PDF to PDF API - Node.js

Join multiple PDF files in Node.js using the Pdfcrowd API v2. The API is easy to use and the integration takes only a couple of lines of code.

Installation

Install the client library from npm
npm install pdfcrowd

Learn more about other install options.

Authentication

Authentication is needed in order to use the Pdfcrowd API. The credentials used for accessing the API are your Pdfcrowd username and the API key.
Sign up for a Free Trial

Examples

var pdfcrowd = require("pdfcrowd");

// create the API client instance
var client = new pdfcrowd.PdfToPdfClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

// configure the conversion
try {
    client.addPdfFile("/path/to/cover.pdf");
    client.addPdfFile("/path/to/proposal.pdf");
    client.addPdfFile("/path/to/price.pdf");
    client.addPdfFile("/path/to/contact.pdf");
} catch(why) {
    console.error("Pdfcrowd Error: " + why);
    console.error("Pdfcrowd Error Code: " + why.getCode());
    console.error("Pdfcrowd Error Message: " + why.getMessage());
    process.exit(1);
}

// run the conversion and write the result to a file
client.convertToFile(
    "offer.pdf",
    function(err, fileName) {
        if (err) return console.error("Pdfcrowd Error: " + err);
        console.log("Success: the file was created " + fileName);
    });
var pdfcrowd = require("pdfcrowd");

// create the API client instance
var client = new pdfcrowd.PdfToPdfClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

// configure the conversion
try {
    client.addPdfFile("/path/to/cover.pdf");
    client.addPdfFile("/path/to/proposal.pdf");
    client.addPdfFile("/path/to/price.pdf");
    client.addPdfFile("/path/to/contact.pdf");
} catch(why) {
    console.error("Pdfcrowd Error: " + why);
    console.error("Pdfcrowd Error Code: " + why.getCode());
    console.error("Pdfcrowd Error Message: " + why.getMessage());
    process.exit(1);
}

// use predefined callback for saving to a file
var callbacks = pdfcrowd.saveToFile("offer.pdf");

// set custom error callback
callbacks.error = function(errMessage, statusCode) {
    if(statusCode) {
        console.error("Pdfcrowd Error: " + statusCode + " - " + errMessage);
    } else {
        console.error("Pdfcrowd Error: " + errMessage);
    }
};

// run the conversion and write the result to a file
client.convert(callbacks);
var pdfcrowd = require("pdfcrowd");
var fs = require("fs");

// create the API client instance
var client = new pdfcrowd.PdfToPdfClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

// configure the conversion
try {
    client.addPdfRawData(fs.readFileSync("/path/to/cover.pdf"));
    client.addPdfRawData(fs.readFileSync("/path/to/proposal.pdf"));
    client.addPdfRawData(fs.readFileSync("/path/to/price.pdf"));
    client.addPdfRawData(fs.readFileSync("/path/to/contact.pdf"));
} catch(why) {
    console.error("Pdfcrowd Error: " + why);
    console.error("Pdfcrowd Error Code: " + why.getCode());
    console.error("Pdfcrowd Error Message: " + why.getMessage());
    process.exit(1);
}

// run the conversion and write the result to a file
client.convertToFile(
    "offer.pdf",
    function(err, fileName) {
        if (err) return console.error("Pdfcrowd Error: " + err);
        console.log("Success: the file was created " + fileName);
    });
var pdfcrowd = require("pdfcrowd");
var fs = require("fs");

// create the API client instance
var client = new pdfcrowd.PdfToPdfClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

// configure the conversion
try {
    client.addPdfRawData(fs.readFileSync("/path/to/cover.pdf"));
    client.addPdfFile("/path/to/proposal.pdf");
    client.addPdfRawData(fs.readFileSync("/path/to/price.pdf"));
    client.addPdfFile("/path/to/contact.pdf");
} catch(why) {
    console.error("Pdfcrowd Error: " + why);
    console.error("Pdfcrowd Error Code: " + why.getCode());
    console.error("Pdfcrowd Error Message: " + why.getMessage());
    process.exit(1);
}

// run the conversion and write the result to a file
client.convertToFile(
    "offer.pdf",
    function(err, fileName) {
        if (err) return console.error("Pdfcrowd Error: " + err);
        console.log("Success: the file was created " + fileName);
    });
var pdfcrowd = require("pdfcrowd");

// create the API client instance
var client = new pdfcrowd.PdfToPdfClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

// configure the conversion
try {
    client.addPdfFile("/path/to/proposal.pdf");
    client.setPageWatermark("/path/to/watermark.pdf");
} catch(why) {
    console.error("Pdfcrowd Error: " + why);
    console.error("Pdfcrowd Error Code: " + why.getCode());
    console.error("Pdfcrowd Error Message: " + why.getMessage());
    process.exit(1);
}

// run the conversion and write the result to a file
client.convertToFile(
    "company_offer.pdf",
    function(err, fileName) {
        if (err) return console.error("Pdfcrowd Error: " + err);
        console.log("Success: the file was created " + fileName);
    });
var pdfcrowd = require("pdfcrowd");

// create the API client instance
var client = new pdfcrowd.PdfToPdfClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

// configure the conversion
try {
    client.addPdfFile("/path/to/not_linearized.pdf");
    client.setLinearize(true);
} catch(why) {
    console.error("Pdfcrowd Error: " + why);
    console.error("Pdfcrowd Error Code: " + why.getCode());
    console.error("Pdfcrowd Error Message: " + why.getMessage());
    process.exit(1);
}

// run the conversion and write the result to a file
client.convertToFile(
    "linearized.pdf",
    function(err, fileName) {
        if (err) return console.error("Pdfcrowd Error: " + err);
        console.log("Success: the file was created " + fileName);
    });
var pdfcrowd = require("pdfcrowd");
var fs = require("fs");

// create the API client instance
var client = new pdfcrowd.PdfToPdfClient("demo", "ce544b6ea52a5621fb9d55f8b542d14d");

// configure the conversion
try {
    client.setDebugLog(true);
    client.addPdfRawData(fs.readFileSync("/path/to/cover.pdf"));
    client.addPdfRawData(fs.readFileSync("/path/to/proposal.pdf"));
} catch(why) {
    console.error("Pdfcrowd Error: " + why);
    console.error("Pdfcrowd Error Code: " + why.getCode());
    console.error("Pdfcrowd Error Message: " + why.getMessage());
    process.exit(1);
}

// run the conversion and write the result to a file
client.convertToFile(
    "offer.pdf",
    function(err, fileName) {
        if (err) return console.error("Pdfcrowd Error: " + err);
        console.log("Success: the file was created " + fileName);
        
        // print URL to the debug log
        console.log("Debug log url: " + client.getDebugLogUrl());
        
        // print the number of available conversion credits in your account
        console.log("Remaining credit count: " + client.getRemainingCreditCount());
        
        // print the number of credits consumed by the conversion
        console.log("Consumed credit count: " + client.getConsumedCreditCount());
        
        // print the unique ID of the conversion
        console.log("Job id: " + client.getJobId());
        
        // print the total number of pages in the output document
        console.log("Page count: " + client.getPageCount());
        
        // print the size of the output in bytes
        console.log("Output size: " + client.getOutputSize());
    });

Tips & Tricks

Error Handling

try {
    // call the API 
}
catch(why) {
    // print error
    console.error("Pdfcrowd Error: " + why);

    // print just error code
    console.error("Pdfcrowd Error Code: " + why.getCode());

    // print just error message
    console.error("Pdfcrowd Error Message: " + why.getMessage());

    // or handle the error in your way
}

Troubleshooting

API Reference - class PdfToPdfClient

Conversion from PDF to PDF. All setter methods return PdfToPdfClient object unless otherwise specified.

Constructor

function PdfToPdfClient(userName, apiKey)
Constructor for the Pdfcrowd API client.
Parameter Description Default
userName
Your username at Pdfcrowd.
apiKey
Your API key.

 

PDF Manipulation

function setAction(action)
Specifies the action to be performed on the input PDFs.
Parameter Description Default
action
Allowed values:
  • join
    Concatenate input PDFs into a single one.
  • shuffle
    Collate pages from input PDFs into a single one, take one page at a time from each input PDF. This is useful when combining two scanned documents containing odd and even pages.
join
function convert(callbacks)
Perform an action on the input files.
Parameter Description Default
callbacks
The object that defines the following functions:
  • data(readStream) - called when the output data can be read from readStream
  • error(message, statusCode) - called when an error occurs
  • end() - called when the conversion finishes
The client library provides 2 helper functions that can be used here:
  • saveToFile(filePath[, callback]) - saves the output data to a file
    • filePath - the output file path
    • callback(err, filePath) - called when the conversion finishes
  • sendPdfInHttpResponse(response[, fileName, disposition]) - sends the generated PDF in an HTTP response
    • response - the response object
    • fileName - the desired file name
    • disposition - the response content disposition, can be "attachment" or "inline", the default is "attachment".
function convertToFile(filePath, callback)
Perform an action on the input files and write the output PDF to a file.
Parameter Description Default
filePath
The output file path.
The string must not be empty.
callback
The callback(error, filePath) function is called when the conversion finishes. The error object is present if an error occurred, filePath is the output file path.
function addPdfFile(filePath)
Add a PDF file to the list of the input PDFs.
Parameter Description Default
filePath
The file path to a local PDF file.
The file must exist and not be empty.
function addPdfRawData(pdfRawData)
Add in-memory raw PDF data to the list of the input PDFs.
Typical usage is for adding PDF created by another Pdfcrowd converter.

Example in PHP:
$clientPdf2Pdf->addPdfRawData($clientHtml2Pdf->convertUrl('http://www.example.com'));
Parameter Description Default
pdfRawData
The raw PDF data.
The input data must be PDF content.

 

Watermark & Background

function setPageWatermark(pageWatermark)
Apply the first page of the watermark PDF to every page of the output PDF.
Parameter Description Default
pageWatermark
The file path to a local watermark PDF file.
The file must exist and not be empty.
function setMultipageWatermark(multipageWatermark)
Apply each page of the specified watermark PDF to the corresponding page of the output PDF.
Parameter Description Default
multipageWatermark
The file path to a local watermark PDF file.
The file must exist and not be empty.
function setPageBackground(pageBackground)
Apply the first page of the specified PDF to the background of every page of the output PDF.
Parameter Description Default
pageBackground
The file path to a local background PDF file.
The file must exist and not be empty.
function setMultipageBackground(multipageBackground)
Apply each page of the specified PDF to the background of the corresponding page of the output PDF.
Parameter Description Default
multipageBackground
The file path to a local background PDF file.
The file must exist and not be empty.

 

PDF Format

Miscellaneous values for PDF output.

function setLinearize(linearize)
Create linearized PDF. This is also known as Fast Web View.
Parameter Description Default
linearize
Set to true to create linearized PDF.
false
function setEncrypt(encrypt)
Encrypt the PDF. This prevents search engines from indexing the contents.
Parameter Description Default
encrypt
Set to true to enable PDF encryption.
false
function setUserPassword(userPassword)
Protect the PDF with a user password. When a PDF has a user password, it must be supplied in order to view the document and to perform operations allowed by the access permissions.
Parameter Description Default
userPassword
The user password.
function setOwnerPassword(ownerPassword)
Protect the PDF with an owner password. Supplying an owner password grants unlimited access to the PDF including changing the passwords and access permissions.
Parameter Description Default
ownerPassword
The owner password.
function setNoPrint(noPrint)
Disallow printing of the output PDF.
Parameter Description Default
noPrint
Set to true to set the no-print flag in the output PDF.
false
function setNoModify(noModify)
Disallow modification of the ouput PDF.
Parameter Description Default
noModify
Set to true to set the read-only only flag in the output PDF.
false
function setNoCopy(noCopy)
Disallow text and graphics extraction from the output PDF.
Parameter Description Default
noCopy
Set to true to set the no-copy flag in the output PDF.
false

 

Viewer Preferences

These preferences specify how a PDF viewer should present the document. The preferences may be ignored by some PDF viewers.

function setPageLayout(pageLayout)
Specify the page layout to be used when the document is opened.
Parameter Description Default
pageLayout
Allowed values:
  • single-page
    Display one page at a time.
  • one-column
    Display the pages in one column.
  • two-column-left
    Display the pages in two columns, with odd-numbered pages on the left.
  • two-column-right
    Display the pages in two columns, with odd-numbered pages on the right.
function setPageMode(pageMode)
Specify how the document should be displayed when opened.
Parameter Description Default
pageMode
Allowed values:
  • full-screen
    Full-screen mode.
  • thumbnails
    Thumbnail images are visible.
  • outlines
    Document outline is visible.
function setInitialZoomType(initialZoomType)
Specify how the page should be displayed when opened.
Parameter Description Default
initialZoomType
Allowed values:
  • fit-width
    The page content is magnified just enough to fit the entire width of the page within the window.
  • fit-height
    The page content is magnified just enough to fit the entire height of the page within the window.
  • fit-page
    The page content is magnified just enough to fit the entire page within the window both horizontally and vertically. If the required horizontal and vertical magnification factors are different, use the smaller of the two, centering the page within the window in the other dimension.
function setInitialPage(initialPage)
Display the specified page when the document is opened.
Parameter Description Default
initialPage
Must be a positive integer number.
function setInitialZoom(initialZoom)
Specify the initial page zoom in percents when the document is opened.
Parameter Description Default
initialZoom
Must be a positive integer number.
function setHideToolbar(hideToolbar)
Specify whether to hide the viewer application's tool bars when the document is active.
Parameter Description Default
hideToolbar
Set to true to hide tool bars.
false
function setHideMenubar(hideMenubar)
Specify whether to hide the viewer application's menu bar when the document is active.
Parameter Description Default
hideMenubar
Set to true to hide the menu bar.
false
function setHideWindowUi(hideWindowUi)
Specify whether to hide user interface elements in the document's window (such as scroll bars and navigation controls), leaving only the document's contents displayed.
Parameter Description Default
hideWindowUi
Set to true to hide ui elements.
false
function setFitWindow(fitWindow)
Specify whether to resize the document's window to fit the size of the first displayed page.
Parameter Description Default
fitWindow
Set to true to resize the window.
false
function setCenterWindow(centerWindow)
Specify whether to position the document's window in the center of the screen.
Parameter Description Default
centerWindow
Set to true to center the window.
false
function setDisplayTitle(displayTitle)
Specify whether the window's title bar should display the document title. If false , the title bar should instead display the name of the PDF file containing the document.
Parameter Description Default
displayTitle
Set to true to display the title.
false
function setRightToLeft(rightToLeft)
Set the predominant reading order for text to right-to-left. This option has no direct effect on the document's contents or page numbering but can be used to determine the relative positioning of pages when displayed side by side or printed n-up
Parameter Description Default
rightToLeft
Set to true to set right-to-left reading order.
false

 

Miscellaneous

function setDebugLog(debugLog)
Turn on the debug logging. Details about the conversion are stored in the debug log. The URL of the log can be obtained from the getDebugLogUrl method or available in conversion statistics.
Parameter Description Default
debugLog
Set to true to enable the debug logging.
false
function getDebugLogUrl()
Get the URL of the debug log for the last conversion.
Returns
  • string - The link to the debug log.
function getRemainingCreditCount()
Get the number of conversion credits available in your account.
This method can only be called after a call to one of the convertXYZ methods.
The returned value can differ from the actual count if you run parallel conversions.
The special value 999999 is returned if the information is not available.
Returns
  • int - The number of credits.
function getConsumedCreditCount()
Get the number of credits consumed by the last conversion.
Returns
  • int - The number of credits.
function getJobId()
Get the job id.
Returns
  • string - The unique job identifier.
function getPageCount()
Get the total number of pages in the output document.
Returns
  • int - The page count.
function getOutputSize()
Get the size of the output in bytes.
Returns
  • int - The count of bytes.
function setTag(tag)
Tag the conversion with a custom value. The tag is used in conversion statistics. A value longer than 32 characters is cut off.
Parameter Description Default
tag
A string with the custom tag.

 

API Client Options

function setUseHttp(useHttp)
Specifies if the client communicates over HTTP or HTTPS with Pdfcrowd API.
Parameter Description Default
useHttp
Set to true to use HTTP.
false
function setUserAgent(userAgent)
Set a custom user agent HTTP header. It can be usefull if you are behind some proxy or firewall.
Parameter Description Default
userAgent
The user agent string.
pdfcrowd_nodejs_client/4.9.0 (http://pdfcrowd.com)
function setProxy(host, port, userName, password)
Specifies an HTTP proxy that the API client library will use to connect to the internet.
Parameter Description Default
host
The proxy hostname.
port
The proxy port.
userName
The username.
password
The password.
function setRetryCount(retryCount)
Specifies the number of retries when the 502 HTTP status code is received. The 502 status code indicates a temporary network issue. This feature can be disabled by setting to 0.
Parameter Description Default
retryCount
Number of retries wanted.
1