FileMaker and JSON Files

FileMaker introduced its JSON functions in version 16. They’ve changed how many developers work, both as a protocol for handling data interchange within FileMaker and working with external APIs. The JSON functions are for working with text, but what if we run into a situation where we need to work with actual JSON files? Does FileMaker provide the tools to read and write .json files as well as JSON text?

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Looking for our article and example file on the JSON Parsing Function? Here it is: FileMaker JSON Functons.

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FileMaker JSON: Reading Files

JSON files are really utf-8 text files, and we have a few different ways of handling them in FileMaker.

The Insert From URL script step can be used to insert .json files that are local to the system or downloaded from an external site or API. The way these files are inserted depends on the target that’s specified in the script step. For example, if a variable or text field is specified as the target, then Insert From URL will simply read the .json file and insert it as text. As text, we can then use the JSONGetElement function to parse the specific values.

If a container field is specified as the target in the Insert From URL step, then the .json file is inserted into the container as an actual JSON file.

Since .json files are actually utf-8 encoded text files, we can read the text right from the container using the TextDecode function and specifying utf-8 as the encoding. However, it’s also possible these .json files are getting into the container field using a method that’s not Insert From URL, and the option of specifying the target is not available. Hence, the TextDecode function is useful in that scenario as well.

Writing JSON Files from FileMaker

There are also scenarios where you may want to store or send your JSON from FileMaker as a .json file rather than as text. For example, some APIs recommend that you upload a .json file if the payload is very large instead of writing the JSON text inline as part of your request.

Let’s say we want to create the following JSON from FileMaker data and then turn it into a .json file.

{
    "contact" : 
    {
        "email1" : "support@seedcode.com",
        "email2" : "support@dayback.com",
        "phone" : "855-733-3263"
    },
    "name" : "Jason Young",
    "title" : "Developer"
}

The first thing we’ll do is to create the JSON with our JSONSetElement function like this.

JSONSetElement ( "{}" ; 


	[ "name" ; "Jason Young" ; JSONString ];
	[ "title" ; "Developer" ; JSONString ];
	[ "contact" ; JSONSetElement ( "{}" ;
		[ "phone" ; "855-733-3263" ; JSONString ];
		[ "email1" ; "support@seedcode.com" ; JSONString ];
		[ "email2" ; "support@dayback.com" ; JSONString ] )
	; JSONObject ]
	

)

If we’re using FileMaker client, we can set the JSON into a text field and then use Export Field Contents and specify the file name with the .json extension and then re-insert the file into our container: we’re all set. However, if we want this to run on the server or WebDirect, we need to handle this differently as Export Field Contents is unavailable on the server and is limited on WebDirect. As discussed earlier, .json files are just utf-8 text files, so we can use the TextEncode function to convert our JSON text to a file. When we do this, we get a file named utf-8.txt, but we need this to be a .json file with a specific name. To change the file name and extension, we can encode the file as Base64 and then decode it and specify the file name with the Base64Decode function’s optional second parameter. Here’s an example script showing how we can create the .json file with the name Example2.json.

We now have a properly encoded .json file ready for an API or for storing as a file.

Conclusions