## Other middlewares { #other-middlewares }

There are many other ASGI middlewares.

For example:

* <a href="https://github.com/encode/uvicorn/blob/master/uvicorn/middleware/proxy_headers.py" class="external-link" target="_blank">Uvicorn's `ProxyHeadersMiddleware`</a>

     */
    long deadline = System.nanoTime() + unit.toNanos(timeout);
    int added = 0;
    while (added < numElements) {
      // we could rely solely on #poll, but #drainTo might be more efficient when there are multiple
      // elements already available (e.g. LinkedBlockingQueue#drainTo locks only once)
      added += q.drainTo(buffer, numElements - added);

            + "1234567890";
    assertEquals(s, xmlEscaper.escape(s));

    // Test ASCII control characters.
    for (char ch = 0; ch < 0x20; ch++) {
      if (ch == '\t' || ch == '\n' || ch == '\r') {
        // Only these whitespace chars are permitted in XML,
        if (shouldEscapeWhitespaceChars) {
          assertEscaping(xmlEscaper, "&#x" + Integer.toHexString(ch).toUpperCase() + ";", ch);
        } else {

These headers preserve information about the original request that would otherwise be lost:

* **X-Forwarded-For**: The original client's IP address
* **X-Forwarded-Proto**: The original protocol (`https`)
* **X-Forwarded-Host**: The original host (`mysuperapp.com`)

  private var requestBodyOpen = false

  /** True if this call still has a response body open. */
  private var responseBodyOpen = false

  /** True if there are more exchanges expected for this call. */
  private var expectMoreExchanges = true

  // These properties are accessed by canceling threads. Any thread can cancel a call, and once it's
  // canceled it's canceled forever.

  @Volatile private var canceled = false

          <!-- TODO(cpovirk): Move this to the parent after making the package-list files available there. -->
          <!-- We add the link ourselves so that we can choose Java 21 over the version that -source suggests. -->
          <detectJavaApiLink>false</detectJavaApiLink>
          <offlineLinks>

</AssumeRoleWithCertificateResponse>
```

## Authentication Flow

A client can request temp. S3 credentials via the STS API. It can authenticate via a client certificate and obtain a access/secret key pair as well as a session token. These credentials are associated to an S3 policy at the MinIO server.

 * cause DNS services to be accessed. For this reason, you should prefer these methods as much as
 * possible over their JDK equivalents whenever you are expecting to handle only IP address string
 * literals -- there is no blocking DNS penalty for a malformed string.
 *
 * <p>When dealing with {@link Inet4Address} and {@link Inet6Address} objects as byte arrays (vis.

   * powerSet(ImmutableSet.of(1, 2))} returns the set {@code {{}, {1}, {2}, {1, 2}}}.
   *
   * <p>Elements appear in these subsets in the same iteration order as they appeared in the input
   * set. The order in which these subsets appear in the outer set is undefined. Note that the power
   * set of the empty set is not the empty set, but a one-element set containing the empty set.
   *

 *  New: Buffer WebSocket frames for better performance.
 *  New: Drop support for `TLS_DHE_DSS_WITH_AES_128_CBC_SHA`, our only remaining
    DSS cipher suite. This is consistent with Firefox and Chrome which have also
    dropped these cipher suite.

## Version 2.5.0

_2015-08-25_

 *  **Timeouts now default to 10 seconds.** Previously we defaulted to never
    timing out, and that was a lousy policy. If establishing a connection,