+// voter: A simple CGI vote recorder, approval-voting-style
+//
+// This program is free software: you can redistribute it and/or modify it
+// under the terms of the GNU Affero General Public License as published
+// by the Free Software Foundation, version 3.
+
use rand::prelude::*;
+use std::collections::{HashMap, HashSet};
use std::io::prelude::*;
use std::path::{Path, PathBuf};
if path == "/" {
return Err(cgi::text_response(404, "(This is the voting place. You should have been given a more specific URL for the specific thing you've been invited to vote on.)"));
}
- if path.contains("..") || !path.starts_with("/") {
+ if path.contains("..") || !path.starts_with('/') {
return Err(invalid_path());
}
let dir = Path::new(&format!("{DATA_PATH}{path}")).to_path_buf();
let cookie = request
.headers()
.get(cgi::http::header::COOKIE)
- .map(|c| c.as_bytes())
+ .map(cgi::http::HeaderValue::as_bytes)
.and_then(|c| c.strip_prefix(COOKIE_NAME))
.and_then(|c| c.strip_prefix(b"="))
.ok_or_else(|| cgi::text_response(400, "Invalid cookie"))?;
}
}
+fn tally_votes(dir: PathBuf) -> std::io::Result<HashMap<String, HashSet<String>>> {
+ let mut tally: HashMap<String, HashSet<String>> = HashMap::new();
+ if let Ok(vfile) = std::fs::File::open(dir.join("votes")) {
+ for liner in std::io::BufReader::new(vfile).lines() {
+ let line = liner?;
+ if let Some((voter, datum)) = line.split_once(' ') {
+ if voter.len() == COOKIE_LENGTH {
+ if let Some((vote, candidate)) = datum.split_once(' ') {
+ if vote == "0" {
+ if let Some(entry) = tally.get_mut(candidate) {
+ entry.remove(voter);
+ }
+ } else if vote == "1" {
+ tally
+ .entry(candidate.to_owned())
+ .or_default()
+ .insert(voter.to_owned());
+ }
+ }
+ }
+ }
+ }
+ }
+ Ok(tally)
+}
+
+fn valid_id_char(c: &u8) -> bool {
+ (b'A'..=b'Z').contains(c) || (b'a'..=b'z').contains(c) || (b'0'..=b'9').contains(c)
+}
+
fn make_random_id() -> [u8; COOKIE_LENGTH] {
- std::iter::from_fn(random)
- .filter(|c| {
- (b'A'..=b'Z').contains(c) || (b'a'..=b'z').contains(c) || (b'0'..=b'9').contains(c)
- })
- .take(COOKIE_LENGTH)
- .collect::<Vec<_>>()
- .try_into()
- .unwrap()
+ let mut id = [0; COOKIE_LENGTH];
+ for c in &mut id {
+ while !valid_id_char(c) {
+ *c = random()
+ }
+ }
+ id
}
fn set_cookie(mut response: cgi::Response, path: &str) -> Result<cgi::Response, cgi::Response> {
COOKIE_NAME,
b"=",
&make_random_id(),
- b"; Secure HttpOnly SameSite=Strict Max-Age=30000000 Path=",
+ b"; Secure; HttpOnly; SameSite=Strict; Max-Age=30000000; Path=",
path.as_bytes(),
]
.concat(),
Ok(response)
}
+const HTML_HEADER: &str = "<!DOCTYPE html>
+<html>
+ <head>
+ <meta charset=\"utf-8\">
+ <title>Vote!</title>
+ <style>
+ th { font-size: 70%; text-align: left }
+ input { transform: scale(1.5) }
+ div { animation: 2s infinite linear spin }
+ @keyframes spin {
+ from { transform:rotate(0) }
+ to { transform:rotate(1turn) }
+ }
+ </style>
+ <script>
+ window.onload = function() {
+ for (cb of document.getElementsByTagName('input')) {
+ cb.addEventListener('click', (function(cb) {
+ return function() {
+ cb.style.display = 'none'
+ const spin = document.createElement('div')
+ spin.appendChild(document.createTextNode('⏳'))
+ cb.parentElement.insertBefore(spin, cb)
+
+ const req = new XMLHttpRequest()
+ req.addEventListener('load', function(e) {
+ cb.parentElement.removeChild(cb.previousElementSibling)
+ if (req.status == 200) {
+ cb.style.display = ''
+ const delta = cb.checked ? 1 : -1
+ const count_td = cb.parentElement.previousElementSibling
+ count_td.textContent = parseInt(count_td.textContent) + delta
+ } else {
+ cb.parentElement.insertBefore(document.createTextNode('❗'), cb)
+ }
+ })
+ req.open('PUT', window.location.href)
+ req.send((cb.checked ? 1 : 0) + ' ' + cb.parentElement.nextElementSibling.innerHTML)
+ }
+ })(cb))
+ cb.disabled = false
+ }
+ }
+ function num_cmp(a, b) {
+ return parseInt(b.textContent) - parseInt(a.textContent)
+ }
+ function str_cmp(a, b) {
+ if (a.textContent < b.textContent) return -1
+ if (a.textContent > b.textContent) return 1
+ return 0
+ }
+ function checked_cmp(a, b) {
+ vs = [a, b].map(x => {
+ const v = x.children[0].checked + 0
+ return isNaN(v) ? -1 : v
+ })
+ return vs[1] - vs[0]
+ }
+ function sort_table(col, cmp) {
+ const rows = Array.from(document.getElementsByTagName('tr'))
+ rows.shift()
+ rows.sort((a, b) => cmp(a.children[col], b.children[col]))
+ for (row of rows) {
+ row.parentElement.appendChild(row)
+ }
+ }
+ </script>
+ </head>
+ <body>
+ <table>
+ <tr>
+ <th onclick='sort_table(0, num_cmp)'>Count</th>
+ <th onclick='sort_table(1, checked_cmp)'>Vote</th>
+ <th onclick='sort_table(2, str_cmp)'>Candidate</th>
+ </tr>";
+const HTML_FOOTER: &str = "
+ </table>
+ </body>
+</html>";
+
+fn supports(tally: &HashMap<String, HashSet<String>>, me: &str, candidate: &str) -> bool {
+ tally
+ .get(candidate)
+ .map_or(false, |supporters| supporters.contains(me))
+}
+
fn prompt_for_vote(dir: PathBuf, request: cgi::Request) -> Result<cgi::Response, cgi::Response> {
let voter = get_voter(&request);
+ let me = if let Ok(id) = voter {
+ std::str::from_utf8(id).ok()
+ } else {
+ None
+ };
+ let tally =
+ tally_votes(dir.clone()).map_err(|_| cgi::text_response(503, "Couldn't tally votes"))?;
let cfile = std::fs::File::open(dir.join("candidates"))
.map_err(|_| cgi::text_response(503, "No candidates"))?;
let mut response = cgi::html_response(
200,
- std::iter::once(Ok("<html><body><table>".to_owned()))
- .chain(
- std::io::BufReader::new(cfile)
- .lines()
- .map(|rc| rc.map(|c| format!("<tr><td>{c}</td></tr>"))),
- )
- .chain(std::iter::once(Ok("</table></body></html>".to_owned())))
+ std::iter::once(Ok(HTML_HEADER.to_owned()))
+ .chain(std::io::BufReader::new(cfile).lines().map(|rc| {
+ rc.map(|c| {
+ let count = tally.get(&c).map_or(0, std::collections::HashSet::len);
+ let checked = if me.map_or(false, |me| supports(&tally, me, &c)) {
+ "checked"
+ } else {
+ ""
+ };
+ format!(
+ "<tr>
+ <td>{count}</td>
+ <td><input type=\"checkbox\" autocomplete=\"off\" {checked} disabled></td>
+ <td>{c}</td>
+ </tr>"
+ )
+ })
+ }))
+ .chain(std::iter::once(Ok(HTML_FOOTER.to_owned())))
.collect::<std::io::Result<String>>()
.map_err(|_| cgi::text_response(503, "Missing candidates"))?,
);
.create(true)
.open(vpath)?;
let mut vlock = fd_lock::RwLock::new(vfile);
- vlock.write()?.write(&datum)?;
+ vlock.write()?.write_all(&datum)?;
Ok(())
}
{
return Err(cgi::text_response(415, "Invalid vote"));
}
- write_vote(dir, &get_voter(&request)?, body)
+ write_vote(dir, get_voter(&request)?, body)
.map_err(|_| cgi::text_response(503, "Couldn't record vote"))?;
Ok(cgi::text_response(200, "Vote recorded"))
}
fn respond(request: cgi::Request) -> Result<cgi::Response, cgi::Response> {
let dir = validate_path(request.uri().path())?;
- match request.method() {
- &cgi::http::Method::HEAD => prompt_for_vote(dir, request).map(strip_body),
- &cgi::http::Method::GET => prompt_for_vote(dir, request),
- &cgi::http::Method::PUT => record_vote(dir, request),
+ match *request.method() {
+ cgi::http::Method::HEAD => prompt_for_vote(dir, request).map(strip_body),
+ cgi::http::Method::GET => prompt_for_vote(dir, request),
+ cgi::http::Method::PUT => record_vote(dir, request),
_ => Err(cgi::text_response(405, "Huh?")),
}
}
projects / voter / blobdiff