Handle failed Docker startup from unusable CERT_PATH (+HOST) env vars

Author: pimterry

src/index.ts

@@ -70,11 +70,17 @@ function manageBackgroundServices(
     httpsConfig: { certPath: string, certContent: string }
 ) {
     standalone.on('mock-server-started', async (server) => {
-        startDockerInterceptionServices(server.port, httpsConfig, ruleParameters);
+        startDockerInterceptionServices(server.port, httpsConfig, ruleParameters)
+        .catch((error) => {
+            console.log("Could not start Docker components:", error);
+        });
     });
 
     standalone.on('mock-server-stopping', (server) => {
-        stopDockerInterceptionServices(server.port, ruleParameters);
+        stopDockerInterceptionServices(server.port, ruleParameters)
+        .catch((error) => {
+            console.log("Could not stop Docker components:", error);
+        });
     });
 }
 

src/interceptors/docker/docker-interception-services.ts

@@ -20,7 +20,10 @@ import {
     stopDockerTunnel,
 } from './docker-tunnel-proxy';
 
-export const isDockerAvailable = () => new Docker().ping().then(() => true).catch(() => false);
+export const isDockerAvailable = () =>
+    (async () => new Docker().ping())() // Catch sync & async setup errors
+    .then(() => true)
+    .catch(() => false);
 
 const IPv4_IPv6_PREFIX = "::ffff:";
 

src/interceptors/docker/docker-interceptor.ts

@@ -20,7 +20,13 @@ export class DockerContainerInterceptor implements Interceptor {
         private config: HtkConfig
     ) {}
 
-    private docker = new Docker();
+    private _docker: Docker | undefined;
+    private getDocker() {
+        if (!this._docker) {
+            this._docker = new Docker();
+        }
+        return this._docker;
+    }
 
     async isActivable(): Promise<boolean> {
         return isDockerAvailable();
@@ -32,7 +38,7 @@ export class DockerContainerInterceptor implements Interceptor {
             // We cache the containers query whilst it's active, because this gets hit a lot,
             // usually directly in parallel by getMetadata and isActive, and this ensures
             // that concurrent calls all just run one lookup and use the same result.
-            this._containersPromise = this.docker.listContainers()
+            this._containersPromise = this.getDocker().listContainers()
                 .finally(() => { this._containersPromise = undefined; });
         }
         return this._containersPromise;
@@ -70,7 +76,7 @@ export class DockerContainerInterceptor implements Interceptor {
         } as const;
 
         ensureDockerServicesRunning(proxyPort);
-        await restartAndInjectContainer(this.docker, options.containerId, interceptionSettings);
+        await restartAndInjectContainer(this.getDocker(), options.containerId, interceptionSettings);
     }
 
     async isActive(proxyPort: number): Promise<boolean> {