vweb #

This is pre-alpha software.


  • Very fast: performance of C on the web.
  • Small binary: hello world website is <100 KB.
  • Easy to deploy: just one binary file that also includes all templates. No need to install any dependencies.
  • Templates are precompiled, all errors are visible at compilation time, not at runtime.

Lots of things are broken and not implemented yet in V and vweb.

There's no documentation yet, have a look at a simple example:


There's also the V forum: https://github.com/vlang/vorum

vorum.v contains all GET and POST actions.

pub fn (app mut App) index() {
    posts := app.find_all_posts()

// TODO ['/post/:id/:title']
// TODO `fn (app App) post(id int)`
pub fn (app App) post() {
    id := app.get_post_id()
    post := app.retrieve_post(id) or {
    comments := app.find_comments(id)
    show_form := true

index.html is an example of the V template language:

@for post in posts
    <div class=post>
        <a class=topic href="@post.url">@post.title</a>
        <img class=comment-img>
        <span class=nr-comments>@post.nr_comments</span>
        <span class=time>@post.time</span>

$vweb.html() compiles an HTML template into V during compilation, and embeds the resulting code in current action.

That means that the template automatically has access to that action's entire environment.

Deploying vweb apps

Everything, including HTML templates, is in one binary file. That's all you need to deploy.

Getting Started

To start with vweb, you have to import the module vweb. After the import, define a struct to hold vweb.Context (and any other variables your program will need). The web server can be started by calling vweb.run<App>(port).


import vweb

struct App {

fn main() {

Defining endpoints

To add endpoints to your web server, you have to extend the App struct. For routing you can either use auto-mapping of function names or specify the path as an attribute. The function expects a response of the type vweb.Result.


// This endpoint can be accessed via http://localhost:port/hello
fn (mut app App) hello() vweb.Result {
    return app.text('Hello')

// This endpoint can be accessed via http://localhost:port/foo
fn (mut app App) world() vweb.Result {
    return app.text('World')

To create an HTTP POST endpoint, you simply add a [post] attribute before the function definition.


fn (mut app App) world() vweb.Result {
    return app.text('World')

To pass a parameter to an endpoint, you simply define it inside an attribute, e. g. ['/hello/:user]. After it is defined in the attribute, you have to add it as a function parameter.


fn (mut app App) hello_user(user string) vweb.Result {
    return app.text('Hello $user')

You have access to the raw request data such as headers or the request body by accessing app (which is vweb.Context). If you want to read the request body, you can do that by calling app.req.data. To read the request headers, you just call app.req.header and access the header you want, e.g. app.req.header.get(.content_type). See struct Header for all available methods (v doc net.http Header).

Constants #

const (
	methods_with_form       = [http.Method.post, .put, .patch]
	header_server           = 'Server: VWeb\r\n'
	header_connection_close = 'Connection: close\r\n'
	headers_close           =''$2header_server$header_connection_close\r\n'

	http_400                = 'HTTP/1.1 400 Bad Request\r\nContent-Type: text/plain\r\nContent-Length: 15\r\n${headers_close}400 Bad Request'
	http_404                = 'HTTP/1.1 404 Not Found\r\nContent-Type: text/plain\r\nContent-Length: 13\r\n${headers_close}404 Not Found'
	http_500                = 'HTTP/1.1 500 Internal Server Error\r\nContent-Type: text/plain\r\n${headers_close}500 Internal Server Error'
	mime_types              = map{
		'.css':  'text/css; charset=utf-8'
		'.gif':  'image/gif'
		'.htm':  'text/html; charset=utf-8'
		'.html': 'text/html; charset=utf-8'
		'.jpg':  'image/jpeg'
		'.js':   'application/javascript'
		'.json': 'application/json'
		'.md':   'text/markdown; charset=utf-8'
		'.pdf':  'application/pdf'
		'.png':  'image/png'
		'.svg':  'image/svg+xml'
		'.txt':  'text/plain; charset=utf-8'
		'.wasm': 'application/wasm'
		'.xml':  'text/xml; charset=utf-8'
	max_http_post_size      = 1024 * 1024
	default_port            = 8080

fn not_found #

fn not_found() Result

Returns an empty result

fn run #

fn run<T>(port int)

fn run_app #

fn run_app<T>(mut app T, port int)

type RawHtml #

type RawHtml = string

A type which don't get filtered inside templates

struct Context #

struct Context {
	content_type string = 'text/plain'
	status       string = '200 OK'
	req http.Request
pub mut:
	conn              &net.TcpConn
	static_files      map[string]string
	static_mime_types map[string]string
	form              map[string]string
	query             map[string]string
	files             map[string][]FileData
	headers           string
	done              bool
	page_gen_start    i64
	form_error        string
	chunked_transfer  bool
	max_chunk_len     int = 20

fn (Context) init_once #

fn (ctx Context) init_once()

declaring init_once in your App struct is optional

fn (Context) init #

fn (ctx Context) init()

declaring init in your App struct is optional

fn (Context) send_response_to_client #

fn (mut ctx Context) send_response_to_client(mimetype string, res string) bool

vweb intern function

fn (Context) html #

fn (mut ctx Context) html(s string) Result

Response HTTP_OK with s as payload with content-type text/html

fn (Context) text #

fn (mut ctx Context) text(s string) Result

Response HTTP_OK with s as payload with content-type text/plain

fn (Context) json #

fn (mut ctx Context) json(s string) Result

Response HTTP_OK with s as payload with content-type application/json

fn (Context) ok #

fn (mut ctx Context) ok(s string) Result

Response HTTP_OK with s as payload

fn (Context) server_error #

fn (mut ctx Context) server_error(ecode int) Result

Response a server error

fn (Context) redirect #

fn (mut ctx Context) redirect(url string) Result

Redirect to an url

fn (Context) not_found #

fn (mut ctx Context) not_found() Result

Send an not_found response

fn (Context) enable_chunked_transfer #

fn (mut ctx Context) enable_chunked_transfer(max_chunk_len int)

Enables chunk transfer with max_chunk_len per chunk

fn (Context) set_content_type #

fn (mut ctx Context) set_content_type(typ string)

Sets the response content type

fn (Context) set_status #

fn (mut ctx Context) set_status(code int, desc string)

Sets the response status

fn (Context) add_header #

fn (mut ctx Context) add_header(key string, val string)

Adds an header to the response with key and val

fn (Context) get_header #

fn (ctx &Context) get_header(key string) string

Returns the header data from the key

fn (Context) handle_static #

fn (mut ctx Context) handle_static(directory_path string, root bool) bool

Handles a directory static If root is set the mount path for the dir will be in '/'

fn (Context) mount_static_folder_at #

fn (mut ctx Context) mount_static_folder_at(directory_path string, mount_path string) bool

mount_static_folder_at - makes all static files in directory_path and inside it, available at http://server/mount_path For example: suppose you have called .mount_static_folder_at('/var/share/myassets', '/assets'), and you have a file /var/share/myassets/main.css . => That file will be available at URL: http://server/assets/main.css .

fn (Context) serve_static #

fn (mut ctx Context) serve_static(url string, file_path string, mime_type string)

Serves a file static url is the access path on the site, file_path is the real path to the file, mime_type is the file type

fn (Context) ip #

fn (ctx &Context) ip() string

Returns the ip address from the current user

fn (Context) error #

fn (mut ctx Context) error(s string)

Set s to the form error

struct Result #

struct Result {