exec command returns before command is executed

[bodycombathuang]

async function func1() { const command = ['tar', 'zcf', '-']; command.push('-C', cwd); command.push(srcPath); const writerStream = fs.createWriteStream(srcPath+".tar") const errStream = new WritableStreamBuffer();

await exec.exec(
    namespace,
    podName,
    containerName,
    command,
    writerStream,
    errStream,
    null,
    false,
    async ({ status }) => {
        writerStream.close();

        if (status === 'Failure' || errStream.size()) {
            throw new Error(`Error from cpFromPod - details: \n ${errStream.getContentsAsString()}`);
        }
        fs.createReadStream(`${srcPath}.tar`).pipe(tar.extract({cwd:tgtPath}));

    },
);

} func1() fs.rmSync(srcPath+".tar"(

I run the above code, fs.rmSync throws the tar file does not exist error, I feel the command is not executed immediately after exec finishes

[brendandburns]

exec returns a promise to the underlying WebSocket, not to the command execution. If you want to wait for the command execution to complete, you need to wait on that callback that you passed in (the function that calls fs.createReadStream(...)

[bodycombathuang]

hi @brendandburns how to wait on that callback? https://github.com/kubernetes-client/javascript/blob/master/src/cp.ts, I can see a sample here, but I do not know how to wait on that callback, could you help me

[brendandburns]

You need to create a Promise before you make the call to exec and then resolve that promise within the callback. Then wait for that promise to complete before you move on after the exec

Details of promises here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise

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/lifecycle stale

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/lifecycle rotten

[k8s-triage-robot]

The Kubernetes project currently lacks enough active contributors to adequately respond to all issues and PRs.

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• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
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/close not-planned

[k8s-ci-robot]

@k8s-triage-robot: Closing this issue, marking it as "Not Planned".

In response to this:

The Kubernetes project currently lacks enough active contributors to adequately respond to all issues and PRs.

This bot triages issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Reopen this issue with /reopen
• Mark this issue as fresh with /remove-lifecycle rotten
• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/close not-planned

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