GSoC: Qaul Matrix Bridge relay bot implementation

Hello there ! I have already published a blog post where you can learn about what is Qaul and why currently it needs a matrix bridge ? You can read about it here : GSoC Project blog Qaul Matrix bridge

Getting Started

Initially we thought that we would run matrix bridge as a daemon process and use Go Lang to create the bridge. But, My mentor has a friend working in element, which is a matrix client, suggested us that since the world is taking on for the Rust, Matrix-SDK are actively written in Rust and there is something called as RuMa which stands for Rust Matrix. RuMa is an amazing work and thus, We have decided to do it in rust only because our Qaul has its entire backend in Rust.

Knowing the toolkits

I had read and researched through the RuMa and Matrix-SDK-Rust projects since this is now the part which we will be using for our project instead of GoLang.

Mentor suggested that I should duplicate the qaul-cli binary and tweak it in whatever way I would need to in order to work on it. Here is the main reason why we chose the qaul-cli specifically for implementing the bridge concept.

  • It already has two workers set in place which will check for any activity on entire qaul network each 10ms.
  • We have access to CLI which we use to interact with RPC protocol and protobuff messaging.

I was reading through the documentation of the matrix-sdk crate and what I found was a beautifully commented codes for creating the bot inside examples/ directory. They were really helpful for me to initiate the coding part.

Planning the bridge

Version 0

[On Matrix]

  1. Create a bot account for Qaul and specify a server to work on.
  2. Invite the bot to the testing matrix room.

[On Qaul]

  1. Create a binary copy of qaul-cli
  2. Code the logic to login our bot into the matrix room as soon as the qaul-cli binary is running.
  3. Also Code a basic testing functionality (For Eg : Call it !ping command)

[On Matrix]

  1. Login with our personal account [@harshil1] and send a message with !ping in the room.
  2. In response we should receive all the nodes connected to the network.

Version 1

Instead of just an echo as response, We should pick the messages from both the ends. Send “Hi” from qaul and it should first sense in matrix without our personal human activity that there is some event triggered in qaul. Once event is detected, the message should show up into the matrix room.

Next we can reverse engineer the above feature and do the same in qaul by sending a message in matrix room.

Version 2

This just follows the Version 1 functionality wise but this should be implemented for 1-on-1 direct messages. In matrix and qaul both, private DMs are nothing but a group with only two members. We need to create a use case where we can send the message in groups by inviting a bot and the bot invite the user on other application and rest remains same.

Version 2+

After the above completions, We can think of double puppeting the bot so now our bot is not just qaul-bridge but a real username from the qaul node.

Progress till Mid Evaluation

We have built end to end Matrix to Qaul bridge working as expected for Version 1 and will be achieving the Version 2 within next week. Speaking in-depth about version 2, We already have a functionality to check if there is any new group requiring to connect with a matrix user and accordingly the Qaul-Bot opens Matrix room and invites wanter Matrix user. Then Matrix user is able to send messages into the qaul group. We are supposed to close the part where a message goes from Qaul into the Matrix.


If you are interested in learning our code for the bridge, I am writing a book where I have explained an approach to integrate the bridge in qaul world and it has organized chapters with snippets. For more, You can also refer to my raised Pull Request and It will give more clear insights.

Link to Book : GSoC 2.0 Journey Book – By Harshil Jani

Link to Pull Request : qaul/

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