risingwavelabs/risingwave · error · ConnectorError

No allow_alter_on_fly fields registered for connection

Error message

No allow_alter_on_fly fields registered for connection: {connection_name}

What it means

Generated-code guard in check_connection_allow_alter_on_fly_fields: no allow_alter_on_fly whitelist is registered for the given connection type (CONNECTION_ALLOW_ALTER_ON_FLY_FIELDS has no entry), so any field-alteration request for this connection is rejected. Generic sentinel for unregistered connections.

Solutions

Re-run code generation to rebuild CONNECTION_ALLOW_ALTER_ON_FLY_FIELDS.
Register allow_alter_on_fly fields for the connection type if it should support them.
Skip this validation for connection types without registered fields.

Example fix

// before
check_connection_allow_alter_on_fly_fields(name, fields)?;
// after
if CONNECTION_ALLOW_ALTER_ON_FLY_FIELDS.contains_key(connection_name_to_prop_type_name(name).unwrap()) {
    check_connection_allow_alter_on_fly_fields(name, fields)?;
}

Defensive patterns

Strategy: type-guard

Validate before calling

fn connection_has_alter_fields(name: &str) -> bool {
    connection_name_to_prop_type_name(name)
        .and_then(|t| CONNECTION_ALLOW_ALTER_ON_FLY_FIELDS.get(t))
        .is_some()
}

Try / catch

if connection_has_alter_fields(name) {
    check_connection_allow_alter_on_fly_fields(name, fields)?;
}

Prevention

Regenerate code after adding connection types
Test that each registered connection type has a registry entry

When it happens

Trigger: Calling check_connection_allow_alter_on_fly_fields for a known connection type whose allow-list was never generated, or when the generated registry is stale.

Common situations: New connection type added without updating the generator inputs; build cache missing freshly generated maps; connection type intentionally has no on-the-fly alterable fields but validation is called anyway.

Understand the failure class

Background: "is required", "must be set", "missing required field": configuration validation errors across open-source libraries — this error's family across 36 libraries.

Related errors

AI-assisted analysis of risingwavelabs/risingwave@6469eb736d (2026-09-11). Data as JSON: /api/errors/4919974fb1b30217. Report an issue: GitHub.

Appendix: source

Thrown at src/connector/src/with_options_test.rs:828

        }}
    }}
    Ok(())
}}

pub fn check_connection_allow_alter_on_fly_fields(
    connection_name: &str,
    fields: &[String],
) -> crate::error::ConnectorResult<()> {{
    use crate::source::connection_name_to_prop_type_name;

    // Convert connection name to the type name key
    let Some(type_name) = connection_name_to_prop_type_name(connection_name) else {{
        return Err(ConnectorError::from(anyhow::anyhow!(
            "Unknown connection: {{connection_name}}"
        )));
    }};
    let Some(allowed_fields) = CONNECTION_ALLOW_ALTER_ON_FLY_FIELDS.get(type_name) else {{
        return Err(ConnectorError::from(anyhow::anyhow!(
            "No allow_alter_on_fly fields registered for connection: {{connection_name}}"
        )));
    }};
    for field in fields {{
        if !allowed_fields.contains(field) {{
            return Err(ConnectorError::from(anyhow::anyhow!(
                "Field '{{field}}' is not allowed to be altered on the fly for connection: {{connection_name}}"
            )));
        }}
    }}
    Ok(())
}}

/// Checks if all given fields are allowed to be altered on the fly for the specified sink connector.
/// Returns Ok(()) if all fields are allowed, otherwise returns a `ConnectorError`.
pub fn check_sink_allow_alter_on_fly_fields(
    sink_name: &str,
    fields: &[String],

View on GitHub (pinned to 6469eb736d)