From 078d686a0ac0aed212db97d73bd1e4a9387a4956 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Lo=C3=AFc=20Hoguin?= Date: Sun, 6 Jul 2014 13:10:35 +0200 Subject: Provide installable man pages make docs: generate Markdown and man pages in doc/ make install-docs: install man pages to be usable directly Docs are generated from the ezdoc files in doc/src/. --- guide/static_handlers.md | 172 ----------------------------------------------- 1 file changed, 172 deletions(-) delete mode 100644 guide/static_handlers.md (limited to 'guide/static_handlers.md') diff --git a/guide/static_handlers.md b/guide/static_handlers.md deleted file mode 100644 index 4e0bcfc..0000000 --- a/guide/static_handlers.md +++ /dev/null @@ -1,172 +0,0 @@ -Static handler -============== - -The static handler is a built-in REST handler for serving files. -It is available as a convenience and provides a quick solution -for serving files during development. - -For systems in production, consider using one of the many -Content Distribution Network (CDN) available on the market, -as they are the best solution for serving files. They are -covered in the next chapter. If you decide against using a -CDN solution, then please look at the chapter after that, -as it explains how to efficiently serve static files on -your own. - -The static handler can serve either one file or all files -from a given directory. It can also send etag headers for -client-side caching. - -To use the static file handler, simply add routes for it -with the appropriate options. - -Serve one file --------------- - -You can use the static handler to serve one specific file -from an application's private directory. This is particularly -useful to serve an `index.html` file when the client requests -the `/` path, for example. The path configured is relative -to the given application's private directory. - -The following rule will serve the file `static/index.html` -from the application `my_app`'s priv directory whenever the -path `/` is accessed. - -``` erlang -{"/", cowboy_static, {priv_file, my_app, "static/index.html"}} -``` - -You can also specify the absolute path to a file, or the -path to the file relative to the current directory. - -``` erlang -{"/", cowboy_static, {file, "/var/www/index.html"}} -``` - -Serve all files from a directory --------------------------------- - -You can also use the static handler to serve all files that -can be found in the configured directory. The handler will -use the `path_info` information to resolve the file location, -which means that your route must end with a `[...]` pattern -for it to work. All files are served, including the ones that -may be found in subfolders. - -You can specify the directory relative to an application's -private directory. - -The following rule will serve any file found in the application -`my_app`'s priv directory inside the `static/assets` folder -whenever the requested path begins with `/assets/`. - -``` erlang -{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets"}} -``` - -You can also specify the absolute path to the directory or -set it relative to the current directory. - -``` erlang -{"/assets/[...]", cowboy_static, {dir, "/var/www/assets"}} -``` - -Customize the mimetype detection --------------------------------- - -By default, Cowboy will attempt to recognize the mimetype -of your static files by looking at the extension. - -You can override the function that figures out the mimetype -of the static files. It can be useful when Cowboy is missing -a mimetype you need to handle, or when you want to reduce -the list to make lookups faster. You can also give a -hard-coded mimetype that will be used unconditionally. - -Cowboy comes with two functions built-in. The default -function only handles common file types used when building -Web applications. The other function is an extensive list -of hundreds of mimetypes that should cover almost any need -you may have. You can of course create your own function. - -To use the default function, you should not have to configure -anything, as it is the default. If you insist, though, the -following will do the job. - -``` erlang -{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets", - [{mimetypes, cow_mimetypes, web}]}} -``` - -As you can see, there is an optional field that may contain -a list of less used options, like mimetypes or etag. All option -types have this optional field. - -To use the function that will detect almost any mimetype, -the following configuration will do. - -``` erlang -{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets", - [{mimetypes, cow_mimetypes, all}]}} -``` - -You probably noticed the pattern by now. The configuration -expects a module and a function name, so you can use any -of your own functions instead. - -``` erlang -{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets", - [{mimetypes, Module, Function}]}} -``` - -The function that performs the mimetype detection receives -a single argument that is the path to the file on disk. It -is recommended to return the mimetype in tuple form, although -a binary string is also allowed (but will require extra -processing). If the function can't figure out the mimetype, -then it should return `{<<"application">>, <<"octet-stream">>, []}`. - -When the static handler fails to find the extension in the -list, it will send the file as `application/octet-stream`. -A browser receiving such file will attempt to download it -directly to disk. - -Finally, the mimetype can be hard-coded for all files. -This is especially useful in combination with the `file` -and `priv_file` options as it avoids needless computation. - -``` erlang -{"/", cowboy_static, {priv_file, my_app, "static/index.html", - [{mimetypes, {<<"text">>, <<"html">>, []}}]}} -``` - -Generate an etag ----------------- - -By default, the static handler will generate an etag header -value based on the size and modified time. This solution -can not be applied to all systems though. It would perform -rather poorly over a cluster of nodes, for example, as the -file metadata will vary from server to server, giving a -different etag on each server. - -You can however change the way the etag is calculated. - -``` erlang -{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets", - [{etag, Module, Function}]}} -``` - -This function will receive three arguments: the path to the -file on disk, the size of the file and the last modification -time. In a distributed setup, you would typically use the -file path to retrieve an etag value that is identical across -all your servers. - -You can also completely disable etag handling. - -``` erlang -{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets", - [{etag, false}]}} -``` -- cgit v1.2.3