This document is a tutorial on how to run the chat2 application in the spam-protected mode using the Waku-RLN-Relay protocol and with dynamic/on-chain group management.
In the on-chain/dynamic group management, the state of the group members i.e., their identity commitment keys is moderated via a membership smart contract deployed on the Sepolia network which is one of the Ethereum test-nets.
1. An rln keystore file with credentials to the rln membership smart contract you wish to use. You may obtain this by registering to the smart contract and generating a keystore, or by using the [rln-keystore-generator](./rln-keystore-generator.md) which does that for you.
The test fleets will act as routers and are also set to run Waku-RLN-Relay over the same pubsub topic and content topic as chat2 clients i.e., the default pubsub topic of `/waku/2/default-waku/proto` and the content topic of `/toy-chat/3/mingde/proto`.
For `rln-relay-eth-client-address`, if you do not know how to obtain it, you may use the following tutorial on the [prerequisites of running on-chain spam-protected chat2](./pre-requisites-of-running-on-chain-spam-protected-chat2.md).
just make sure that you increment the `--ports-shift` value for each new client you set up e.g., `--ports-shift=2`.
Once you run the command, you are asked to choose your nickname:
```
Choose a nickname >> Alice
```
then you will see a couple of other messages related to setting up the connections of your chat app,
the content may differ on your screen though:
```
Connecting to test fleet using DNS discovery...
Discovered and connecting to @[16Uiu2HAkvWiyFsgRhuJEb9JfjYxEkoHLgnUQmr1N5mKWnYjxYRVm, 16Uiu2HAmPLe7Mzm8TsYUubgCAW1aJoeFScxrLj8ppHFivPo97bUZ, 16Uiu2HAmJb2e28qLXxT5kZxVUUoJt72EMzNGXB47Rxx5hw3q4YjS]
your RLN identity key is: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
your RLN identity commitment key is: 6c6598126ba10d1b70100893b76d7f8d7343eeb8f5ecfd48371b421c5aa6f012
```
Finally, the chat prompt `>>` will appear which means your chat2 client is ready.
Once you type a chat line and hit enter, you will see a message that indicates the epoch at which the message is sent e.g.,
```
>> Hi
--rln epoch: 165886530
<Jul26,12:55> Alice: Hi
```
The numerical value `165886530` indicates the epoch of the message `Hi`.
You will see a different value than `165886530` on your screen.
If two messages sent by the same chat2 client happen to have the same RLN epoch value, then one of them will be detected as spam and won't be routed (by test fleets in this test setting).
At the time of this tutorial, the epoch duration is set to `10` seconds.
You can inspect the current epoch value by checking the following [constant variable](https://github.com/waku-org/nwaku/blob/44c543129ee4149255a00a05f1e7d21f8fa28626/waku/v2/waku_rln_relay/constants.nim#L51) in the nim-waku codebase.
Your messages will be routed via test fleets that are running in spam-protected mode over the same content topic i.e., `/toy-chat/3/mingde/proto` as your chat client.
The two chat clients namely `Alice` and `Bob` are connected to the test fleets.
`Alice` sends 4 messages i.e., `message1`, `message2`, `message3`, and `message4`.
However, only three of them reach `Bob`.
This is because the two messages `message2` and `message3` have identical RLN epoch values, so, one of them gets discarded by the test fleets as a spam message.
The test fleets do not relay `message3` further, hence `Bob` never receives it.
You can check this fact by looking at `Bob`'s console, where `message3` is missing.
Discovered and connecting to @[16Uiu2HAkvWiyFsgRhuJEb9JfjYxEkoHLgnUQmr1N5mKWnYjxYRVm, 16Uiu2HAmPLe7Mzm8TsYUubgCAW1aJoeFScxrLj8ppHFivPo97bUZ, 16Uiu2HAmJb2e28qLXxT5kZxVUUoJt72EMzNGXB47Rxx5hw3q4YjS]
Discovered and connecting to @[16Uiu2HAkvWiyFsgRhuJEb9JfjYxEkoHLgnUQmr1N5mKWnYjxYRVm, 16Uiu2HAmPLe7Mzm8TsYUubgCAW1aJoeFScxrLj8ppHFivPo97bUZ, 16Uiu2HAmJb2e28qLXxT5kZxVUUoJt72EMzNGXB47Rxx5hw3q4YjS]
