corda/docs/source/release-notes.rst

Release notes

Here are release notes for each snapshot release from M9 onwards.

Unreleased

Writing CorDapps has been made simpler by removing boiler-plate code that was previously required when registering flows. Instead we now make use of classpath scanning to automatically wire-up flows.

There are major changes to the Party class as part of confidential identities, and how parties and keys are stored in transaction state objects. See changelog for full details.

We've added the ability for flows to be versioned by their CorDapp developers. This enables a node to support a particular version of a flow and allows it to reject flow communication with a node which isn't using the same fact. In a future release we allow a node to have multiple versions of the same flow running to enable backwards compatibility.

Milestone 11

Special thank you to Gary Rowe for his contribution to Corda's Contracts DSL in M11.

Work has continued on confidential identities, introducing code to enable the Java standard libraries to work with composite key signatures. This will form the underlying basis of future work to standardise the public key and signature formats to enable interoperability with other systems, as well as enabling the use of composite signatures on X.509 certificates to prove association between transaction keys and identity keys.

The identity work will require changes to existing code and configurations, to replace party names with full X.500 distinguished names (see RFC 1779 for details on the construction of distinguished names). Currently this is not enforced, however it will be in a later milestone.

• "myLegalName" in node configurations will need to be replaced, for example "Bank A" is replaced with "CN=Bank A,O=Bank A,L=London,C=UK". Obviously organisation, location and country ("O", "L" and "C" respectively) must be given values which are appropriate to the node, do not just use these example values.
• "networkMap" in node configurations must be updated to match any change to the legal name of the network map.
• If you are using mock parties for testing, try to standardise on the DUMMY_NOTARY, DUMMY_BANK_A, etc. provided in order to ensure consistency.

We anticipate enforcing the use of distinguished names in node configurations from M12, and across the network from M13.

We have increased the maximum message size that we can send to Corda over RPC from 100 KB to 10 MB.

The Corda node now disables any use of ObjectInputStream to prevent Java deserialisation within flows. This is a security fix, and prevents the node from deserialising arbitrary objects.

We've introduced the concept of platform version which is a single integer value which increments by 1 if a release changes any of the public APIs of the entire Corda platform. This includes the node's public APIs, the messaging protocol, serialisation, etc. The node exposes the platform version it's on and we envision CorDapps will use this to be able to run on older versions of the platform to the one they were compiled against. Platform version borrows heavily from Android's API Level.

We have revamped the DemoBench user interface. DemoBench will now also be installed as "Corda DemoBench" for both Windows and MacOSX. The original version was installed as just "DemoBench", and so will not be overwritten automatically by the new version.

Milestone 10

Special thank you to Qian Hong, Marek Skocovsky, Karel Hajek, and Jonny Chiu for their contributions to Corda in M10.

A new interactive Corda Shell has been added to the node. The shell lets developers and node administrators easily command the node by running flows, RPCs and SQL queries. It also provides a variety of commands to monitor the node. The Corda Shell is based on the popular CRaSH project and new commands can be easily added to the node by simply dropping Groovy or Java files into the node's shell-commands directory. We have many enhancements planned over time including SSH access, more commands and better tab completion.

The new "DemoBench" makes it easy to configure and launch local Corda nodes. It is a standalone desktop app that can be bundled with its own JRE and packaged as either EXE (Windows), DMG (MacOS) or RPM (Linux-based). It has the following features:

1. New nodes can be added at the click of a button. Clicking "Add node" creates a new tab that lets you edit the most important configuration properties of the node before launch, such as its legal name and which CorDapps will be loaded.
2. Each tab contains a terminal emulator, attached to the pseudoterminal of the node. This lets you see console output.
3. You can launch an Corda Explorer instance for each node at the click of a button. Credentials are handed to the Corda Explorer so it starts out logged in already.
4. Some basic statistics are shown about each node, informed via the RPC connection.
5. Another button launches a database viewer in the system browser.
6. The configurations of all running nodes can be saved into a single .profile file that can be reloaded later.

Soft Locking is a new feature implemented in the vault to prevent a node constructing transactions that attempt to use the same input(s) simultaneously. Such transactions would result in naturally wasted effort when the notary rejects them as double spend attempts. Soft locks are automatically applied to coin selection (eg. cash spending) to ensure that no two transactions attempt to spend the same fungible states.

The basic Amount API has been upgraded to have support for advanced financial use cases and to better integrate with currency reference data.

We have added optional out-of-process transaction verification. Any number of external verifier processes may be attached to the node which can handle loadbalanced verification requests.

We have also delivered the long waited Kotlin 1.1 upgrade in M10! The new features in Kotlin allow us to write even more clean and easy to manage code, which greatly increases our productivity.

This release contains a large number of improvements, new features, library upgrades and bug fixes. For a full list of changes please see changelog.

Milestone 9

This release focuses on improvements to resiliency of the core infrastructure, with highlights including a Byzantine fault tolerant (BFT) decentralised notary, based on the BFT-SMaRT protocol and isolating the web server from the Corda node.

With thanks to open source contributor Thomas Schroeter for providing the BFT notary prototype, Corda can now resist malicious attacks by members of a distributed notary service. If your notary service cluster has seven members, two can become hacked or malicious simultaneously and the system continues unaffected! This work is still in development stage, and more features are coming in the next snapshot!

The web server has been split out of the Corda node as part of our ongoing hardening of the node. We now provide a Jetty servlet container pre-configured to contact a Corda node as a backend service out of the box, which means individual webapps can have their REST APIs configured for the specific security environment of that app without affecting the others, and without exposing the sensitive core of the node to malicious Javascript.

We have launched a global training programme, with two days of classes from the R3 team being hosted in London, New York and Singapore. R3 members get 5 free places and seats are going fast, so sign up today.

We've started on support for confidential identities, based on the key randomisation techniques pioneered by the Bitcoin and Ethereum communities. Identities may be either anonymous when a transaction is a part of a chain of custody, or fully legally verified when a transaction is with a counterparty. Type safety is used to ensure the verification level of a party is always clear and avoid mistakes. Future work will add support for generating new identity keys and providing a certificate path to show ownership by the well known identity.

There are even more privacy improvements when a non-validating notary is used; the Merkle tree algorithm is used to hide parts of the transaction that a non-validating notary doesn't need to see, whilst still allowing the decentralised notary service to sign the entire transaction.

The serialisation API has been simplified and improved. Developers now only need to tag types that will be placed in smart contracts or sent between parties with a single annotation... and sometimes even that isn't necessary!

Better permissioning in the cash CorDapp, to allow node users to be granted different permissions depending on whether they manage the issuance, movement or ledger exit of cash tokens.

We've continued to improve error handling in flows, with information about errors being fed through to observing RPC clients.

There have also been dozens of bug fixes, performance improvements and usability tweaks. Upgrading is definitely worthwhile and will only take a few minutes for most apps.

For a full list of changes please see changelog.