Add fdb_home argument to constructor

pyproject.toml

@@ -25,7 +25,7 @@ urls.Homepage = "https://github.com/ecmwf/pyfdb"
 urls.Issues = "https://github.com/ecmwf/pyfdb/issues"
 urls.Repository = "https://github.com/ecmwf/pyfdb"
 
-requires-python = ">=3.9"
+requires-python = ">=3.8"
 
 dependencies = [
   "cffi",

src/pyfdb/pyfdb.py

@@ -16,6 +16,8 @@
 import json
 import os
 from functools import wraps
+from pathlib import Path
+from typing import Optional, Union
 
 import cffi
 import findlibs
@@ -290,15 +292,48 @@ class FDB:
         fdb = pyfdb.FDB()
         # call fdb.archive, fdb.list, fdb.retrieve, fdb.flush as needed.
 
+        # Construct with a particular FDB_HOME
+        fdb = pyfdb.FDB(fdb_home="/path/to/fdb_home")
+
+        # Construct from a config dictionary
+        config = dict(
+            type="local",
+            engine="toc",
+            schema="path/to/schema",
+            spaces=[
+                dict(
+                    handler="Default",
+                    roots=[
+                        {"path": "/path/to/root"},
+                    ],
+                )
+            ],
+        )
+        fdb = pyfdb.FDB(config)
+
     See the module level pyfdb.list, pyfdb.retrieve, and pyfdb.archive
     docstrings for more information on these functions.
     """
 
     __fdb = None
 
-    def __init__(self, config=None, user_config=None):
+    def __init__(
+        self,
+        config: Optional[dict] = None,
+        user_config: Optional[dict] = None,
+        fdb_home: Union[str, Path, None] = None,
+    ):
+        """
+        Args:
+        """
         fdb = ffi.new("fdb_handle_t**")
 
+        if fdb_home is not None and config is not None:
+            raise ValueError("Cannot specify both fdb_home and config")
+
+        if fdb_home is not None:
+            config = dict(fdb_home=str(fdb_home))
+
         if config is not None or user_config is not None:
 
             def prepare_config(c):

tests/test_passing_config_directly.py

@@ -1,11 +1,74 @@
+import os
+import shutil
 from pathlib import Path
 from tempfile import TemporaryDirectory
 
+from pytest import raises
+
 import pyfdb
 
+IS_ATOS = os.environ.get("SCRATCHDIR", None)
+
+
+def test_conflicting_arguments():
+    "You can't pass both fdb_home and config because the former overrides the latter!"
+    assert raises(ValueError, pyfdb.FDB, fdb_home="/tmp", config={})
+
+
+def test_fdb_home():
+    with TemporaryDirectory(dir=IS_ATOS) as tmp_home:
+        tests_dir = Path(__file__).parent
+        schema_path = tests_dir / "default_fdb_schema"
+
+        home = Path(tmp_home)
+        etc = home / "etc" / "fdb"
+        root_path = home / "root"
+        root_path.mkdir(parents=True)
+        etc.mkdir(parents=True)
+
+        shutil.copy(schema_path, etc / "schema")
+
+        with open(etc / "config.yaml", "w") as f:
+            f.write(
+                f"""
+---
+type: local
+engine: toc
+schema: {etc / "schema"}
+spaces:
+- handler: Default
+  roots:
+    - path: "{root_path}"
+      writable: true
+      visit: true
+"""
+            )
+
+        with open(etc / "config.yaml", "r") as f:
+            print(f.read())
+
+        fdb = pyfdb.FDB(fdb_home=home)
+        data = open(tests_dir / "x138-300.grib", "rb").read()
+        fdb.archive(data)
+        fdb.flush()
+
+        list_output = list(fdb.list(keys=True))
+        assert len(list_output) == 1
+
+        # Check that the archive path is in the tmp directory
+        # On OSX tmp file paths look like /private/var/folders/.../T/tmp.../x138-300.grib
+        # While the tmp directory looks like /var/folders/.../T/tmp.../ hence why this check is not "startwith"
+
+        # Disabled for now because the HPC has a different convention and I don't know how to deal with all cases
+        # On the HPC
+        # tmp_home looks like '/etc/ecmwf/ssd/ssd1/tmpdirs/***.31103395/tmpg137a4ml'
+        # while the archive path looks like '/etc/ecmwf/ssd/ssd1/tmpdirs/***.31103395/data/fdb/...'
+
+        assert os.path.realpath(tmp_home) in os.path.realpath(list_output[0]["path"])
+
 
 def test_direct_config():
-    with TemporaryDirectory() as tmp_root:
+    with TemporaryDirectory(dir=IS_ATOS) as tmp_root:
         tests_dir = Path(__file__).parent
 
         config = dict(
@@ -33,11 +96,13 @@ def test_direct_config():
         # Check that the archive path is in the tmp directory
         # On OSX tmp file paths look like /private/var/folders/.../T/tmp.../x138-300.grib
         # While the tmp directory looks like /var/folders/.../T/tmp.../ hence why this check is not "startwith"
-        assert tmp_root in list_output[0]["path"]
+
+        # Disabled for now because the HPC has a different convention and I don't know how to deal with all cases
+        assert os.path.realpath(tmp_root) in os.path.realpath(list_output[0]["path"])
 
 
 def test_opening_two_fdbs():
-    with TemporaryDirectory() as tmp_root1, TemporaryDirectory() as tmp_root2:
+    with TemporaryDirectory(dir=IS_ATOS) as tmp_root1, TemporaryDirectory(dir=IS_ATOS) as tmp_root2:
         tests_dir = Path(__file__).parent
 
         fdb1 = pyfdb.FDB(
@@ -80,4 +145,4 @@ def test_opening_two_fdbs():
         for fdb, root in [(fdb1, tmp_root1), (fdb2, tmp_root2)]:
             list_output = list(fdb.list(keys=True))
             assert len(list_output) == 1
-            assert root in list_output[0]["path"]
+            assert os.path.realpath(root) in os.path.realpath(list_output[0]["path"])

tox.ini

@@ -19,6 +19,10 @@ wheel_build_env = .pkg
 deps =
     pytest>=6
 pass_env =
-    FDB_HOME
+    FDB_HOME # (optional) Tells fdb where to look for config files
+    FDB5_HOME # (optional) Tell findlibs where to find lib/libfdb5.dylib
+    ECCODES_HOME # (optional) Tell findlibs where to find lib/libeccodes.dylib
+    ECCODES_PYTHON_TRACE_LIB_SEARCH # (optional) Print debug info about eccodes search for libeccodes.dylib
+    ECCODES_PYTHON_USE_FINDLIBS # (optional) Force eccodes to use findlibs to find libeccodes.dylib rather that using the binary installed by pip
 commands =
     pytest {tty:--color=yes} {posargs}