__init__ takes service name and dict

Moving service name and dict out of the function make_service_dict
and into __init__. We always call make_service_dict with those so
let's put them in the initialiser. Slightly cleaner design intent.

The whole purpose of the ServiceLoader is to take a
service name&service dictionary then validate, process and return
service dictionaries ready to be created.

This is also another step towards cleaning the code up so we can
interpolate and validate an extended dictionary.

Signed-off-by: Mazz Mosley <mazz@houseofmnowster.com>

compose/config/config.py

@@ -142,8 +142,12 @@ def load(config_details):
     service_dicts = []
 
     for service_name, service_dict in list(processed_config.items()):
-        loader = ServiceLoader(working_dir=working_dir, filename=filename)
-        service_dict = loader.make_service_dict(service_name, service_dict)
+        loader = ServiceLoader(
+            working_dir=working_dir,
+            filename=filename,
+            service_name=service_name,
+            service_dict=service_dict)
+        service_dict = loader.make_service_dict()
         validate_paths(service_dict)
         service_dicts.append(service_dict)
 
@@ -151,7 +155,7 @@ def load(config_details):
 
 
 class ServiceLoader(object):
-    def __init__(self, working_dir, filename, already_seen=None):
+    def __init__(self, working_dir, filename, service_name, service_dict, already_seen=None):
         if working_dir is None:
             raise Exception("No working_dir passed to ServiceLoader()")
 
@@ -162,17 +166,19 @@ class ServiceLoader(object):
         else:
             self.filename = filename
         self.already_seen = already_seen or []
+        self.service_dict = service_dict.copy()
+        self.service_dict['name'] = service_name
 
     def detect_cycle(self, name):
         if self.signature(name) in self.already_seen:
             raise CircularReference(self.already_seen + [self.signature(name)])
 
-    def make_service_dict(self, name, service_dict):
-        service_dict = service_dict.copy()
-        service_dict['name'] = name
-        service_dict = resolve_environment(service_dict, working_dir=self.working_dir)
-        service_dict = self.resolve_extends(service_dict)
-        return process_container_options(service_dict, working_dir=self.working_dir)
+    def make_service_dict(self):
+        # service_dict = service_dict.copy()
+        # service_dict['name'] = name
+        self.service_dict = resolve_environment(self.service_dict, working_dir=self.working_dir)
+        self.service_dict = self.resolve_extends(self.service_dict)
+        return process_container_options(self.service_dict, working_dir=self.working_dir)
 
     def resolve_extends(self, service_dict):
         if 'extends' not in service_dict:
@@ -188,11 +194,6 @@ class ServiceLoader(object):
 
         other_working_dir = os.path.dirname(other_config_path)
         other_already_seen = self.already_seen + [self.signature(service_dict['name'])]
-        other_loader = ServiceLoader(
-            working_dir=other_working_dir,
-            filename=other_config_path,
-            already_seen=other_already_seen,
-        )
 
         base_service = extends_options['service']
         other_config = load_yaml(other_config_path)
@@ -204,11 +205,16 @@ class ServiceLoader(object):
             raise ConfigurationError(msg)
 
         other_service_dict = other_config[base_service]
-        other_loader.detect_cycle(extends_options['service'])
-        other_service_dict = other_loader.make_service_dict(
-            service_dict['name'],
-            other_service_dict,
+        other_loader = ServiceLoader(
+            working_dir=other_working_dir,
+            filename=other_config_path,
+            service_name=service_dict['name'],
+            service_dict=other_service_dict,
+            already_seen=other_already_seen,
         )
+
+        other_loader.detect_cycle(extends_options['service'])
+        other_service_dict = other_loader.make_service_dict()
         validate_extended_service_dict(
             other_service_dict,
             filename=other_config_path,

tests/integration/testcases.py

@@ -31,7 +31,7 @@ class DockerClientTestCase(unittest.TestCase):
         if 'command' not in kwargs:
             kwargs['command'] = ["top"]
 
-        options = ServiceLoader(working_dir='.', filename=None).make_service_dict(name, kwargs)
+        options = ServiceLoader(working_dir='.', filename=None, service_name=name, service_dict=kwargs).make_service_dict()
 
         labels = options.setdefault('labels', {})
         labels['com.docker.compose.test-name'] = self.id()

tests/unit/config_test.py

@@ -15,7 +15,11 @@ def make_service_dict(name, service_dict, working_dir, filename=None):
     """
     Test helper function to construct a ServiceLoader
     """
-    return config.ServiceLoader(working_dir=working_dir, filename=filename).make_service_dict(name, service_dict)
+    return config.ServiceLoader(
+        working_dir=working_dir,
+        filename=filename,
+        service_name=name,
+        service_dict=service_dict).make_service_dict()
 
 
 def service_sort(services):