[swift5 client] fix filename for binary downloads

[gretzki]

Problem:

When a file download is handled within URLSessionImplementations,
the filename is retrieved via the header Content-Disposition part of the response.
The header is looked for an entry starting with filename=.
But the search is skipped too early, since the loop is exited if the first iteration does not match.

Example:

Try to download a file with a swift5 client for a spec like this:

  /PublicDocument/Download:
    get:
      tags:
        - Public Area
      description: 'Document Download for Public Documents. Login not Required'
      parameters:
        - $ref: '#/components/parameters/queryId'
      responses:
        '200':
          description: 'OK'
          content:
            application/pdf:
              schema:
                type: string
                format: binary

When downloading from a server, the response header could have an answer like so:

Content-Disposition: attachment; filename=downloaded.pdf; filename*=UTF-8''downloaded.pdf

There, the server says to use downloaded.pdf as filename. But the actual implementation of the swift5 client will exit after checking attachment and won't find filename= in the next section (separated by semicolon).

Solution:

Simply replacing break with continue in the matching logic inside the loop fixes the algorithm.

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  ./mvnw clean package 
  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh
  

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  @jgavris, @ehyche, @Edubits, @jaz-ah, @4brunu

[4brunu]

@gretzki Thanks for your contribution.
Could you please also fix this in the AlamofireImplementations?

openapi-generator/modules/openapi-generator/src/main/resources/swift5/libraries/alamofire/AlamofireImplementations.mustache

Lines 276 to 288 in 1d64822

	for contentItem in items {
	let filenameKey = "filename="
	guard let range = contentItem.range(of: filenameKey) else {
	break
	}
	filename = contentItem
	return filename?
	.replacingCharacters(in: range, with: "")
	.replacingOccurrences(of: "\"", with: "")
	.trimmingCharacters(in: .whitespacesAndNewlines)
	}

And to generate the sample projects, please run and commit the changes.

./mvnw clean package 
./bin/generate-samples.sh bin/configs/swift5-*

Thanks

[gretzki]

@4brunu sure. Done and done.
I realised it's also a bug for the swift4 client codegen but didn't fix it, since it's not relevant for the above mentioned client swift5. If you think it should be handled here too, I'm happy to fix that part too.

[4brunu]

Swift4 client is now deprecated, so I'm not sure if it's worth the effort.
I think for now I prefer to focus on the Swift5 client, unless there is still demand for the Swift4 client.

[4brunu]

CI is failing, but it's not related to this PR.
Looks good to me this PR 🙂