Although my previous comment about the apim.output function argument is valid in that it should describe the output that you're writing, ie, text/plain instead of */*, it is not the cause of your issue. The cause is a simple case sensitivity issue. In v5, request headers are saved internally with lower cased names, and apim.getvariable is case sensitive. Simply change
var store = apim.getvariable('request.headers.Authorization');
to
var store = apim.getvariable('request.headers.authorization');
and your header value should be available to you.
Regards,
Steve
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Steve Linn
Senior Consulting I/T Specialist
IBM
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