feat: load connection string from env var (#8142)

When the `NETLIFY_DB_URL` environment variable is present, the `db
connect` command will use that as the connection string instead of the
database.

This makes it possible for agent runners to connect to the database of
the corresponding deploy preview.

Author: eduardoboucas

src/commands/database/connect.ts

@@ -11,6 +11,17 @@ export interface ConnectOptions {
   json?: boolean
 }
 
+function redactConnectionString(connectionString: string): string {
+  try {
+    const url = new URL(connectionString)
+    url.username = ''
+    url.password = ''
+    return url.toString()
+  } catch {
+    return 'database'
+  }
+}
+
 export const connect = async (options: ConnectOptions, command: BaseCommand): Promise<void> => {
   const buildDir = command.netlify.site.root ?? command.project.root ?? command.project.baseDirectory
   if (!buildDir) {
@@ -26,7 +37,7 @@ export const connect = async (options: ConnectOptions, command: BaseCommand): Pr
     return
   }
 
-  log(`Connected to ${connectionString}`)
+  log(`Connected to ${redactConnectionString(connectionString)}`)
 
   // --query: one-shot mode
   if (options.query) {

src/commands/database/db-connection.ts

@@ -25,6 +25,17 @@ interface RawDBConnection {
 }
 
 export async function connectRawClient(buildDir: string): Promise<RawDBConnection> {
+  const envConnectionString = process.env.NETLIFY_DB_URL
+  if (envConnectionString) {
+    const client = new Client({ connectionString: envConnectionString })
+    await client.connect()
+    return {
+      client,
+      connectionString: envConnectionString,
+      cleanup: () => client.end(),
+    }
+  }
+
   const state = new LocalState(buildDir)
   const storedConnectionString = state.get('dbConnectionString')