Add release notes for v2.4.0-beta release

Add release notes for v2.4.0-beta release.

Signed-off-by: David Enyeart <enyeart@us.ibm.com>

Makefile

@@ -48,7 +48,7 @@
 #   - verify - runs unit tests for only the changed package tree
 
 ALPINE_VER ?= 3.13
-BASE_VERSION = 2.4.0
+BASE_VERSION = 2.4.0-beta
 
 # 3rd party image version
 # These versions are also set in the runners in ./integration/runners/

release_notes/v2.4.0-beta.md

@@ -0,0 +1,167 @@
+v2.4.0-beta Release Notes - August 12, 2021
+===========================================
+
+New features
+------------
+
+**[FABGW-1] Fabric Gateway**
+
+The Hyperledger Fabric v2.4.0 Beta contains the new Fabric Gateway feature.
+
+The Fabric Gateway is a new component that will implement much of the high-level 'gateway' programming model in the Fabric peer,
+enabling the removal of much of the transaction submission and query logic from client applications, and shifting it to a common gateway component running within the Fabric peer.
+The various client SDKs can therefore be slimmer, more consistent, and require less maintenance.
+
+The Fabric Gateway will also simplify the administrative overhead of running a Fabric network because client applications
+will be able to connect and submit transactions via a single network port rather than the current situation where ports
+have to be opened from a client application to multiple peers across potentially multiple organizations.
+
+The Fabric Gateway is delivered along with slim SDKs in the [https://github.com/hyperledger/fabric-gateway](https://github.com/hyperledger/fabric-gateway) repository.
+Check out the [client application samples](https://github.com/hyperledger/fabric-gateway/tree/main/samples).
+
+**[FAB-11334] Unjoin a channel from a peer**
+
+The new command `peer node unjoin` enables an administrator to remove (unjoin) a channel from a peer.
+The peer must be stopped when the command is executed so that channel artifacts can be cleaned up.
+The channel's blockchain, state database, and associated entries will be removed from the peer.
+When the peer is restarted it will no longer receive blocks for the channel.
+
+Improvements
+------------
+
+**peer and orderer - Implement legacy name constraints verification for Go 1.15**
+
+These changes reproduce the Go 1.14 name constraint verification in the MSP.
+Without these changes, certificate chains that would fail verification in Go 1.14 would
+successfully validate in Go 1.15 due to the change mentioned in the [Go 1.15 release notes](https://golang.org/doc/go1.15#commonname).
+Specifically, if a signing certificate contains a name constraint, the leaf certificate
+does not include SAN extensions, and the leaf's common name looks like a host name,
+then the additional verification is performed to ensure deterministic behavior relative
+to prior Fabric releases.
+
+**peer and orderer - Default log record format improvements**
+
+Expanded the width of the log record sequence number to a minimum of four characters,
+moved the log sequence number and log level to the left,
+and added bold formatting to the function name.
+These changes keep the fixed-width columns together at the left
+and add a visual break between the logging module name and log message text.
+
+**peer - New configuration option to disable gossip block forwarding**
+
+If all peers in an organization explicitly set "peer.deliveryclient.blockGossipEnabled" to false,
+no peer in the organization gossips blocks to any other peer in that organization.
+Use this setting when all peers pull blocks from ordering service. For more
+information see deprecation announcement below: **FAB-15317: Block dissemination via gossip is deprecated**.
+
+**orderer - [FAB-18484] Return transaction forwarding result back to the client synchronously**
+
+With this improvement a Raft follower waits for the transaction to be forwarded to the Raft leader,
+and returns the result (success or failure) back to the client accordingly.
+Prior to this improvement, the Raft follower returned success after enqueueing it into the message queue,
+which might have resulted in the transaction being dropped but a success being returned to the client.
+Application clients should still monitor transaction commit events, since the Raft leader is not guaranteed
+to deliver the transaction into a block in exception scenarios, but this improvement avoids
+transactions from being dropped when there are connection issues between a Raft follower and Raft leader.
+
+**peer - Ability to override core.yaml chaincode.externalBuilders via environment variable**
+
+Since chaincode.externalBuilders is an array, it previously was not possible to set via environment variable override.
+It is now possible to override chaincode.externalBuilders using an environment variable
+using the format `CORE_CHAINCODE_EXTERNALBUILDERS=[{name: x, path: dir1}, {name: y, path: dir2}]`.
+
+
+Fixes
+-----
+All fixes as of v2.3.2 are included in v2.4.0-beta. Additionally, the following fixes are made in v2.4.0-beta.
+
+**orderer - [FAB-18521] Consenters' metadata is not replicated while OSN catches up with snapshot**
+
+If an ordering service node crashes while replicating blocks from another ordering service,
+the consenters metadata will not be available and the ordering service node will not be
+able to reconnect to the consenter set upon restart. This fix ensures that an ordering
+service node that is replicating blocks persists the consenters metadata so that it
+can reconnect to the consenter set.
+
+
+Dependencies
+------------
+Fabric v2.4.0-alpha has been tested with the following dependencies:
+* Go 1.15.7
+* CouchDB v3.1.1
+* Alpine images 3.13
+
+Deprecations (existing)
+-----------------------
+
+**FAB-15754: The 'Solo' consensus type is deprecated.**
+
+The 'Solo' consensus type has always been marked non-production and should be in
+use only in test environments, however for compatibility it is still available,
+but may be removed entirely in a future release.
+
+**FAB-16408: The 'Kafka' consensus type is deprecated.**
+
+The 'Raft' consensus type was introduced in v1.4.1 and has become the preferred
+production consensus type.  There is a documented and tested migration path from
+Kafka to Raft, and existing users should migrate to the newer Raft consensus type.
+For compatibility with existing deployments, Kafka is still supported,
+but may be removed entirely in a future release.
+Additionally, the fabric-kafka and fabric-zookeeper docker images are no longer updated, maintained, or published.
+
+**Fabric CouchDB image is deprecated**
+
+v2.2.0 added support for CouchDB 3.1.0 as the recommended and tested version of CouchDB.
+If prior versions are utilized, a Warning will appear in peer log.
+Note that CouchDB 3.1.0 requires that an admin username and password be set,
+while this was optional in CouchDB v2.x. See the
+[Fabric CouchDB documentation](https://hyperledger-fabric.readthedocs.io/en/v2.2.0/couchdb_as_state_database.html#couchdb-configuration)
+for configuration details.
+Also note that CouchDB 3.1.0 default max_document_size is reduced to 8MB. Set a higher value if needed in your environment.
+Finally, the fabric-couchdb docker image will not be updated to v3.1.0 and will no longer be updated, maintained, or published.
+Users can utilize the official CouchDB docker image maintained by the Apache CouchDB project instead.
+
+**FAB-7559: Support for specifying orderer endpoints at the global level in channel configuration is deprecated.**
+
+Utilize the new 'OrdererEndpoints' stanza within the channel configuration of an organization instead.
+Configuring orderer endpoints at the organization level accommodates
+scenarios where orderers are run by different organizations. Using
+this configuration ensures that only the TLS CA certificates of that organization
+are used for orderer communications, in contrast to the global channel level endpoints which
+would cause an aggregation of all orderer TLS CA certificates across
+all orderer organizations to be used for orderer communications.
+
+**FAB-17428: Support for configtxgen flag `--outputAnchorPeersUpdate` is deprecated.**
+
+The `--outputAnchorPeersUpdate` mechanism for updating anchor peers has always had
+limitations (for instance, it only works the first time anchor peers are updated).
+Instead, anchor peer updates should be performed through the normal config update flow.
+
+**FAB-15406: The fabric-tools docker image is deprecated**
+
+The fabric-tools docker image will not be published in future Fabric releases.
+Instead of using the fabric-tools docker image, users should utilize the
+published Fabric binaries. The Fabric binaries can be used to make client calls
+to Fabric runtime components, regardless of where the Fabric components are running.
+
+**FAB-15317: Block dissemination via gossip is deprecated**
+
+Block dissemination via gossip is deprecated and may be removed in a future release.
+Fabric peers can be configured to receive blocks directly from an ordering service
+node and not gossip blocks by using the following configuration:
+```
+peer.gossip.orgLeader: true
+peer.gossip.useLeaderElection: false
+peer.gossip.state.enabled: false
+peer.deliveryclient.blockGossipEnabled: false
+```
+
+**FAB-15061: Legacy chaincode lifecycle is deprecated**
+
+The legacy chaincode lifecycle from v1.x is deprecated and will be removed
+in a future release. To prepare for the eventual removal, utilize the v2.x
+chaincode lifecycle instead, by enabling V2_0 application capability on all
+channels, and redeploying all chaincodes using the v2.x lifecycle. The new
+chaincode lifecycle provides a more flexible and robust governance model
+for chaincodes. For more details see the
+[documentation for enabling the new lifecycle](https://hyperledger-fabric.readthedocs.io/en/release-2.2/enable_cc_lifecycle.html).