Join the Testnet
::: warning You need to install spend before you go further :::
Setting Up a New Node
These instructions are for setting up a brand new full node from scratch.
First, initialize the node and create the necessary config files:
spend init <your_custom_moniker>
::: warning Note Monikers can contain only ASCII characters. Using Unicode characters will render your node unreachable. :::
You can edit this
moniker later, in the
# A custom human readable name for this node moniker = "<your_custom_moniker>"
You can edit the
~/.spend/config/spend.toml file in order to enable the anti spam mechanism and reject incoming transactions with less than the minimum gas prices:
# This is a TOML config file. # For more information, see https://github.com/toml-lang/toml ##### main base config options ##### # The minimum gas prices a validator is willing to accept for processing a # transaction. A transaction's fees must meet the minimum of any denomination # specified in this config (e.g. 10ustaking). minimum-gas-prices = ""
Your full node has been initialized!
Genesis & Seeds
Copy the Genesis File
Fetch the testnet's
genesis.json file into
spend's config directory.
mkdir -p $HOME/.spend/config curl https://raw.githubusercontent.com/Spend/Spendchain/master/genesis/genesis.json > $HOME/.spend/config/genesis.json
To verify the correctness of the configuration run:
Add Seed Nodes
Your node needs to know how to find peers. You'll need to add healthy seed nodes to
For more information on seeds and peers, you can read this.
A Note on Gas and Fees
On Spend Hub testnet, the accepted denom is
1staking = 1.000.000ustaking
Transactions on the Spend Hub 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 = ceil(gas * gasPrices)
gas is dependent on the transaction. Different transaction require different amount of
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
1.0) if you want to be sure you provide enough
gas for the transaction.
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
fees are the product of
gasPrice. As a user, you have to input 2 out of 3. The higher the
fees, the higher the chance that your transaction will get included in a block.
For testnet, the recommended
Your full-node keeps unconfirmed transactions in its mempool. In order to protect it from spam, it is better to set a
minimum-gas-prices that the transaction must meet in order to be accepted in your node's mempool. This parameter can be set in the following file
The initial recommended
0.025ustaking, but you might want to change it later.
Run a Full Node
Start the full node with this command:
Check that everything is running smoothly:
View the status of the network with the Spend Explorer.
Spend can dump the entire application state to a JSON file, which could be useful for manual analysis and can also be used as the genesis file of a new network.
Export state with:
spend export > [filename].json
You can also export state from a particular height (at the end of processing the block of that height):
spend export --height [height] > [filename].json
If you plan to start a new network from the exported state, export with the
spend export --height [height] --for-zero-height > [filename].json
Help to prevent a catastrophe by running invariants on each block on your full node. In essence, by running invariants you ensure that the state of testnet is the correct expected state. One vital invariant check is that no stakings are being created or destroyed outside of expected protocol, however there are many other invariant checks each unique to their respective module. Because invariant checks are computationally expensive, they are not enabled by default. To run a node with these checks start your node with the assert-invariants-blockly flag:
spend start --assert-invariants-blockly
If an invariant is broken on your node, your node will panic and prompt you to send a transaction which will halt testnet. For example the provided message may look like:
invariant broken: loose token invariance: pool.NotBondedTokens: 100 sum of account tokens: 101 CRITICAL please submit the following transaction: spendcli tx crisis invariant-broken staking supply
When submitting a invariant-broken transaction, transaction fee tokens are not deducted as the blockchain will halt (aka. this is a free transaction).
Upgrade to Validator Node
You now have an active full node. What's the next step? You can upgrade your full node to become a Spend Validator. The top 100 validators have the ability to propose new blocks to the Spend Hub. Continue onto the Validator Setup.