7.7 KiB
zerve
A simple framework for writing web services in zig.
Create a simple web app
const zrv = @import("zerve"); // Or set the path to zerve.zig e.g. @import("zerve-main/src/zerve.zig");
const Request = zrv.Request;
const Response = zrv.Response;
const Server = zrv.Server;
const Route = zrv.Route;
const allocator = std.heap.page_allocator; // Choose any allocator you want!
fn index(req: *Request) Response {
_=req;
return Response.write("hello!");
}
fn about(req: *Request) Response {
_=req;
return Response.write("about site");
}
fn writeJson(req: *Request) Response {
_=req;
return Response.json("[1, 2, 3, 4]");
}
pub fn main() !void {
const rt = [_]Route{.{"/", index}, .{"/about", about}, .{"/json", writeJson}};
try Server.listen("0.0.0.0", 8080, &rt, allocator); // listens to http://localhost:8080
// http://localhost:8080/ "hello!"
// http://localhost:8080/about "about site"
// http://localhost:8080/json "[1, 2, 3, 4]" (JSON-Response)
}
Types
Route
To write a web service with zerve you have to configure one or more Routes. They are being set by creating an Array of Route.
Example:
const rt = [_]Route{.{"/hello", helloFunction}, "/about", aboutFunction};
You can also set only one path and link it to a handler function, but since Server.listen() takes an Array of Route as one of it's arguments,
you have do declare it as an Array as well:
const rt = [_]Route{.{"/hello", helloFunction}};
Handler Functions
Every Request is handled by a handler function. It has to be of this type: fn(req: *Request) Response
Example:
fn hello(req: *Request) Response {
_ = req;
return Response.write("hello"); // `Server` will return a Reponse with body "hello". You will see "hello" on your browser.
}
Request
This represents the Request sent by the client.
pub const Request = struct {
/// The Request Method, e.g. "GET"
method: Method,
/// HTTP-Version of the Request sent by the client
httpVersion: HTTP_Version,
/// Represents the request headers sent by the client
headers: []const Header,
/// The Request URI
uri: []const u8,
/// Represents the request body sent by the client
body: []const u8,
};
Get Query Params
zerve lets you easily extract query params no matter if Requestmethod is GETor POST.
This can be done by using the getQuery method of Request.
Example:
fn index(req: Request) Response {
// Assuming that a query string has been sent by the client containing the requested param,
// e.g. `?user=james`
const user = req.getQuery("user"); // This will return an optional
if (user == null) return Response.write("") else return Response.write(user.?);
}
Get value of Request header by key
You can get the header value of any sent header by the client with the headermethod of Request.
Example:
fn index(req: *Request) Response {
// Get value of the 'Content-Type' header
const h = req.header("Content-Type"); // This will return an optional
if (h == null) return Response.write("Header not found!") else return Response.write(h.?);
}
Response
A Response that is sent ny the server. Every handler function has to return a Response.
pub const Response = struct {
httpVersion: HTTP_Version = HTTP_Version.HTTP1_1,
/// Response status, default is "200 OK"
status: stat.Status = stat.Status.OK,
/// Response eaders sent by the server
headers: []const Header = &[_]Header{.{ .key = "Content-Type", .value = "text/html; charset=utf-8" }},
/// Response body sent by the server
body: []const u8 = "",
/// Write a simple response.
pub fn write(s: []const u8) Response
/// Send a response with json content.
pub fn json(j: []const u8) Response
/// Send a response with status not found.
pub fn notfound(s: []const u8) Response
/// Send a response with status forbidden.
pub fn forbidden(s: []u8) Response
};
Header
Every Request or Response has Headers represented by an Array of Headers. Every Header has a key and a value.
pub const Header = struct {
key: []const u8,
value: []const u8,
};
Cookies
Read Cookie from Request
To read the Cookie of a request by key, Request has a cookie-method.
It returns an optional and fetches the value of a Request.Cookie.
Get Request Cookie value by key:
fn index(req: *Request) Response {
// Fetches the cookie value by cookie name.
// The `cookie` method will return an optional and will be `null`
// in case that the cookie does not exist.
const cookie = if (req.cookie("password")) |password| password else "";
return Response.write("cookie-test");
}
Add Cookie to Response
To send a cookie in your Response just add a Response.Cookie to the cookies field.
The cookies field is a slice of Response.Cookie.
fn index(_: *Request) Response {
// Define a cookie with name and value.
// It will live for 24 hours, since `maxAge` represents
// lifetime in seconds.
// See all field of the `Response.Cookie` struct below.
const cookie = Response.Cookie{.name="User", .value="James", .maxAge=60*60*24};
var res = Response.write("Set Cookie!");
// add cookie to the `cookies` field which is a slice of `Response.Cookie`
res.cookies = &[_]Response.Cookie{.{cookie}};
return res;
}
This are the fields of Response.Cookie:
name: []const u8,
value: []const u8,
path: []const u8 = "/",
domain: []const u8 = "",
/// Indicates the number of seconds until the cookie expires.
maxAge: i64 = 0,
secure: bool = true,
httpOnly: bool = true,
sameSite: SameSite = .lax,
Method
Represents the http method of a Request or a Response.
pub const Method = enum {
GET,
POST,
PUT,
HEAD,
DELETE,
CONNECT,
OPTIONS,
TRACE,
PATCH,
UNKNOWN,
/// Turns the HTTP_method into a u8-Slice.
pub fn stringify(m: Method) []const u8 {...}
};
HTTP-Version
The HTTP-Version of a Request or a Response.
pub const HTTP_Version = enum {
HTTP1_1,
HTTP2,
/// Parses from `[]u8`
pub fn parse(s: []const u8) HTTP_Version {...}
/// Stringifies `HTTP_Version`
pub fn stringify(version: HTTP_Version) []const u8 {...}
};
Namespaces
Server
Server is a namespace to configure IP and Port the app will listen to by calling Server.listen(), as well as the routing paths ([]Route) it shall handle.
You can also choose an allocator that the app will use for dynamic memory allocation.
pub fn listen(ip: []const u8, port: u16, rt: []const Route, allocator: std.mem.Allocator) !void {...}