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|
const std = @import("std");
const zws = @import("zws");
const pq = @import("pq");
const mustache = @import("mustache");
const smtp = @import("smtp");
const Params = zws.Params;
const Err = error{
Unexpected,
AccessDenied,
OutOfMemory,
InputOutput,
SystemResources,
IsDir,
OperationAborted,
BrokenPipe,
ConnectionResetByPeer,
ConnectionTimedOut,
NotOpenForReading,
NetNameDeleted,
WouldBlock,
StreamTooLong,
Malformatted,
InvalidLength,
InvalidCharacter,
NoSpaceLeft,
PqError,
ColumnNotFound,
DiskQuota,
FileTooBig,
DeviceBusy,
InvalidArgument,
NotOpenForWriting,
LockViolation,
InvalidRequestMethod,
};
const Ctx = struct {
db: pq.Db,
pub fn clone(self: @This()) Ctx {
return Ctx{
.db = self.db,
};
}
pub fn deinit(self: @This()) void {
_ = self;
}
};
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const Request = struct {
method: std.http.Method,
target: []const u8,
};
const ResponseTransfer = union(enum) {
content_length: u64,
chunked: void,
none: void,
};
const Headers = struct {
const Entry = struct { key: []const u8, val: []const u8 };
_internal: std.ArrayList(Entry),
fn init(allocator: std.mem.Allocator) Headers {
return .{ ._internal = std.ArrayList(Entry).init(allocator) };
}
fn append(self: *@This(), key: []const u8, val: []const u8) !void {
try self._internal.append(.{ .key = key, .val = val });
}
};
const Response = struct {
allocator: std.mem.Allocator,
request: Request,
// TODO other fields and writer function to write headers and body to stdout
status: std.http.Status,
transfer_encoding: ResponseTransfer,
headers: Headers,
fn reader(_: @This()) std.fs.File.Reader {
return std.io.getStdIn().reader();
}
fn do(self: @This()) !void {
for (self.headers._internal.items) |tup| {
try std.io.getStdOut().writeAll(tup.key);
try std.io.getStdOut().writeAll(": ");
try std.io.getStdOut().writeAll(tup.val);
try std.io.getStdOut().writeAll("\r\n");
}
try std.io.getStdOut().writeAll("\r\n");
}
fn writer(_: @This()) std.fs.File.Writer {
return std.io.getStdOut().writer();
}
fn finish(_: @This()) !void {
// TODO Write empty lines? or just do nothing
}
};
const Rtr = zws.Router(*Response, Ctx, Err);
const router = Rtr{
.allocator = gpa.allocator(),
.handlers = &[_]Rtr.Handler{
.{
.method = .GET,
.pattern = "/api/comment",
.handle_fn = get_comment,
},
.{
.method = .POST,
.pattern = "/api/comment",
.handle_fn = post_comment,
},
.{
.method = .GET,
.pattern = "/api/form",
.handle_fn = get_form,
},
},
.notfound = notfound,
};
/// Run as a CGI program!
pub fn main() !void {
const allocator = gpa.allocator();
const db_url = std.os.getenv("DATABASE_URL") orelse "postgresql://comments@localhost/comments";
var db = try pq.Db.init(db_url);
// try db.exec(@embedFile("migrations/0_init.sql"));
// try db.exec(@embedFile("migrations/1_capcha.sql"));
defer db.deinit();
const req = Request{
.method = std.meta.stringToEnum(std.http.Method, std.os.getenv("REQUEST_METHOD") orelse "GET") orelse {
return error.InvalidRequestMethod;
},
.target = std.os.getenv("REQUEST_URI") orelse "/",
};
var res = Response{
.allocator = allocator,
.request = req,
.status = .bad_request,
.transfer_encoding = .none,
.headers = Headers.init(allocator),
};
const ctx = Ctx{ .db = db };
try router.handle(&res, ctx);
}
fn notfound(res: *Response, _: Ctx) Err!void {
const rr = @embedFile("templates/notfound.html");
try constresponse(res, rr, .not_found);
}
fn badrequest(res: *Response, _: Ctx) Err!void {
const rr = @embedFile("templates/badrequest.html");
try constresponse(res, rr, .bad_request);
}
fn constresponse(res: *Response, rr: []const u8, status: std.http.Status) Err!void {
res.status = status;
res.transfer_encoding = .{ .content_length = rr.len };
try res.headers.append("content-type", "text/html");
try res.do();
try res.writer().writeAll(rr);
try res.finish();
}
fn get_comment(res: *Response, ctx: Ctx, _: Params) Err!void {
var p = try zws.Path.parse(res.allocator, res.request.target);
defer p.deinit();
const url: []const u8 = try p.get_query_param("url") orelse {
try badrequest(res, ctx);
return;
};
const Comment = struct {
author: []const u8,
comment: []const u8,
ts: []const u8,
};
var comments = std.ArrayList(Comment).init(res.allocator);
var stmt = try ctx.db.prepare_statement(res.allocator,
\\ select author,comment,ts from comments where url = $1 order by ts
);
defer stmt.deinit();
try stmt.bind(0, url);
while (try stmt.step()) {
const cmt = try stmt.read_struct(Comment);
try comments.append(cmt);
}
const rr = @embedFile("templates/comments.html");
const tt = comptime mustache.parseComptime(rr, .{}, .{});
res.transfer_encoding = .chunked;
try res.headers.append("content-type", "text/html");
try res.do();
const data = struct {
comments: []const Comment,
};
try mustache.render(tt, data{
.comments = comments.items,
}, res.writer());
try res.finish();
}
fn post_comment(res: *Response, ctx: Ctx, _: Params) Err!void {
var body_aa = std.ArrayList(u8).init(res.allocator);
try res.reader().readAllArrayList(&body_aa, 1_000_000);
var body = try body_aa.toOwnedSlice();
var form = try zws.Form.parse(res.allocator, body);
const Form = struct {
url: []const u8,
capcha_id: []const u8,
author: []const u8,
comment: []const u8,
capcha_answer: []const u8,
};
const form_val = form.form_to_struct(Form) catch {
try badrequest(res, ctx);
return;
};
// Validate the capcha
{
var stmt = try ctx.db.prepare_statement(res.allocator, "select answer from capchas where id = $1");
defer stmt.deinit();
try stmt.bind(0, form_val.capcha_id);
if (!try stmt.step()) {
std.log.err("missing capcha_id {s}", .{form_val.capcha_id});
try badrequest(res, ctx);
return;
}
const ans = try stmt.read_column(0, []const u8);
if (!std.mem.eql(u8, ans, form_val.capcha_answer)) {
try constresponse(res, @embedFile("templates/capchainvalid.html"), std.http.Status.unauthorized);
return;
}
}
// Add the comment...
{
var stmt = try ctx.db.prepare_statement(res.allocator, "insert into comments(url,author,comment) values($1, $2, $3)");
defer stmt.deinit();
try stmt.bind(0, form_val.url);
try stmt.bind(1, form_val.author);
try stmt.bind(2, form_val.comment);
_ = try stmt.step();
}
// Send me an email
const rr = @embedFile("templates/notification.txt");
const tt = comptime mustache.parseComptime(rr, .{}, .{});
const Data = struct { url: []const u8, author: []const u8, comment: []const u8 };
const notification = try mustache.allocRender(res.allocator, tt, Data{
.url = form_val.url,
.author = form_val.author,
.comment = form_val.comment,
});
const smtp_username = std.os.getenv("SMTP_USERNAME") orelse "comments@mfashby.net";
const smtp_password = std.os.getenv("SMTP_PASSWORD") orelse "foobar";
const notification_address = std.os.getenv("NOTIFICATION_ADDRESS") orelse "martin@mfashby.net";
const smtp_server = std.os.getenv("SMTP_SERVER") orelse "mail.mfashby.net:587";
smtp.send_mail(res.allocator, smtp_server, .{ .user = smtp_username, .pass = smtp_password }, smtp_username, &[_][]const u8{notification_address}, notification) catch |err| {
std.log.err("failed to send notification email {}", .{err});
};
// And redirect!
res.transfer_encoding = .none;
res.status = .found;
try res.headers.append("location", form_val.url);
try res.do();
try res.finish();
}
fn get_form(res: *Response, ctx: Ctx, _: Params) Err!void {
var p = try zws.Path.parse(res.allocator, res.request.target);
defer p.deinit();
const url: []const u8 = try p.get_query_param("url") orelse {
try badrequest(res, ctx);
return;
};
var stmt = try ctx.db.prepare_statement(res.allocator, "select id, question from capchas order by random() limit 1");
defer stmt.deinit();
if (!try stmt.step()) {
std.log.err("no capcha!", .{});
try badrequest(res, ctx);
return;
}
const Capcha = struct {
id: []const u8,
question: []const u8,
};
const capcha = try stmt.read_struct(Capcha);
const rr = @embedFile("templates/form.html");
const tt = comptime mustache.parseComptime(rr, .{}, .{});
res.transfer_encoding = .chunked;
try res.headers.append("content-type", "text/html");
try res.do();
// For some reason, mustache.render won't work with anonymous struct
const data = struct {
capcha_id: []const u8,
capcha_question: []const u8,
url: []const u8,
};
try mustache.render(tt, data{
.capcha_id = capcha.id,
.capcha_question = capcha.question,
.url = url,
}, res.writer());
try res.finish();
}
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