improvement(k8s): better error logging for kubectl port forwards

garden-service/src/plugins/kubernetes/port-forward.ts

@@ -22,6 +22,7 @@ import { KubernetesResource } from "./types"
 import { ForwardablePort } from "../../types/service"
 import { isBuiltIn } from "./util"
 import { LogEntry } from "../../logger/log-entry"
+import { RuntimeError } from "../../exceptions"
 
 // TODO: implement stopPortForward handler
 
@@ -90,8 +91,25 @@ export async function getPortForward(
     log.silly(`Running 'kubectl ${portForwardArgs.join(" ")}'`)
 
     const proc = await kubectl.spawn({ log, provider: k8sCtx.provider, namespace, args: portForwardArgs })
+    let output = ""
+
+    return new Promise((resolve, reject) => {
+      let resolved = false
+
+      const portForward = { targetResource, port, proc, localPort }
+
+      proc.on("close", (code) => {
+        if (registeredPortForwards[key]) {
+          delete registeredPortForwards[key]
+        }
+        if (!resolved) {
+          reject(new RuntimeError(
+            `Port forward exited with code ${code} before establishing connection:\n\n${output}`,
+            { code, portForward },
+          ))
+        }
+      })
 
-    return new Promise((resolve) => {
       proc.on("error", (error) => {
         !proc.killed && proc.kill()
         throw error
@@ -100,13 +118,19 @@ export async function getPortForward(
       proc.stdout!.on("data", (line) => {
         // This is unfortunately the best indication that we have that the connection is up...
         log.silly(`[${targetResource} port forwarder] ${line}`)
+        output += line
 
         if (line.toString().includes("Forwarding from ")) {
-          const portForward = { targetResource, port, proc, localPort }
           registeredPortForwards[key] = portForward
+          resolved = true
           resolve(portForward)
         }
       })
+
+      proc.stderr!.on("data", (line) => {
+        log.silly(`[${targetResource} port forwarder] ${line}`)
+        output += line
+      })
     })
   }))
 }

garden-service/src/util/ext-tools.ts

@@ -263,11 +263,14 @@ export class BinaryCmd extends Library {
     if (!args) {
       args = []
     }
+    if (!cwd) {
+      cwd = dirname(path)
+    }
 
-    log.debug(`Execing ${path} ${args.join(" ")}`)
+    log.debug(`Execing '${path} ${args.join(" ")}' in ${cwd}`)
 
     const proc = execa(path, args, {
-      cwd: cwd || dirname(path),
+      cwd,
       timeout: this.getTimeout(timeout) * 1000,
       env,
       input,
@@ -302,7 +305,16 @@ export class BinaryCmd extends Library {
 
   async spawn({ args, cwd, env, log }: ExecParams) {
     const path = await this.getPath(log)
-    return crossSpawn(path, args || [], { cwd: cwd || dirname(path), env })
+
+    if (!args) {
+      args = []
+    }
+    if (!cwd) {
+      cwd = dirname(path)
+    }
+
+    log.debug(`Spawning '${path} ${args.join(" ")}' in ${cwd}`)
+    return crossSpawn(path, args, { cwd, env })
   }
 
   async spawnAndWait({ args, cwd, env, log, ignoreError, outputStream, timeout, tty }: SpawnParams) {