Sender Rest adapter Get operation processing

[Former Member]

Hi All,

I have a scenario where I need to host a REST service using GET operation and there are 2 optional parameters (let's call them a and b).

Since this is GET operation, I am not expecting any HTTP payload in body. I have configured the sender rest channel to convert data to XML and add wrapper of Message type name (refer screenshots). I have done request mapping to hard code a few parameters.

However, if I send a GET message to the service using a rest client with no payload, I receive an error (MP: exception caught with cause com.sap.aii.adapter.xi.routing.RoutingException: Unable to parse XML message payload to extract operation for receiver determinationorg.xml.sax.SAXParseException: Premature end of file.). PI doesn't seem to like empty HTTP body even in case of GET operation.

Also noticed that:

1. REST adapter does not add the wrapper element to the request message, if there is no content in body. I would have though it would create an empty root level tag with message type name.
2. If I change the option to POST and pass {}, as HTTP body, my interface works fine.

Am I doing something wrong here?

Regards,

Sanjeev.

Message was edited by: Sanjeev Shekhar Singh

[bhavesh_kantilal · Accepted solution]

I dont have a REST adapter on my landscape and hence while not a direct answer, Why not use the plain HTTP_AAE Adapter with the GET method?

[Former Member · Accepted solution]

Thanks Bhavesh,

I have to return the response as JSON and also response volume is a bit high, so didn't want to tinker around with Java mapping too much to perform conversion. But I agree, this is an alternative.

My main intention was to understand if this is the intended behavior of rest adapter (not handling empty payload for GET operation), or am I doing something wrong in the configuration.

Regards,

Sanjeev

[bhavesh_kantilal · Accepted solution]

I definitely understand the need to use a Standard Approach. Would have also done the same.

What you require from the REST Adapter that it accepts a Empty Payload for a HTTP GET seems to be a valid ask! From the looks of your error, it doesnt seem to be acceptable to PI ( I wish I could try this ) and hence a OSS to SAP might be the answer

Regards

Bhavesh

[bhavesh_kantilal · Accepted solution]

I just checked my notes for a previous REST Demo and I was actually able to use a REST Scenario with a GET call with no payload.Below is what my configuration looks like,

Is this the same configuration you use? If yes,Would suggest if there are any patches around the same, have a look on Service Market Place.

[bhavesh_kantilal · Accepted solution]

Sorry for multiple responses but have you set the Operation Determination in your REST Adapter?

[Former Member · Accepted solution]

Thanks Bhavesh,

I haven't tried the Operation Determination part. Will check it tomorrow and update the thread with results.

Thanks,

Sanjeev

[Former Member · Accepted solution]

Bang on Bhavesh. Using Operation determination did the trick.

Thanks,

Sanjeev.