appc/spec

spec: support HTTP headers for discovery

Open

#7 opened on Dec 9, 2014

View on GitHub
 (8 comments) (0 reactions) (0 assignees)Go (143 forks)github user discovery
area/speccomponent/discoveryhelp wanted

Repository metrics

Stars
 (1,253 stars)
PR merge metrics
 (No merged PRs in 30d)

Description

From @bacongobbler on December 4, 2014 17:36

I was sifting through the app-container spec on image discovery when I stumbled across this:

If simple discovery fails, then we use HTTPS+HTML meta tags to resolve an app name to a downloadable URL.

This works for the general use case, but some URLs may not have a content type of text/html e.g. in the case of an API.

For example, if I had a SaaS product and I wanted to have a discoverable URL to our API's ACI, I'd like a URL like https://example.com/api. The top-level domain (https://example.com/) would be our landing page (implying text/html), but https://example.com/api may be where our SaaS's API begins (in this case, application/json or some equivalent).

Would it be possible to extend the image discovery to use HTTP headers (HTTP_X_AC_DISCOVERY?) in the case that the content-type is not text/html? Is there a way to work around this, or would a PR for this type of extension be appreciated? :)

Copied from original issue: coreos/rocket#210

Contributor guide

Research direction
Review the current image discovery spec (SPEC.md) to understand the simple and meta based discovery flows. Then design an extension that checks HTTP response headers (e.g., X AC Discovery) for a downloadable URL when the content type is not text/html. Examine existing reference implementations (e.g., in rkt) for guidance.
Tech stack
go
Domain
backend
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
Git
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
75