kojiwrapper: Stop being smart about local access

Rather than trying to use local access when it's accessible, let user
make the decision:

 * if koji_cache is configured use it and download stuff
 * if not, fall back to local access

Signed-off-by: Lubomír Sedlář <lsedlar@redhat.com>

pungi/phases/pkgset/sources/source_koji.py

@@ -194,7 +194,7 @@ class PkgsetSourceKoji(pungi.phases.pkgset.source.PkgsetSourceBase):
         compose = self.compose
         self.koji_wrapper = pungi.wrappers.kojiwrapper.KojiWrapper(compose)
         package_sets = get_pkgset_from_koji(self.compose, self.koji_wrapper)
-        return (package_sets, self.compose.koji_downloader.cache_dir)
+        return (package_sets, self.compose.koji_downloader.path_prefix)
 
 
 def get_pkgset_from_koji(compose, koji_wrapper):
@@ -920,7 +920,7 @@ def populate_global_pkgset(compose, koji_wrapper, event):
                 MaterializedPackageSet.create,
                 compose,
                 pkgset,
-                compose.koji_downloader.cache_dir,
+                compose.koji_downloader.path_prefix,
                 mmd=tag_to_mmd.get(pkgset.name),
             )
         )

pungi/wrappers/kojiwrapper.py

@@ -905,6 +905,12 @@ def get_buildroot_rpms(compose, task_id):
 class KojiDownloadProxy:
     def __init__(self, topdir, topurl, cache_dir, logger):
         if not topdir:
+            # This will only happen if there is either no koji_profile
+            # configured, or the profile doesn't have a topdir. In the first
+            # case there will be no koji interaction, and the second indicates
+            # broken koji configuration.
+            # We can pretend to have local access in both cases to avoid any
+            # external requests.
             self.has_local_access = True
             return
 
@@ -914,7 +920,9 @@ class KojiDownloadProxy:
         self.topdir = topdir
         self.topurl = topurl
 
-        self.has_local_access = os.path.isdir(self.topdir)
+        # If cache directory is configured, we want to use it (even if we
+        # actually have local access to the storage).
+        self.has_local_access = not bool(cache_dir)
         # This is used for temporary downloaded files. The suffix is unique
         # per-process. To prevent threads in the same process from colliding, a
         # thread id is added later.
@@ -923,20 +931,25 @@ class KojiDownloadProxy:
         if not self.has_local_access:
             self.session = requests.Session()
 
+    @property
+    def path_prefix(self):
+        dir = self.topdir if self.has_local_access else self.cache_dir
+        return dir.rstrip("/") + "/"
+
     @classmethod
     def from_config(klass, conf, logger):
         topdir = None
         topurl = None
-        path_prefix = None
+        cache_dir = None
         if "koji_profile" in conf:
             koji_module = koji.get_profile_module(conf["koji_profile"])
             topdir = koji_module.config.topdir
             topurl = koji_module.config.topurl
 
-            path_prefix = topdir.rstrip("/") + "/"
-            if not os.path.exists(path_prefix):
-                path_prefix = conf["koji_cache"].rstrip("/") + "/"
-        return klass(topdir, topurl, path_prefix, logger)
+            cache_dir = conf.get("koji_cache")
+            if cache_dir:
+                cache_dir = cache_dir.rstrip("/") + "/"
+        return klass(topdir, topurl, cache_dir, logger)
 
     @util.retry(wait_on=requests.exceptions.RequestException)
     def _download(self, url, dest):

tests/helpers.py

@@ -256,7 +256,7 @@ class DummyCompose(object):
         self.containers_metadata = {}
         self.load_old_compose_config = mock.Mock(return_value=None)
         self.koji_downloader = DummyKojiDownloader()
-        self.koji_downloader.cache_dir = "/prefix"
+        self.koji_downloader.path_prefix = "/prefix"
 
     def setup_optional(self):
         self.all_variants["Server-optional"] = MockVariant(