This introduces the "additional_headers", "remote_user_header" and
"skip_x_access_token" config keys to allow configuring routes to
external services that require addtional headers to be set.
"remote_user_header": defines the name of a Header that will carry the
userid of the authenticated user on the outgoing request.
"additional_headers": defines a list of header names and values that will
be added to outgoing requests on matching routes.
"skip_x_access_token": when set to true the reva access token will not
be added to the outgoing request.
Needed for #206
This gets us a rid of the need to configure the reva jwt secret in the
proxy. Also we no longer need to fake an internal admin user for
autoprovsioning user and/or assigning the roles to users from oidc
claims.
We were using stretchr/testify and test-go/testify inconsitently and
sometimes mixed in the same tests. This can cause very strange issue,
e.g when using things like mock.MatchedBy().
This moves all our code to stretchr/testify, which seems to be far
more active and maintained then test-go/testify.
This moves the lookup and the creation of the users' role assignemt out
of the user backend into its own interface. This makes the user backend
a bit simpler and allows to provide different implemenation for the user
role assignment more easily.
This removes the "withRoles" flag from the GetUserByClaims lookup and move the
functionality into a separate method. This should make the code a bit more readable
in preparation for maintaining the RoleAssignments from OIDC claims.
