16 January 2019
IOHK newsletters provide updates on work done specifically for cryptocurrency exchanges and on relevant software releases and developments. The previous newsletter can be found here.
We are currently working on a few bug fixes in a Cardano 1.4.1 hotfix release that consists of Cardano 2.0.1 and Daedalus 0.12.1. After the Cardano 1.4.0 release it was discovered that some transactions with a high number of inputs would fail, and that validation for the maximum transaction fee was too strict - both of these issues have been fixed. Cardano 1.4.1 will be released soon. We recommend upgrading to this - Cardano 1.4.1, or a later Cardano 1.4 version as soon as possible after its release. Before upgrading, shut down the wallet and make a backup of the state directory; consult the exchange onboarding doc for build instructions.
With the optimized block storage introduced in Cardano SL 2.0.0, the node will begin a process to consolidate block files at startup, and users will notice increased I/O and CPU usage on their systems while block consolidation is in progress. If there are missing or corrupted block files in the database, the block consolidation process will not complete, and any wallet restoration will not complete. The current solution to this problem is to delete the database and re-sync blockchain data. We are working on adding verification of user instance of the blockchain and automation of its re-download in future releases.
As part of the Cardano 1.4.0 delivery, and our commitment to our partners, exchanges, and users, the Cardano delivery team released Cardano Testnet,where new features can be safely tested. We encourage all users to experiment with the new Cardano wallet on the testnet before upgrading.
Cardano Wallet API
Cardano 1.4 contains both versions of the Cardano Wallet API:
- V0 with the old data layer, that is deprecated, and
- V1 with the new data layer that becomes the default version.
One of the aims of this release is to provide a smooth transition from the old data layer to the new one. In the next Cardano release - Cardano 1.5, the old data layer will be removed entirely. Therefore we are calling for all exchanges to upgrade to Cardano 1.4 and migrate to Wallet V1 API. We will communicate the provisional date of the next release as soon as it is scheduled. If upgrading from Cardano 1.3 to Cardano 1.5 clients will lose wallet metadata, which will not happen if upgrading from 1.3 to 1.4 and then from 1.4 to 1.5.
Note. that between each update, exchanges are expected to start nodes in order to allow the migration process to begin. The migration itself is a fairly quick procedure (seconds to a few minutes) which should not be interrupted; it will eventually trigger a full wallet asynchronous restoration. The asynchronous restoration can be interrupted and restarted as usual without any consequences.
Cardano Wallet V1 API
We would like to draw exchanges’ attention to Backwards Incompatible Changes In Cardano 1.4 Wallet API; the blog provides the details. If any of the enumerated endpoints are used in exchanges’ integration tier then the Cardano Wallet team recommends code review and amendment due to the improved logic in Cardano 1.4 if required.
Cardano Byron EOL
The first Cardano development phase, Byron, is approaching its end of life this year. There will be a few more releases of Cardano 1.N, and two hard forks before Cardano will be upgraded to Cardano Shelley, which will mark the beginning of decentralized Cardano 2.N. In this blog we explain Cardano development phases as well as Cardano versioning.
If an exchange has an explicit feature request for the wallet API, or the wallet in general, and would like to work with us, please contact us either via an already established communication channel, or email your suggestion to email@example.com with the subject ‘New Feature Request’. Our engineers, product managers, and business analysts will consider your proposal. IOHK also has Support portal where requests can be submitted.