Using terrad#

The following information explains the functions you can use from terrad, the command-line interface that connects to Terra and enables you to interact with the Terra blockchain. Every active validator and full node runs terrad and communicates with their node via terrad. In this relationship, terrad operates as both the client and the server. You can use terrad to interact with the Terra blockchain by uploading contracts, querying data, managing staking activities, working with governance proposals, and more. For more general information at the command line, run terrad --help. For more information about a specific terrad command, append the -h or --help flag after the command, such as terrad query --help.

Accessing a Node#

To query the state and send transactions, you must connect to a node, which is the access point to the entire network of peer connections. You can either run your own full node or connect to someone else’s.

Running your own full node#

Running your own full node is the most secure option, but it comes with relatively high resource requirements. For more information about the requirements to run your own full node and a tutorial for installing terrad, see installation. For a tutorial that explains how to connect to an existing Terra network, see joining a network.

Connecting to a remote full node#

If you don’t want to run your own full node, you can connect to someone else’s full node. As you consider your options for operators, prioritize operators you trust because malicious operators might intentionally return incorrect query results or censor your transactions. However, they will never be able to steal your funds because your private keys are stored locally on your computer or on your Ledger hardware device. Possible options of full-node operators include validators, wallet providers or exchanges.

To connect to the full-node, you need an address in the https://<host>:<port> format, for example https://77.87.106.33:26657. This address has to be communicated by the full-node operator you choose to trust. You will use this address in the following section.

If you are not running a node yet would like to communicate through terrad, lists of public nodes can be found here.

Configuring terrad#

terrad enables you to interact with the node that runs on the Terra network, whether you run it yourself or not. To configure terrad, edit the the config.toml file in the ~/.terra/config/ directory.

Querying Blockchain State#

To query all relevant information from the blockchain, such as like account balances, amount of bonded tokens, outstanding rewards, and so on, use terrad query. The following list shows some of the most useful commands for delegators:

# query account balances and other account-related information
terrad query account <ACCOUNT_ADDRESS>
# Account address is of the form terra1rEXAMPLE9tEXAMPLEf9cvEXAMPLEss
# you can find the one for your node by running `terrad keys list`

# query the list of validators
terrad query staking validators

# query the information of a validator given their address
terrad query staking validator <validatorAddress>

# query all delegations made from a delegator given their address
# (note: delegator addresses are regular account addresses)
terrad query staking delegations <delegatorAddress>

# query a specific delegation made from a delegator to a validator
terrad query staking delegation <delegatorAddress> <validatorAddress>

# query the rewards of a delegator given a delegator address (e.g. terra10snjt8dmpr5my0h76xj48ty80uzwhraqalu4eg)
terrad query distr rewards <delegatorAddress>

Sending Transactions#

To interact with the blockchain by sending transactions containing module messages with state-changing directives that get processed and included in blocks, use terrad tx. All of transaction-sending operations follow the form:

terrad tx ...

To learn more about the different types of interactions you can issue, see the section for each module.

Simulating a transaction#

To simulate a transaction without actually broadcasting it, append the --dry-run flag to the command statement:

terrad tx bank send \
    <sender_address> \
    <recipient_address> \
    <amount_and_denomination> \
    --chain-id=<chain-id> \
    --dry-run
Example: simulate a KRW transfer:
terrad tx bank send \
    terra1ru2ySENDER-EXAMPLEtf9cva9kp33h0jnsm9ss \  
    terra1rRECIPIENT-EXAMPLEtf9cva9kp33h0jnsm9ss \
    1ukrw \
    --chain-id=bombay-12 \
    --dry-run

Generating a transaction without sending#

To build a transaction and print its JSON format to STDOUT, append --generate-only to the list of the command line arguments. This allows you to separate the creation and signing of a transaction with the broadcasting.

terrad tx bank send \
    <sender_address> \
    <recipient_address> \
    <amount_and_denomination> \
    --chain-id=<chain-id> \
    --generate-only > unsignedSendTx.json
terrad tx sign \
    --chain-id=<chain_id> \
    --from=<address> \
    unsignedSendTx.json > signedSendTx.json
Example: Sign an unsigned transaction
terrad tx sign \
    --chain-id=bombay-12 \
    --from=terra1EXAMPLEy09tEXAMPLEtf9EXAMPLE3h0EXAMPLEss unsignedTx.json

A healthy response should looks simillar to the following:

{
  "body": {
    "messages": [
      {
        "@type": "/cosmos.bank.v1beta1.MsgSend",
        "from_address": "terra1ru2ySENDER-EXAMPLEtf9cva9kp33h0jnsm9ss",
        "to_address": "terra1rRECIPIENT-EXAMPLEtf9cva9kp33h0jnsm9ss",
        "amount": [
          {
            "denom": "ukrw",
            "amount": "1"
          }
        ]
      }
    ],
    "memo": "",
    "timeout_height": "0",
    "extension_options": [],
    "non_critical_extension_options": []
  },
  "auth_info": {
    "signer_infos": [
      {
        "public_key": {
          "@type": "/cosmos.crypto.secp256k1.PubKey",
          "key": "A3Z50zDpCEXAMPLEG5Ru+DGOFEXAMPLEm0EXAMPLEKtxd"
        },
        "mode_info": {
          "single": {
            "mode": "SIGN_MODE_DIRECT"
          }
        },
        "sequence": "0"
      }
    ],
    "fee": {
      "amount": [],
      "gas_limit": "200000",
      "payer": "",
      "granter": ""
    }
  },
  "signatures": [
    "dclBjQ9IsPPkOlcFMsBlQqkx7yqRl0oPBnRuEXAMPLEwlSQTGndiJtZMXI7j5MZ+5JEZI0X3MOg0cr72sq11lA=="
  ]
}

You can validate the transaction’s signatures by typing the following:

terrad tx sign --validate-signatures signedSendTx.json

You can broadcast the signed transaction to a node by providing the JSON file to the following command:

terrad tx broadcast --node=<node> signedSendTx.json

Fees#

Transactions on the Terra Protocol network need to include a transaction fee in order to be processed. This fee pays for the gas required to run the transaction. The formula is the following:

\[fees = gas * gasPrices\]

The gas is dependent on the transaction. Different transaction require different amount of gas. The gas amount for a transaction is calculated as it is being processed, but there is a way to estimate it beforehand by using the auto value for the gas flag. Of course, this only gives an estimate. You can adjust this estimate with the flag --gas-adjustment (default 1.0) if you want to be sure you provide enough gas for the transaction.

The gasPrice is the price of each unit of gas. Each validator sets a min-gas-price value, and will only include transactions that have a gasPrice greater than their min-gas-price.

The transaction fees are the product of gas and gasPrice. As a user, you have to input 2 out of 3. The higher the gasPrice/fees, the higher the chance that your transaction will get included in a block.

Setting Fees#

Each transaction may either supply fees or gas prices, but not both. Most users will typically provide fees as this is the final cost you will end up incurring for the transaction being included in the ledger, where as gas prices will be dynamically calculated depending on the validator.

Validators specify a minimum gas price that they use to determine whether to include a transaction, which they calculate during CheckTx, where gasPrices >= minGasPrices. Note, your transaction must supply fees that are greater than or equal to any of the denominations the validator requires.

Validators may start to prioritize transactions by gasPrice in the mempool, so providing higher fees or gas prices will likely yield higher priority of inclusion in a block.

To directly use fees:

terrad tx send ... --fees=100000uluna

If you use fees, validators will calculate the implied minGasPrices by dividing your fee with the estimated gas consumption, to properly assign the right priority to your transaction.

To use gas prices (use a comma-separated list of amount and denominations).

terrad tx send ... --gas-prices=0.15uusd

Taxes#

Taxes in Terra must be included in the fee amount. Users can make transactions with existing methods without the --fees flag but with gas prices flag. This will automatically calculate the tax and return fees in addition to the existing gas fees.

Automatic Fee Estimation#

You may want to cap the maximum gas that can be consumed by the transaction via the --gas flag. If you pass --gas=auto, the gas will be automatically estimated before executing the transaction.

Gas estimate might be inaccurate as state changes could occur in between the end of the simulation and the actual execution of a transaction, thus an adjustment is applied on top of the original estimate in order to ensure the transaction is broadcasted successfully.

The adjustment can be controlled via the --gas-adjustment flag, whose default value is 1.0.

To get a direct fee estimation from terrad:

terrad tx estimate-fee ...\
    --gas-prices=0.15uusd
    --gas-adjustment=1.4

To create and send transactions using fee-estimation, use the template below as a format:

terrad tx send ... \
    --gas-prices=0.15uusd
    --gas=auto
    --gas-adjustment=1.4

Shell Autocompletion#

Auto-completion scripts for popular UNIX shell interpreters such as bash and zsh can be generated through the completion command, which is available for both terrad and terrad. This allows for a more convenient way to interact with the Terra Core endpoints when using the command-line.

If you want to generate bash completion scripts run the following command:

terrad completion > terrad_completion
terrad completion > terrad_completion

If you want to generate zsh completion scripts run the following command:

terrad completion --zsh > terrad_completion
terrad completion --zsh > terrad_completion

On most UNIX systems, such scripts may be loaded in .bashrc or .bash_profile to enable Bash autocompletion.

echo '. terrad_completion' >> ~/.bashrc
echo '. terrad_completion' >> ~/.bashrc

Refer to the user’s manual of your interpreter provided by your operating system for information on how to enable shell autocompletion.