## Version 4.5.0-RC1

_2020-03-17_

**This release candidate turns on web socket compression.**

The [spec][rfc_7692] includes a sophisticated mechanism for client and server to negotiate
compression features. We strive to offer great performance in our default configuration and so we're
making compression the default for everyone starting with this release candidate.

# Virtual Environments { #virtual-environments }

When you work in Python projects you probably should use a **virtual environment** (or a similar mechanism) to isolate the packages you install for each project.

/// info

If you already know about virtual environments, how to create them and use them, you might want to skip this section. 🤓

///

/// tip

A **virtual environment** is different than an **environment variable**.

    HTTPS connection. If you continue to need to connect to webservers
    running SSLv3, you must manually configure your own `ConnectionSpec`.

 *  **OkHttp now offers interceptors.** Interceptors are a powerful mechanism
    that can monitor, rewrite, and retry calls. The [interceptors doc][interceptors] is a full
    introduction to this new API.

 *  New: APIs to iterate and selectively clear the response cache.

		return false
	}

	notInitialized := strings.Contains(err.Error(), "Server not initialized, please try again") ||
		errors.Is(err, errServerNotInitialized)

	// Initializing sub-systems needs a retry mechanism for
	// the following reasons:
	//  - Read quorum is lost just after the initialization
	//    of the object layer.
	//  - Write quorum not met when upgrading configuration

sasl_username    (string)    username for SASL/PLAIN or SASL/SCRAM authentication
sasl_password    (string)    password for SASL/PLAIN or SASL/SCRAM authentication
sasl_mechanism   (string)    sasl authentication mechanism, default 'PLAIN'
tls_client_auth  (string)    clientAuth determines the Kafka server's policy for TLS client auth
sasl             (on|off)    set to 'on' to enable SASL authentication

# errors.
# There is ongoing work on Bazel team's side to provide support for transitive
# shared libraries. As part of migrating to transitive shared libraries, we
# hope to provide a better mechanism for control over symbol exporting, and
# then tackle this issue again.
#
# TODO: Remove the following two lines once TF doesn't depend on Bazel wrapping
# all library archives in -whole_archive -no_whole_archive.

		kafkaArgs.SASL.User = env.Get(saslUsernameEnv, kv.Get(target.KafkaSASLUsername))
		kafkaArgs.SASL.Password = env.Get(saslPasswordEnv, kv.Get(target.KafkaSASLPassword))
		kafkaArgs.SASL.Mechanism = env.Get(saslMechanismEnv, kv.Get(target.KafkaSASLMechanism))

		if err = kafkaArgs.Validate(); err != nil {
			return nil, err
		}

		kafkaTargets[k] = kafkaArgs
	}

	return kafkaTargets, nil

### SIG CLI

SIG CLI's main focus this release was on refactoring `kubectl` internals to improve composability, readability and testability of `kubectl` commands. Those refactors will allow the team to extract a mechanism for extensibility of kubectl -- that is, plugins -- in the next releases.

### SIG Cluster Lifecycle

typedef struct TF_Library TF_Library;

// Load the library specified by library_filename and register the ops and
// kernels present in that library.
//
// Pass "library_filename" to a platform-specific mechanism for dynamically
// loading a library. The rules for determining the exact location of the
// library are platform-specific and are not documented here.
//

* Add mechanism for Admission Webhooks to specify which version of AdmissionReview they support ([#74998](https://github.com/kubernetes/kubernetes/pull/74998), [@mbohlool](https://github.com/mbohlool))
    * Add mechanism for CRD Conversion Webhooks to specify which version of ConversionReview they support