IgnoreUnresolvedVariable Property issue in ServiceCallout

[ahemanna]

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ServiceCallout async="false" continueOnError="false" enabled="true" name="SC">
    <DisplayName>SC</DisplayName>
    <Properties/>
    <Request clearPayload="false" variable="myRequest">
        <IgnoreUnresolvedVariables>true</IgnoreUnresolvedVariables>
                <Copy source="request">
             <Headers>
            <Header name="Content-Type">{request.header.Content-Type}</Header>
            </Headers>
            <QueryParams/>
        </Copy>
    </Request>
    <Response>calloutResponse</Response>
    <HTTPTargetConnection>
        <URL>http://This is a dummy endpoint</URL>
    </HTTPTargetConnection>
</ServiceCallout>

We are trying to copy content-type header from the request .In a scenario where the header is not passed in the request we get the below error inspite of having <IgnoreUnresolvedVariables>true</IgnoreUnresolvedVariables>

Error:Unresolved variable : request.header.Content-Type

Is this a bug or an expected behavior?

@Dino-at-Google @Dino @Anil Sagar @ Google @Siddharth Barahalikar

[sidd-harth]

I have used the same config and see no issue. Which Apigee version are you working on Cloud/On-prem?

[ahemanna]

We are using cloud version.

We're seeing the issue when there's no content-type passed in the request.

[#4]

I tried the same in the cloud version. It works for me and I don't see any error. This looks like your target in the service-callout is expecting the content-type and the error is returning back from the target. Can you try changing the target to the one which doesn't expect any content type?

[ahemanna]

I verified and could tell the error was not from target. I validated the same on my trial org and this does indeed work fine. I'll have a ticket raised with Apigee on this for more info. Thank you.

[#6]

can you try setting this through another assign message policy before the service-callout? You may find the error where happens.

[ahemanna]

Yes, I was able to move on by setting the content type in one of the JS policies just before the service callout.

[#8]

does that resolve your issue?

[ahemanna]

_{Yes, that did solve the issue. But out of curiosity I reverted it to the original configuration and now I see it working too... Could it be that the changes were not synced across all MPs?}

[#10]

that could be some dirty read.