Using Postman Environments and Tests with the FileMaker Data API

One of the new features of FileMaker Server 16 and FileMaker Cloud 1.16.0 is the FileMaker Data API – currently in trial mode which expires on September 27, 2018. The FileMaker Data API is an application programming interface (API) that allows web services to access data in hosted FileMaker solutions and conforms to Representational State Transfer (REST) architecture, making the FileMaker Data API a REST API.

You can use the Data API to integrate your FileMaker solutions with other applications and services – REST APIs are the current standard for integration and the Data API will be the replacement for the current XML and PHP APIs.

Your web service or application calls the FileMaker Data API to obtain an authentication token for access to a hosted solution, then uses that token in subsequent calls to create records, update records, delete records, and perform find requests.The FileMaker Data API returns data in JavaScript Object Notation (JSON), another standard that is used with REST APIs for data formatting (and is also supported by FileMaker Pro v16).

A great tool to use when testing REST calls with the Data API is Postman, a free app for macOS, Windows and Linux (paid versions are also available). Postman allows you to make requests (GET, POST, PUT etc) to a REST API like the FileMaker Data API and inspect the response, including the headers. You can quickly make changes to the requests and headers that you send and compare the results – when working with REST APIs a tool like Postman is indispensable.

As mentioned above the FileMaker Data API requires you to obtain an authentication token when first accessing a FileMaker solution – the access token is valid until you log out of a solution or for 15 minutes after the last call that specified the token. While the token is valid, each call that specifies the token resets the session timeout counter to zero. To save you from having to manually copy and paste your token with each new request you can use some features of Postman to save your from having to manually update any variables in your requests manually, including the Data API access token.

Postman lets you setup multiple “environments” that can contain multiple variables fore each environment, such as the host address URL. For example you might have a development environment and a production environment, each with their own host address and other variables. In Postman I would simply have a POST request URL like this:

https://{{server}}/fmi/rest/api/auth/Tasks

and in each Postman environment I would specify the value for the {{server}} variable. When you make your request by hitting the Send button in Postman it will insert the appropriate value for each variable you’ve specified. You can read all about setting up Postman environments and variables in the Postman docs.

As you can’t specify the Data API access token in advance you can use another great feature of Postman to dynamically create the token variable which is then used in subsequent API requests. Your initial request to authenticate/login will look like this:

{ "user":"admin", "password":"admin", "layout":"Tasks" }

and if successful the response will look like this:

{ "errorCode": "0", "layout": "Tasks", "token": "fdde29fa175eb1cc8347512ca327b191619fc32ed65efaab26d8" }

Using the Tests feature when making a Postman request you can execute some JavaScript code after the request is sent to dynamically create a token variable that you can use with your subsequent API calls without having to copy and paste the token each time. Here’s a screenshot of how you would set this up in Postman for the Data API authentication request:

The JavaScript code you can copy/paste is:

var data = JSON.parse(responseBody);
postman.setEnvironmentVariable("token", data.token)

Using Postman environments and Tests to update the token variable makes working with the FileMaker Data API much easier and should save you a lot of time.