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Making your first API v4 call with POSTMAN

You can download our Postman collection here.
Postman allows you to easily test all the API endpoints without developing and coding.

In this tutorial, we will cover basics so you can start within few minutes with your very own PDF:
Generation of your own temporary token
Setting up the Postman app
Input the JWT token to the Postman app
Generate your first PDF document with your JSON data using Postman

JWT introduction, definition
Generate your first template using Postman

Generation of your own temporary token

You can create a temporary token on the Settings page after you login to PDF Generator API. The generated token uses your email address as the subject (sub) value and is valid for 15 minutes. These test tokens should never be used in production applications.

Generate Temporary JWT in Settings

Setting up the Postman App

You can download Postman collection for PDF Generator API here.
After the import, in the left sidebar, you should be able to see the list of all different requests, copying the logic in our API documentantion

postman list

Input the JWT token to the Postman app

JWT token import

Click on "Authorization" tab, then choose type "Bearer token" and insert copied token.

Generate your first PDF document

Merges template with data and returns a public URL to a PDF document. You should send the JSON encoded data in request body as the data parameter. After the request is send, the URL for the generated document is returned. You can read more about all the parameters in our API documentantion.

You will need ID of your template first, in our example this is 717658.

Secondly, you will need JSON data, an example for the Certificate template could be found here:
{"Name":"John Smith","DueDate":"2020-07-01"}

And lastly, you will place JSON data into "Body" part:

  "template": {
    "id": 717658,
    "data": {"Name":"John Smith","DueDate":"2020-07-01"}
  "format": "pdf",
  "output": "url",
  "name": "certificate 123"

You can now press the button "Send".
The system will now generate PDF with your JSON data and get back URL for the PDF.

This can be open on a new tab

Hooray! Your first PDF document is generated!


JWT introduction, definition

JSON Web Tokens are composed of three sections: a header, a payload (containing a claim set), and a signature. The header and payload are JSON objects, which are serialized to UTF-8 bytes, then encoded using base64url encoding.

The JWT's header, payload, and signature are concatenated with periods (.). As a result, a JWT typically takes the following form:

{Base64url encoded header}.{Base64url encoded payload}.{Base64url encoded signature}

Generation of your own token


Property alg defines which signing algorithm is being used. PDF Generator API users HS256. Property typ defines the type of token and it is always JWT.

  "alg": "HS256",
  "typ": "JWT"


The second part of the token is the payload, which contains the claims or the pieces of information being passed about the user and any metadata required. It is mandatory to specify the following claims:

issuer (iss): Your API key
subject (sub): Workspace identifier
You can also specify the token expiration time (exp) which is timestamp in seconds since Epoch (unix epoch time). It is highly recommended to set the exp timestamp for a short period, i.e. a matter of seconds. This way, if a token is intercepted or shared, the token will only be valid for a short period of time.

  "iss": "ad54aaff89ffdfeff178bb8a8f359b29fcb20edb56250b9f584aa2cb0162ed4a",
  "sub": "",
  "exp": 1586112639


To create the signature part you have to take the encoded header, the encoded payload, a secret, the algorithm specified in the header, and sign that. The signature is used to verify the message wasn't changed along the way, and, in the case of tokens signed with a private key, it can also verify that the sender of the JWT is who it says it is.

    base64UrlEncode(header) + "." +

Putting all together

The output is three Base64-URL strings separated by dots. The following shows a JWT that has the previous header and payload encoded, and it is signed with a secret.

In the it should looks like this:

In case you would like to learn more about the background of the JWT or get more inputs how you can use it - website here

Create a template using Postman - your first API call

After the request is send, the template of your ID is returned back via the JSON file.

Create Template

Updated on: 08/09/2023

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