feat: backport remote BTC node support

tools/migrate-env.js

@@ -0,0 +1,32 @@
+const fs = require('fs')
+const path = require('path')
+
+const _ = require('lodash/fp')
+const setEnvVariable = require('./set-env-var')
+
+const ENV_PATH = process.env.NODE_ENV === 'production' ? path.resolve('/etc', 'lamassu', '.env') : path.resolve(__dirname, '../.env')
+const BACKUP_TIMESTAMP = Date.now()
+const BACKUP_PATH = `${ENV_PATH}-${BACKUP_TIMESTAMP}`
+
+const migrateEnv = newVars => {
+  try {
+    fs.copyFileSync(ENV_PATH, BACKUP_PATH)
+    _.forEach(it => {
+      setEnvVariable(it[0], it[1], { ENV_PATH })
+    }, newVars)
+    fs.unlinkSync(BACKUP_PATH)
+    console.log('Environment migration successful')
+  } catch (e) {
+    // Rollback the migration and restore the backup file
+    if (fs.existsSync(BACKUP_PATH)) {
+      console.log('Rolling back the environment migration...')
+      fs.copyFileSync(BACKUP_PATH, ENV_PATH)
+      fs.unlinkSync(BACKUP_PATH)
+      console.log('Rollback finished')
+    }
+    console.log('Environment migration failed')
+    throw e
+  }
+}
+
+module.exports = migrateEnv