Class HttpTransportAbstract

The HTTP transport SPI: one request in, one response out, and nothing else. This is the type an application, a platform or a test implements to route the SDK's mirror node REST traffic through its own HTTP stack (a corporate proxy, mTLS, tracing, or a platform without fetch).

Install one with client.setMirrorNodeHttpConfig({ ...client.getMirrorNodeHttpConfig(), transport }). A transport the application injects is owned by the application: the SDK never closes it.

An implementation must satisfy the following; everything not listed is free.

• A non-2xx status is a successful exchange. Return the HttpResponse carrying the status; never fail on a status code.
• Only a failure to obtain a response fails the call, ideally with an HttpTransportError carrying one of the seven codes, so the retry policy knows whether repeating the exchange can help. Any other error is treated as non-retryable.
• No policy at this layer. No retry, no backoff, no status interpretation. The mirror node adapter above owns those.
• Honour request.deadline by abandoning the exchange, body included, and failing with timeout-error.
• Honour the AbortSignal by ending the exchange and failing with cancelled-error, and release the abort listener when the exchange ends so a long-lived signal does not accumulate closures.
• Buffer the whole body before resolving.
• roundTrip is safe to call concurrently, including concurrently with close.
• After close, roundTrip fails fast with client-closed-error. close is idempotent, never reports failure, and releases only what the transport itself owns.