Get OData $metadata in JSON format

I agreed with the previous answer. This isn't supported by the specification but some OData frameworks / libraries are about to implement this feature.

I think about Olingo. This is could be helpful for you if you also implement the server side. See this issue in the Olingo JIRA for more details:

• OLINGO-570 - https://issues.apache.org/jira/browse/OLINGO-570

Hope it helps you, Thierry

You can use jQuery to get the relevant information from an OData service $metadata.

Take for example:
You write a unit test to check the OData entities property names matches with your application entities. Then you have to retrieve the properties of the OData entity.

$.ajax({
            type: "GET",
            url: "/destinations/odata-service/$metadata",
            beforeSend: function() {
                console.log("before send check");
            },
            dataType: "xml",
            contentType: "application/atom+xml",
            context: document.body,
            success: function(xml) {
                console.log("Success ResourceTypes");   
                var ODataTypeINeed = $(xml).find('EntityType').filter(function(){ 
                                         return $(this).attr('Name') == 'ODataTypeINeed'
                                    });                 
                $(ODataTypeINeed).find('Property').each(function() {
                    console.log($(this).attr('Name')); //List of OData Entity properties
                });
            },
            error: function(err) {
                console.log(err);
            }
 });

As an alternative to ?$format=json, you could also just set the following two headers :

• Accept: application/json
• Content-Type: application/json; charset=utf-8

I'm not sure which is the minimum Odata version required, but this works perfectly for me on Microsoft Dynamics NAV 2016, which uses Odata v4.

The $metadata document is in the CSDL format, which currently only has an XML representation. (As a side note, if you do want to request the json format for a different kind of OData payload, make sure the format query token has a $ in front of it: $format=json.)

So, no it is not possible. You can, however, get the service document in JSON, which is a subset of the $metadata document:

http://odata.informea.org/services/odata.svc?$format=json

This won't have type information, but it will list the available entry points of the service (i.e., the entity sets).