Release: develop -> main

.env.example

@@ -8,7 +8,18 @@ CONFIG_CHAIN=mainnet
 RPC_URL_MAINNET=https://eth-mainnet.g.alchemy.com/v2/[API-KEY]
 RPC_URL_POLYGON=https://polygon-mainnet.g.alchemy.com/v2/[API-KEY]
 
-COINGECKO_API_KEY=[API-KEY]
+# CoinGecko Configuration.
+#
+# COINGECKO_BASE_URL: required. The origin the api calls. Recommended is
+# the in-cluster pricing-proxy (https://github.com/DFXswiss/pricing-proxy),
+# which holds the upstream Pro key and serves a 60 s shared cache. Anything
+# CoinGecko-compatible works (pro-api.coingecko.com, api.coingecko.com, …).
+COINGECKO_BASE_URL=http://pricing-proxy:8080/coingecko
+#
+# COINGECKO_API_KEY: optional. If set, attached as `x-cg-pro-api-key` to
+# every request. Leave unset when talking to the pricing-proxy (proxy injects
+# its own key) or to the public host anonymously.
+# COINGECKO_API_KEY=
 
 TELEGRAM_BOT_TOKEN=[API-KEY]
 TELEGRAM_GROUPS_JSON=telegram.groups.json

.github/workflows/ci.yaml

@@ -0,0 +1,31 @@
+name: CI
+
+on:
+    pull_request:
+        branches: [develop, main]
+    push:
+        branches: [develop, main]
+
+jobs:
+    build:
+        name: Build & Lint
+        runs-on: ubuntu-latest
+        steps:
+            - name: Checkout
+              uses: actions/checkout@v4
+
+            - name: Setup Node.js
+              uses: actions/setup-node@v4
+              with:
+                  node-version: '20'
+                  cache: 'yarn'
+
+            - name: Install dependencies
+              run: yarn install --frozen-lockfile
+
+            - name: Build
+              run: yarn build
+
+            - name: Lint
+              run: yarn lint
+              continue-on-error: true

README.md

@@ -20,13 +20,45 @@ CONFIG_CHAIN=mainnet
 RPC_URL_MAINNET=https://eth-mainnet.g.alchemy.com/v2/[API-KEY]
 RPC_URL_POLYGON=https://polygon-mainnet.g.alchemy.com/v2/[API-KEY]
 
-COINGECKO_API_KEY=[API-KEY]
+# See "CoinGecko" section below.
+COINGECKO_BASE_URL=http://pricing-proxy:8080/coingecko
+# COINGECKO_API_KEY=
 
 TELEGRAM_BOT_TOKEN=[API-KEY]
 TELEGRAM_GROUPS_JSON=telegram.groups.json
 TELEGRAM_IMAGES_DIR=./images
 ```
 
+## CoinGecko
+
+The api fetches token prices from a CoinGecko-compatible endpoint.
+Configuration is two env vars:
+
+| Var | Required | Purpose |
+|---|---|---|
+| `COINGECKO_BASE_URL` | yes | Origin the api calls. |
+| `COINGECKO_API_KEY` | no | Attached as the `x-cg-pro-api-key` header on every request when set. |
+
+The recommended deployment is the
+[**pricing-proxy**](https://github.com/DFXswiss/pricing-proxy) — a small
+caching reverse-proxy in front of CoinGecko Pro. It holds the upstream
+key, serves a 60 s shared cache, validates upstream error envelopes, and
+coalesces concurrent identical requests. When you use the proxy:
+
+```env
+COINGECKO_BASE_URL=http://pricing-proxy:8080/coingecko
+# COINGECKO_API_KEY left unset — the proxy injects its own key
+```
+
+Without the proxy, talk to CoinGecko directly:
+
+```env
+COINGECKO_BASE_URL=https://pro-api.coingecko.com
+COINGECKO_API_KEY=CG-xxxxxxxxxxxxxxxxxxxxxxxx
+```
+
+The api refuses to start without `COINGECKO_BASE_URL`.
+
 ## Running the app
 
 ```bash

api.config.ts

@@ -9,14 +9,22 @@ dotenv.config();
 // Verify environment
 if (process.env.RPC_URL_MAINNET === undefined) throw new Error('RPC_URL_MAINNET not available');
 if (process.env.RPC_URL_POLYGON === undefined) throw new Error('RPC_URL_POLYGON not available');
-if (process.env.COINGECKO_API_KEY === undefined) throw new Error('COINGECKO_API_KEY not available');
+// COINGECKO_BASE_URL is the origin the api calls — typically the in-cluster
+// pricing-proxy (https://github.com/DFXswiss/pricing-proxy), but any
+// CoinGecko-compatible host works. COINGECKO_API_KEY is optional and is
+// only attached as `x-cg-pro-api-key` on every request when set (proxy mode
+// leaves it unset because the proxy injects its own key).
+if (!process.env.COINGECKO_BASE_URL) {
+	throw new Error('COINGECKO_BASE_URL is not set');
+}
 
 // Config type
 export type ConfigType = {
 	app: string;
 	indexer: string;
 	indexerFallback: string;
-	coingeckoApiKey: string;
+	coingeckoBaseUrl: string;
+	coingeckoApiKey: string | undefined;
 	chain: Chain;
 	network: {
 		mainnet: string;
@@ -42,7 +50,8 @@ export const CONFIG: ConfigType = {
 	app: process.env.CONFIG_APP_URL || 'https://app.deuro.com',
 	indexer: process.env.CONFIG_INDEXER_URL || 'https://ponder.deuro.com/',
 	indexerFallback: process.env.CONFIG_INDEXER_FALLBACK_URL || 'https://dev.ponder.deuro.com/',
-	coingeckoApiKey: process.env.COINGECKO_API_KEY,
+	coingeckoBaseUrl: process.env.COINGECKO_BASE_URL,
+	coingeckoApiKey: process.env.COINGECKO_API_KEY || undefined,
 	chain: process.env.CONFIG_CHAIN === 'polygon' ? polygon : mainnet, // @dev: default mainnet
 	network: {
 		mainnet: process.env.RPC_URL_MAINNET,
@@ -112,10 +121,19 @@ export const VIEM_CONFIG = createPublicClient({
 });
 
 // COINGECKO CLIENT
+//
+// Calls go to whatever `COINGECKO_BASE_URL` points at. When the optional
+// `COINGECKO_API_KEY` is set, it is attached as the `x-cg-pro-api-key`
+// header — orthogonal to the base URL, never a fallback. The recommended
+// deployment is the in-cluster pricing-proxy
+// (https://github.com/DFXswiss/pricing-proxy), which injects its own key
+// and leaves COINGECKO_API_KEY unset on every consumer.
 export const COINGECKO_CLIENT = (query: string) => {
-	const hasParams = query.includes('?');
-	const uri: string = `https://pro-api.coingecko.com${query}`;
-	return fetch(`${uri}${hasParams ? '&' : '?'}x_cg_pro_api_key=${CONFIG.coingeckoApiKey}`);
+	const headers: Record<string, string> = { accept: 'application/json' };
+	if (CONFIG.coingeckoApiKey) {
+		headers['x-cg-pro-api-key'] = CONFIG.coingeckoApiKey;
+	}
+	return fetch(`${CONFIG.coingeckoBaseUrl}${query}`, { headers });
 };
 
 // Contract addresses for the active chain