HTTP is the way modern applications network. It’s how we exchange data & media. Doing HTTP
efficiently makes your stuff load faster and saves bandwidth.

OkHttp is an HTTP client that’s efficient by default:

 * HTTP/2 support allows all requests to the same host to share a socket.
 * Connection pooling reduces request latency (if HTTP/2 isn’t available).
 * Transparent GZIP shrinks download sizes.

## An app with callbacks { #an-app-with-callbacks }

Let's see all this with an example.

Imagine you develop an app that allows creating invoices.

These invoices will have an `id`, `title` (optional), `customer`, and `total`.

The user of your API (an external developer) will create an invoice in your API with a POST request.

    protected String groupPrefix = "{group}";

    /** Prefix used to identify user-based permissions */
    protected String userPrefix = "{user}";

    /** Prefix used to identify allow permissions */
    protected String allowPrefix = "(allow)";

    /** Prefix used to identify deny permissions */
    protected String denyPrefix = "(deny)";

    /** System helper for user/group/role search operations */
    @Resource

 * the client is Microsoft Internet Explorer.
 */

/**
 * A servlet that provides network browsing capabilities for SMB shares using SMB1 protocol.
 * This servlet allows users to browse SMB network resources through a web interface.
 */
public class NetworkExplorer extends HttpServlet {

    /**
     * Default constructor.
     */
    public NetworkExplorer() {
        super();

    // Cause the cache trim job to fail.
    filesystem.setFaultyDelete(cacheDir / "a.0", true)
    taskFaker.runNextTask()

    // Confirm we still allow snapshot reads after a trim failure.
    assertValue("a", "aa", "aa")
    assertValue("b", "bb", "bbb")

    // Allow the test to clean up.
    filesystem.setFaultyDelete(cacheDir / "a.0", false)
  }

  @ParameterizedTest

	vars := mux.Vars(r)
	bucket := vars["bucket"]

	objAPI := api.ObjectAPI()
	if objAPI == nil {
		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrServerNotInitialized), r.URL)
		return
	}

	// Allow putBucketACL if policy action is set, since this is a dummy call
	// we are simply re-purposing the bucketPolicyAction.
	if s3Error := checkRequestAuthType(ctx, r, policy.PutBucketPolicyAction, bucket, ""); s3Error != ErrNone {

	decompressors.Store(Store, Decompressor(io.NopCloser))
	decompressors.Store(Deflate, Decompressor(newFlateReader))
}

// RegisterDecompressor allows custom decompressors for a specified method ID.
// The common methods [Store] and [Deflate] are built in.
func RegisterDecompressor(method uint16, dcomp Decompressor) {
	if _, dup := decompressors.LoadOrStore(method, dcomp); dup {

/**
 * {@link ExtractorBuilder} is a builder class for creating and configuring an {@link ExtractData} object.
 * It encapsulates the process of extracting data from an input stream using a specified or detected extractor.
 * The builder allows setting parameters such as MIME type, filename, extractor name, maximum content length,
 * and cache file size to optimize the extraction process.
 *
 * <p>

 *  Fix: OkHttp no longer shares timeouts between pooled connections. This was
    causing some applications to crash when connections were reused.
 *  Fix: `OkApacheClient` now allows an empty `PUT` and `POST`.
 *  Fix: Websockets no longer rebuffer socket streams.
 *  Fix: Websockets are now better at handling close frames.
 *  Fix: Content type matching is now case insensitive.

Let's look at how we can make that work.

## pytest.mark.anyio { #pytest-mark-anyio }

If we want to call asynchronous functions in our tests, our test functions have to be asynchronous. AnyIO provides a neat plugin for this, that allows us to specify that some test functions are to be called asynchronously.

## HTTPX { #httpx }

Even if your **FastAPI** application uses normal `def` functions instead of `async def`, it is still an `async` application underneath.