Merge branch 'main' into feat/SMS-490-intra-app-comm-pattern

Author: adhityaravi

tests/integration/helpers.py

@@ -134,3 +134,40 @@ def assert_request_returns_http_code(
     assert (
         returned_code == code
     ), f"Expected {code} but got {returned_code} for {source_unit} -> {target_url} on {method}"
+
+
+@retry(
+    wait=wait_exponential(multiplier=1, min=1, max=10), stop=stop_after_delay(120), reraise=True
+)
+def assert_tcp_connectivity(
+    model: str, source_unit: str, host: str, port: int, inverse_check: bool = False
+):
+    """Test TCP connectivity from source unit to target host:port using /dev/tcp.
+
+    Args:
+        model: Juju model name
+        source_unit: Source unit name (e.g., "sender/0")
+        host: Target hostname or IP
+        port: Target port number
+        inverse_check: Pass if the connection fails
+    """
+    cmd = f'timeout 5 bash -c "echo >/dev/tcp/{host}/{port}"'
+
+    try:
+        _ = sh.juju.ssh(  # pyright: ignore
+            "-m",
+            model,
+            source_unit,
+            cmd,
+            _return_cmd=True,
+        )
+        exit_code = 0
+        logger.info(f"TCP connectivity test succeeded: {source_unit} -> {host}:{port}")
+    except sh.ErrorReturnCode as e:
+        exit_code = e.exit_code
+        logger.info(f"TCP connectivity test failed with exit code {exit_code}: {source_unit} -> {host}:{port}")
+
+    if not inverse_check:
+        assert exit_code == 0, f"Expected TCP connection to {host}:{port} to succeed, but got exit code {exit_code}"
+    else:
+        assert exit_code != 0, f"Expected TCP connection to {host}:{port} to fail, but it succeeded"

tests/integration/test_charm.py

@@ -12,6 +12,7 @@
     APP_NAME,
     RESOURCES,
     assert_request_returns_http_code,
+    assert_tcp_connectivity,
     istio_k8s,
     validate_labels,
     validate_policy_exists,
@@ -328,8 +329,8 @@ async def test_modeloperator_rule(ops_test: OpsTest, service_mesh_tester):
         service_mesh_tester, application_name="sender", resources=resources, trust=True
     )
     await omm.model.wait_for_idle(status="active")
-    # Return code is 400 because I do not know how to properly format an api call to the modeloperator. But we only
-    # care that the request reached its destination.
-    assert_request_returns_http_code(
-        omm.model.name, "sender/0", f"http://modeloperator.{ops_test.model.name}:17071", code=400
+    # Test TCP connectivity to modeloperator - we only care that the network connection can be established,
+    # proving that the service mesh allows traffic from off-mesh workloads to the modeloperator
+    assert_tcp_connectivity(
+        omm.model.name, "sender/0", f"modeloperator.{ops_test.model.name}.svc.cluster.local", 17071
     )