ELN: Generate gather_source on-the-fly before each compose.

Signed-off-by: Jan Kaluza <jkaluza@redhat.com>

fedora/override.conf

@@ -97,7 +97,16 @@ variant_as_lookaside = [
 
 # TODO: There is no "fus" in Fedora and no comps yet. For now use "json"
 # source and "deps" method.
-gather_source_mapping = "gather_source.json"
+# Generate gather_source.json on-the-fly using the prepopulate scm dict,
+# store it into /srv/odcs and use it from there.
+gather_prepopulate = {
+    'scm': 'git',
+    'repo': "https://pagure.io/pungi-fedora.git",
+    'branch': "eln",
+    'file': "prepopulate.json",
+    'command': "echo {} > prepopulate.json; ./content-resolver-to-gather-source-json; cp gather_source.json /srv/odcs"
+}
+gather_source_mapping = "/srv/odcs/gather_source.json"
 gather_method = "deps"
 
 # No product_id for Fedora.