libs/tools: add resolve_identifier()

libs/tools.py

@@ -0,0 +1,31 @@
+from bundlewrap.exceptions import NoSuchGroup, NoSuchNode
+from ipaddress import ip_address
+
+def resolve_identifier(repo, identifier):
+    """
+    Try to resolve an identifier (group or node). Return a set of ip
+    addresses valid for this identifier.
+    """
+    try:
+        nodes = {repo.get_node(identifier)}
+    except NoSuchNode:
+        try:
+            nodes = repo.nodes_in_group(identifier)
+        except NoSuchGroup:
+            try:
+                return {ip_address(identifier)}
+            except:
+                return set()
+
+    found_ips = set()
+    for node in nodes:
+        for interface, config in node.metadata.get('interfaces', {}).items():
+            for ip in config.get('ipv4', set()):
+                found_ips.add(ip_address(ip))
+            for ip in config.get('ipv4', set()):
+                found_ips.add(ip_address(ip))
+
+        if node.metadata.get('external_ipv4'):
+            found_ips.add(ip_address(node.metadata.get('external_ipv4')))
+
+    return found_ips