POC - Mithril signature diffusion with a "fake Cardano network layer"

[Alenar]

Content

This PR is a proof a concept of a decentralized message queue to diffuse Mithril signatures.

Since the protocol that will be used for signature diffusion through the Cardano node is still on the design phase, we simulate it with the creation of a new binary signature-network-node:

• Nodes have an Unix socket were you can register signatures (using http) and pull the available signatures known by the node.
• Nodes have an input directory were json serialized signatures can be put, it will be then added to the node available signatures.
• Nodes share the signatures that are registered to them by writing them as json in their peers input directory.
• Registered signatures can be pulled by calling a pull-signatures route on the node unix socket.

mithril-signer signature registration is abstracted with a new trait, SignaturePublisher, that have two implementations. One is the previous behavior communicating directly to the aggregator using http, the other foward signatures thought a signature-network-node unix socket.

mithril-aggregator have a new thread that pulls signatures constantly using the pull-signatures route of a signature-network-node unix socket and register them using the certifier-service the same way as its http server does.

mithil-end-to-end have been adapted to spawn one signature-network-node per mithril node.

Comments

🛑 DO NOT MERGE: 🛑 This PR should not be merged as it is intended for experimentation only.

As this is a POC several shortcuts were used:

• signature-network-node stores registered signatures indefinitely until their pull-signatures route is called, meaning it's possible to make them crash by overloading their memory.
• Tests were written but they are not exhaustive.
• Windows isn't compatible.

Issue(s)

Relates to #1837

[github-actions]

Test Results

    3 files   -  1     49 suites   - 6   10m 31s ⏱️ +6s
1 410 tests +15  1 410 ✅ +15  0 💤 ±0  0 ❌ ±0 
1 554 runs   - 55  1 554 ✅  - 55  0 💤 ±0  0 ❌ ±0 

Results for commit 8c3cdcd. ± Comparison against base commit 63e1204.

♻️ This comment has been updated with latest results.

[jpraynaud]

Good work 💪