support installing with existing volumes and droplets

lib/blockchain/common.js

@@ -12,7 +12,8 @@ module.exports = {
   randomPass,
   fetchAndInstall,
   logger,
-  isInstalledSoftware
+  isInstalledSoftware,
+  writeFile
 }
 
 const BINARIES = {
@@ -70,7 +71,7 @@ stdout_logfile=/var/log/supervisor/${blockchain}.out.log
 environment=HOME="/root"
 `
 
-  fs.writeFileSync(`/etc/supervisor/conf.d/${coinRec.code}.conf`, supervisorConfig)
+  writeFile(`/etc/supervisor/conf.d/${coinRec.code}.conf`, supervisorConfig)
 }
 
 function isInstalledSoftware (coinRec) {
@@ -80,7 +81,7 @@ function isInstalledSoftware (coinRec) {
 function fetchAndInstall (coinRec) {
   if (isInstalledSoftware(coinRec)) return
 
-  const binaries = BINARIES[coinRec.coinRecCode]
+  const binaries = BINARIES[coinRec.cryptoCode]
   if (!binaries) throw new Error(`No such coin: ${coinRec.code}`)
 
   const url = binaries.url
@@ -91,3 +92,15 @@ function fetchAndInstall (coinRec) {
   es(`tar -xzf ${downloadFile}`)
   es(`sudo cp ${binDir}/* /usr/local/bin`)
 }
+
+function writeFile (path, content) {
+  try {
+    fs.writeFileSync(path, content)
+  } catch (err) {
+    if (err.code === 'EEXIST') {
+      logger.info(`${path} exists, skipping.`)
+    }
+
+    throw err
+  }
+}