// in http://docs.aws.amazon.com/general/latest/gr/sigv4-create-canonical-request.html
func signV4TrimAll(input string) string {
	// Compress adjacent spaces (a space is determined by
	// unicode.IsSpace() internally here) to one space and return
	return strings.Join(strings.Fields(input), " ")
}

import okhttp3.ResponseBody.Companion.asResponseBody
import okhttp3.internal.http.promisesBody
import okio.GzipSource
import okio.buffer
import okio.source
import org.brotli.dec.BrotliInputStream

fun uncompress(response: Response): Response {
  if (!response.promisesBody()) {
    return response
  }
  val body = response.body
  val encoding = response.header("Content-Encoding") ?: return response

First, we create a `GzipRequest` class, which will overwrite the `Request.body()` method to decompress the body in the presence of an appropriate header.

If there's no `gzip` in the header, it will not try to decompress the body.

That way, the same route class can handle gzip compressed or uncompressed requests.

```Python hl_lines="8-15"
{!../../../docs_src/custom_request_and_route/tutorial001.py!}
```

      System.out.println(response.body().string());
    }
  }

  public static void main(String... args) throws Exception {
    new RequestBodyCompression().run();
  }

  /** This interceptor compresses the HTTP request body. Many webservers can't handle this! */
  static class GzipRequestInterceptor implements Interceptor {
    @Override public Response intercept(Chain chain) throws IOException {

Interceptors can be chained. Suppose you have both a compressing interceptor and a checksumming interceptor: you'll need to decide whether data is compressed and then checksummed, or checksummed and then compressed. OkHttp uses lists to track interceptors, and interceptors are called in order.

![Interceptors Diagram](../assets/images/******@****.***)

### Application Interceptors

import okhttp3.MediaType.Companion.toMediaType
import okhttp3.Protocol
import okhttp3.Request
import okhttp3.Response
import okhttp3.ResponseBody.Companion.toResponseBody
import okhttp3.brotli.internal.uncompress
import okio.ByteString
import okio.ByteString.Companion.EMPTY
import okio.ByteString.Companion.decodeHex
import okio.ByteString.Companion.encodeUtf8
import org.junit.jupiter.api.Test

class BrotliInterceptorTest {

  /**
   * Compares two objects using a comparator, <i>if</i> the result of this comparison chain has not
   * already been determined.
   */
  public abstract <T extends @Nullable Object> ComparisonChain compare(
      @ParametricNullness T left, @ParametricNullness T right, Comparator<T> comparator);

  /**

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.brotli

import okhttp3.Interceptor
import okhttp3.Response
import okhttp3.brotli.internal.uncompress

/**
 * Transparent Brotli response support.
 *
 * Adds Accept-Encoding: br to request and checks (and strips) for Content-Encoding: br in

        result.replace("HEADERS", "PUSH_PROMISE") // TODO: Avoid allocation.
      }
      type == TYPE_DATA && flags and FLAG_COMPRESSED != 0 -> {
        result.replace("PRIORITY", "COMPRESSED") // TODO: Avoid allocation.
      }
      else -> result
    }
  }

Harshavardhana <******@****.***> 1713892552 -0700