feat: creating the coingecko mock API;

crates/shared/src/price_estimation/native/coingecko.rs

@@ -83,7 +83,9 @@ impl CoinGecko {
             Chain::Lens => "lens".to_string(),
             Chain::Linea => "linea".to_string(),
             Chain::Plasma => "plasma".to_string(),
-            Chain::Sepolia | Chain::Goerli | Chain::Hardhat => {
+            // Hardhat/Anvil is a local Ethereum fork, use ethereum pricing for offline development
+            Chain::Hardhat => "ethereum".to_string(),
+            Chain::Sepolia | Chain::Goerli => {
                 anyhow::bail!("unsupported network {}", chain.name())
             }
         };

playground/docker-compose.offline.yml

@@ -31,6 +31,23 @@ services:
       retries: 10
       start_period: 2s
 
+  # Mock Coingecko API for price fetching in offline mode
+  coingecko-mock:
+    build:
+      context: ./mocks/coingecko
+      dockerfile: Dockerfile
+    restart: always
+    environment:
+      - PORT=3000
+    ports:
+      - 3001:3000
+    healthcheck:
+      test: ["CMD-SHELL", "wget -q --spider http://localhost:3000/health || exit 1"]
+      interval: 5s
+      timeout: 3s
+      retries: 5
+      start_period: 5s
+
   db:
     image: postgres:16
     restart: always
@@ -87,15 +104,16 @@ services:
       - NODE_URL=http://chain:8545
       - DB_WRITE_URL=postgres://db:5432/?user=${POSTGRES_USER}&password=${POSTGRES_PASSWORD}
       - DB_READ_URL=postgres://db:5432/?user=${POSTGRES_USER}&password=${POSTGRES_PASSWORD}
-      - LOG_FILTER=orderbook=trace,shared=trace
+      - LOG_FILTER=orderbook=trace,shared=trace,shared::price_estimation=trace,shared::price_estimation::native=trace
       - ACCOUNT_BALANCES_SIMULATION=false
       - ACCOUNT_BALANCES_SIMULATOR=Web3
       - SIMULATION_NODE_URL=http://chain:8545
       - EIP1271_SKIP_CREATION_VALIDATION=true
       - ENABLE_EIP1271_ORDERS=true
       - PRICE_ESTIMATORS=None
       - PRICE_ESTIMATION_DRIVERS=baseline|http://driver/baseline
-      - NATIVE_PRICE_ESTIMATORS=baseline|http://driver/baseline
+      - NATIVE_PRICE_ESTIMATORS=baseline|http://driver/baseline,CoinGecko
+      - COIN_GECKO_URL=http://coingecko-mock:3000/api/v3/simple/token_price
       - DRIVERS=baseline|http://driver/baseline
       - BIND_ADDRESS=0.0.0.0:80
       - BASELINE_SOURCES=UniswapV2
@@ -115,6 +133,8 @@ services:
         condition: service_completed_successfully
       chain:
         condition: service_healthy
+      coingecko-mock:
+        condition: service_healthy
     ports:
       - 8080:80 # API
       - 9586:9586 # metrics
@@ -153,14 +173,14 @@ services:
       - SETTLE_INTERVAL=15s
       - GAS_ESTIMATORS=Native,Web3
       - PRICE_ESTIMATORS=None
-      - NATIVE_PRICE_ESTIMATORS=baseline|http://driver/baseline
+      - NATIVE_PRICE_ESTIMATORS=baseline|http://driver/baseline,CoinGecko
+      - COIN_GECKO_URL=http://coingecko-mock:3000/api/v3/simple/token_price
       - BLOCK_STREAM_POLL_INTERVAL=1s
       - NATIVE_PRICE_CACHE_MAX_UPDATE_SIZE=100
       - NATIVE_PRICE_CACHE_MAX_AGE=20m
       - SOLVER_TIME_LIMIT=5
       - PRICE_ESTIMATION_DRIVERS=baseline|http://driver/baseline
       - RUN_LOOP_NATIVE_PRICE_TIMEOUT=5s
-      - NATIVE_PRICE_ESTIMATORS=baseline|http://driver/baseline
       - NATIVE_PRICE_ESTIMATION_RESULTS_REQUIRED=1
       - DRIVERS=baseline|http://driver/baseline|0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266
       - BASELINE_SOURCES=UniswapV2
@@ -181,6 +201,8 @@ services:
         condition: service_healthy
       chain:
         condition: service_healthy
+      coingecko-mock:
+        condition: service_healthy
     ports:
       - 9589:9589 # metrics
       - 6670:6669 # tokio console

playground/mocks/README.md

@@ -0,0 +1,54 @@
+# Mock Services
+
+This directory contains mock services used for offline development and testing of the CoW Protocol playground.
+
+## Available Mocks
+
+### Coingecko (`./coingecko/`)
+
+Mock implementation of the Coingecko API for price fetching in offline mode.
+
+- **Technology**: Node.js + TypeScript + Hono API
+- **Endpoint**: `/api/v3/simple/token_price/ethereum`
+- **Purpose**: Provides configurable token prices in ETH denomination without requiring external API access
+- **Configuration**: Token prices can be configured in `./coingecko/src/tokens.config.ts`
+
+**Supported Tokens** (offline mode):
+- WETH
+- DAI
+- USDC
+- USDT
+- GNO
+
+See `./coingecko/README.md` for detailed documentation.
+
+## Architecture
+
+Mock services are organized at the playground level to:
+- Maintain clear separation from deployment infrastructure (`offline-mode/`)
+- Improve discoverability of available mocks
+- Enable easy addition of new mock services (e.g., block explorer, subgraph, etc.)
+- Support reusability across different playground configurations
+
+## Adding New Mocks
+
+To add a new mock service:
+
+1. Create a new directory: `mocks/<service-name>/`
+2. Implement the mock service with a Dockerfile
+3. Add the service to `docker-compose.offline.yml`
+4. Update this README with documentation
+
+## Usage
+
+Mock services are automatically started when running the offline playground:
+
+```bash
+docker-compose -f docker-compose.offline.yml up
+```
+
+Individual mocks can be built and run separately:
+
+```bash
+docker-compose -f docker-compose.offline.yml up coingecko-mock
+```

playground/mocks/coingecko/.dockerignore

@@ -0,0 +1,6 @@
+node_modules
+dist
+*.log
+.env
+.DS_Store
+README.md

playground/mocks/coingecko/.gitignore

@@ -0,0 +1,5 @@
+node_modules/
+dist/
+*.log
+.env
+.DS_Store

playground/mocks/coingecko/Dockerfile

@@ -0,0 +1,22 @@
+FROM node:20-alpine
+
+WORKDIR /app
+
+# Copy package files
+COPY package*.json ./
+COPY tsconfig.json ./
+
+# Install dependencies
+RUN npm install
+
+# Copy source code
+COPY src ./src
+
+# Build TypeScript
+RUN npm run build
+
+# Expose port
+EXPOSE 3000
+
+# Start the server
+CMD ["npm", "start"]

playground/mocks/coingecko/README.md

@@ -0,0 +1,118 @@
+# Coingecko Mock API
+
+Mock implementation of the Coingecko API for offline development and testing.
+
+## Overview
+
+This service provides a lightweight mock of the Coingecko API, specifically the `/api/v3/simple/token_price` endpoint. It returns configurable prices for the 5 tokens deployed in offline mode.
+
+## Supported Tokens
+
+The following tokens are supported (configured in `src/tokens.config.ts`):
+
+| Symbol | Address | Price (ETH) |
+|--------|---------|-------------|
+| WETH | `0xb3af08c783c4d9c380893257980b5e26657f2317` | 1.0 |
+| DAI | `0xb12812c0cad46d18b669b31059d485fe90b1a839` | 0.0004 |
+| USDC | `0xb04afbcd351a0a7e4ff658b3772ee5f3f5b6e4ae` | 0.0004 |
+| USDT | `0x171a30524fd943df1a12cbb9da291bf4e34ac84b` | 0.0004 |
+| GNO | `0x51a53858a4a8b81814da35c4604eb9003d56a895` | 0.05 |
+
+## API Endpoints
+
+### Price Fetching
+
+```bash
+GET /api/v3/simple/token_price/ethereum?contract_addresses=<addresses>&vs_currencies=eth&precision=full
+```
+
+**Query Parameters:**
+- `contract_addresses`: Comma-separated list of token contract addresses
+- `vs_currencies`: Currency denomination (only `eth` is supported)
+- `precision`: Precision level (e.g., `full`)
+
+**Example Request:**
+```bash
+curl "http://localhost:3000/api/v3/simple/token_price/ethereum?contract_addresses=0xb3af08c783c4d9c380893257980b5e26657f2317,0xb12812c0cad46d18b669b31059d485fe90b1a839&vs_currencies=eth&precision=full"
+```
+
+**Example Response:**
+```json
+{
+  "0xb3af08c783c4d9c380893257980b5e26657f2317": {
+    "eth": 1.0
+  },
+  "0xb12812c0cad46d18b669b31059d485fe90b1a839": {
+    "eth": 0.0004
+  }
+}
+```
+
+### Health Check
+
+```bash
+GET /health
+```
+
+Returns the service status.
+
+### List Supported Tokens
+
+```bash
+GET /api/v3/tokens
+```
+
+Returns a list of all supported token addresses.
+
+## Local Development
+
+### Prerequisites
+
+- Node.js 20+
+- npm or yarn
+
+### Installation
+
+```bash
+npm install
+```
+
+### Running
+
+```bash
+# Development mode with hot reload
+npm run dev
+
+# Production build
+npm run build
+npm start
+```
+
+### Environment Variables
+
+- `PORT`: Server port (default: 3000)
+
+## Docker
+
+### Build
+
+```bash
+docker build -t coingecko-mock .
+```
+
+### Run
+
+```bash
+docker run -p 3000:3000 coingecko-mock
+```
+
+## Configuration
+
+To add or modify token prices, edit `src/tokens.config.ts` and update the `TOKENS` object.
+
+## Limitations
+
+- Only supports Ethereum platform (`ethereum`)
+- Only supports ETH denomination (`vs_currencies=eth`)
+- Only returns prices for tokens defined in `tokens.config.ts`
+- Does not support historical prices, market caps, or other Coingecko features

playground/mocks/coingecko/package.json

@@ -0,0 +1,23 @@
+{
+  "name": "coingecko-mock",
+  "version": "1.0.0",
+  "description": "Mock Coingecko API for offline development",
+  "main": "dist/index.js",
+  "scripts": {
+    "dev": "tsx watch src/index.ts",
+    "build": "tsc",
+    "start": "node dist/index.js"
+  },
+  "keywords": ["coingecko", "mock", "api"],
+  "author": "",
+  "license": "MIT",
+  "dependencies": {
+    "hono": "^4.0.0",
+    "@hono/node-server": "^1.0.0"
+  },
+  "devDependencies": {
+    "@types/node": "^20.0.0",
+    "tsx": "^4.0.0",
+    "typescript": "^5.0.0"
+  }
+}