Split retrieval of deps into a separate function.

repos/system_upgrade/common/libraries/rpms.py

@@ -156,37 +156,83 @@ def check_file_modification(config):
     return _parse_config_modification(output, config)
 
 
-def get_leapp_packages(major_version=None, component=_LEAPP_DEFAULT_COMPONENTS, include_deps=False):
+def _get_leapp_packages_of_type(major_version, component, type_='pkgs'):
     """
-    Get list of leapp packages.
+    Private implementation of get_leapp_packages() and get_leapp_deps_packages().
 
-    :param major_version: a list or string specifying major_versions. If not defined then current
-        system_version will be used.
-    :param component: a list or a single enum value specifying leapp components
-        (use enum :class: LeappComponents) If defined then only packages related to the specific
-        component(s) will be returned.
-    :param include_deps: a flag to control whether deps meta packages are to be included.
-    :raises ValueError: if a requested component or major_version doesn't exist.
+    :param major_version: Same as for :func:`get_leapp_packages` and
+        :func:`get_leapp_deps_packages`
+    :param component: Same as for :func:`get_leapp_packages` and :func:`get_leapp_deps_packages`
+    :param type_: Either "pkgs" or "deps".  Determines which set of packages we're looking for.
+        Corresponds to the keys in the `_LEAPP_PACKAGES_MAP`.
+
+    Retrieving the set of leapp and leapp-deps packages only differs in which key is used to
+    retrieve the packages from _LEAPP_PACKAGES_MAP.  This function abstracts that difference.
     """
     res = set()
+
     major_versions = [major_version] if isinstance(major_version, str) else major_version
     if not major_versions:
         # No major_version of interest specified -> treat as if only current source system version
         # requested
         major_versions = [get_source_major_version()]
+
     components = [component] if isinstance(component, str) else component
+    if not components:
+        error_msg = ("At least one component must be specified when calling this"
+                     " function, available choices are {choices}".format(
+                         choices=sorted(_LEAPP_PACKAGES_MAP.keys()))
+                     )
+        raise ValueError(error_msg)
+
     for comp in components:
         for a_major_version in major_versions:
             if comp not in _LEAPP_PACKAGES_MAP:
                 error_msg = "The requested component {comp} is unknown, available choices are {choices}".format(
                         comp=component, choices=sorted(_LEAPP_PACKAGES_MAP.keys()))
                 raise ValueError(error_msg)
+
             if a_major_version not in _LEAPP_PACKAGES_MAP[comp]:
                 error_msg = "The requested major_version {ver} is unknown, available choices are {choices}".format(
                         ver=a_major_version, choices=sorted(_LEAPP_PACKAGES_MAP[comp].keys()))
                 raise ValueError(error_msg)
+
             # All went well otherwise, get the data
-            res.update(_LEAPP_PACKAGES_MAP[comp][a_major_version].get('pkgs', []))
-            if include_deps:
-                res.update(_LEAPP_PACKAGES_MAP[comp][a_major_version].get('deps', []))
+            res.update(_LEAPP_PACKAGES_MAP[comp][a_major_version].get(type_, []))
+
     return sorted(res)
+
+
+def get_leapp_packages(major_version=None, component=_LEAPP_DEFAULT_COMPONENTS):
+    """
+    Get list of leapp packages.
+
+    :param major_version: a list or string specifying major_versions. If not defined then current
+        system_version will be used.
+    :param component: a list or a single enum value specifying leapp components
+        (use enum :class: LeappComponents) If defined then only packages related to the specific
+        component(s) will be returned.
+    :raises ValueError: if a requested component or major_version doesn't exist.
+
+    .. note::
+        Call :func:`get_leapp_dep_packages` as well if you also need the deps metapackages.
+        Those packages determine which RPMs need to be installed for leapp to function.
+        They aren't just Requires on the base leapp and leapp-repository RPMs because they
+        need to be switched from the old system_version's to the new ones at a different
+        point in the upgrade than the base RPMs.
+    """
+    return _get_leapp_packages_of_type(major_version, component, type_="pkgs")
+
+
+def get_leapp_dep_packages(major_version=None, component=_LEAPP_DEFAULT_COMPONENTS):
+    """
+    Get list of leapp dep metapackages.
+
+    :param major_version: a list or string specifying major_versions. If not defined then current
+        system_version will be used.
+    :param component: a list or a single enum value specifying leapp components
+        (use enum :class: LeappComponents) If defined then only packages related to the specific
+        component(s) will be returned.
+    :raises ValueError: if a requested component or major_version doesn't exist.
+    """
+    return _get_leapp_packages_of_type(major_version, component, type_="deps")