Move `postgresql_interface.js to lib

lib/postgresql_interface.js

@@ -0,0 +1,69 @@
+'use strict';
+
+var pg = require('pg');
+var PG_ERRORS = {
+  23505: 'uniqueViolation'
+};
+
+var PostgresqlInterface = function (conString) {
+  if (!conString) {
+    throw new Error('Postgres connection string is required');
+  }
+
+  this.client = new pg.Client(conString);
+
+  // TODO better logging
+  this.client.on('error', function (err) { console.log(err); });
+
+  this.client.connect();
+};
+PostgresqlInterface.factory = function factory(conString) { return new PostgresqlInterface(conString); };
+module.exports = PostgresqlInterface;
+
+PostgresqlInterface.prototype.summonTransaction = 
+  function summonTransaction(deviceFingerprint, tx, cb) {
+  // First do an INSERT
+  // If it worked, go ahead with transaction
+  // If duplicate, fetch status and return
+  var self = this;
+  this.client.query('INSERT INTO transactions (id, status, deviceFingerprint, ' +
+      'toAddress, satoshis, currencyCode, fiat) ' + 
+      'VALUES ($1, $2, $3, $4, $5, $6, $7)', [tx.txId, 'pending', deviceFingerprint,
+      tx.toAddress, tx.satoshis, tx.currencyCode, tx.fiat], 
+      function (err) {
+    if (err && PG_ERRORS[err.code] === 'uniqueViolation')
+      return self._fetchTransaction(tx.txId, cb);
+    if (err) return cb(err);
+    cb(null, true);
+  });
+};
+
+PostgresqlInterface.prototype.reportTransactionError = 
+  function reportTransactionError(tx, err) {
+  this.client.query('UPDATE transactions SET status=$1, error=$2 WHERE id=$3', 
+    ['failed', err.message, tx.txId]);
+};
+
+PostgresqlInterface.prototype.completeTransaction = 
+  function completeTransaction(tx, txHash) {
+  if (txHash)
+    this.client.query('UPDATE transactions SET txHash=$1, status=$2, completed=now() WHERE id=$3', 
+      [txHash, 'completed', tx.txId]);
+  else
+    this.client.query('UPDATE transactions SET status=$1, error=$2 WHERE id=$3', 
+      ['failed', 'No txHash received', tx.txId]);    
+};
+
+PostgresqlInterface.prototype._fetchTransaction = 
+    function _fetchTransaction(txId, cb) {
+  this.client.query('SELECT status, txHash FROM transaction WHERE id=$1', 
+      [txId], function (err, rows) {
+    if (err) return cb(err);
+
+    // This should never happen, since we already checked for existence
+    if (rows === 0) return cb(new Error('Couldn\'t find transaction.')); 
+
+    var result = rows[0];
+    cb(null, false, result.txHash);
+  });
+};