HTML to Image / Node.js Reference

class HtmlToImageClient

All setter methods return HtmlToImageClient object unless specified otherwise.

Constructor

function HtmlToImageClient(userName, apiKey)

Constructor for the PDFCrowd API client.

Parameters:
  • userName - Your username at PDFCrowd.
  • apiKey - Your API key.

Conversion Format

function setOutputFormat(outputFormat)

The format of the output file.

Parameter:
  • outputFormat
    Allowed Values:
    • png
    • jpg
    • gif
    • tiff
    • bmp
    • ico
    • ppm
    • pgm
    • pbm
    • pnm
    • psb
    • pct
    • ras
    • tga
    • sgi
    • sun
    • webp
    Default:
    png

Conversion Input

function convertUrl(url, callbacks)

Convert a web page.

Parameters:
  • url - The address of the web page to convert.
    Constraint:
    • Supported protocols are http:// and https://.
  • 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
    • sendImageInHttpResponse(response, contentType, fileName[, disposition]) - sends the generated image in an HTTP response
      • response - the response object
      • contentType - the response content type
      • fileName - the desired file name
      • disposition - the response content disposition, can be "attachment" or "inline", the default is "attachment".

function convertUrlToFile(url, filePath, callback)

Convert a web page and write the result to a local file.

Parameters:
  • url - The address of the web page to convert.
    Constraint:
    • Supported protocols are http:// and https://.
  • filePath - The output file path.
  • 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 convertFile(file, callbacks)

Convert a local file.

Parameters:
  • file - The path to a local file to convert.
    The file can be either a single file or an archive (.tar.gz, .tar.bz2, or .zip).
    If the HTML document refers to local external assets (images, style sheets, javascript), zip the document together with the assets.
    Constraints:
    • The file must exist and not be empty.
    • The file name must have a valid extension.
  • 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
    • sendImageInHttpResponse(response, contentType, fileName[, disposition]) - sends the generated image in an HTTP response
      • response - the response object
      • contentType - the response content type
      • fileName - the desired file name
      • disposition - the response content disposition, can be "attachment" or "inline", the default is "attachment".

function convertFileToFile(file, filePath, callback)

Convert a local file and write the result to a local file.

Parameters:
  • file - The path to a local file to convert.
    The file can be either a single file or an archive (.tar.gz, .tar.bz2, or .zip).
    If the HTML document refers to local external assets (images, style sheets, javascript), zip the document together with the assets.
    Constraints:
    • The file must exist and not be empty.
    • The file name must have a valid extension.
  • filePath - The output file path.
  • 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 convertString(text, callbacks)

Convert a string.

Parameters:
  • text - The string content to convert.
  • 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
    • sendImageInHttpResponse(response, contentType, fileName[, disposition]) - sends the generated image in an HTTP response
      • response - the response object
      • contentType - the response content type
      • fileName - the desired file name
      • disposition - the response content disposition, can be "attachment" or "inline", the default is "attachment".

function convertStringToFile(text, filePath, callback)

Convert a string and write the output to a file.

Parameters:
  • text - The string content to convert.
  • filePath - The output file path.
  • 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 convertStream(inStream, callbacks)

Convert the contents of an input stream.

Parameters:
  • inStream (InputStream) - The input stream with source data.
    The stream can contain either HTML code or an archive (.zip, .tar.gz, .tar.bz2).
    The archive can contain HTML code and its external assets (images, style sheets, javascript).
  • 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
    • sendImageInHttpResponse(response, contentType, fileName[, disposition]) - sends the generated image in an HTTP response
      • response - the response object
      • contentType - the response content type
      • fileName - the desired file name
      • disposition - the response content disposition, can be "attachment" or "inline", the default is "attachment".

function convertStreamToFile(inStream, filePath, callback)

Convert the contents of an input stream and write the result to a local file.

Parameters:
  • inStream (InputStream) - The input stream with source data.
    The stream can contain either HTML code or an archive (.zip, .tar.gz, .tar.bz2).
    The archive can contain HTML code and its external assets (images, style sheets, javascript).
  • filePath - The output file path.
  • 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 setZipMainFilename(filename)

Set the file name of the main HTML document stored in the input archive. If not specified, the first HTML file in the archive is used for conversion. Use this method if the input archive contains multiple HTML documents.

Parameter:
  • filename - The file name.

Image Output

function setScreenshotWidth(width)

Set the output image width in pixels.

Parameter:
  • width (int)
    Constraint:
    • The accepted range is 96-65000.
    Default:
    1024
Example:
  • Full HD width: setScreenshotWidth(1920)

function setScreenshotHeight(height)

Set the output image height in pixels. If it is not specified, actual document height is used.

Parameter:
  • height (int)
    Constraint:
    • Must be a positive integer.
Example:
  • Full HD height: setScreenshotHeight(1080)

function setScaleFactor(factor)

Set the scaling factor (zoom) for the output image.

Parameter:
  • factor (int) - The percentage value.
    Constraint:
    • Must be a positive integer.
    Default:
    100
Example:
  • Reduce image for thumbnails: setScaleFactor(50)

function setBackgroundColor(color)

The output image background color.

Availability:
API client >= 5.0.0, converter >= 20.10. See versioning.
Parameter:
  • color
    Constraint:
    • The value must be in RRGGBB or RRGGBBAA hexadecimal format.
Examples:
  • red color: setBackgroundColor("FF0000")
  • fully transparent background: setBackgroundColor("00000000")
  • green color with 50% opacity: setBackgroundColor("00ff0080")
  • green color: setBackgroundColor("00ff00")

General Options

function setUsePrintMedia(value)

Use the print version of the page if available (@media print).

Parameter:
  • value (bool) - Set to true to use the print version of the page.
    Default:
    false

function setNoBackground(value)

Do not print the background graphics.

Parameter:
  • value (bool) - Set to true to disable the background graphics.
    Default:
    false

function setDisableJavascript(value)

Do not execute JavaScript.

Parameter:
  • value (bool) - Set to true to disable JavaScript in web pages.
    Default:
    false

function setDisableImageLoading(value)

Do not load images.

Parameter:
  • value (bool) - Set to true to disable loading of images.
    Default:
    false

function setDisableRemoteFonts(value)

Disable loading fonts from remote sources.

Parameter:
  • value (bool) - Set to true disable loading remote fonts.
    Default:
    false

function setUseMobileUserAgent(value)

Deprecated Replaced with: setConverterUserAgent

Use a mobile user agent.

Availability:
API client >= 5.3.0, converter >= 20.10. See versioning.
Parameter:
  • value (bool) - Set to true to use a mobile user agent.
    Default:
    false

function setLoadIframes(iframes)

Specifies how iframes are handled.

Availability:
API client >= 5.0.0, converter >= 20.10. See versioning.
Parameter:
  • iframes
    Allowed Values:
    • all — All iframes are loaded.
    • same-origin — Only iframes with the same origin as the main page are loaded.
    • none — Iframe loading is disabled.
    Default:
    all

function setBlockAds(value)

Try to block ads. Enabling this option can produce smaller output and speed up the conversion.

Parameter:
  • value (bool) - Set to true to block ads in web pages.
    Default:
    false

function setDefaultEncoding(encoding)

Set the default HTML content text encoding.

Parameter:
  • encoding - The text encoding of the HTML content.
    Default:
    auto detect
Examples:
  • Set to use Latin-2 encoding: setDefaultEncoding("iso8859-2")
  • Set to use UTF-8 encoding: setDefaultEncoding("utf-8")

function setLocale(locale)

Set the locale for the conversion. This may affect the output format of dates, times and numbers.

Availability:
API client >= 5.0.0, converter >= 20.10. See versioning.
Parameter:
  • locale - The locale code according to ISO 639.
    Default:
    en-US
Example:
  • Set to use Japanese locale: setLocale("ja-JP")

function setHttpAuth(userName, password)

Set credentials to access HTTP base authentication protected websites.

Parameters:
  • userName - Set the HTTP authentication user name.
  • password - Set the HTTP authentication password.

function setCookies(cookies)

Set HTTP cookies to be included in all requests made by the converter.

Parameter:
  • cookies - The cookie string.
Example:
  • Multiple cookies for authentication: setCookies("session=6d7184b3bf35;token=2710")

function setVerifySslCertificates(value)

Do not allow insecure HTTPS connections.

Parameter:
  • value (bool) - Set to true to enable SSL certificate verification.
    Default:
    false

function setFailOnMainUrlError(failOnError)

Abort the conversion if the main URL HTTP status code is greater than or equal to 400.

Parameter:
  • failOnError (bool) - Set to true to abort the conversion.
    Default:
    false

function setFailOnAnyUrlError(failOnError)

Abort the conversion if any of the sub-request HTTP status code is greater than or equal to 400 or if some sub-requests are still pending. See details in a debug log.

Parameter:
  • failOnError (bool) - Set to true to abort the conversion.
    Default:
    false

function setNoXpdfcrowdHeader(value)

Do not send the X-Pdfcrowd HTTP header in PDFCrowd HTTP requests.

Parameter:
  • value (bool) - Set to true to disable sending X-Pdfcrowd HTTP header.
    Default:
    false

function setCustomCss(css)

Apply custom CSS to the input HTML document. It allows you to modify the visual appearance and layout of your HTML content dynamically. Tip: Using !important in custom CSS provides a way to prioritize and override conflicting styles.

Availability:
API client >= 5.14.0, converter >= 20.10. See versioning.
Parameter:
  • css - A string containing valid CSS.
Examples:
  • Set the page background color to gray: setCustomCss("body { background-color: gray; }")
  • Do not show nav HTML elements and the element with ad-block ID in the output PDF: setCustomCss("nav, #ad-block { display: none !important; }")

function setCustomJavascript(javascript)

Run a custom JavaScript after the document is loaded and ready to print. The script is intended for post-load DOM manipulation (add/remove elements, update CSS, ...). In addition to the standard browser APIs, the custom JavaScript code can use helper functions from our JavaScript library.

Parameter:
  • javascript - A string containing a JavaScript code.
Example:
  • Set the page background color to gray: setCustomJavascript("document.body.style.setProperty('background-color', 'gray', 'important')")

function setOnLoadJavascript(javascript)

Run a custom JavaScript right after the document is loaded. The script is intended for early DOM manipulation (add/remove elements, update CSS, ...). In addition to the standard browser APIs, the custom JavaScript code can use helper functions from our JavaScript library.

Parameter:
  • javascript - A string containing a JavaScript code.
Example:
  • Set the page background color to gray: setOnLoadJavascript("document.body.style.setProperty('background-color', 'gray', 'important')")

function setCustomHttpHeader(header)

Set a custom HTTP header to be included in all requests made by the converter.

Parameter:
  • header
    Constraint:
    • A string containing the header name and value separated by a colon.
Example:
  • API client tracking header: setCustomHttpHeader("X-My-Client-ID:k2017-12345")

function setJavascriptDelay(delay)

Wait the specified number of milliseconds to finish all JavaScript after the document is loaded. Your license defines the maximum wait time by "Max Delay" parameter.

Parameter:
  • delay (int) - The number of milliseconds to wait.
    Constraint:
    • Must be a positive integer or 0.
    Default:
    200
Example:
  • Wait for 2 seconds: setJavascriptDelay(2000)

function setElementToConvert(selectors)

Convert only the specified element from the main document and its children. The element is specified by one or more CSS selectors. If the element is not found, the conversion fails. If multiple elements are found, the first one is used.

Parameter:
Examples:
  • The first element with the id main-content is converted: setElementToConvert("#main-content")
  • The first element with the class name main-content is converted: setElementToConvert(".main-content")
  • The first element with the tag name table is converted: setElementToConvert("table")
  • The first element with the tag name table or with the id main-content is converted: setElementToConvert("table, #main-content")
  • The first element <p class="article"> within <div class="user-panel main"> is converted: setElementToConvert("div.user-panel.main p.article")

function setElementToConvertMode(mode)

Specify the DOM handling when only a part of the document is converted. This can affect the CSS rules used.

Parameter:
  • mode
    Allowed Values:
    • cut-out — The element and its children are cut out of the document.
    • remove-siblings — All element's siblings are removed.
    • hide-siblings — All element's siblings are hidden.
    Default:
    cut-out

function setWaitForElement(selectors)

Wait for the specified element in a source document. The element is specified by one or more CSS selectors. The element is searched for in the main document and all iframes. If the element is not found, the conversion fails. Your license defines the maximum wait time by "Max Delay" parameter.

Parameter:
Examples:
  • Wait until an element with the id main-content is found: setWaitForElement("#main-content")
  • Wait until an element with the class name main-content is found: setWaitForElement(".main-content")
  • Wait until an element with the tag name table is found: setWaitForElement("table")
  • Wait until an element with the tag name table or with the id main-content is found: setWaitForElement("table, #main-content")
  • Wait until <p class="article"> is found within <div class="user-panel main">: setWaitForElement("div.user-panel.main p.article")

function setAutoDetectElementToConvert(value)

The main HTML element for conversion is detected automatically.

Availability:
API client >= 5.5.0, converter >= 20.10. See versioning.
Parameter:
  • value (bool) - Set to true to detect the main element.
    Default:
    false

function setReadabilityEnhancements(enhancements)

The input HTML is automatically enhanced to improve the readability.

Availability:
API client >= 5.5.0, converter >= 20.10. See versioning.
Parameter:
  • enhancements
    Allowed Values:
    • none — No enhancements are used.
    • readability-v1 — Version 1 of the enhancements is used.
    • readability-v2 — Version 2 of the enhancements is used.
    • readability-v3 — Version 3 of the enhancements is used.
    • readability-v4 — Version 4 of the enhancements is used.
    Default:
    none

Data

Methods related to HTML template rendering.

function setDataString(dataString)

Set the input data for template rendering. The data format can be JSON, XML, YAML or CSV.

Parameter:
  • dataString - The input data string.
Example:
  • Template variables for mail merge: setDataString("{"recipient": "Anna May", "sender": "John Doe"}")

function setDataFile(dataFile)

Load the input data for template rendering from the specified file. The data format can be JSON, XML, YAML or CSV.

Parameter:
  • dataFile - The file path to a local file containing the input data.
Example:
  • External data for template rendering: setDataFile("/home/user/john/data.json")

function setDataFormat(dataFormat)

Specify the input data format.

Parameter:
  • dataFormat - The data format.
    Allowed Values:
    • auto — the data format is auto detected
    • json
    • xml
    • yaml
    • csv
    Default:
    auto

function setDataEncoding(encoding)

Set the encoding of the data file set by setDataFile.

Parameter:
  • encoding - The data file encoding.
    Default:
    utf-8
Example:
  • Set to use Latin-2 encoding: setDataEncoding("iso8859-2")

function setDataIgnoreUndefined(value)

Ignore undefined variables in the HTML template. The default mode is strict so any undefined variable causes the conversion to fail. You can use {% if variable is defined %} to check if the variable is defined.

Parameter:
  • value (bool) - Set to true to ignore undefined variables.
    Default:
    false

function setDataAutoEscape(value)

Auto escape HTML symbols in the input data before placing them into the output.

Parameter:
  • value (bool) - Set to true to turn auto escaping on.
    Default:
    false

function setDataTrimBlocks(value)

Auto trim whitespace around each template command block.

Parameter:
  • value (bool) - Set to true to turn auto trimming on.
    Default:
    false

function setDataOptions(options)

Set the advanced data options:
  • csv_delimiter - The CSV data delimiter, the default is ,.
  • xml_remove_root - Remove the root XML element from the input data.
  • data_root - The name of the root element inserted into the input data without a root node (e.g. CSV), the default is data.
Parameter:
  • options - Comma separated list of options.
Examples:
  • Use semicolon to separate CSV data: setDataOptions("csv_delimiter=;")
  • Name the root of data rows and use the name in the template loop {% for row in rows %}...{% endfor %}: setDataOptions("data_root=rows")
  • Remove XML root so it the HTML template can be more simple: setDataOptions("xml_remove_root=1")

Miscellaneous

function setDebugLog(value)

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:
  • value (bool) - Set to true to enable the debug logging.
    Default:
    false

function getDebugLogUrl() { return string; }

Get the URL of the debug log for the last conversion.

Returns:
string - The link to the debug log.

function getRemainingCreditCount() { return int; }

Get the number of conversion credits available in your account.
This method can only be called after a call to one of the convertXtoY 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() { return int; }

Get the number of credits consumed by the last conversion.

Returns:
int - The number of credits.

function getJobId() { return string; }

Get the job id.

Returns:
string - The unique job identifier.

function getOutputSize() { return int; }

Get the size of the output in bytes.

Returns:
int - The count of bytes.

function getVersion() { return string; }

Get the version details.

Returns:
string - API version, converter version, and client version.

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:
  • tag - A string with the custom tag.
Example:
  • Track job in analytics: setTag("client-1234")

function setHttpProxy(proxy)

A proxy server used by the conversion process for accessing the source URLs with HTTP scheme. It can help to circumvent regional restrictions or provide limited access to your intranet.

Parameter:
  • proxy
    Constraint:
    • The value must have format DOMAIN_OR_IP_ADDRESS:PORT.
Examples:
  • Corporate proxy server: setHttpProxy("myproxy.com:8080")
  • Direct IP proxy connection: setHttpProxy("113.25.84.10:33333")

function setHttpsProxy(proxy)

A proxy server used by the conversion process for accessing the source URLs with HTTPS scheme. It can help to circumvent regional restrictions or provide limited access to your intranet.

Parameter:
  • proxy
    Constraint:
    • The value must have format DOMAIN_OR_IP_ADDRESS:PORT.
Examples:
  • Secure proxy for HTTPS: setHttpsProxy("myproxy.com:443")
  • Direct secure proxy IP: setHttpsProxy("113.25.84.10:44333")

function setClientCertificate(certificate)

A client certificate to authenticate the converter on your web server. The certificate is used for two-way SSL/TLS authentication and adds extra security.

Parameter:
  • certificate - The file must be in PKCS12 format.
    Constraint:
    • The file must exist and not be empty.
Example:
  • Custom CA certificate path: setClientCertificate("/home/user/john/pdfcrowd.crt")

function setClientCertificatePassword(password)

A password for PKCS12 file with a client certificate if it is needed.

Parameter:
  • password
Example:
  • PKCS12 certificate password: setClientCertificatePassword("123456")

Tweaks

Expert options for fine-tuning output.

function setMaxLoadingTime(maxTime)

Set the maximum time to load the page and its resources. After this time, all requests will be considered successful. This can be useful to ensure that the conversion does not timeout. Use this method if there is no other way to fix page loading.

Availability:
API client >= 5.15.0, converter >= 20.10. See versioning.
Parameter:
  • maxTime (int) - The number of seconds to wait.
    Constraint:
    • The accepted range is 10-30.

function setConverterUserAgent(agent)

Specifies the User-Agent HTTP header that will be used by the converter when a request is made to the converted web page.

Availability:
API client >= 6.4.0 See versioning.
Parameter:
  • agent - The user agent.
    Allowed Values:
    • chrome-desktop — The user-agent for desktop chrome corresponding to the converter used.
    • chrome-mobile — The user-agent for mobile chrome corresponding to the converter used.
    • latest-chrome-desktop — The user-agent of the recently released Chrome browser on desktops.
    • latest-chrome-mobile — The user-agent of the recently released Chrome browser on mobile devices.
    • custom string — A custom string for the user agent.
    Default:
    latest-chrome-desktop
Examples:
  • Mimic the recent chrome on mobiles: setConverterUserAgent("latest-chrome-mobile")
  • Mimic Safari 18.0 browser: setConverterUserAgent("Mozilla/5.0 (Macintosh; Intel Mac OS X 14_7_1) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.0 Safari/605.1.15")

API Client Options

function setConverterVersion(version)

Set the converter version. Different versions may produce different output. Choose which one provides the best output for your case.

Availability:
API client >= 5.0.0. See versioning.
Parameter:
  • version - The version identifier.
    Allowed Values:
    • 24.04 — Version 24.04.
    • 20.10 — Version 20.10.
    • 18.10 — Version 18.10.
    • latest — Version 20.10 is used.
    Default:
    24.04

function setUseHttp(value)

Specify whether to use HTTP or HTTPS when connecting to the PDFCrowd API.

Parameter:
  • value (bool) - Set to true to use HTTP.
    Default:
    false

function setClientUserAgent(agent)

Specifies the User-Agent HTTP header that the client library will use when interacting with the API.

Availability:
API client >= 6.4.0 See versioning.
Parameter:
  • agent - The user agent string.

function setUserAgent(agent)

Deprecated Replaced with: setClientUserAgent

Set a custom user agent HTTP header. It can be useful if you are behind a proxy or a firewall.

Parameter:
  • agent - The user agent string.
    Default:
    pdfcrowd_nodejs_client/6.5.2 (https://pdfcrowd.com)

function setProxy(host, port, userName, password)

Specifies an HTTP proxy that the API client library will use to connect to the internet.

Parameters:
  • host - The proxy hostname.
  • port (int) - The proxy port.
  • userName - The username.
  • password - The password.

function setRetryCount(count)

Specifies the number of automatic retries when the 502 or 503 HTTP status code is received. The status code indicates a temporary network issue. This feature can be disabled by setting to 0.

Parameter:
  • count (int) - Number of retries.
    Default:
    1
Example:
  • Retry failed requests three times: setRetryCount(3)