Keep bot jobs and harness calls from hanging

src/functions/backend/docker/ensure-docker-network.ts

@@ -2,12 +2,38 @@ import { AppData } from "@/src/data/app-data";
 import dockerRequest from "./docker-request";
 import grabAppContainer from "./grab-app-container";
 
+/**
+ * Docker can still be coming up when the app container starts (a host
+ * reboot, especially), so a transient failure is retried before the app
+ * gives up on networking.
+ */
+const Attempts = 3;
+const RetryMs = 2000;
+
 /**
  * Makes sure the network computers run on (`AppData.DockerNetworkName`)
  * exists and, when the app runs in docker, that its container is on it,
  * so it reaches computers by name.
  */
 export default async function ensureDockerNetwork() {
+    let last_error: unknown;
+
+    for (let attempt = 1; attempt <= Attempts; attempt++) {
+        try {
+            return await connectNetwork();
+        } catch (error: unknown) {
+            last_error = error;
+
+            if (attempt < Attempts) {
+                await new Promise((resolve) => setTimeout(resolve, RetryMs));
+            }
+        }
+    }
+
+    throw last_error;
+}
+
+async function connectNetwork() {
     const name = AppData.DockerNetworkName;
     const existing = await dockerRequest({ path: `/networks/${encodeURIComponent(name)}` });