Since the repo is no longer just the registry, we are moving the registry web
application package out of the repo root into a sub-package. We may break down
the registry package further to separate webapp components and bring the client
package under it. This change accomplishes the task of freeing up the repo root
for a distribution-oriented package. A stub doc.go file is left in place to
declare intent.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
This changeset defines the application structure to be used for the http side
of the new registry. The main components are the App and Context structs. The
App context is instance global and manages global configuration and resources.
Context contains request-specific resources that may be created as a by-product
of an in-flight request.
To latently construct per-request handlers and leverage gorilla/mux, a dispatch
structure has been propped up next to the main handler flow. Without this, a
router and all handlers need to be constructed on every request. By
constructing handlers on each request, we ensure thread isolation and can
carefully control the security context of in-flight requests. There are unit
tests covering this functionality.