quickwit-oss/quickwit · error · anyhow::Error

update_function_code response missing code_sha256

Error message

update_function_code response missing code_sha256

What it means

After calling UpdateFunctionCode, the SDK response's code_sha256 field is expected to be present; AWS documents it as always returned, so Quickwit treats a None as a violation of the API contract and errors out. This guards callers who rely on the returned hash for verifying the deployed code version.

Solutions

1. If running against an emulator (LocalStack/moto), upgrade it so UpdateFunctionCode returns code_sha256.
2. Check the aws-sdk-lambda version matches what quickwit-lambda-client expects; upgrade the SDK.
3. As a last resort, fetch the hash via GetFunction/GetFunctionConfiguration after the update instead of relying on the update response.

Example fix

// before
let code_sha256 = response.code_sha256().ok_or_else(|| anyhow!("update_function_code response missing code_sha256"))?.to_string();
// after: fall back to fetching the configuration
let code_sha256 = match response.code_sha256() {
    Some(hash) => hash.to_string(),
    None => client.get_function_configuration().function_name(function_name).send().await?.code_sha256().context("missing code_sha256")?.to_string(),
};

fn has_code_sha256(resp: &UpdateFunctionCodeOutput) -> bool { resp.code_sha256().is_some() }

let sha = deploy_lambda_function(...).await?;
// if this errors, fall back to get_function_configuration to obtain code_sha256

When it happens

Trigger: Calling deploy_lambda_function on an existing function: the UpdateFunctionCode response arrives without code_sha256 — effectively only possible with an unexpected/changed AWS SDK response or a mocked/partial response.

Common situations: AWS API behavior change or SDK upgrade where the field moved/renamed; testing against a stubbed LocalStack/moto that omits code_sha256 in the response.

Understand the failure class

Background: "invalid response format", "malformed payload", "missing data field": when an API returns 200 but the response shape is wrong — this error's family across 23 libraries.

Related errors

• created function has no version number
• failed to create Lambda function
• failed to list Lambda versions for
• lambda function ' ' did not become ready within seconds
• lambda function ' ' last update failed

AI-assisted analysis of quickwit-oss/quickwit@a39730c5cd (2026-09-08). Data as JSON: /api/errors/7c7638629199014e. Report an issue: GitHub.

Appendix: source

Thrown at quickwit/quickwit-lambda-client/src/deploy.rs:382

    function_name: &str,
) -> anyhow::Result<String> {
    info!(
        function_name = %function_name,
        "updating Lambda function code to current binary"
    );

    let response = client
        .update_function_code()
        .function_name(function_name)
        .zip_file(Blob::new(LAMBDA_BINARY))
        .architectures(Architecture::Arm64)
        .send()
        .await
        .context("failed to update Lambda function code")?;

    let code_sha256 = response
        .code_sha256()
        .ok_or_else(|| anyhow!("update_function_code response missing code_sha256"))?
        .to_string();

    wait_for_function_ready(client, function_name).await?;

    Ok(code_sha256)
}

/// Publish a new immutable version from `$LATEST` with our description.
///
/// The `code_sha256` parameter guards against races: if another process
/// overwrote `$LATEST` since our `update_function_code` call, AWS will
/// reject the publish.
///
/// Returns the version number (e.g., "8").
async fn publish_version(
    client: &LambdaClient,
    function_name: &str,
    code_sha256: &str,

View on GitHub (pinned to a39730c5cd)