mini-static 0.18.0

A secure, async static file server with streaming, traversal protection, and connection limits.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281

use mini_static::Server;
use std::fs;
use std::time::Duration;
use tempfile::TempDir;
use tokio::io::{AsyncReadExt, AsyncWriteExt};
use tokio::net::TcpStream;
use tokio::time::timeout;

/// Read from `conn` until `needle` appears in the accumulated bytes, or `bound` elapses.
/// Bounded so a test hangs for at most `bound` instead of forever if the expected data
/// never arrives (A2: every wait has a stated upper bound).
async fn read_until(conn: &mut TcpStream, needle: &str, bound: Duration) -> String {
    let mut buf = Vec::new();
    let mut chunk = [0u8; 4096];

    timeout(bound, async {
        loop {
            let n = conn.read(&mut chunk).await.expect("read failed");
            assert!(n > 0, "connection closed before {needle:?} appeared");
            buf.extend_from_slice(&chunk[..n]);
            if String::from_utf8_lossy(&buf).contains(needle) {
                break;
            }
        }
    })
    .await
    .unwrap_or_else(|_| {
        panic!(
            "timed out waiting for {needle:?}, got so far: {}",
            String::from_utf8_lossy(&buf)
        )
    });

    String::from_utf8_lossy(&buf).into_owned()
}

#[tokio::test]
async fn live_reload_disabled_by_default_serves_plain_html_and_404s_reload_endpoint() {
    let root = TempDir::new().unwrap();
    fs::write(
        root.path().join("index.html"),
        b"<html><body>hi</body></html>",
    )
    .unwrap();

    let server = Server::new(root.path()).unwrap();
    let (port, handle) = server.run_ephemeral().await.unwrap();
    let addr = format!("127.0.0.1:{port}");

    let mut conn = TcpStream::connect(&addr).await.unwrap();
    conn.write_all(b"GET /index.html HTTP/1.1\r\nHost: localhost\r\nConnection: close\r\n\r\n")
        .await
        .unwrap();
    let mut response_data = Vec::new();
    conn.read_to_end(&mut response_data).await.unwrap();
    let response = String::from_utf8_lossy(&response_data);

    assert!(response.contains("HTTP/1.1 200"));
    assert!(
        !response.contains("EventSource"),
        "no live-reload script should be injected when with_live_reload() was never called"
    );

    let mut conn = TcpStream::connect(&addr).await.unwrap();
    let request = format!(
        "GET {} HTTP/1.1\r\nHost: localhost\r\nConnection: close\r\n\r\n",
        mini_static::LIVE_RELOAD_PATH
    );
    conn.write_all(request.as_bytes()).await.unwrap();
    let mut response_data = Vec::new();
    conn.read_to_end(&mut response_data).await.unwrap();
    let response = String::from_utf8_lossy(&response_data);
    assert!(
        response.contains("HTTP/1.1 404"),
        "reload endpoint should not be routed when live-reload is disabled, got: {response}"
    );

    handle.shutdown().await;
}

#[tokio::test]
async fn live_reload_enabled_injects_script_into_html_with_correct_content_length() {
    let root = TempDir::new().unwrap();
    fs::write(
        root.path().join("index.html"),
        b"<html><body>hi</body></html>",
    )
    .unwrap();

    let server = Server::new(root.path()).unwrap().with_live_reload();
    let (port, handle) = server.run_ephemeral().await.unwrap();
    let addr = format!("127.0.0.1:{port}");

    let mut conn = TcpStream::connect(&addr).await.unwrap();
    conn.write_all(b"GET /index.html HTTP/1.1\r\nHost: localhost\r\nConnection: close\r\n\r\n")
        .await
        .unwrap();
    let mut response_data = Vec::new();
    conn.read_to_end(&mut response_data).await.unwrap();
    let response = String::from_utf8_lossy(&response_data);

    assert!(response.contains("HTTP/1.1 200"));
    assert!(response.contains(mini_static::LIVE_RELOAD_PATH));
    assert!(
        response.find("EventSource").unwrap() < response.find("</body>").unwrap(),
        "script must be injected before the closing body tag, got: {response}"
    );

    let content_length: usize = response
        .lines()
        .find(|l| l.to_lowercase().starts_with("content-length:"))
        .and_then(|l| l.split(':').nth(1))
        .and_then(|v| v.trim().parse().ok())
        .expect("Content-Length header present");
    let body = response.split("\r\n\r\n").nth(1).unwrap();
    assert_eq!(
        content_length,
        body.len(),
        "Content-Length must reflect the injected body, not the on-disk file size"
    );

    handle.shutdown().await;
}

#[tokio::test]
async fn live_reload_enabled_leaves_non_html_files_byte_identical() {
    let root = TempDir::new().unwrap();
    let css = b"body { color: red; }".to_vec();
    fs::write(root.path().join("style.css"), &css).unwrap();

    let server = Server::new(root.path()).unwrap().with_live_reload();
    let (port, handle) = server.run_ephemeral().await.unwrap();
    let addr = format!("127.0.0.1:{port}");

    let mut conn = TcpStream::connect(&addr).await.unwrap();
    conn.write_all(b"GET /style.css HTTP/1.1\r\nHost: localhost\r\nConnection: close\r\n\r\n")
        .await
        .unwrap();
    let mut response_data = Vec::new();
    conn.read_to_end(&mut response_data).await.unwrap();
    let response = String::from_utf8_lossy(&response_data);

    assert!(response.contains("HTTP/1.1 200"));
    assert!(response.ends_with(&String::from_utf8(css).unwrap()));

    handle.shutdown().await;
}

#[tokio::test]
async fn live_reload_sse_endpoint_broadcasts_file_change_to_connected_client() {
    // Watchers run over source folders only (the served root is the output dir and is
    // never watched — that separation is what breaks the build feedback loop). A source
    // file with no owning pipeline (no CSS bundle, not a script) is re-broadcast as-is.
    let src = TempDir::new().unwrap();
    let out = TempDir::new().unwrap();
    fs::write(out.path().join("index.html"), b"<html></html>").unwrap();

    let server = Server::new(out.path())
        .unwrap()
        .with_live_reload()
        .with_source_folder(src.path())
        .unwrap();
    let (port, handle) = server.run_ephemeral().await.unwrap();
    let addr = format!("127.0.0.1:{port}");

    let mut conn = TcpStream::connect(&addr).await.unwrap();
    let request = format!(
        "GET {} HTTP/1.1\r\nHost: localhost\r\n\r\n",
        mini_static::LIVE_RELOAD_PATH
    );
    conn.write_all(request.as_bytes()).await.unwrap();

    let headers = read_until(&mut conn, "\r\n\r\n", Duration::from_secs(2)).await;
    assert!(headers.contains("HTTP/1.1 200"));
    assert!(headers
        .to_lowercase()
        .contains("content-type: text/event-stream"));

    // Give the watcher's first poll pass (500ms, per `watcher::start_watching`) time to
    // complete before writing, so the write is seen as a change, not the initial baseline.
    tokio::time::sleep(Duration::from_millis(700)).await;
    fs::write(src.path().join("style.css"), b"body{}").unwrap();

    let frame = read_until(&mut conn, "\n\n", Duration::from_secs(2)).await;
    assert!(
        frame.contains("event: css"),
        "expected an SSE frame for the new .css source file, got: {frame}"
    );

    handle.shutdown().await;
}

// Disproves the prior implementation, which wrapped the *entire* connection lifetime
// (not just the header-read phase) in `header_timeout`. Under that implementation, an
// SSE connection surviving past `header_timeout` was aborted mid-stream — after the `200
// OK` headers had already been flushed but before any further frame — which a real
// browser reports as `net::ERR_INCOMPLETE_CHUNKED_ENCODING`. This test uses a short
// `header_timeout` and waits well past it before triggering a change, so it would have
// failed (connection reset, no frame received) against that implementation.
#[tokio::test]
async fn live_reload_sse_connection_survives_past_header_timeout() {
    let src = TempDir::new().unwrap();
    let out = TempDir::new().unwrap();
    fs::write(out.path().join("index.html"), b"<html></html>").unwrap();

    let header_timeout = Duration::from_millis(100);
    let server = Server::new(out.path())
        .unwrap()
        .with_live_reload()
        .with_source_folder(src.path())
        .unwrap();
    let (port, handle) = server.run(header_timeout).await.unwrap();
    let addr = format!("127.0.0.1:{port}");

    let mut conn = TcpStream::connect(&addr).await.unwrap();
    let request = format!(
        "GET {} HTTP/1.1\r\nHost: localhost\r\n\r\n",
        mini_static::LIVE_RELOAD_PATH
    );
    conn.write_all(request.as_bytes()).await.unwrap();

    let headers = read_until(&mut conn, "\r\n\r\n", Duration::from_secs(2)).await;
    assert!(headers.contains("HTTP/1.1 200"));

    // Outlive header_timeout several times over, well past the watcher's bounded 500ms
    // poll interval, so any premature connection abort has ample opportunity to happen
    // first — and clears the poll interval by a wide enough margin to avoid flakiness.
    tokio::time::sleep(header_timeout * 8).await;
    fs::write(src.path().join("style.css"), b"body{}").unwrap();

    let frame = read_until(&mut conn, "\n\n", Duration::from_secs(2)).await;
    assert!(
        frame.contains("event: css"),
        "SSE connection should still be alive long after header_timeout elapsed, got: {frame}"
    );

    // Close the client side first so the server observes EOF and the connection's task
    // ends on its own — shutdown()'s drain-timeout/abort behavior for a connection that
    // *doesn't* close on its own is covered separately, below.
    drop(conn);
    tokio::time::timeout(Duration::from_secs(2), handle.shutdown())
        .await
        .expect("shutdown should complete promptly once the client has disconnected");
}

// Disproves an implementation where `ServerHandle::shutdown()` waits unconditionally for
// every in-flight connection to finish on its own: an open live-reload SSE connection has
// no natural end (it stays open until a file changes), so that implementation would hang
// forever here. `shutdown_with_timeout` with a short grace period must instead abort it.
#[tokio::test]
async fn live_reload_shutdown_aborts_a_still_open_sse_connection_after_the_drain_timeout() {
    let root = TempDir::new().unwrap();
    fs::write(root.path().join("index.html"), b"<html></html>").unwrap();

    let server = Server::new(root.path()).unwrap().with_live_reload();
    let (port, handle) = server.run_ephemeral().await.unwrap();
    let addr = format!("127.0.0.1:{port}");

    let mut conn = TcpStream::connect(&addr).await.unwrap();
    let request = format!(
        "GET {} HTTP/1.1\r\nHost: localhost\r\n\r\n",
        mini_static::LIVE_RELOAD_PATH
    );
    conn.write_all(request.as_bytes()).await.unwrap();
    let headers = read_until(&mut conn, "\r\n\r\n", Duration::from_secs(2)).await;
    assert!(
        headers.contains("HTTP/1.1 200"),
        "SSE connection should be established, got: {headers}"
    );

    // Never triggers a file change and never closes `conn` — the SSE connection is left
    // genuinely open, with nothing that would end it on its own.
    tokio::time::timeout(
        Duration::from_secs(2),
        handle.shutdown_with_timeout(Duration::from_millis(200)),
    )
    .await
    .expect(
        "shutdown_with_timeout should abort the open connection at its drain timeout, not hang",
    );
}