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Synchronous Interceptors

Synchronous interceptors operate in a blocking manner, directly influencing the real-time flow of messages.

When a message encounters a synchronous interceptor, the message flow is paused. The interceptor processes the message, which may include real-time data manipulation or validation. The message flow then resumes only after the interceptor has completed its operation and returned a processed response.

This execution model is ideal when the output or modification performed by the interceptor is a prerequisite for subsequent steps in the communication sequence. For instance, a synchronous interceptor could be used for message validation, routing decisions, or transforming data format before it reaches its final destination.

How It Works​

Synchronous interceptors follow a blocking execution model, ensuring that the message flow does not proceed until processing is complete.

adk.intercept("validator", (payload, resolve, reject) => {
  if (payload.isValid) {
    resolve({ status: "validated", data: payload });
  } else {
    reject("Validation failed");
  }
});

Here's how the synchronous interceptor works:

  1. Message Capture: The interceptor is triggered when a message enters the channel.
  2. Processing: The interceptor runs its logic (validation, transformation, or routing decisions).
  3. Response: The interceptor must return a resolve (success) or reject (failure).
  4. Pipeline Continuation: The message resumes its journey only after the interceptor responds.