Mosoly Ledger bridge

• Development
  • Setting up ledger bridge cache DB
  • Re-creating database
• Run the application
• Lint & build
• Metrics and debug counters

Development

In order to locally develop mosoly ledger bridge sync some of the pre-requisites needs to be setup:

• Golang 1.12 runtime for building and running the instance. Install one from golang.org
• Docker. Follow the Docker get started guide in order to install it

Setting up ledger bridge cache DB

A Docker image will be running Postgres DB instance. In order to make sure that our DB is persisted between shutdowns we must create a folder for storing DB files.

mkdir -p $HOME/docker/volumes/postgres

After persisted storage is prepare we will run A Docker image and map the folder for the DB files

docker run --rm \
  --name pg-docker \
   -e POSTGRES_USER=mosoly \
   -e POSTGRES_DB=ledger_bridge_cache \
   -e POSTGRES_PASSWORD=qwerty123456 \
   -d -p 45433:5432 \
   -v "${HOME}/docker/volumes/postgres:/var/lib/postgresql/data" \
   postgres

By running this command you will:

1. spin a new Postgres instance
2. create a database called ledger_bridge_cache
3. create a user mosoly with password qwerty123456
4. map /var/lib/postgresql/data folder to your local persisted storage $HOME/docker/volumes/postgres
5. Expose port 45433 to your local environment in order to access the DB

The following are default configuration on the mosoly-ledger-bridge and are a part of config/config.go. NOTE! default values should not be used in production environment and we strongly recommend to run a virtual machine for running a DB instance to minimize any potential latency issues.

After PostgreSQL is confirmed to be running connect to the instance and execute and create a schema that can be found in db/schema.sql file.

Re-creating database

If you ever need to re-create the database you will need to execute db/drop.sql to wipe data and tables after that you can re-create schema from db/schema.sql

Before running the script agains the database, please enter most recent value for latest_processed_block_number in query INSERT INTO ethereum_blockchain .... If running Ropsten testnet use the latest block number from https://ropsten.etherscan.io/. If running Mainnet use the latest block number https://etherscan.io/

Run the application

In order to run use the following command

make -j4 && ./artifacts/mosoly-ledger-bridge \
  -service.env "local" \
  -noconsul \
  -db.host "localhost" \
  -db.name "ledger_bridge_cache" \
  -db.user "mosoly" \
  -db.pass "qwerty123456" \
  -db.port "45433" \
  -ethereum.json.rpc.url "https://ropsten.infura.io/" \
  -app.mosoly.ops.account "54068abd52c9592304c068c1101c2a5773b23b79406348403b462a4ea8d40636" \
  -ethereum.passport.factory.address "0x35Cb95Db8E6d56D1CF8D5877EB13e9EE74e457F2" \
  -app.mosoly.did.address "0xD0cC759A5380525CbDeB3C1Dd59de3a21A637176" \
  -app.mosoly.backend.url "http://localhost:9001/api" \
  -app.mosoly.backend.token "ZXlKaGJHY2lPaUpJVXpJMU5pSjkuZXlKemRXSWlPaUpCVUZCVlUwVlNJbjAudG54Zk0xTG5xOE9KTGU3STVLVHFCa0luTzBPQ1FyM0xfbGh4VlIwcmR4bw=="

Lint & build

Sort imports:

goimports -w $(find . -type f -name '*.go' -not -path "./vendor/*")

To lint and build the application with current changes, do make -j4 all. It installs all required Go tools, lints and builds the code. It is also what runs inside CI job container and it's usually faster if you do it first on your machine before pushing.

However, your IDE should probably be also able to tell most of the important problems. Go builds very fast and thus it's possible to see build errors and warnings very quickly while working.

You can modify the arguments the way you see fit for the feature you're developing. Please see config/config.go to find out what each argument helps us with.

Metrics and debug counters

Service exposes metrics and some debug counters via HTTP at /debug/vars in JSON format: http://localhost:8087/debug/vars

Prometheus metrics endpoint: http://localhost:8087/metrics