Wait for btcdata pod readiness before reconnecting tunnel

scripts/fetch-year.sh

@@ -50,6 +50,23 @@ trap cleanup EXIT
 trap 'exit 130' INT
 trap 'exit 143' TERM
 
+wait_for_pod() {
+  local selector
+  # Use the service's selector rather than assuming a particular pod label.
+  if ! selector=$(kubectl -n sejs get svc btcdata --request-timeout=10s \
+    -o go-template='{{range $key, $value := .spec.selector}}{{$key}}={{$value}},{{end}}'); then
+    return 1
+  fi
+  selector=${selector%,}
+  if [[ -z $selector ]]; then
+    echo "Service sejs/btcdata has no pod selector." >&2
+    return 1
+  fi
+  echo "Waiting up to 5 minutes for btcdata pods to become Ready..." >&2
+  kubectl -n sejs wait --for=condition=Ready pod --selector="$selector" \
+    --timeout=300s --request-timeout=310s >&2
+}
+
 start_forward() {
   local attempt
   cleanup
@@ -57,6 +74,10 @@ start_forward() {
     echo "Service unavailable on localhost:4101 and kubectl is not installed." >&2
     return 1
   fi
+  if ! wait_for_pod; then
+    echo "btcdata pod readiness check failed; not opening a tunnel." >&2
+    return 1
+  fi
   echo "Starting kubectl port-forward for sejs/btcdata..." >&2
   kubectl -n sejs port-forward svc/btcdata 4101:4101 >&2 &
   forward_pid=$!