In the dynamic landscape of API Testing, maintaining an authenticated session is a bit challenging. The following guide dives deeper into how you can automate the process of refreshing your authentication token using Postman scripting feature, ensuring your API request are always authenticated without manual intervention
Step 1: Setting up your workspace and collection
Begin by creating a new workspace where you API collections will reside, within this create a new collection folder, this serves as the home for all the API calls including login request.
Step 2: Setting Up the Environment
create the environment for this API and configure the variables ,you can add essential variables like base URL, email, password, AUTH Token, etc. also postman allows you to hide the sensitive information by setting it to secret
Step 3: Crafting the login API calls
The POST request not only authenticates the session but also stores the resulting token as variable.
Create a API call for you login request using POST.
In the request body provide necessary credentials or payload for login.
In the Test tab of the login request add the script to parse the response and store the authentication token in the environmental variable this could look something like this:
By setting up the login request in this manner ,you ensure that every successful authentication automatically updates the environment variable with the new token.
Step 4: Automating the environment variables across the collection
To leverage the token stored from your login call across other API request within the collection follow the below steps:
Create the pre-request script across the collection level:
Navigate to your collection settings and insert the pre-request script that runs any request within the collection here is the example script
Step 4: Set authorization at collection level and folder level
Set the authorization at collection level to the bearer token for the the type from the dropdown and token to the variable that is be set like the one below:
Set the authorization for the other folders of collection to inherit auth from parent or set it explicitly use the token variable ,ensure all contained request authenticate using stored token
By implementing the above setup, you achieve a streamlined testing process. The pre-request script at the collection level ensures that the login token is refreshed and applied across all the API calls across within the collection ,eliminating the need of repeated login request and manual token updates. This automated approach not only saves the time but also reduce the potential of error, making your API testing more efficient and reliable.