Parsing JSON Array in Azure APIM policy

Question

I need some help Parsing JSON Array in Azure APIM policy. My input to my API is a JSON Array but I want the output of the API to be JSON without the "[]", I just can't get the policy to remove them.

Here is the JSON Array input to my API:

[
{
"id": "myId",
"topic": "myTopic",
"subject": "/apis/test;Rev=1",
"data": {
"resourceUri": "myResourceUri"
},
"eventType": "Microsoft.ApiManagement.APIUpdated",
"dataVersion": "1",
"metadataVersion": "1",
"eventTime": "2022-09-08T14:22:46.7708654Z"
}
]

But I would like the Output of the policy to remove the square brackets [], like this:

{
"id": "myId",
"topic": "myTopic",
"subject": "/apis/test;Rev=1",
"data": {
"resourceUri": "myResourceUri"
},
"eventType": "Microsoft.ApiManagement.APIUpdated",
"dataVersion": "1",
"metadataVersion": "1",
"eventTime": "2022-09-08T14:22:46.7708654Z"
}

Here is my policy (which I copied from a tutorial and manipulated):

<policies>
<inbound>
<base />
<set-variable value="@(context.Request.Headers["Aeg-Event-Type"].Contains("SubscriptionValidation"))" name="isEventGridSubscriptionValidation" />
<set-variable value="@(context.Request.Headers["Aeg-Event-Type"].Contains("Notification"))" name="isEventGridNotification" />
<choose>
<when condition="@(context.Variables.GetValueOrDefault<bool>("isEventGridSubscriptionValidation"))">
<return-response>
<set-status code="200" reason="OK" />
<set-body>@{
var events = context.Request.Body.As<string>();
JArray a = JArray.Parse(events);
var eventGridData = a.First["data"];
var validationCode = eventGridData["validationCode"];
var jOutput =
new JObject(
new JProperty("validationResponse", validationCode)
);
return jOutput.ToString();
}</set-body>
</return-response>
</when>
<when condition="@(context.Variables.GetValueOrDefault<bool>("isEventGridNotification"))">
<send-one-way-request mode="new">
<set-url>https://hooks.slack.com/services/mySlackHandle</set-url>
<set-method>POST</set-method>
<set-body>@{
var events = context.Request.Body.As<string>();
JArray a = JArray.Parse(events);
var eventGridData = a.First["data"];
var song = eventGridData["song"];
return new JObject(
new JProperty("text", String.Format(" {1}",
song, a))).ToString();
}</set-body>
</send-one-way-request>
<return-response>
<set-status code="200" reason="OK" />
</return-response>
</when>
</choose>
</inbound>
<backend>
<base />
</backend>
<outbound>
<base />
</outbound>
<on-error>
<base />
</on-error>
</policies>

ANY HELP GREATLY APPRECIATED! Extra points if you can remove the reference to "song", which I cannot without breaking the policy...

Answer 1

@RapidJames Thank you for reaching out to Microsoft Q&A. Assuming you want to simply remove "[]" from JArray, you can try the sample policy below:

<set-body>@{  
            var sampleBody = context.Request.Body.As<string>();  
            JArray jValue = JArray.Parse(sampleBody);   
            return String.Join("", jValue.Select(i => i.ToString()));  
        }  
</set-body>  

This policy simply loops through all Children in JArray and converts into a string output as you were looking for.

Sample Output:

If you are looking to remove a specific child, you can add condition "Where" using Linq expression. Feel free to explore JArray class for reference on this. Sorry I couldn't understand about song reference you mentioned and please clarify if you need help with that. I would be happy to assist you.

I hope this answers your question and feel free to add if you have any questions. Please 'Accept as answer' and ‘Upvote’ if it helped so that it can help others in the community.