> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dokrypt.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Services

> Configure IPFS, block explorers, indexers, oracles, and custom services.

## Overview

Services are additional infrastructure that runs alongside your blockchain nodes. They're defined under `services:` in `dokrypt.yaml` and started automatically with `dokrypt up`.

## Supported Service Types

| Type             | Description                  | Default Port               |
| ---------------- | ---------------------------- | -------------------------- |
| `ipfs`           | IPFS decentralized storage   | 5001 (API), 8080 (gateway) |
| `blockscout`     | Full-featured block explorer | 4000                       |
| `otterscan`      | Lightweight block explorer   | 5100                       |
| `subgraph`       | The Graph indexing protocol  | 8000                       |
| `ponder`         | Ponder indexing framework    | 42069                      |
| `chainlink-mock` | Mock Chainlink oracle        | —                          |
| `pyth-mock`      | Mock Pyth oracle             | —                          |
| `grafana`        | Monitoring dashboards        | 3000                       |
| `prometheus`     | Metrics collection           | 9090                       |
| `faucet`         | Test token faucet            | 8082                       |
| `mock-bridge`    | Cross-chain bridge simulator | —                          |
| `custom`         | Any Docker image             | —                          |

## IPFS

```yaml theme={null}
services:
  ipfs:
    type: ipfs
    port: 5001          # API port
    gateway_port: 8080  # Gateway port
```

Access the IPFS API at `http://localhost:5001` and the gateway at `http://localhost:8080`.

Upload files via the API:

```bash theme={null}
curl -X POST -F file=@myfile.json http://localhost:5001/api/v0/add
```

## Block Explorers

### Blockscout

Full-featured block explorer with transaction tracing, token tracking, and API.

```yaml theme={null}
services:
  explorer:
    type: blockscout
    chain: ethereum       # Which chain to index
    port: 4000
    depends_on: [ethereum]
```

Browse at `http://localhost:4000`.

### Otterscan

Lightweight, fast block explorer.

```yaml theme={null}
services:
  explorer:
    type: otterscan
    chain: ethereum
    port: 5100
```

## Indexers

### The Graph (Subgraph)

Run a local Graph Node for indexing blockchain data with subgraphs.

```yaml theme={null}
services:
  indexer:
    type: subgraph
    chain: ethereum
```

### Ponder

Modern indexing framework.

```yaml theme={null}
services:
  indexer:
    type: ponder
    chain: ethereum
```

## Oracles

### Chainlink Mock

Simulated Chainlink price feeds with configurable prices and volatility.

```yaml theme={null}
services:
  oracle:
    type: chainlink-mock
    chain: ethereum
    depends_on: [ethereum]
    features:
      feeds:
        - pair: ETH/USD
          price: 2000.00
          decimals: 8
          update_interval: 60s
          volatility:
            enabled: true
            max_deviation_pct: 2.0
        - pair: BTC/USD
          price: 45000.00
          decimals: 8
```

| Feed Config                    | Type       | Description                              |
| ------------------------------ | ---------- | ---------------------------------------- |
| `pair`                         | `string`   | Price pair (e.g., `ETH/USD`)             |
| `price`                        | `float`    | Initial price                            |
| `decimals`                     | `int`      | Price decimals (usually 8 for Chainlink) |
| `update_interval`              | `duration` | How often price updates                  |
| `volatility.enabled`           | `bool`     | Enable random price movements            |
| `volatility.max_deviation_pct` | `float`    | Max % change per update                  |

### Pyth Mock

Simulated Pyth oracle feeds.

```yaml theme={null}
services:
  oracle:
    type: pyth-mock
    chain: ethereum
```

## Monitoring

### Grafana

Pre-configured dashboards for chain metrics.

```yaml theme={null}
services:
  grafana:
    type: grafana
    port: 3000
```

Access at `http://localhost:3000` (default credentials: admin/admin).

### Prometheus

Metrics collection for chain and service monitoring.

```yaml theme={null}
services:
  prometheus:
    type: prometheus
    port: 9090
```

## Faucet

Web-based test token faucet.

```yaml theme={null}
services:
  faucet:
    type: faucet
    chain: ethereum
    port: 8082
```

## Mock Bridge

Cross-chain bridge simulator for multi-chain setups.

```yaml theme={null}
services:
  bridge:
    type: mock-bridge
    chains: [ethereum, polygon]
    confirmation_blocks: 12
    relay_delay: 30s
```

See [Bridge](/features/bridge) for usage details.

## Custom Services

Run any Docker image as a service:

```yaml theme={null}
services:
  my-api:
    type: custom
    image: my-api:latest
    command: ["--port", "3000"]
    ports:
      http: 3000
      ws: 3001
    volumes:
      - "./data:/app/data"
    environment:
      DATABASE_URL: "postgres://localhost/mydb"
      NODE_ENV: "development"
    depends_on: [ethereum]
    healthcheck:
      http: "http://localhost:3000/health"
      interval: 10s
      timeout: 5s
      retries: 3
```

### Custom Build

Build from a local Dockerfile:

```yaml theme={null}
services:
  my-service:
    type: custom
    build:
      context: ./my-service
      dockerfile: Dockerfile
    ports:
      http: 8080
```

## Dependencies

Use `depends_on` to control startup order:

```yaml theme={null}
services:
  explorer:
    type: blockscout
    depends_on: [ethereum]      # Waits for ethereum chain
  indexer:
    type: subgraph
    depends_on: [ethereum, ipfs] # Waits for both
```

Dokrypt resolves dependencies using topological sort (Kahn's algorithm) and starts independent services in parallel.

## Health Checks

Services support health checks to verify they're ready:

```yaml theme={null}
services:
  my-service:
    healthcheck:
      http: "http://localhost:3000/health"  # HTTP endpoint
      # OR
      tcp: "localhost:3000"                  # TCP port check
      interval: 10s                          # Check interval
      timeout: 5s                            # Timeout per check
      retries: 3                             # Retries before unhealthy
```