Issue #324 support simple str/path as file in DataCube.print_json

openeo/internal/compat.py

@@ -0,0 +1,13 @@
+"""
+Compatibility layer and small backports.
+"""
+
+import contextlib
+
+try:
+    from contextlib import nullcontext
+except ImportError:
+    # nullcontext for pre-3.7 python
+    @contextlib.contextmanager
+    def nullcontext(enter_result=None):
+        yield enter_result

openeo/rest/_datacube.py

@@ -1,8 +1,11 @@
 import json
 import logging
+import sys
 import typing
+from pathlib import Path
 from typing import Optional, Union, Tuple
 
+from openeo.internal.compat import nullcontext
 from openeo.internal.graph_building import PGNode, _FromNodeMixin
 from openeo.util import legacy_alias
 
@@ -71,12 +74,23 @@ def print_json(self, *, file=None, indent: Union[int, None] = 2, separators: Opt
         Also see ``json.dumps`` docs for more information on the JSON formatting options.
 
         :param file: file-like object (stream) to print to (current ``sys.stdout`` by default).
+            Or a path (string or pathlib.Path) to a file to write to.
         :param indent: JSON indentation level.
         :param separators: (optional) tuple of item/key separators.
 
         .. versionadded:: 0.12.0
         """
-        print(self.to_json(indent=indent, separators=separators), file=file)
+        pg = {"process_graph": self.flat_graph()}
+        if isinstance(file, (str, Path)):
+            # Create (new) file and automatically close it
+            file_ctx = Path(file).open("w", encoding="utf8")
+        else:
+            # Just use file as-is, but don't close it automatically.
+            file_ctx = nullcontext(enter_result=file or sys.stdout)
+        with file_ctx as f:
+            json.dump(pg, f, indent=indent, separators=separators)
+            if indent is not None:
+                f.write("\n")
 
     @property
     def _api_version(self):

tests/rest/datacube/test_datacube100.py

@@ -1470,6 +1470,16 @@ def test_print_json_file(con100):
     assert f.getvalue() == EXPECTED_JSON_EXPORT_S2_NDVI + "\n"
 
 
+@pytest.mark.parametrize("path_factory", [str, pathlib.Path])
+def test_print_json_file_path(con100, tmp_path, path_factory):
+    ndvi = con100.load_collection("S2").ndvi()
+    path = tmp_path / "dump.json"
+    assert not path.exists()
+    ndvi.print_json(file=path_factory(path))
+    assert path.exists()
+    assert path.read_text() == EXPECTED_JSON_EXPORT_S2_NDVI + "\n"
+
+
 def test_sar_backscatter_defaults(con100):
     cube = con100.load_collection("S2").sar_backscatter()
     assert _get_leaf_node(cube) == {