Java-wiremock: Correctly handle multiple MIME-types in HTTP-Accept-headers

[jheyens]

In case of an endpoint that may reply with multiple Content-Types (e.g. a file as application/octet-stream if successful and an error message as application/json in case of an error), the Wiremock stubs create the following snippet:

[...]
.withHeader("Accept", havingExactly("application/octet-stream", "application/json"))
[...]

This results in a failed request if there are not at least to "Accept: "-headers, one being exactly Accept: application/octet-stream, the other being exactly Accept: application/json. This, however, is not how user agents set the "Accept: "-Header. Instead, they supply only one Header containing both (separated by , plus optional whitespace).

This PR replaces the lines like

.withHeader("Accept", havingExactly("application/octet-stream", "application/json"))

with one line for each requested header like this:

.withHeader("Accept", containing("application/octet-stream"))
.withHeader("Accept", containing("application/json"))

The switch from havingExactly to containing is due to shortcomings in the wiremock DSL, which would require specification-compliant parsing of the "Accept: "-Header content. I don't think that would be worth the trouble, though, since substring matching ought to be enough for test suites.

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[wing328]

thanks for the PR

cc acouvreur - author of Java Wiremock generator

[wing328]

thanks for the PR

let's give it a try