api: reorganize policy generation API (#196)

Extract policy generation API from api's __init__.py and move into
verb as nothing else uses it.

Signed-off-by: Kyle Fazzari <[email protected]>

sros2/sros2/api/__init__.py

@@ -12,53 +12,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from collections import namedtuple
-
-HIDDEN_NODE_PREFIX = '_'
-
-NodeName = namedtuple('NodeName', ('node', 'ns', 'fqn'))
-TopicInfo = namedtuple('Topic', ('fqn', 'type'))
-
-
-def get_node_names(*, node, include_hidden_nodes=False):
-    node_names_and_namespaces = node.get_node_names_and_namespaces()
-    return [
-        NodeName(
-            node=t[0],
-            ns=t[1],
-            fqn=t[1] + ('' if t[1].endswith('/') else '/') + t[0])
-        for t in node_names_and_namespaces
-        if (
-            include_hidden_nodes or
-            (t[0] and not t[0].startswith(HIDDEN_NODE_PREFIX))
-        )
-    ]
-
-
-def get_topics(node_name, func):
-    names_and_types = func(node_name.node, node_name.ns)
-    return [
-        TopicInfo(
-            fqn=t[0],
-            type=t[1])
-        for t in names_and_types]
-
-
-def get_subscriber_info(node, node_name):
-    return get_topics(node_name, node.get_subscriber_names_and_types_by_node)
-
-
-def get_publisher_info(node, node_name):
-    return get_topics(node_name, node.get_publisher_names_and_types_by_node)
-
-
-def get_service_info(node, node_name):
-    return get_topics(node_name, node.get_service_names_and_types_by_node)
-
-
-def get_client_info(node, node_name):
-    return get_topics(node_name, node.get_client_names_and_types_by_node)
-
 
 def distribute_key(source_keystore_path, taget_keystore_path):
     raise NotImplementedError()

sros2/sros2/verb/generate_policy.py

@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from collections import namedtuple
 import os
 import sys
 
@@ -31,14 +32,6 @@ def FilesCompleter(*, allowednames, directories):
 from ros2cli.node.strategy import add_arguments as add_strategy_node_arguments
 from ros2cli.node.strategy import NodeStrategy
 
-from sros2.api import (
-    get_client_info,
-    get_node_names,
-    get_publisher_info,
-    get_service_info,
-    get_subscriber_info
-)
-
 from sros2.policy import (
     dump_policy,
     load_policy,
@@ -48,6 +41,12 @@ def FilesCompleter(*, allowednames, directories):
 from sros2.verb import VerbExtension
 
 
+_HIDDEN_NODE_PREFIX = '_'
+
+_NodeName = namedtuple('NodeName', ('node', 'ns', 'fqn'))
+_TopicInfo = namedtuple('Topic', ('fqn', 'type'))
+
+
 def formatTopics(topic_list, permission, topic_map):
     for topic in topic_list:
         topic_map[topic.name].append(permission)
@@ -116,7 +115,7 @@ def add_permission(
     def main(self, *, args):
         policy = self.get_policy(args.POLICY_FILE_PATH)
         with NodeStrategy(args) as node:
-            node_names = get_node_names(node=node, include_hidden_nodes=False)
+            node_names = _get_node_names(node=node, include_hidden_nodes=False)
 
             if not len(node_names):
                 print('No nodes detected in the ROS graph. No policy file was generated.',
@@ -125,23 +124,63 @@ def main(self, *, args):
 
             for node_name in node_names:
                 profile = self.get_profile(policy, node_name)
-                subscribe_topics = get_subscriber_info(node=node, node_name=node_name)
+                subscribe_topics = _get_subscriber_info(node=node, node_name=node_name)
                 if subscribe_topics:
                     self.add_permission(
                         profile, 'topic', 'subscribe', 'ALLOW', subscribe_topics, node_name)
-                publish_topics = get_publisher_info(node=node, node_name=node_name)
+                publish_topics = _get_publisher_info(node=node, node_name=node_name)
                 if publish_topics:
                     self.add_permission(
                         profile, 'topic', 'publish', 'ALLOW', publish_topics, node_name)
-                reply_services = get_service_info(node=node, node_name=node_name)
+                reply_services = _get_service_info(node=node, node_name=node_name)
                 if reply_services:
                     self.add_permission(
                         profile, 'service', 'reply', 'ALLOW', reply_services, node_name)
-                request_services = get_client_info(node=node, node_name=node_name)
+                request_services = _get_client_info(node=node, node_name=node_name)
                 if request_services:
                     self.add_permission(
                         profile, 'service', 'request', 'ALLOW', request_services, node_name)
 
         with open(args.POLICY_FILE_PATH, 'w') as stream:
             dump_policy(policy, stream)
         return 0
+
+
+def _get_node_names(*, node, include_hidden_nodes=False):
+    node_names_and_namespaces = node.get_node_names_and_namespaces()
+    return [
+        _NodeName(
+            node=t[0],
+            ns=t[1],
+            fqn=t[1] + ('' if t[1].endswith('/') else '/') + t[0])
+        for t in node_names_and_namespaces
+        if (
+            include_hidden_nodes or
+            (t[0] and not t[0].startswith(_HIDDEN_NODE_PREFIX))
+        )
+    ]
+
+
+def _get_topics(node_name, func):
+    names_and_types = func(node_name.node, node_name.ns)
+    return [
+        _TopicInfo(
+            fqn=t[0],
+            type=t[1])
+        for t in names_and_types]
+
+
+def _get_subscriber_info(node, node_name):
+    return _get_topics(node_name, node.get_subscriber_names_and_types_by_node)
+
+
+def _get_publisher_info(node, node_name):
+    return _get_topics(node_name, node.get_publisher_names_and_types_by_node)
+
+
+def _get_service_info(node, node_name):
+    return _get_topics(node_name, node.get_service_names_and_types_by_node)
+
+
+def _get_client_info(node, node_name):
+    return _get_topics(node_name, node.get_client_names_and_types_by_node)