JSON

api.zig includes JSON utilities for parsing and serialization.

JSON Methods

Method	Description
json.parse(T, allocator, str)	Parse JSON string to struct
json.parseValue(allocator, str)	Parse to dynamic value
json.stringify(allocator, value, opts)	Serialize to JSON string
json.toPrettyJson(allocator, value)	Serialize with formatting
json.isValid(str)	Check if string is valid JSON
json.escapeString(allocator, str)	Escape special characters

Parsing JSON

Parse into Type

const json = api.json;

const User = struct {
    id: u32,
    name: []const u8,
    active: bool,
};

const json_str = "{\"id\":1,\"name\":\"John\",\"active\":true}";
const user = try json.parse(User, allocator, json_str);

// user.id = 1
// user.name = "John"
// user.active = true

Input:

{"id":1,"name":"John","active":true}

Result: User{ .id = 1, .name = "John", .active = true }

Parse Dynamic JSON

const parsed = try json.parseValue(allocator, json_str);
defer parsed.deinit();

// Access values
const id = parsed.value.object.get("id").?.integer;

Serializing to JSON

Stringify

const user = User{
    .id = 1,
    .name = "John",
    .active = true,
};

const json_str = try json.stringify(allocator, user, .{});
defer allocator.free(json_str);
// {"id":1,"name":"John","active":true}

Pretty Print

const json_str = try json.toPrettyJson(allocator, user);
defer allocator.free(json_str);
// {
//   "id": 1,
//   "name": "John",
//   "active": true
// }

Validation

Check Valid JSON

if (json.isValid("{\"valid\":true}")) {
    // Valid JSON
}

if (!json.isValid("{invalid")) {
    // Invalid JSON
}

Escaping Strings

const escaped = try json.escapeString(allocator, "hello\nworld");
defer allocator.free(escaped);
// hello\\nworld

Handler Example

fn createUser(ctx: *api.Context) api.Response {
    const body = ctx.body();

    // Validate JSON format
    if (!api.json.isValid(body)) {
        return api.Response.err(.bad_request, "{\"error\":\"Invalid JSON\"}");
    }

    // Process the request...
    return api.Response.jsonRaw("{\"created\":true}")
        .setStatus(.created);
}

JSON Response Helpers

Raw JSON String

// For pre-formatted JSON strings
api.Response.jsonRaw("{\"message\":\"Hello\"}")

Building JSON Manually

fn handler(ctx: *api.Context) api.Response {
    _ = ctx;

    // For simple responses, use raw JSON
    return api.Response.jsonRaw("{\"status\":\"ok\",\"timestamp\":1234567890}");
}

Error Handling

fn parseBody(ctx: *api.Context) api.Response {
    const body = ctx.body();

    const User = struct { name: []const u8 };

    const user = api.json.parse(User, ctx.allocator, body) catch {
        return api.Response.err(.bad_request, "{\"error\":\"Invalid JSON body\"}");
    };

    _ = user;
    return api.Response.jsonRaw("{\"ok\":true}");
}