packages: use DataDir to load mappings

This simplifies the code, removing the usage of pkg_resources.  There is
no command line interface change yet; the data directory is *not* used
to allow local mappings, as the file is always marked as internal.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

2 files changed, 16 insertions, 12 deletions

diff --git a/lcitool/packages.py b/lcitool/packages.py
index 6f3c313..efa7319 100644
--- a/lcitool/packages.py
+++ b/lcitool/packages.py
@@ -39,9 +39,6 @@ Exported functions:
 
 import abc
 import logging
-import yaml
-
-from pkg_resources import resource_filename
 
 from lcitool import util, LcitoolError
 
@@ -203,7 +200,8 @@ class Packages:
 
     """
 
-    def __init__(self):
+    def __init__(self, data_dir=util.DataDir()):
+        self._data_dir = data_dir
         self._mappings = None
         self._pypi_mappings = None
         self._cpan_mappings = None
@@ -316,15 +314,11 @@ class Packages:
             return self._get_cross_package(pkg_mapping, target)
 
     def _load_mappings(self):
-        mappings_path = resource_filename(__name__,
-                                          "facts/mappings.yml")
-
         try:
-            with open(mappings_path, "r") as infile:
-                mappings = yaml.safe_load(infile)
-                self._mappings = mappings["mappings"]
-                self._pypi_mappings = mappings["pypi_mappings"]
-                self._cpan_mappings = mappings["cpan_mappings"]
+            mappings = self._data_dir.load_yaml("facts", "mappings")
+            self._mappings = mappings["mappings"]
+            self._pypi_mappings = mappings["pypi_mappings"]
+            self._cpan_mappings = mappings["cpan_mappings"]
         except Exception as ex:
             log.debug("Can't load mappings")
             raise PackageError(f"Can't load mappings: {ex}")
diff --git a/lcitool/util.py b/lcitool/util.py
index 4fb65a1..56a6831 100644
--- a/lcitool/util.py
+++ b/lcitool/util.py
@@ -11,6 +11,7 @@ import os
 import platform
 import tempfile
 import textwrap
+import yaml
 
 from pathlib import Path
 from pkg_resources import resource_filename
@@ -252,6 +253,15 @@ class DataDir:
                 if file.is_file() and (suffix is None or file.suffix == suffix):
                     yield file
 
+    def load_yaml(self, resource_path, name):
+        file = Path(resource_filename(__name__, resource_path), name + ".yml")
+        if not file.exists():
+            return {}
+
+        log.debug(f"Loading facts from '{file}'")
+        with open(file, "r") as infile:
+            return yaml.safe_load(infile)
+
 
 def validate_cross_platform(cross_arch, osname):
     if osname not in ["Debian", "Fedora"]: