Consider swapped container's ports when choosing proxy image

Fixes #983

newsfragments/983.bugfix

@@ -0,0 +1 @@
+Telepresence correctly forwards privileged ports when using swap-deployment.

telepresence/proxy/deployment.py

@@ -137,13 +137,6 @@ def _get_container_name(container, deployment_json):
     return container
 
 
-def _merge_expose_ports(expose, container_json):
-    expose.merge_automatic_ports([
-        port["containerPort"] for port in container_json.get("ports", [])
-        if port["protocol"] == "TCP"
-    ])
-
-
 def supplant_deployment(
     runner: Runner, deployment_arg: str, expose: PortMapping,
     add_custom_nameserver: bool
@@ -172,11 +165,11 @@ def supplant_deployment(
     )
     container = _get_container_name(container, deployment_json)
 
-    new_deployment_json, orig_container_json = new_swapped_deployment(
+    new_deployment_json = new_swapped_deployment(
         deployment_json,
         container,
         run_id,
-        get_image_name(expose),
+        expose,
         add_custom_nameserver,
     )
 
@@ -230,8 +223,6 @@ def delete_new_deployment(check):
     )
     resize_original(0)
 
-    _merge_expose_ports(expose, orig_container_json)
-
     span.end()
     return new_deployment_name, run_id
 
@@ -240,9 +231,9 @@ def new_swapped_deployment(
     old_deployment: Dict,
     container_to_update: str,
     run_id: str,
-    telepresence_image: str,
+    expose: PortMapping,
     add_custom_nameserver: bool,
-) -> Tuple[Dict, Dict]:
+) -> Dict:
     """
     Create a new Deployment that uses telepresence-k8s image.
 
@@ -257,8 +248,8 @@ def new_swapped_deployment(
     7. Adds TELEPRESENCE_CONTAINER_NAMESPACE env variable so the forwarder does
        not have to access the k8s API from within the pod.
 
-    Returns dictionary that can be encoded to JSON and used with kubectl apply,
-    and contents of swapped out container.
+    Returns dictionary that can be encoded to JSON and used with kubectl apply.
+    Mutates the passed-in PortMapping to include container ports.
     """
     new_deployment_json = deepcopy(old_deployment)
     new_deployment_json["spec"]["replicas"] = 1
@@ -272,7 +263,12 @@ def new_swapped_deployment(
         old_deployment["spec"]["template"]["spec"]["containers"],
     ):
         if container["name"] == container_to_update:
-            container["image"] = telepresence_image
+            # Merge container ports into the expose list
+            expose.merge_automatic_ports([
+                port["containerPort"] for port in container.get("ports", [])
+                if port["protocol"] == "TCP"
+            ])
+            container["image"] = get_image_name(expose)
             # Not strictly necessary for real use, but tests break without this
             # since we don't upload test images to Docker Hub:
             container["imagePullPolicy"] = "IfNotPresent"
@@ -306,7 +302,7 @@ def new_swapped_deployment(
                     }
                 }
             })
-            return new_deployment_json, old_container
+            return new_deployment_json
 
     raise RuntimeError(
         "Couldn't find container {} in the Deployment.".
@@ -377,16 +373,14 @@ def apply_json(json_config):
 
     container = _get_container_name(container, dc_json)
 
-    new_dc_json, orig_container_json = new_swapped_deployment(
+    new_dc_json = new_swapped_deployment(
         dc_json,
         container,
         run_id,
-        get_image_name(expose),
+        expose,
         add_custom_nameserver,
     )
 
     apply_json(new_dc_json)
 
-    _merge_expose_ports(expose, orig_container_json)
-
     return deployment, run_id