Add flag to http client to allow for the client to be dryrun (#43)

Author: lukemassa

pykube/http.py

@@ -160,7 +160,7 @@ class HTTPClient:
     Client for interfacing with the Kubernetes API.
     """
 
-    def __init__(self, config: KubeConfig, timeout: float = DEFAULT_HTTP_TIMEOUT):
+    def __init__(self, config: KubeConfig, timeout: float = DEFAULT_HTTP_TIMEOUT, dry_run: bool = False):
         """
         Creates a new instance of the HTTPClient.
 
@@ -170,6 +170,7 @@ def __init__(self, config: KubeConfig, timeout: float = DEFAULT_HTTP_TIMEOUT):
         self.config = config
         self.timeout = timeout
         self.url = self.config.cluster["server"]
+        self.dry_run = dry_run
 
         session = requests.Session()
         session.headers['User-Agent'] = f'pykube-ng/{__version__}'
@@ -242,6 +243,11 @@ def get_kwargs(self, **kwargs) -> dict:
         if 'timeout' not in kwargs:
             # apply default HTTP timeout
             kwargs['timeout'] = self.timeout
+        if self.dry_run:
+            # Add http query param for dryRun
+            params = kwargs.get('params', {})
+            params['dryRun'] = 'All'
+            kwargs['params'] = params
         return kwargs
 
     def raise_for_status(self, resp):

tests/test_http.py

@@ -34,6 +34,22 @@ def test_http(monkeypatch):
     assert mock_send.call_args[1]['timeout'] == DEFAULT_HTTP_TIMEOUT
 
 
+def test_http_with_dry_run(monkeypatch):
+    cfg = KubeConfig.from_file(GOOD_CONFIG_FILE_PATH)
+    api = HTTPClient(cfg, dry_run=True)
+
+    mock_send = MagicMock()
+    mock_send.side_effect = Exception('MOCK HTTP')
+    monkeypatch.setattr('pykube.http.KubernetesHTTPAdapter._do_send', mock_send)
+
+    with pytest.raises(Exception):
+        api.get(url='test')
+
+    mock_send.assert_called_once()
+    # check that dry run http parameters were set
+    assert mock_send.call_args[0][0].url == "http://localhost/api/v1/test?dryRun=All"
+
+
 def test_http_insecure_skip_tls_verify(monkeypatch):
     cfg = KubeConfig.from_file(CONFIG_WITH_INSECURE_SKIP_TLS_VERIFY)
     api = HTTPClient(cfg)