142 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			Markdown
		
	
	
			
		
		
	
	
			142 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			Markdown
		
	
	
# vweb - the V Web Server #
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A simple yet powerful web server with built-in routing, parameter handling,
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templating, and other features.
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## Alpha level software ##
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Some features may not be complete, and there may still be bugs.  However, it is
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still a very useful tool.  The [gitly](https://gitly.org/) site is based on vweb.
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## Features ##
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- **Very fast** performance of C on the web.
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- **Small binary** hello world website is <100 KB.
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- **Easy to deploy** just one binary file that also includes all templates.
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  No need to install any dependencies.
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- **Templates are precompiled** all errors are visible at compilation time,
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  not at runtime.
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There is no formal documentation yet - here is a simple
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[example](https://github.com/vlang/v/tree/master/examples/vweb/vweb_example.v)
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There's also the V forum, [vorum](https://github.com/vlang/vorum)
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`vorum.v` contains all GET and POST actions.
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```v ignore
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pub fn (app mut App) index() {
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	posts := app.find_all_posts()
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	$vweb.html()
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}
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// TODO ['/post/:id/:title']
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// TODO `fn (app App) post(id int)`
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pub fn (app App) post() {
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	id := app.get_post_id()
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	post := app.retrieve_post(id) or {
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		app.redirect('/')
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		return
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	}
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	comments := app.find_comments(id)
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	show_form := true
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	$vweb.html()
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}
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```
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`index.html` is an example of the V template language:
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```html
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@for post in posts
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	<div class=post>
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		<a class=topic href="@post.url">@post.title</a>
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		<img class=comment-img>
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		<span class=nr-comments>@post.nr_comments</span>
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		<span class=time>@post.time</span>
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	</div>
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@end
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```
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`$vweb.html()` compiles an HTML template into V during compilation,
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and embeds the resulting code into the current action.
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That means that the template automatically has access to that action's entire environment.
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## Deploying vweb apps ##
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Everything, including HTML templates, is in one binary file. That's all you need to deploy.
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## Getting Started ##
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To start with vweb, you have to import the module `vweb`.  After the import,
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define a struct to hold vweb.Context (and any other variables your program will
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need).
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The web server can be started by calling `vweb.run(&App{}, port)`.
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**Example:**
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```v ignore
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import vweb
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struct App {
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    vweb.Context
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}
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fn main() {
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	vweb.run(&App{}, 8080)
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}
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```
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### Defining endpoints ###
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To add endpoints to your web server, you have to extend the `App` struct.
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For routing you can either use auto-mapping of function names or specify the path as an attribute.
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The function expects a response of the type `vweb.Result`.
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**Example:**
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```v ignore
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// This endpoint can be accessed via http://localhost:port/hello
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fn (mut app App) hello() vweb.Result {
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	return app.text('Hello')
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}
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// This endpoint can be accessed via http://localhost:port/foo
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["/foo"]
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fn (mut app App) world() vweb.Result {
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	return app.text('World')
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}
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```
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To create an HTTP POST endpoint, you simply add a `[post]` attribute before the function definition.
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**Example:**
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```v ignore
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[post]
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fn (mut app App) world() vweb.Result {
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	return app.text('World')
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}
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```
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To pass a parameter to an endpoint, you simply define it inside
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an attribute, e. g. `['/hello/:user]`.
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After it is defined in the attribute, you have to add it as a function parameter.
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**Example:**
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```v ignore
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['/hello/:user']
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fn (mut app App) hello_user(user string) vweb.Result {
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	return app.text('Hello $user')
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}
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```
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You have access to the raw request data such as headers
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or the request body by accessing `app` (which is `vweb.Context`).
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If you want to read the request body, you can do that by calling `app.req.data`.
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To read the request headers, you just call `app.req.header` and access the
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header you want, e.g. `app.req.header.get(.content_type)`. See `struct Header`
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for all available methods (`v doc net.http Header`).
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