Deprecate buildpack (#243)

* Deprecate buildpack

This build pack is currently not maintained by a team and carries no support obligations. Let's make this clearer by deprecating the build pack.

This is done right before the release of heroku-22 as supporting new stacks require maintenance effort. Also before the desire to re-write it as a CNB comes into play.

* Bring back Readme contents

Having README docs makes it easier for developers to lookup features while they transition off the buildpack.

* Update docs for deprecation

- Mention the need to re-write mruby parts
- Link to a specific nginx build pack and give commands on how to add it
- Give specific command to remove this buildpack from app
- Mention in README we're open to extra docs/help for people migrating off.
- Space after testing header because it's my thing and I looked at those docs. 
- Added a link to where  `Nginx::Request` is defined because it's not obvious it comes from ngx_mruby

* Update README.md

Co-authored-by: Ed Morley <501702+edmorley@users.noreply.github.com>

* Update bin/compile

Co-authored-by: Ed Morley <501702+edmorley@users.noreply.github.com>

* Address PR comments

Co-authored-by: Ed Morley <501702+edmorley@users.noreply.github.com>

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+* [#243](https://github.com/heroku/heroku-buildpack-static/pull/243) Buildpack is officially deprecated
+
 ## v8 (2022-05-19)
 
 * [#240](https://github.com/heroku/heroku-buildpack-static/pull/240) Update ngx_mruby from 2.2.3 to 2.2.4.

README.md

@@ -1,10 +1,35 @@
 # heroku-buildpack-static
+
 **NOTE**: This buildpack is in an experimental OSS project.
 
 This is a buildpack for handling static sites and single page web apps.
 
 For a guide, read the [Getting Started with Single Page Apps on Heroku](https://gist.github.com/hone/24b06869b4c1eca701f9).
 
+## WARNING: `heroku-buildpack-static` is deprecated
+
+This buildpack is deprecated and is no longer being maintained.
+If you are using this project, you can transition over to NGINX via an NGINX buildpack.
+Use your project's existing configuration.
+To find the NGINX configuration generated by the heroku-buildpack-static you can run:
+
+```
+$ heroku run bash
+~ $ bin/config/make-config
+~ $ cat config/nginx.conf
+```
+
+These commands will output your current NGINX config generated from your `static.json` contents.
+
+- Write these contents to your local repo at `config/nginx.conf.erb`, commit them to git.
+- Replace path logic that previously used `mruby` with static logic.
+- Configure your app to use the NGINX buildpack via `heroku buildpacks:add heroku-community/nginx`.
+- Remove this buildpack via `heroku buildpacks:remove heroku-community/static` (or `heroku buildpacks:remove https://github.com/heroku/heroku-buildpack-static`).
+
+## Deprecation PRs
+
+If you have tips or tricks for migrating off of this buildpack and want to add them to the instructions above please send a PR.
+
 ## Features
 * serving static assets
 * gzip on by default
@@ -278,6 +303,7 @@ when accessing `/foo`, `X-Foo` will have the value `"foo"` and `X-Bar` will not
 In case you have multiple buildpacks for the application you can ensure static rendering in `Procfile` with `web: bin/boot`.
 
 ## Testing
+
 For testing we use Docker to replicate Heroku locally. You'll need to have [it setup locally](https://docs.docker.com/installation/). We're also using rspec for testing with Ruby. You'll need to have those setup and install those deps:
 
 ```sh

bin/compile

@@ -8,6 +8,29 @@ cache_dir=$2
 env_dir=$3
 bp_dir=$(dirname $(dirname $0))
 
+cat <<'EOF'
+       ## WARNING: `heroku-buildpack-static` is deprecated
+
+       This buildpack is deprecated and is no longer being maintained.
+       If you are using this project, you can transition over to NGINX via an NGINX buildpack.
+       Use your project's existing configuration.
+       To find the NGINX configuration generated by the heroku-buildpack-static you can run:
+
+       ```
+       $ heroku run bash
+       ~ $ bin/config/make-config
+       ~ $ cat config/nginx.conf
+       ```
+
+       These commands will output your current NGINX config generated from your `static.json` contents.
+
+       - Write these contents to your local repo at `config/nginx.conf.erb`, commit them to git.
+       - Replace path logic that previously used `mruby` with static logic.
+       - Configure your app to use the NGINX buildpack via `heroku buildpacks:add heroku-community/nginx`.
+       - Remove this buildpack via `heroku buildpacks:remove heroku-community/static` (or `heroku buildpacks:remove https://github.com/heroku/heroku-buildpack-static`).
+
+EOF
+
 case "${STACK}" in
   heroku-18|heroku-20)
     nginx_archive_url="https://heroku-buildpack-static.s3.amazonaws.com/${STACK}/nginx-1.21.3-ngx_mruby-2.2.4.tgz"

scripts/config/lib/ngx_mruby/routes_path.rb

@@ -5,7 +5,7 @@
 
 config      = {}
 config      = JSON.parse(File.read(USER_CONFIG)) if File.exist?(USER_CONFIG)
-req         = Nginx::Request.new
+req         = Nginx::Request.new # defined by https://github.com/matsumotory/ngx_mruby/blob/c7682cfb4c0984a41f1a447b71ae01e1f4fcc6bf/docs/class_and_method/README.md#nginxrequest-class
 uri         = req.var.uri
 nginx_route = req.var.route
 routes      = NginxConfigUtil.parse_routes(config["routes"])