This is a sample project generated by hydra-cli scaffold. Experiment by modifying schema.graphql and the mappings in the mappings folder.

just up
just codegen
just build
just reset
just explore

Start processor

just process

Run GraphQL queries

just serve

• Node v14x
• Docker

# The dependencies setup relies on de-duplication, use `ci` to get everything right
npm ci

# Start a postgres instance
docker-compose up db # add optional -d flag to detach from terminal

# Apply migrations related to the processor's state keeping tables
npm run processor:migrate

# Apply the project's migrations
npm run db:migrate

# Now you can start processing chain data
npm run processor:start

# The above command will block
# Open a separate terminal and launch the graphql server to query the processed data
npm run query-node:start

Hydra tools expect a certain directory layout:

• src/generated - model/server definitions created by codegen. Do not alter the contents of this directory manually.
• src/server-extension - module with custom type-graphql based resolvers
• src/types - data type definitions for chain events and extrinsics created by typegen.
• src/mappings - mapping module.
• lib - compiled js files. The structure of this directory must reflect src.
• .env - hydra tools are heavily driven by environment variables defined here or supplied by a shell.

If you do not plan to extend GraphQl server you can delete server-extension module and then remove type-graphql and class-validator dependencies.

If you modified schema.graphql:

# Run codegen to re-generate model/server files
npm run codegen

# Analyze database state and create a new migration to match generated models
npm run db:create-migration # add -n "myName" to skip the migration name prompt

# Apply the migrations
npm run db:migrate

You might want update the Initial migration instead of creating a new one (e.g. during the development phase when the production database is not yet set up). In that case it convenient to reset the database schema and start afresh:

rm db/migrations/LastUnappliedMigration.ts
npm run db:reset
npm run db:create-migration
npm run db:migrate

To generate new type definitions for chain events and extrinsics:

# Review typegen section of manifest.yml (https://docs.subsquid.io/hydra-typegen)

# Delete old definitions
rm -rf src/types

# Run typegen tool
npm run typegen

In case you just want to extend resolvers you don't index the whole project and just import the postgres database (last data 11.05.2022):

1. Download the data
2. docker-compose up db
3. docker exec -it rubick-db-1 psql -U postgres -d postgres -c "CREATE DATABASE squid;"
4. docker exec -i rubick-db-1 psql -U postgres -d squid < rubick.sql

⚠️ In case the command does not work, check if the container is called rubick-db-1.

For more details, please check out https://docs.subsquid.io.