Linksharing Accept-Encoding parsing needs improvement

[wthorp]

Expected Behavior

Linksharing ZIP support should return compressed content when presented with valid, complex Accept-Encoding strings.

Current Behavior

Linksharing uses simplified Accept-Encoding parsing which does not detect all requests for compressed content.

Possible Solution

Implement more robust Accept-Encoding parsing.

Steps to Reproduce

1. Send request with Accept-encoding header br;q=1.0, gzip;q=0.8, *;q=0.1 when requesting content from a ZIP file

Context (Environment)

Accept-Encoding is a forbidden HTTP header according to the Fetch spec. Thus it can't be precisely set from Javascript, and instead relies on what the browser sends. This breaks Linksharing's ability to send compressed ZIP content to a browser, as browsers tend to deliver more complex strings.

Detailed Description

Use better Accept-Encoding parser logic instead of https://github.com/storj/edge/blob/0c1c0d33f8330aba580729d7851aa44ddbb475ba/pkg/linksharing/sharing/present.go#L214

Possible Implementation

Another nice-to-have here might be a URL parameter or non-forbidden header to fall back on.

[storj-gerrit[bot]]

Change pkg/linksharing/sharing: extend Accept-Encoding parsing for zip content mentions this issue.