How to use

First, import Jwt on your Zig source file.

const jwt = @import("jwt");

Now, add the following code into your main function.

var gpa_mem = std.heap.DebugAllocator(.{}).init;
defer std.debug.assert(gpa_mem.deinit() == .ok);
const heap = gpa_mem.allocator();

Encode a JWT Token

Here, Userdata is a custom struct that holds application-specific authentication details.

const Userdata = struct {
    role: []const u8,
    feature: []const []const u8
};

const key = "secret";

const token = try jwt.Jws(Userdata).encode(heap, key, .{
    .sub = "john",
    .iss = "example.com",
    .aud = "hydra",
    .data = .{
        .role = "admin",
        .feature = &.{"foo", "bar"}
    },
    .iat = jwt.setTime(.Second, 0),
    .nbf = jwt.setTime(.Second, 0),
    .exp = jwt.setTime(.Minute, 2),
});
defer heap.free(token);

std.debug.print("JWT Token: {s}", .{token});

Decode a JWT Token

Token validation is handled internally, which automatically verifies the signature, checks required claims such as exp (expiration), nbf (not before), and ensures the token is structurally valid and not tampered with.

const token = "your jwt token...";

const claims = try jwt.Jws(Userdata).decode(heap, key, token);
std.debug.print("{any}\n", .{claims});
try jwt.free(heap, claims);