feat: search current working directory for config file (#1464)

Resolves #1333 

Adds the current working directory to the search path for the
`.pyiceberg.yaml` file.

As it is now, the file is searched in the following order:
1. the `PYICEBERG_HOME` environment variable
2. ~/
3. ./

I'm unsure if people would like to have 2 and 3 swapped. In either case,
users can still override this with the environment variable.

---------

Co-authored-by: Fokko Driesprong <[email protected]>
Co-authored-by: Kevin Liu <[email protected]>

Author: 3 people

mkdocs/docs/api.md

@@ -49,7 +49,7 @@ catalog:
 
 and loaded in python by calling `load_catalog(name="hive")` and `load_catalog(name="rest")`.
 
-This information must be placed inside a file called `.pyiceberg.yaml` located either in the `$HOME` or `%USERPROFILE%` directory (depending on whether the operating system is Unix-based or Windows-based, respectively) or in the `$PYICEBERG_HOME` directory (if the corresponding environment variable is set).
+This information must be placed inside a file called `.pyiceberg.yaml` located either in the `$HOME` or `%USERPROFILE%` directory (depending on whether the operating system is Unix-based or Windows-based, respectively), in the current working directory, or in the `$PYICEBERG_HOME` directory (if the corresponding environment variable is set).
 
 For more details on possible configurations refer to the [specific page](https://py.iceberg.apache.org/configuration/).
 

mkdocs/docs/configuration.md

@@ -28,11 +28,11 @@ hide:
 
 There are three ways to pass in configuration:
 
-- Using the `~/.pyiceberg.yaml` configuration file
+- Using the `.pyiceberg.yaml` configuration file (Recommended)
 - Through environment variables
 - By passing in credentials through the CLI or the Python API
 
-The configuration file is recommended since that's the easiest way to manage the credentials.
+The configuration file can be stored in either the directory specified by the `PYICEBERG_HOME` environment variable, the home directory, or current working directory (in this order).
 
 To change the path searched for the `.pyiceberg.yaml`, you can overwrite the `PYICEBERG_HOME` environment variable.
 

pyiceberg/utils/config.py

@@ -84,12 +84,14 @@ def _load_yaml(directory: Optional[str]) -> Optional[RecursiveDict]:
                     return file_config_lowercase
             return None
 
-        # Give priority to the PYICEBERG_HOME directory
-        if pyiceberg_home_config := _load_yaml(os.environ.get(PYICEBERG_HOME)):
-            return pyiceberg_home_config
-        # Look into the home directory
-        if pyiceberg_home_config := _load_yaml(os.path.expanduser("~")):
-            return pyiceberg_home_config
+        # Directories to search for the configuration file
+        # The current search order is: PYICEBERG_HOME, home directory, then current directory
+        search_dirs = [os.environ.get(PYICEBERG_HOME), os.path.expanduser("~"), os.getcwd()]
+
+        for directory in search_dirs:
+            if config := _load_yaml(directory):
+                return config
+
         # Didn't find a config
         return None
 

tests/utils/test_config.py

@@ -15,6 +15,7 @@
 # specific language governing permissions and limitations
 # under the License.
 import os
+from typing import Any, Dict, Optional
 from unittest import mock
 
 import pytest
@@ -93,3 +94,84 @@ def test_from_configuration_files_get_typed_value(tmp_path_factory: pytest.TempP
 
     assert Config().get_bool("legacy-current-snapshot-id")
     assert Config().get_int("max-workers") == 4
+
+
+@pytest.mark.parametrize(
+    "config_setup, expected_result",
+    [
+        # PYICEBERG_HOME takes precedence
+        (
+            {
+                "pyiceberg_home_content": "https://service.io/pyiceberg_home",
+                "home_content": "https://service.io/user-home",
+                "cwd_content": "https://service.io/cwd",
+            },
+            "https://service.io/pyiceberg_home",
+        ),
+        # Home directory (~) is checked after PYICEBERG_HOME
+        (
+            {
+                "pyiceberg_home_content": None,
+                "home_content": "https://service.io/user-home",
+                "cwd_content": "https://service.io/cwd",
+            },
+            "https://service.io/user-home",
+        ),
+        # Current working directory (.) is the last fallback
+        (
+            {
+                "pyiceberg_home_content": None,
+                "home_content": None,
+                "cwd_content": "https://service.io/cwd",
+            },
+            "https://service.io/cwd",
+        ),
+        # No configuration files found
+        (
+            {
+                "pyiceberg_home_content": None,
+                "home_content": None,
+                "cwd_content": None,
+            },
+            None,
+        ),
+    ],
+)
+def test_config_lookup_order(
+    monkeypatch: pytest.MonkeyPatch,
+    tmp_path_factory: pytest.TempPathFactory,
+    config_setup: Dict[str, Any],
+    expected_result: Optional[str],
+) -> None:
+    """
+    Test that the configuration lookup prioritizes PYICEBERG_HOME, then home (~), then cwd.
+    """
+
+    def create_config_file(path: str, uri: Optional[str]) -> None:
+        if uri:
+            config_file_path = os.path.join(path, ".pyiceberg.yaml")
+            content = {"catalog": {"default": {"uri": uri}}}
+            with open(config_file_path, "w", encoding="utf-8") as file:
+                yaml_str = as_document(content).as_yaml()
+                file.write(yaml_str)
+
+    # Create temporary directories for PYICEBERG_HOME, home (~), and cwd
+    pyiceberg_home = str(tmp_path_factory.mktemp("pyiceberg_home"))
+    home_dir = str(tmp_path_factory.mktemp("home"))
+    cwd_dir = str(tmp_path_factory.mktemp("cwd"))
+
+    # Create configuration files in the respective directories
+    create_config_file(pyiceberg_home, config_setup.get("pyiceberg_home_content"))
+    create_config_file(home_dir, config_setup.get("home_content"))
+    create_config_file(cwd_dir, config_setup.get("cwd_content"))
+
+    # Mock environment and paths
+    monkeypatch.setenv("PYICEBERG_HOME", pyiceberg_home)
+    monkeypatch.setattr(os.path, "expanduser", lambda _: home_dir)
+    monkeypatch.chdir(cwd_dir)
+
+    # Perform the lookup and validate the result
+    result = Config()._from_configuration_files()
+    assert (
+        result["catalog"]["default"]["uri"] if result else None  # type: ignore
+    ) == expected_result, f"Unexpected configuration result. Expected: {expected_result}, Actual: {result}"