New-style PDC deps.

This is only one half of the modulemd-1.0 changes needed around PDC.

This was done to get module handling their dependencies when they are
defined in terms of streams instead of NVRs.

In PDC we used to store the dep as one whole string, i.e.::

    base-runtime-0.25-11

Now we're going to store them with some more structure, since we can't
assume monotonically increasing version values::

    dependency: base-runtime
    stream: master

Pull-requests to PDC and PDC-updater are forthcoming.

module_build_service/pdc.py

@@ -28,6 +28,7 @@
 import modulemd
 from pdc_client import PDCClient
 
+import pprint
 import logging
 log = logging.getLogger()
 
@@ -64,7 +65,7 @@ def get_variant_dict(data):
         if not isinstance(data, dict):
             return False
 
-        for attr in ('variant_id', 'variant_version', 'variant_release'):
+        for attr in ('variant_id', 'variant_stream'):
             if attr not in data.keys():
                 return False
         return True
@@ -84,13 +85,17 @@ def get_variant_dict(data):
         result = {'variant_id': data.name, 'variant_version': data.version, 'variant_release': data.release }
 
     elif is_variant_dict(data):
-        result = data
+        result = data.copy()
+
+        # This is a transitionary thing until we've ported PDC away from the old nomenclature
+        if 'variant_version' not in result and 'variant_stream' in result:
+            result['variant_version'] = result['variant_stream']
+            del result['variant_stream']
+
         # ensure that variant_type is in result
         if 'variant_type' not in result.keys():
             result['variant_type'] = 'module'
 
-        if 'variant_release' not in result.keys():
-            result['variant_release'] = '0'
 
     elif is_module_dict(data):
         result = {'variant_id': data['name'], 'variant_version': data['version'], 'variant_release': data['release']}
@@ -132,16 +137,21 @@ def get_module(session, module_info, strict=False):
     """
 
     module_info = get_variant_dict(module_info)
-    retval = session['unreleasedvariants'](page_size=-1,
-                variant_id=module_info['variant_id'],
-                variant_version=module_info['variant_version'],
-                variant_release=module_info['variant_release'])
-    assert len(retval) <= 1
+
+    query = dict(
+        variant_id=module_info['variant_id'],
+        variant_version=module_info['variant_version'],
+    )
+    if module_info.get('variant_release'):
+        query['variant_release'] = module_info['variant_release']
+
+    retval = session['unreleasedvariants'](page_size=-1, **query) # ordering=variant_release...
+    assert len(retval) <= 1, pprint.pformat(retval)
 
     # Error handling
     if not retval:
         if strict:
-            raise ValueError("Failed to find module in PDC %r" % module_info)
+            raise ValueError("Failed to find module in PDC %r" % query)
         else:
             return None
 
@@ -202,7 +212,8 @@ def get_module_runtime_dependencies(session, module_info, strict=False):
     deps = []
     module_info = get_module(session, module_info, strict=strict)
     if module_info and module_info.get('runtime_deps', None):
-        deps = [x['dependency'] for x in module_info['runtime_deps']]
+        deps = [dict(variant_id=x['dependency'], variant_stream=x['stream'])
+                for x in module_info['runtime_deps']]
         deps = module_depsolving_wrapper(session, deps, strict=strict)
 
     return deps
@@ -222,7 +233,8 @@ def get_module_build_dependencies(session, module_info, strict=False):
     deps = []
     module_info = get_module(session, module_info, strict=strict)
     if module_info and module_info.get('build_deps', None):
-        deps = [x['dependency'] for x in module_info['build_deps']]
+        deps = [dict(variant_id=x['dependency'], variant_stream=x['stream'])
+                for x in module_info['build_deps']]
         deps = module_depsolving_wrapper(session, deps, strict=strict)
 
     return deps