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Transform Response

Transform Response in Solvix allows you to modify, normalize, or enhance the response before it is returned to your application.

It is useful for shaping API responses into a consistent format across your app.

What is Transform Response?​

Transform Response is a function that runs after the response is received but before it is returned to the caller.

It allows you to:

  • Modify response data
  • Normalize API formats
  • Handle global response structures
  • Add custom metadata

Why use Transform Response?​

In real-world applications:

  • Different APIs return different formats
  • You may want a unified response structure
  • You may need to extract nested data

Transform Response ensures consistency.

Basic Usage​

const client = createClient({
  transformResponse: async (response) => {
    const data = await response.json();

    return {
      ...response,
      data,
    };
  },
});

Example: Normalize API Response​

transformResponse: async (response) => {
  const data = await response.json();

  return new Response(
    JSON.stringify({
      success: true,
      payload: data,
    }),
    {
      status: response.status,
    },
  );
};

Example: Extract Nested Data​

transformResponse: async (response) => {
  const data = await response.json();

  return new Response(JSON.stringify(data.result), {
    status: response.status,
  });
};

Example: Add Metadata​

transformResponse: async (response) => {
  const data = await response.json();

  return new Response(
    JSON.stringify({
      data,
      receivedAt: Date.now(),
    }),
    {
      status: response.status,
    },
  );
};

Execution Timing​

Transform Response runs:

  1. After transport
  2. After retries
  3. Before final response is returned

Important Rules​

  • Must return a valid Response
  • Handle JSON parsing carefully
  • Avoid multiple body reads without cloning

Common Mistake​

Reading response twice ❌​

await response.json();
await response.json(); // ❌ error

Correct way ✅​

const cloned = response.clone();
const data = await cloned.json();

When to use Transform Response vs Middleware​

Use Transform Response when:

  • You only need to modify response
  • You want clean and direct logic

Use Middleware when:

  • You need full control (before + after)
  • You need error interception

Integration​

Works with:

  • Snapshot debugging
  • Profiling
  • Retry engine

Summary​

Transform Response provides a simple and powerful way to standardize and enhance API responses.