Sending Messages On Ethereum Testnets – Mailchain
Mailchain supports the Ethereum Mainnet and its testnets, Ropsten, Goerli, Kovan, and Rinkerby for sending message between Ethereum accounts. This article walks through the steps needed for developers to start sending messages on Ethereum testnets to test their application.
Each Mailchain message needs Gas for it to be included on the blockchain (see: What is Gas). The Gas requirement for each message sent on the Ethereum Mainnet is currently 30,660, which in today’s terms is around 0.00061 ETH or~$0.10.
When handling a message in development, developers tend to use one of the Ethereum testnets. This means they don’t need to spend Mainnet ETH, which has a real cost.
To send messages using Mailchain on a testnet, you will need an Ethereum address with a minimum balance of around 0.0007 ETH on that testnet.
NOTE! Ethereum addresses are valid on the Ethereum mainnet and all testnets, so it’s best to create a new address to use in development only. This means that if you make a mistake, lose a key, or if you accidentally expose a private key, only testnet ETH will be lost.
1. Create A New Ethereum Account Address For Testing/ Development
Follow the steps in either of the tools, but please take the time to write everything down that type or enter into fields. At the least, you’ll need to record a seed phrase (or private key) and password.
2. Get Some Test ETH
If using Metamask, you can switch to your desired testnet in the interface (see image), then go to https://faucet.metamask.io/ in your browser.
MyCrypto And Other Wallet Software
For other wallets and faucets, you usually don’t need to be connected to the testnet to request testnet ETH. Instead, you can head to one of the following faucets and follow the instructions to be sent some test ETH.
3. Install Mailchain
4. Open Your Mailchain Inbox
5. Switch To A Testnet
In the Mailchain Inbox, switch to the testnet that you want to send a message on (and have a balance on).
6. Compose and Send a Message
Click “COMPOSE” in the Inbox interface and send a message to an ethereum address which has already sent a transaction (see FAQs below for why), e.g. the Mailchain Developer address:
We love to receive messages from users. And tell us where you’re sending the message from!
Why can I only send a message to an Ethereum account which has already sent a transaction?
Mailchain encrypts messages by default so that only the recipient can view the message. It uses the public key for the recipient Ethereum account, which is can be determined in transaction details when sent by that Ethereum account.
So, if Alice wants to send a message to Bob, Bob needs to have created an Ethereum transaction at some point in the past (or sent a Mailchain message to anyone).
Can I send a message to myself?
If you have already sent a message or transaction, yes.
If you have not yet sent a message or transaction, Mailchain won’t be able to be able to determine your public key yet. Please send a nice message to `0x4ad2b251246aafc2f3bdf3b690de3bf906622c51` or send yourself 0 testnet ETH from your wallet (e.g. Metamask, Brave or MyCrypto).
Receive messages from other developers?
If you have sent a message or transaction on this testnet, you can receive messages from other developers, or send messages to yourself, from the same address or another development address.
Does Mailchain support ENS?
Yes. Because Mailchain supports ENS, you can configure an easy, human readable name for your development address on the testnet you are working on. This makes it easier to keep track when switching between different addresses.