risingwavelabs/risingwave · error · SchemaFetchError::Client

schema registry client error: {0}

Error message

schema registry client error: {0}

What it means

SchemaFetchError::Client wraps schema_registry::SchemaRegistryClientError: the schema registry client itself failed — request construction, HTTP transport errors, or non-success registry responses handled at client level.

Source

Thrown at src/connector/src/schema/mod.rs:71

    #[error(transparent)]
    AwsGlue(#[from] Box<aws_sdk_glue::operation::get_schema_version::GetSchemaVersionError>),
    #[error(transparent)]
    MalformedResponse(#[from] MalformedResponseError),
    #[error("schema version id invalid: {0}")]
    InvalidUuid(#[from] uuid::Error),
    #[error("schema compilation error: {0}")]
    SchemaCompile(
        #[source]
        #[backtrace]
        risingwave_common::error::BoxedError,
    ),
    #[error("{0}")] // source+{0} is effectively transparent but allows backtrace
    YetToMigrate(
        #[source]
        #[backtrace]
        ConnectorError,
    ),
    #[error("schema registry client error: {0}")]
    Client(#[from] schema_registry::SchemaRegistryClientError),
}

View on GitHub (pinned to 6469eb736d)

Solutions

1. Verify the registry URL is reachable from the RisingWave node: curl http://<registry>/subjects.
2. Check network/TLS: firewall rules, DNS, proxy and CA certificates.
3. Check registry auth requirements and registry logs for 4xx/5xx causes.

Example fix

// before
WITH (schema.registry = 'http://registry-internal:8081') // unreachable from RW node
// after
WITH (schema.registry = 'http://localhost:8081') // or fix network/DNS

// preflight connectivity check
// curl -fsS http://registry:8081/subjects >/dev/null || echo 'registry unreachable'

match fetch_schema() {
    Err(e) if e.to_string().starts_with("schema registry client error") => {
        // check network/auth, retry with backoff for transient 5xx
    }
    Err(e) => return Err(e.into()),
    Ok(s) => s,
}

When it happens

Trigger: Any schema registry client call (fetch schema by id/subject/version, Confluent requests) failing due to network issues, DNS failure, TLS errors, or registry-side errors before response parsing.

Common situations: Registry unreachable (wrong host/port, firewall), registry returning 4xx/5xx (auth required, subject not found), TLS certificate issues in on-prem deployments.

Understand the failure class

Background: 'Something went wrong' / 'Request failed (500)' / 'HTTP error! status: 404' — what failed HTTP requests actually mean and how to find the real cause — this error's family across 28 libraries.

Related errors

• request error
• confluent registry send req error: {0}
• Vault API returned error status: {} - {}
• Malformed response: {message}
• all request confluent registry all timeout, {context} {}

AI-assisted analysis of risingwavelabs/risingwave@6469eb736d (2026-09-11). Data as JSON: /api/errors/d28cd668c9cd0dec. Report an issue: GitHub.