cowboy/examples/markdown_middleware/src/markdown_converter.erl

%% Feel free to use, reuse and abuse the code in this file.

-module(markdown_converter).
-behaviour(cowboy_middleware).

-export([execute/2]).

execute(Req, Env) ->
	[Path] = cowboy_req:path_info(Req),
	case filename:extension(Path) of
		<<".html">> -> maybe_generate_markdown(resource_path(Path));
		_Ext -> ok
	end,
	{ok, Req, Env}.

maybe_generate_markdown(Path) ->
	ModifiedAt = filelib:last_modified(source_path(Path)),
	GeneratedAt = filelib:last_modified(Path),
	case ModifiedAt > GeneratedAt of
		true -> markdown:conv_file(source_path(Path), Path);
		false -> ok
	end.

resource_path(Path) ->
	PrivDir = code:priv_dir(markdown_middleware),
	filename:join([PrivDir, Path]).

source_path(Path) ->
	<< (filename:rootname(Path))/binary, ".md" >>.
Add an example with custom middleware 2013-02-09 04:04:49 -06:00			`%% Feel free to use, reuse and abuse the code in this file.`

			`-module(markdown_converter).`
			`-behaviour(cowboy_middleware).`

			`-export([execute/2]).`

			`execute(Req, Env) ->`
Breaking update of the cowboy_req interface Simplify the interface for most cowboy_req functions. They all return a single value except the four body reading functions. The reply functions now only return a Req value. Access functions do not return a Req anymore. Functions that used to cache results do not have a cache anymore. The interface for accessing query string and cookies has therefore been changed. There are now three query string functions: qs/1 provides access to the raw query string value; parse_qs/1 returns the query string as a list of key/values; match_qs/2 returns a map containing the values requested in the second argument, after applying constraints and default value. Similarly, there are two cookie functions: parse_cookies/1 and match_cookies/2. More match functions will be added in future commits. None of the functions return an error tuple anymore. It either works or crashes. Cowboy will attempt to provide an appropriate status code in the response of crashed handlers. As a result, the content decode function has its return value changed to a simple binary, and the body reading functions only return on success. 2014-09-23 16:43:29 +03:00			`[Path] = cowboy_req:path_info(Req),`
Add an example with custom middleware 2013-02-09 04:04:49 -06:00			`case filename:extension(Path) of`
			`<<".html">> -> maybe_generate_markdown(resource_path(Path));`
			`_Ext -> ok`
			`end,`
Breaking update of the cowboy_req interface Simplify the interface for most cowboy_req functions. They all return a single value except the four body reading functions. The reply functions now only return a Req value. Access functions do not return a Req anymore. Functions that used to cache results do not have a cache anymore. The interface for accessing query string and cookies has therefore been changed. There are now three query string functions: qs/1 provides access to the raw query string value; parse_qs/1 returns the query string as a list of key/values; match_qs/2 returns a map containing the values requested in the second argument, after applying constraints and default value. Similarly, there are two cookie functions: parse_cookies/1 and match_cookies/2. More match functions will be added in future commits. None of the functions return an error tuple anymore. It either works or crashes. Cowboy will attempt to provide an appropriate status code in the response of crashed handlers. As a result, the content decode function has its return value changed to a simple binary, and the body reading functions only return on success. 2014-09-23 16:43:29 +03:00			`{ok, Req, Env}.`
Add an example with custom middleware 2013-02-09 04:04:49 -06:00
			`maybe_generate_markdown(Path) ->`
			`ModifiedAt = filelib:last_modified(source_path(Path)),`
			`GeneratedAt = filelib:last_modified(Path),`
			`case ModifiedAt > GeneratedAt of`
Fix markdown example for OTP-27 2024-11-07 13:28:26 +01:00			`true -> markdown:conv_file(source_path(Path), Path);`
Add an example with custom middleware 2013-02-09 04:04:49 -06:00			`false -> ok`
			`end.`

			`resource_path(Path) ->`
Convert the markdown_middleware example to a release 2013-10-22 09:10:24 +02:00			`PrivDir = code:priv_dir(markdown_middleware),`
			`filename:join([PrivDir, Path]).`
Add an example with custom middleware 2013-02-09 04:04:49 -06:00
			`source_path(Path) ->`
			`<< (filename:rootname(Path))/binary, ".md" >>.`