From 5002f93fd593ab5d99067915fef88cbc96db3be9 Mon Sep 17 00:00:00 2001
From: Matt Clarkson <matthew.clarkson@arm.com>
Date: Wed, 5 Feb 2025 12:18:50 +0000
Subject: [PATCH 1/3] test(e2e): add `sniff` helper

Can be used to sniff for text in a stream.

Useful for determining listening port for servers.
---
 e2e/binary/BUILD.bazel |  1 +
 e2e/binary/__init__.py |  3 ++-
 e2e/binary/conftest.py |  3 +--
 e2e/binary/sniff.py    | 44 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 48 insertions(+), 3 deletions(-)
 create mode 100644 e2e/binary/sniff.py

diff --git a/e2e/binary/BUILD.bazel b/e2e/binary/BUILD.bazel
index ede035ea..a2fcbcb2 100644
--- a/e2e/binary/BUILD.bazel
+++ b/e2e/binary/BUILD.bazel
@@ -17,6 +17,7 @@ py_library(
         "difference.py",
         "relative.py",
         "runfile.py",
+        "sniff.py",
         "tool.py",
     ],
     # FIXME: when `rules_python` hermetic launcher works on Windows
diff --git a/e2e/binary/__init__.py b/e2e/binary/__init__.py
index f79c1894..1798572f 100644
--- a/e2e/binary/__init__.py
+++ b/e2e/binary/__init__.py
@@ -2,6 +2,7 @@ from __future__ import annotations
 
 from binary.difference import Diff
 from binary.relative import Relative
+from binary.sniff import sniff
 from binary.tool import Tool
 
-__all__ = ("Diff", "Tool", "Relative")
+__all__ = ("sniff", "Diff", "Tool", "Relative")
diff --git a/e2e/binary/conftest.py b/e2e/binary/conftest.py
index f85f9f59..b83c6382 100644
--- a/e2e/binary/conftest.py
+++ b/e2e/binary/conftest.py
@@ -2,13 +2,12 @@ from __future__ import annotations
 
 from pytest import fixture
 
-from .difference import Diff
 from .difference import repr as diff
 from .relative import Relative
 from .runfile import Runfile, SupportsRlocation, create
 from .tool import Tool
 
-__all__ = ("Diff", "Relative", "Tool", "Runfile")
+__all__ = ("Relative", "Tool", "Runfile")
 
 
 @fixture
diff --git a/e2e/binary/sniff.py b/e2e/binary/sniff.py
new file mode 100644
index 00000000..d6ef7c4e
--- /dev/null
+++ b/e2e/binary/sniff.py
@@ -0,0 +1,44 @@
+from __future__ import annotations
+
+from concurrent.futures import Executor, ThreadPoolExecutor, TimeoutError
+from os import read
+from re import Match, Pattern, compile
+from select import select
+
+
+def consume(fd: int, /) -> bytes:
+    buffer = b""
+    while r := read(fd, 1024):
+        buffer += r
+        if len(r) < 1024:
+            break
+    return buffer
+
+
+def detect(fd: int, regex: Pattern[str], /, timeout: int) -> Match[str]:
+    buffer = b""
+    while True:
+        ready, _, _ = select((fd,), (), (), timeout)
+        if fd not in ready:
+            raise TimeoutError(f"failed to select on {fd}")
+
+        buffer += consume(fd)
+        line, found, buffer = buffer.partition(b"\n")
+        if match := regex.match(line.decode("utf8")):
+            return match
+
+
+def pooled(pool: Executor, fd: int, regex: Pattern[str], /, timeout: int) -> str:
+    future = pool.submit(detect, fd, regex, timeout)
+    return future.result(timeout=timeout)
+
+
+def threaded(fd: int, regex: Pattern[str], /, threads: int, timeout: int) -> str:
+    with ThreadPoolExecutor(max_workers=threads) as pool:
+        return pooled(pool, fd, regex, timeout=timeout)
+
+
+def sniff(fd: int, regex: Pattern[str] | str, /, timeout: int) -> str:
+    if isinstance(regex, str):
+        regex = compile(regex)
+    return threaded(fd, regex, timeout=timeout, threads=1)
-- 
GitLab


From fedfff3c882c60649fc427fc65cb7e5e313959b2 Mon Sep 17 00:00:00 2001
From: Matt Clarkson <matthew.clarkson@arm.com>
Date: Wed, 5 Feb 2025 12:31:18 +0000
Subject: [PATCH 2/3] test(e2e): add `port.listening` helper

Can be used to skip tests when a port is in use.
---
 e2e/binary/BUILD.bazel | 1 +
 e2e/binary/port.py     | 8 ++++++++
 2 files changed, 9 insertions(+)
 create mode 100644 e2e/binary/port.py

diff --git a/e2e/binary/BUILD.bazel b/e2e/binary/BUILD.bazel
index a2fcbcb2..24cf276d 100644
--- a/e2e/binary/BUILD.bazel
+++ b/e2e/binary/BUILD.bazel
@@ -15,6 +15,7 @@ py_library(
         "__init__.py",
         "conftest.py",
         "difference.py",
+        "port.py",
         "relative.py",
         "runfile.py",
         "sniff.py",
diff --git a/e2e/binary/port.py b/e2e/binary/port.py
new file mode 100644
index 00000000..221eb68a
--- /dev/null
+++ b/e2e/binary/port.py
@@ -0,0 +1,8 @@
+from __future__ import annotations
+
+from socket import AF_INET, SOCK_STREAM, socket
+
+
+def listening(port: int, host: str = "localhost") -> bool:
+    with socket(AF_INET, SOCK_STREAM) as s:
+        return s.connect_ex((host, port)) == 0
-- 
GitLab


From e6ffb76c6ef69d222d12a9763ec73dd144a42c0c Mon Sep 17 00:00:00 2001
From: Matt Clarkson <matthew.clarkson@arm.com>
Date: Wed, 5 Feb 2025 11:12:13 +0000
Subject: [PATCH 3/3] test(greenbean): add serve test

---
 e2e/binary/greenbean/BUILD.bazel   | 23 +++++++++++++++++------
 e2e/binary/greenbean/expected.html |  5 +++++
 e2e/binary/greenbean/serve.py      | 30 ++++++++++++++++++++++++++++++
 e2e/binary/sniff.py                |  4 ++++
 4 files changed, 56 insertions(+), 6 deletions(-)
 create mode 100644 e2e/binary/greenbean/expected.html
 create mode 100644 e2e/binary/greenbean/serve.py

diff --git a/e2e/binary/greenbean/BUILD.bazel b/e2e/binary/greenbean/BUILD.bazel
index d8d31d97..d34920bb 100644
--- a/e2e/binary/greenbean/BUILD.bazel
+++ b/e2e/binary/greenbean/BUILD.bazel
@@ -1,11 +1,22 @@
-load("@bazel_skylib//rules:build_test.bzl", "build_test")
+load("@rules_python_pytest//python_pytest:defs.bzl", "py_pytest_test")
 
-# TODO: write an _actual_ test for `greenbean`
+py_pytest_test(
+    name = "pytest",
+    size = "small",
+    srcs = ["serve.py"],
+    data = [
+        "expected.html",
+        "@ape//ape:greenbean",
+    ],
+    deps = [
+        "//binary:pytest",
+    ],
+)
 
-build_test(
+test_suite(
     name = "greenbean",
-    size = "small",
-    tags = ["stub"],
-    targets = ["@ape//ape:greenbean"],
+    tests = [
+        ":pytest",
+    ],
     visibility = ["//:__subpackages__"],
 )
diff --git a/e2e/binary/greenbean/expected.html b/e2e/binary/greenbean/expected.html
new file mode 100644
index 00000000..9010ee2d
--- /dev/null
+++ b/e2e/binary/greenbean/expected.html
@@ -0,0 +1,5 @@
+<!doctype html>
+<title>hello world</title>
+<h1>hello world</h1>
+<p>this is a fun webpage
+<p>hosted by greenbean
diff --git a/e2e/binary/greenbean/serve.py b/e2e/binary/greenbean/serve.py
new file mode 100644
index 00000000..9c5d79ba
--- /dev/null
+++ b/e2e/binary/greenbean/serve.py
@@ -0,0 +1,30 @@
+from __future__ import annotations
+
+from os import read
+from pathlib import Path
+from select import select
+from shutil import copyfileobj
+from subprocess import PIPE, Popen
+from urllib.request import urlopen
+
+from binary import Diff, Relative, Tool, sniff
+from binary.port import listening
+from pytest import mark
+
+
+@mark.skipif(listening(8080), reason="port 8080 is in use")
+def test_serve(tool: Tool, relative: Relative, tmp_path: Path) -> None:
+    binary = tool("greenbean")
+    expected = relative("expected.html")
+    output = tmp_path / "output.html"
+
+    cmd = (binary, "1")
+    server = Popen(cmd, stderr=PIPE, encoding="utf8", cwd=tmp_path)
+    match = sniff(server.stderr.fileno(), r"listening on (http://.+)", timeout=2)
+    host = match.group(1)
+
+    with urlopen(host) as src, open(output, "w+b") as dst:
+        assert 200 <= src.status < 300
+        copyfileobj(src, dst)
+
+    assert Diff(expected) == Diff(output)
diff --git a/e2e/binary/sniff.py b/e2e/binary/sniff.py
index d6ef7c4e..cd98538a 100644
--- a/e2e/binary/sniff.py
+++ b/e2e/binary/sniff.py
@@ -23,7 +23,11 @@ def detect(fd: int, regex: Pattern[str], /, timeout: int) -> Match[str]:
             raise TimeoutError(f"failed to select on {fd}")
 
         buffer += consume(fd)
+        if not buffer:
+            raise EOFError("no data to sniff")
         line, found, buffer = buffer.partition(b"\n")
+        if not found:
+            continue
         if match := regex.match(line.decode("utf8")):
             return match
 
-- 
GitLab