BGL-WBGL golang bridge implementation

Bridge service arhitecture:

1. Block scanner Eth / Bsc / other EVM networks
   • check incoming transfers and put sending to worker queue;
2. Block scanner BGL
   • check incoming transfers and put sending WBGL to worker queue;
3. Sending worker BGL / EVM
4. Manage address
5. TODO: Dashboard / Display status (by address or tx id)

Data structures:

1. address book: mapping BGL -> EVM WBGL, EVM BGL -> BGL and vice versa;

2. transaction history, status

   • pending (receiving tx detected)

   • sent (output tx sent)

   • success (output tx processed)

   • returned no funds output chain

   • returned no funds for gas output chain

   • unknown route (don't know destination to match sender address to)

   • fail (technical error occured, fail to return, etc.)

as resources are super-constrained (so no infrastructure expenses), should be runnable on something like micro instance (1vCPU/512Mb RAM);

• monolithic, no docker, no docker-compose golang service;

  • statically served HTML app (by the same binary);
  • API service;
  • block scanners and tx sending workers;

• BGL node (to have reliable RPC, probably remote could be used if needed);

• Redis (as compact local persistence engine);

  • no SQL queries, simple key-value

• round-robin on EVM RPCs (to use freely available);

• compatible by request/response to keep existing bridge webapp working with mininal changes;