Implement the first real test of gpt4all-chat (#3116)

Signed-off-by: Jared Van Bortel <jared@nomic.ai>

gpt4all-chat/tests/python/test_server_api.py

@@ -0,0 +1,87 @@
+import os
+import signal
+import subprocess
+import sys
+import tempfile
+import textwrap
+from pathlib import Path
+from subprocess import CalledProcessError
+from typing import Any, Iterator
+
+import pytest
+import requests
+from urllib3 import Retry
+
+from . import config
+
+
+class Requestor:
+    def __init__(self) -> None:
+        self.session = requests.Session()
+        self.http_adapter = self.session.adapters['http://']
+
+    def get(self, path: str, *, wait: bool = False) -> Any:
+        return self._request('GET', path, wait)
+
+    def _request(self, method: str, path: str, wait: bool) -> Any:
+        if wait:
+            retry = Retry(total=None, connect=10, read=False, status=0, other=0, backoff_factor=.01)
+        else:
+            retry = Retry(total=False)
+        self.http_adapter.max_retries = retry  # type: ignore[attr-defined]
+
+        resp = self.session.request(method, f'http://localhost:4891/v1/{path}')
+        resp.raise_for_status()
+        return resp.json()
+
+
+request = Requestor()
+
+
+@pytest.fixture
+def chat_server_config() -> Iterator[dict[str, str]]:
+    if os.name != 'posix' or sys.platform == 'darwin':
+        pytest.skip('Need non-Apple Unix to use alternate config path')
+
+    with tempfile.TemporaryDirectory(prefix='gpt4all-test') as td:
+        tmpdir = Path(td)
+        xdg_confdir = tmpdir / 'config'
+        app_confdir = xdg_confdir / 'nomic.ai'
+        app_confdir.mkdir(parents=True)
+        with open(app_confdir / 'GPT4All.ini', 'w') as conf:
+            conf.write(textwrap.dedent(f"""\
+                [General]
+                serverChat=true
+
+                [download]
+                lastVersionStarted={config.APP_VERSION}
+
+                [network]
+                isActive=false
+                usageStatsActive=false
+            """))
+        yield dict(
+            os.environ,
+            XDG_CACHE_HOME=str(tmpdir / 'cache'),
+            XDG_DATA_HOME=str(tmpdir / 'share'),
+            XDG_CONFIG_HOME=str(xdg_confdir),
+            APPIMAGE=str(tmpdir),  # hack to bypass SingleApplication
+        )
+
+
+@pytest.fixture
+def chat_server(chat_server_config: dict[str, str]) -> Iterator[None]:
+    chat_executable = Path(os.environ['CHAT_EXECUTABLE']).absolute()
+    with subprocess.Popen(chat_executable, env=chat_server_config) as process:
+        try:
+            yield
+        except:
+            process.kill()
+            raise
+        process.send_signal(signal.SIGINT)
+        if retcode := process.wait():
+            raise CalledProcessError(retcode, process.args)
+
+
+def test_list_models_empty(chat_server: None) -> None:
+    assert request.get('models', wait=True) == {'object': 'list', 'data': []}