Add account uuid extraction middleware

[kulmann]

Adds a middleware for extracting the account uuid from the x-access-token header and providing it in the context. This can be used in any ocis service that needs the account uuid. It is minted into the x-access-token by the proxy.

There are version incompatibilities that need to be solved... thus creating this as a draft.

[update-docs]

Thanks for opening this pull request! The maintainers of this repository would appreciate it if you would create a changelog item based on your changes.

[refs]

The only piece of feedback I have is that we're tying our data model to Reva here for all consumers of this context. Should we instead deal with the UUID, and not missleadingly store an opaque id under a UUIDKey?

[kulmann]

The opaque id is what we previously set in the proxy and is in fact our UUID. Maybe a good idea to have the proxy middleware about the account uuid here in ocis-pkg as well, to make it more transparent what we're doing.

[ownclouders]

Here is an overview of what got changed by this pull request:

Complexity increasing per file
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- account/option.go  1
- middleware/account.go  4
         

See the complete overview on Codacy