fediglam/src/main.zig

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const std = @import("std");
pub const io_mode = .evented;
const Reader = std.net.Stream.Reader;
const Writer = std.net.Stream.Writer;
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const case_insensitive_utf8 = struct {
const Hash = std.hash.Wyhash;
const View = std.unicode.Utf8View;
const toLower = std.ascii.toLower;
const isAscii = std.ascii.isASCII;
const seed = 1;
pub fn hash(str: []const u8) u64 {
// fallback to regular hash on invalid utf8
const view = View.init(str) catch return Hash.hash(seed, str);
var iter = view.iterator();
var h = Hash.init(seed);
var it = iter.nextCodepointSlice();
while (it != null) : (it = iter.nextCodepointSlice()) {
if (it.?.len == 1 and isAscii(it.?[0])) {
const ch = [1]u8{toLower(it.?[0])};
h.update(&ch);
} else {
h.update(it.?);
}
}
return h.final();
}
pub fn eql(a: []const u8, b: []const u8) bool {
if (a.len != b.len) return false;
const va = View.init(a) catch return std.mem.eql(u8, a, b);
const vb = View.init(b) catch return false;
var iter_a = va.iterator();
var iter_b = vb.iterator();
var it_a = iter_a.nextCodepointSlice();
var it_b = iter_b.nextCodepointSlice();
while (it_a != null and it_b != null) : ({
it_a = iter_a.nextCodepointSlice();
it_b = iter_b.nextCodepointSlice();
}) {
if (it_a.?.len != it_b.?.len) return false;
if (it_a.?.len == 1) {
if (isAscii(it_a.?[0]) and isAscii(it_b.?[0])) {
const ch_a = toLower(it_a.?[0]);
const ch_b = toLower(it_b.?[0]);
if (ch_a != ch_b) return false;
} else if (it_a.?[0] != it_b.?[0]) return false;
} else if (!std.mem.eql(u8, it_a.?, it_b.?)) return false;
}
return it_a == null and it_b == null;
}
pub fn lowerInPlace(str: []u8) void {
const view = View.init(str) catch return;
var iter = view.iterator();
var it = iter.nextCodepointSlice();
while (it != null) : (it = iter.nextCodepointSlice()) {
if (isAscii(it.?[0])) it.?[0] = toLower(it.?[0]);
}
}
};
const HeaderMap = std.HashMap([]const u8, []const u8, struct {
pub fn eql(_: @This(), a: []const u8, b: []const u8) bool {
return case_insensitive_utf8.eql(a, b);
}
pub fn hash(_: @This(), str: []const u8) u64 {
return case_insensitive_utf8.hash(str);
}
}, std.hash_map.default_max_load_percentage);
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fn handleBadRequest(writer: Writer) !void {
std.log.info("400 Bad Request", .{});
try writer.writeAll("HTTP/1.1 400 Bad Request");
}
fn handleNotImplemented(writer: Writer) !void {
std.log.info("501", .{});
try writer.writeAll("HTTP/1.1 501 Not Implemented");
}
fn handleInternalError(writer: Writer) !void {
std.log.info("500", .{});
try writer.writeAll("HTTP/1.1 500 Internal Server Error");
}
const Method = enum {
GET,
//HEAD,
POST,
//PUT,
//DELETE,
//CONNECT,
//OPTIONS,
//TRACE,
};
fn parseHttpMethod(reader: Reader) !Method {
var buf: [8]u8 = undefined;
const str = reader.readUntilDelimiter(&buf, ' ') catch |err| switch (err) {
error.StreamTooLong => return error.MethodNotImplemented,
else => return err,
};
inline for (@typeInfo(Method).Enum.fields) |method| {
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if (std.mem.eql(u8, method.name, str)) {
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return @intToEnum(Method, method.value);
}
}
return error.MethodNotImplemented;
}
fn checkProto(reader: Reader) !void {
var buf: [8]u8 = undefined;
const proto = reader.readUntilDelimiter(&buf, '/') catch |err| switch (err) {
error.StreamTooLong => return error.UnknownProtocol,
else => return err,
};
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if (!std.mem.eql(u8, proto, "HTTP")) {
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return error.UnknownProtocol;
}
const count = try reader.read(buf[0..3]);
if (count != 3 or buf[1] != '.') {
return error.BadRequest;
}
if (buf[0] != '1' or buf[2] != '1') {
return error.HttpVersionNotSupported;
}
}
fn extractHeaderName(line: []const u8) ?[]const u8 {
var index: usize = 0;
// TODO: handle whitespace
while (index < line.len) : (index += 1) {
if (line[index] == ':') {
if (index == 0) return null;
return line[0..index];
}
}
return null;
}
fn parseHeaders(allocator: std.mem.Allocator, reader: Reader) !HeaderMap {
var map = HeaderMap.init(allocator);
errdefer map.deinit();
// TODO: free map keys/values
var buf: [1024]u8 = undefined;
while (true) {
const line = try reader.readUntilDelimiter(&buf, '\n');
if (line.len == 0 or (line.len == 1 and line[0] == '\r')) break;
// TODO: handle multi-line headers
const name = extractHeaderName(line) orelse continue;
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const value_end = if (line[line.len - 1] == '\r') line.len - 1 else line.len;
const value = line[name.len + 1 + 1 .. value_end];
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if (name.len == 0 or value.len == 0) return error.BadRequest;
const name_alloc = try allocator.alloc(u8, name.len);
errdefer allocator.free(name_alloc);
const value_alloc = try allocator.alloc(u8, value.len);
errdefer allocator.free(value_alloc);
@memcpy(name_alloc.ptr, name.ptr, name.len);
@memcpy(value_alloc.ptr, value.ptr, value.len);
try map.put(name_alloc, value_alloc);
}
return map;
}
fn handleConnection(conn: std.net.StreamServer.Connection) void {
defer conn.stream.close();
const reader = conn.stream.reader();
const writer = conn.stream.writer();
handleRequest(reader, writer) catch |err| std.log.err("unhandled error processing connection: {}", .{err});
}
fn handleRequest(reader: Reader, writer: Writer) !void {
handleHttpRequest(reader, writer) catch |err| switch (err) {
error.BadRequest, error.UnknownProtocol => try handleBadRequest(writer),
error.MethodNotImplemented, error.HttpVersionNotSupported => try handleNotImplemented(writer),
else => {
std.log.err("unknown error handling request: {}", .{err});
try handleInternalError(writer);
},
};
}
fn handleHttpRequest(reader: Reader, writer: Writer) anyerror!void {
const method = try parseHttpMethod(reader);
var header_buf: [1 << 16]u8 = undefined;
var fba = std.heap.FixedBufferAllocator.init(&header_buf);
const allocator = fba.allocator();
const path = reader.readUntilDelimiterAlloc(allocator, ' ', header_buf.len) catch |err| switch (err) {
error.StreamTooLong => return error.URITooLong,
else => return err,
};
try checkProto(reader);
_ = try reader.readByte();
_ = try reader.readByte();
const headers = try parseHeaders(allocator, reader);
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const has_body = (headers.get("Content-Length") orelse headers.get("Transfer-Encoding")) != null;
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const tfer_encoding = headers.get("Transfer-Encoding");
if (tfer_encoding != null and !std.mem.eql(u8, tfer_encoding.?, "identity")) {
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return error.UnsupportedMediaType;
}
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const encoding = headers.get("Content-Encoding");
if (encoding != null and !std.mem.eql(u8, encoding.?, "identity")) {
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return error.UnsupportedMediaType;
}
var context = Context{
.request = .{
.method = method,
.path = path,
.headers = headers,
.body = if (has_body) reader else null,
},
.response = .{
.headers = HeaderMap.init(allocator),
.writer = writer,
},
.allocator = allocator,
};
try routeRequest(&context);
}
const Context = struct {
const Request = struct {
method: Method,
path: []const u8,
route: ?*const Route = null,
headers: HeaderMap,
body: ?Reader,
pub fn arg(self: *Request, name: []const u8) []const u8 {
return self.route.?.arg(name, self.path);
}
};
const Response = struct {
headers: HeaderMap,
writer: Writer,
fn writeHeaders(self: *Response) !void {
var iter = self.headers.iterator();
var it = iter.next();
while (it != null) : (it = iter.next()) {
try self.writer.print("{s}: {s}\r\n", .{ it.?.key_ptr.*, it.?.value_ptr.* });
}
}
fn statusText(status: u16) []const u8 {
return switch (status) {
200 => "OK",
204 => "No Content",
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404 => "Not Found",
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else => "",
};
}
fn openInternal(self: *Response, status: u16) !void {
try self.writer.print("HTTP/1.1 {} {s}\r\n", .{ status, statusText(status) });
try self.writeHeaders();
try self.writer.writeAll("Connection: close\r\n"); // TODO
}
pub fn open(self: *Response, status: u16) !Writer {
try self.openInternal(status);
try self.writer.writeAll("\r\n");
return self.writer;
}
pub fn write(self: *Response, status: u16, body: []const u8) !void {
try self.openInternal(status);
if (body.len != 0) {
try self.writer.print("Content-Length: {}\r\n", .{body.len});
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if (self.headers.get("Content-Type") == null) {
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try self.writer.writeAll("Content-Type: application/octet-stream\r\n");
}
}
try self.writer.writeAll("\r\n");
if (body.len != 0) {
try self.writer.writeAll(body);
}
}
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pub fn statusOnly(self: *Response, status: u16) !void {
try self.openInternal(status);
}
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};
request: Request,
response: Response,
allocator: std.mem.Allocator,
};
const Route = struct {
const Segment = union(enum) {
param: []const u8,
literal: []const u8,
};
const Handler = fn (*Context) callconv(.Async) anyerror!void;
fn normalize(comptime path: []const u8) []const u8 {
var arr: [path.len]u8 = undefined;
var i = 0;
for (path) |ch| {
if (i == 0 and ch == '/') continue;
if (i > 0 and ch == '/' and arr[i - 1] == '/') continue;
arr[i] = ch;
i += 1;
}
if (i > 0 and arr[i - 1] == '/') {
i -= 1;
}
return arr[0..i];
}
fn parseSegments(comptime path: []const u8) []const Segment {
var count = 1;
for (path) |ch| {
if (ch == '/') count += 1;
}
var segment_array: [count]Segment = undefined;
var segment_start = 0;
for (segment_array) |*seg| {
var index = segment_start;
while (index < path.len) : (index += 1) {
if (path[index] == '/') {
break;
}
}
const slice = path[segment_start..index];
if (slice.len > 0 and slice[0] == ':') {
// doing this kinda jankily to get around segfaults in compiler
const param = path[segment_start + 1 .. index];
seg.* = .{ .param = param };
} else {
seg.* = .{ .literal = slice };
}
segment_start = index + 1;
}
return &segment_array;
}
pub fn from(method: Method, comptime path: []const u8, handler: Handler) Route {
const segments = parseSegments(normalize(path));
return Route{ .method = method, .path = segments, .handler = handler };
}
fn nextSegment(path: []const u8) ?[]const u8 {
var start: usize = 0;
var end: usize = start;
while (end < path.len) : (end += 1) {
// skip leading slash
if (end == start and path[start] == '/') {
start += 1;
continue;
} else if (path[end] == '/') {
break;
}
}
if (start == end) return null;
return path[start..end];
}
pub fn matches(self: Route, path: []const u8) bool {
var segment_start: usize = 0;
for (self.path) |seg| {
var index = segment_start;
while (index < path.len) : (index += 1) {
// skip leading slash
if (index == segment_start and path[index] == '/') {
segment_start += 1;
continue;
} else if (path[index] == '/') {
break;
}
}
const slice = path[segment_start..index];
const match = switch (seg) {
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.literal => |str| case_insensitive_utf8.eql(slice, str),
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.param => true,
};
if (!match) return false;
segment_start = index + 1;
}
// check for trailing path
while (segment_start < path.len) : (segment_start += 1) {
if (path[segment_start] != '/') return false;
}
return true;
}
pub fn arg(self: Route, name: []const u8, path: []const u8) []const u8 {
var index: usize = 0;
for (self.path) |seg| {
const slice = nextSegment(path[index..]);
if (slice == null) return "";
index = @ptrToInt(slice.?.ptr) - @ptrToInt(path.ptr) + slice.?.len + 1;
switch (seg) {
.param => |param| {
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if (std.mem.eql(u8, param, name)) {
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return slice.?;
}
},
.literal => continue,
}
}
std.log.err("unknown parameter {s}", .{name});
return "";
}
method: Method,
path: []const Segment,
handler: Handler,
};
fn handleNotFound(ctx: *Context) !void {
try ctx.response.writer.writeAll("HTTP/1.1 404 Not Found\r\n\r\n");
}
fn routeRequest(ctx: *Context) !void {
for (routes) |*route| {
if (route.method == ctx.request.method and route.matches(ctx.request.path)) {
std.log.info("{s} {s}", .{ @tagName(ctx.request.method), ctx.request.path });
ctx.request.route = route;
var buf = try ctx.allocator.allocWithOptions(u8, @frameSize(route.handler), 8, null);
defer ctx.allocator.free(buf);
return await @asyncCall(buf, {}, route.handler, .{ctx});
}
}
std.log.info("404 {s} {s}", .{ @tagName(ctx.request.method), ctx.request.path });
try handleNotFound(ctx);
}
const routes = [_]Route{
Route.from(.GET, "/", staticString("Index Page")),
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Route.from(.GET, "/abc", staticString("abc")),
Route.from(.GET, "/user/:id", getUser),
};
const this_scheme = "http";
const this_host = "localhost:8080";
const account = .{
.id = "abc123",
.handle = "testacct",
.host = this_host,
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};
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fn getUser(ctx: *Context) anyerror!void {
const id = ctx.request.arg("id");
const host = ctx.request.headers.get("host");
if (host == null) {
try ctx.response.statusOnly(400);
return;
}
if (!std.mem.eql(u8, account.id, id) or
!std.mem.eql(u8, account.host, ctx.request.headers.get("host").?))
{
try ctx.response.statusOnly(404);
return;
}
try ctx.response.headers.put("Content-Type", "application/ld+json; profile=\"https://www.w3.org/ns/activitystreams\"");
var writer = try ctx.response.open(200);
try writer.writeAll("{\"type\":\"Person\",");
try writer.print("\"id\":\"{s}://{s}/user/{s}\",", .{ this_scheme, this_host, id });
try writer.print("\"preferredUsername\":\"{s}\"", .{account.handle});
try writer.writeAll("}");
}
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fn staticString(comptime str: []const u8) Route.Handler {
return (struct {
fn func(ctx: *Context) anyerror!void {
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try ctx.response.headers.put("Content-Type", "text/plain");
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try ctx.response.write(200, str);
}
}).func;
}
pub fn main() anyerror!void {
var srv = std.net.StreamServer.init(.{ .reuse_address = true });
defer srv.deinit();
try srv.listen(std.net.Address.parseIp("0.0.0.0", 8080) catch unreachable);
while (true) {
const conn = try srv.accept();
// todo: keep track of connections
_ = async handleConnection(conn);
}
}