* enqueue messages followed by pongs, but this sends pongs followed by messages. Pongs are always
   * written in the order they were enqueued.
   *
   * If a frame cannot be sent - because there are none enqueued or because the web socket is not
   * connected - this does nothing and returns false. Otherwise this returns true and the caller

Calls are executed in one of two ways:

 * **Synchronous:** your thread blocks until the response is readable.
 * **Asynchronous:** you enqueue the request on any thread, and get [called back](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-callback/) on another thread when the response is readable.

Most of the code is actually the same.

So, we are going to focus only on the differences.

## File structure

Let's say you have a directory named `my_super_project` that contains a sub-directory called `sql_app` with a structure like this:

```
.
└── sql_app
    ├── __init__.py
    ├── crud.py
    ├── database.py
    ├── main.py
    └── schemas.py
```

 * This is typical for Java but atypical for HTTP/2. This is motivated by exception transparency:
 * an [IOException] that was triggered by a certain caller can be caught and handled by that caller.
 */
@Suppress("NAME_SHADOWING")
class Http2Connection internal constructor(builder: Builder) : Closeable {
  internal val lock: ReentrantLock = ReentrantLock()

understand why it is I hate cats and dogs.'

  It was high time to go, for the pool was getting quite crowded
with the birds and animals that had fallen into it:  there were a
Duck and a Dodo, a Lory and an Eaglet, and several other curious
creatures.  Alice led the way, and the whole party swam to the
shore.



                           CHAPTER III

```Python
if not (credentials.username == "stanleyjobson") or not (credentials.password == "swordfish"):
    # Return some error
    ...
```

But by using the `secrets.compare_digest()` it will be secure against a type of attacks called "timing attacks".

### Timing Attacks

But what's a "timing attack"?

Let's imagine some attackers are trying to guess the username and password.

   the `SecretManager` to Envoy, without much business logic. For each resource requested by Envoy, the SDS server
   will call `SecretManager.GenerateSecret(resourceName)`
1. When `GenerateSecret` is called, the `SecretManager` is expected to return a new certificate. This can occur in a few ways.
   1. The most common method (pictured above) is to sign a new certificate by calling the configured CA. Typically, this is Istiod.

start using the least used cluster. This expansion strategy works endlessly, so you can perpetually expand your clusters as needed.  When you restart, it is immediate and non-disruptive to the applications. Each group of servers in the command-line is called a pool. There are 2 server pools in this example. New objects are placed in server pools in proportion to the amount of free space in each pool. Within each pool, the location of the erasure-set of drives is determined based on a deterministic hashing...

```

A response similar to this one should be displayed:

```
Generating a 3072 bit RSA private key...
```

#### 3.3.3 Generate a public certificate

Create a file called `cert.cnf` with the content below. This file contains all of the information necessary to generate a certificate using `certtool.exe`:

```
# X.509 Certificate options
#
# DN options

    This is most useful when writing the request body is destructive.

 *  New: We've added `requestFailed()` and `responseFailed()` methods to `EventListener`. These
    are called instead of `requestBodyEnd()` and `responseBodyEnd()` in some failure situations.
    They may also be fired in cases where no event was published previously. In this release we did