Testing Secret Redaction in API Logs and Errors
Verify that secrets stay out of logs, error responses and support artifacts, including nested payloads and failed configuration validation.
Overview
When translating these concepts into an integration, keep the scope described by the wallet history api with the result. The examples in wallet transaction history and smart contract event logs show how the same distinction affects neighbouring data questions.
Redaction is most reliable when sensitive fields are excluded or transformed before they reach logging systems. A promise not to inspect logs later is not a technical boundary.
Define sensitive inputs
Cover authorisation headers, API keys, session tokens, signed reusable authorisations and credential-bearing URLs. Prefer allowlisted safe diagnostic fields over serialising whole request objects. Redaction must also handle nested errors and library exceptions that embed request configuration. A short masked display should not reveal enough material to be reusable.
Worked example: an HTTP client exception
A request fails and the client library attaches its full configuration, including headers, to the exception. Logging the exception object can leak the key even though the application never explicitly logs that field. Map it into a safe error code, status and correlation ID before recording it.
Test success and failure paths
Use clearly synthetic sentinel values and assert they do not appear in logs, CLI output, reports or browser responses. Include malformed configuration and timeout errors. Keep tests independent of real credentials. Redaction tests complement access controls and retention; they do not justify collecting unnecessary secrets in the first place.
A practical acceptance test
Place synthetic sentinel secrets in headers, nested exceptions and malformed credential URLs. Exercise success, timeout and validation errors, then scan all captured logs and responses. None should contain the sentinel. Assertions should also verify that useful safe codes remain, preventing a false pass achieved merely by suppressing every diagnostic without a reviewable failure result.
Questions about the topic
Frequently asked questions
Can nested exceptions leak credentials?
Yes. Libraries can attach request configuration to errors.
Should tests use real keys to verify masking?
No. Synthetic sentinel values are sufficient and safer.
Standards & technical documentation
