Ultimately, smart contracts should be run on the blockchain. Once your smart contract is complete, it’s time to deploy your contract to a blockchain. Deploying a contract has a few pre-requisites:
The client software communicates with the network to transmit your deployments to the network. Clients exist for a variety of development platforms such as Python and Javascript. The official client is the Python Client It is also possible to create a client to meet specific needs as well.
It’s possible to use pre-built binaries or build from source. Both provide the casperLabs-client.
Ensure that your client matches the version of the network you intend to deploy to.
Python: casperlabs-client
Instructions
Make sure you have pre-requisites installed and you can build the casperlabs-client from source. If you build from source, you will need to add the build directories to your PATH.
Or, you can run the client commands from the root directory of the repo, using explicit paths to the binaries.
Blockchains are supported by infrastructure providers called “Validators”. To use the Validator infrastructure, it’s necessary to acquire token to pay for deployments (transactions).
When sending a deploy, the client needs to know which host will receive the deployment. The host parameter is either a DNS name or IP address of the host.
Blockchains use private key encryption to sign transactions. The private key used to sign the deployment must be the private key of the account that is being used to pay for the transaction.
CasperLabs supports complex deployments. To learn more about what is possible visit GitHub.
The easiest way to deploy a contract is to use an existing public network. CasperLabs provides a Testnet for this.
Go to CasperLabs Clarity and create an account.
Place your private key in a location that you can access during the deployment.
Request tokens from the faucet to fund your account.
The Testnet is operated by external validators that can accept transactions at the following endpoints:
deploy.casperlabs.io
18.219.70.138
62.171.172.72
52.88.90.57
116.203.69.88
35.158.200.94
The default port is 40401
There is an official Python client.
To check the client version run:
pip show casperlabs_client
If you want to send your deployments to an external network, use the latest released version of the client. If you are working off of dev, build the client locally and check the gitHash.
As described above, a basic deployment must provide some essential information. Here is an example deployment using the Python client that will work with the basic contract we created using the Contracts SDK for Rust:
casperlabs_client --host deploy.casperlabs.io deploy \ --session contract.wasm \ --session-args '[{"name": "surname", "value": {"string_value": "Nakamoto"}}]' \ --private-key account-private.pem \ --payment-amount 10000000
If your deployment works, expect to see a success message that looks like this:
Success! Deploy 8428717f1cfc9cc5c047f503661e9c0fc2a495ead44305a807bead130cbd181f deployed
Note: Each deploy gets a unique hash. This is part of the cryptographic security of blockchain technology. No two deploys will ever return the same hash.
The process of sending a deployment is separate from the processing of the contract by the system. Deployments queue up in the system before being added to a block. Therefore, it’s important to check the status of the deployment. For example, if an incorrect key is used to sign the deployment, it’s possible that the deploy does not process on the network, in spite of a successful deploy message. Deploy statuses can also be checked in the Clarity Explorer and also by the client.
casperlabs_client --host deploy.casperlabs.io show-deploy \ 8428717f1cfc9cc5c047f503661e9c0fc2a495ead44305a807bead130cbd181f deploy { deploy_hash: "8428717f1cfc9cc5c047f503661e9c0fc2a495ead44305a807bead130cbd181f" ... cost: 126165 } status { state: PROCESSED }
You can use the client’s method query-state to see a specific named key of the account. It works the same as the query method from the testing framework.
query-state
query
casperlabs_client --host deploy.casperlabs.io query-state \ --block-hash "f21fc0763279ad8349b0c0fce08e1ed678412d5e234a92e3063d4d5a35ee0739" \ --type address \ --key "0cc94662d68bd71b03083e38094f0b0e07a1bbb485969b6e68f21f4577fe928a" \ --path "special_value" string_value: "Nakamoto"