
    { 
      pages: [5, 1, 2, 4, 3], 
      fileId: secondFileId, 
    }, 
  ]); 
  axios.post(mergeUrl, json, options).then((res) => { 
    console.log("Merging Files..."); 
    if (!res.error && res.status === 200) { 
      console.log("Merge command was successful"); 
      queryServices(firstFileId); 
    } else { 
      console.log("Merge failed with HTTP code: " + res.status); 
      console.log(res.data); 
    } 
  }); 
} 

async function queryServices(guid) { 
  //Function to query the status of a request.  If the request has not yet finished, this function will recursively call itself until the file has finished. 
  const queryUrl = servicesUrl + "Query?id=" + guid; 
  await axios 
    .post(queryUrl, {}, getRequestOptions(queryUrl)) 
    .then((res) => { 
      const results = res.data; 
      if ( 
        !res.error && 
        results["FileStatus"] !== 100 && 
        results["FileStatus"] !== 123 
      ) { 
        console.log("File finished processing with return code: " + res.status); 
        console.log(results["FileStatus"]); 
        if (results["FileStatus"] !== 200) { 
          return; 
        } 
        console.log("Results: \n"); 
        parseJson(results["RequestData"]); 
      } else { 
        //The file has not yet finished processing. 
        return new Promise((resolve) => { 
          setTimeout(() => { 
            //Sleep for 5 seconds before trying again 
            resolve(queryServices(guid)); //Call the method again. 
          }, 5000); 
        }); 
      } 
    }) 
    .catch((err) => { 
      console.error(err); 
    }); 
} 

function parseJson(jsonObject) { 
  //Function to decode the JSON object that was returned by the LEADTOOLS CloudServices. 
  for (let i = 0; i < jsonObject.length; i++) { 
    let currentRequest = jsonObject[i]; 
    console.log("Service Type: " + currentRequest["ServiceType"]); 
    if (currentRequest["ServiceType"] === "Conversion") { 
      console.log("Urls: "); 
      currentRequest["urls"].forEach((url) => { 
        console.log(url); 
      }); 
    } 
  } 
} 

function getRequestOptions(url) { 
  const appId = "Replace with Application ID"; 
  const password = "Replace with Application Password"; 
 
  const token = Buffer.from(`${appId}:${password}`, "utf8").toString("base64"); 
  //Function to generate and return HTTP request  options. 
  const requestOptions = { 
    url: url, 
    data: {}, 
    //If uploading a file as multi-part content, remove the Content-Length header. 
    headers: { 
      "Content-Length": 0, 
      Authorization: `Basic ${token}`, 
    }, 
  }; 
  return requestOptions; 
}