# Query node

This is a query-node project generated by `hydra-cli`. Experiment by modifying `schema.graphql` and the mappings in the `mappings` folder, defined in `manifest.yml`.

For more information about Hydra see: https://dzhelezov.gitbook.io/hydra/

## 1. Building the node

Run

```bash
# Make sure these steps are executed first:
# yarn build:packages; # OR:
# yarn && yarn workspace @joystream/types build && yarn workspace @joystream/metadata-protobuf build
yarn workspace query-node-root build
```

This will generate event decorations for the mappings via `hydra-typegen` inside `mappings/generated` (based on the runtime metadata saved in `../chain-metadata.json`) and a graphql-server along with the TypeORM models based on `schema.graphql` inside `generated/graphql-server`.

## 2. Building the mappings

In order to re-build the mappings only, without re-generating the graphql-server code and event decorations (in case there were no changes in the runtime and `schema.graphql`) you can also run:

```bash
yarn workspace query-node-mappings build
```

## 3. Initializing the database and starting the node

```bash
yarn workspace query-node-root start
```

This script script will:
- Bring up `joystream-node` service (if not already started)
- Bring up `db` service (query node is using a PostgreSQL database to store the data)
- Configure the database (`yarn workspace query-node config:dev`)
- Create the database and initialize schema (`yarn workspace query-node-root db:prepare && yarn workspace query-node-root db:processor:migrate`)
- Start the GraphQL server service (`docker-compose up -d graphql-server`)
- Start the Hydra Processor responsible for processing the runtime events and running the mappings' functions (`docker-compose up -d processor`)

## 4. Stopping the node and removing all associated containers

You can stop the query-node and remove all associated docker containers without affecting any other services by running:

```bash
yarn workspace query-node-root kill
```