From 640839f3606f65e4dd492aec2d1653997ef1a4a4 Mon Sep 17 00:00:00 2001 From: SGavrl <277843151+SGavrl@users.noreply.github.com> Date: Tue, 4 Aug 2026 12:24:27 +0000 Subject: [PATCH] Make MCP navigation tests deterministic --- crates/obscura-cli/tests/mcp_client.rs | 99 +++++++++++++++++++++++--- 1 file changed, 89 insertions(+), 10 deletions(-) diff --git a/crates/obscura-cli/tests/mcp_client.rs b/crates/obscura-cli/tests/mcp_client.rs index ff1a8d9..c8ffc30 100644 --- a/crates/obscura-cli/tests/mcp_client.rs +++ b/crates/obscura-cli/tests/mcp_client.rs @@ -1,7 +1,78 @@ -use std::io::{BufRead, BufReader, Write}; +use std::io::{BufRead, BufReader, Read, Write}; +use std::net::{SocketAddr, TcpListener, TcpStream}; use std::process::{Child, ChildStdin, Command, Stdio}; +use std::sync::atomic::{AtomicBool, Ordering}; +use std::sync::Arc; +use std::thread::JoinHandle; +use std::time::Duration; const OBSCURA: &str = env!("CARGO_BIN_EXE_obscura"); +const TEST_PAGE: &str = r#"Example Domain +

Example Domain

Deterministic local MCP fixture.

+More information..."#; + +/// A loopback fixture keeps protocol tests independent of public-site bot +/// policy, DNS, and content changes. The previous example.com dependency can +/// return a Cloudflare block page, which tests the runner's egress reputation +/// rather than Obscura navigation, snapshots, or evaluation. +struct TestPageServer { + addr: SocketAddr, + stop: Arc, + thread: Option>, +} + +impl TestPageServer { + fn spawn() -> Self { + let listener = TcpListener::bind("127.0.0.1:0").expect("bind local fixture"); + let addr = listener.local_addr().expect("local fixture address"); + listener + .set_nonblocking(true) + .expect("nonblocking local fixture"); + let stop = Arc::new(AtomicBool::new(false)); + let thread_stop = Arc::clone(&stop); + let thread = std::thread::spawn(move || { + while !thread_stop.load(Ordering::Acquire) { + match listener.accept() { + Ok((mut stream, _)) => { + let _ = stream.set_read_timeout(Some(Duration::from_secs(1))); + let mut request = [0u8; 2048]; + let _ = stream.read(&mut request); + let response = format!( + "HTTP/1.1 200 OK\r\nContent-Type: text/html; charset=utf-8\r\nContent-Length: {}\r\nConnection: close\r\n\r\n{}", + TEST_PAGE.len(), + TEST_PAGE + ); + let _ = stream.write_all(response.as_bytes()); + let _ = stream.flush(); + } + Err(error) if error.kind() == std::io::ErrorKind::WouldBlock => { + std::thread::sleep(Duration::from_millis(2)); + } + Err(_) => break, + } + } + }); + Self { + addr, + stop, + thread: Some(thread), + } + } + + fn url(&self) -> String { + format!("http://{}/", self.addr) + } +} + +impl Drop for TestPageServer { + fn drop(&mut self) { + self.stop.store(true, Ordering::Release); + let _ = TcpStream::connect(self.addr); + if let Some(thread) = self.thread.take() { + let _ = thread.join(); + } + } +} // ── minimal MCP client ──────────────────────────────────────────────────────── @@ -16,6 +87,7 @@ impl McpClient { fn spawn() -> Self { let mut child = Command::new(OBSCURA) .args(["mcp"]) + .env("OBSCURA_ALLOW_PRIVATE_NETWORK", "1") .stdin(Stdio::piped()) .stdout(Stdio::piped()) .stderr(Stdio::null()) @@ -194,12 +266,13 @@ fn test_notifications_are_silent() { #[test] fn test_navigate_and_snapshot() { + let server = TestPageServer::spawn(); let mut c = McpClient::spawn(); - let nav = c.tool("browser_navigate", serde_json::json!({"url": "https://example.com"})); + let nav = c.tool("browser_navigate", serde_json::json!({"url": server.url()})); assert!(nav["result"]["isError"].is_null(), "navigate failed: {nav}"); let text = content_text(&nav); - assert!(text.contains("example.com"), "unexpected nav text: {text}"); + assert!(text.contains("127.0.0.1"), "unexpected nav text: {text}"); let snap = c.tool("browser_snapshot", serde_json::json!({})); assert!(snap["result"]["isError"].is_null(), "snapshot failed: {snap}"); @@ -210,8 +283,9 @@ fn test_navigate_and_snapshot() { #[test] fn test_evaluate() { + let server = TestPageServer::spawn(); let mut c = McpClient::spawn(); - c.tool("browser_navigate", serde_json::json!({"url": "https://example.com"})); + c.tool("browser_navigate", serde_json::json!({"url": server.url()})); let resp = c.tool( "browser_evaluate", @@ -223,8 +297,9 @@ fn test_evaluate() { #[test] fn test_evaluate_math() { + let server = TestPageServer::spawn(); let mut c = McpClient::spawn(); - c.tool("browser_navigate", serde_json::json!({"url": "https://example.com"})); + c.tool("browser_navigate", serde_json::json!({"url": server.url()})); let resp = c.tool( "browser_evaluate", @@ -237,8 +312,9 @@ fn test_evaluate_math() { #[test] fn test_wait_for_selector() { + let server = TestPageServer::spawn(); let mut c = McpClient::spawn(); - c.tool("browser_navigate", serde_json::json!({"url": "https://example.com"})); + c.tool("browser_navigate", serde_json::json!({"url": server.url()})); let resp = c.tool( "browser_wait_for", @@ -250,8 +326,9 @@ fn test_wait_for_selector() { #[test] fn test_wait_for_timeout() { + let server = TestPageServer::spawn(); let mut c = McpClient::spawn(); - c.tool("browser_navigate", serde_json::json!({"url": "https://example.com"})); + c.tool("browser_navigate", serde_json::json!({"url": server.url()})); let resp = c.tool( "browser_wait_for", @@ -277,21 +354,23 @@ fn test_unknown_tool_returns_error() { #[test] fn test_network_requests() { + let server = TestPageServer::spawn(); let mut c = McpClient::spawn(); - c.tool("browser_navigate", serde_json::json!({"url": "https://example.com"})); + c.tool("browser_navigate", serde_json::json!({"url": server.url()})); let resp = c.tool("browser_network_requests", serde_json::json!({})); let text = content_text(&resp); assert!( - text.contains("example.com") || text.contains("No network"), + text.contains("127.0.0.1") || text.contains("No network"), "unexpected: {text}" ); } #[test] fn test_close_resets_state() { + let server = TestPageServer::spawn(); let mut c = McpClient::spawn(); - c.tool("browser_navigate", serde_json::json!({"url": "https://example.com"})); + c.tool("browser_navigate", serde_json::json!({"url": server.url()})); let close = c.tool("browser_close", serde_json::json!({})); assert!(close["result"]["isError"].is_null());