Load backend secrets from Vault

Dockerfile

@@ -5,7 +5,6 @@ RUN npm ci
 
 FROM node:22-alpine AS build
 WORKDIR /app
-ENV DATABASE_URL="postgresql://mapflow:mapflow@localhost:5432/mapflow"
 COPY --from=deps /app/node_modules ./node_modules
 COPY . .
 RUN npm run prisma:generate

src/config.ts

@@ -1,5 +1,9 @@
 import 'dotenv/config';
 
+import { loadVaultEnvironment } from './vault/env.js';
+
+await loadVaultEnvironment();
+
 export const config = {
   host: process.env.HOST ?? '0.0.0.0',
   port: Number(process.env.PORT ?? '4000'),

src/vault/env.ts

@@ -0,0 +1,65 @@
+type VaultConfig = {
+  address: string;
+  token: string;
+  mount: string;
+  sharedPath: string;
+  projectPath: string;
+};
+
+function requireEnv(name: string) {
+  const value = process.env[name];
+  if (!value) {
+    throw new Error(`${name} is required when VAULT_ENABLED=true.`);
+  }
+  return value;
+}
+
+function vaultConfig(): VaultConfig {
+  return {
+    address: requireEnv('VAULT_ADDR').replace(/\/$/, ''),
+    token: requireEnv('VAULT_TOKEN'),
+    mount: requireEnv('VAULT_KV_MOUNT'),
+    sharedPath: requireEnv('VAULT_SHARED_PATH'),
+    projectPath: requireEnv('VAULT_PROJECT_PATH'),
+  };
+}
+
+async function readVaultPath(config: VaultConfig, path: string) {
+  const response = await fetch(
+    `${config.address}/v1/${config.mount}/data/${path}`,
+    { headers: { 'X-Vault-Token': config.token } },
+  );
+
+  if (!response.ok) {
+    throw new Error(`Vault read failed for ${path}: ${response.status}.`);
+  }
+
+  const payload = (await response.json()) as {
+    data?: { data?: Record<string, unknown> };
+  };
+  const data = payload.data?.data;
+  if (!data) {
+    throw new Error(`Vault path ${path} has no KV v2 data.`);
+  }
+
+  return data;
+}
+
+function applyEnvironment(values: Record<string, unknown>) {
+  for (const [key, value] of Object.entries(values)) {
+    if (typeof value !== 'string') {
+      throw new Error(`Vault value ${key} must be a string.`);
+    }
+    process.env[key] = value;
+  }
+}
+
+export async function loadVaultEnvironment() {
+  if (process.env.VAULT_ENABLED !== 'true') {
+    return;
+  }
+
+  const config = vaultConfig();
+  applyEnvironment(await readVaultPath(config, config.sharedPath));
+  applyEnvironment(await readVaultPath(config, config.projectPath));
+}