merge of features from hosted branch (#7)

major merge of features from the hosted branch that was created temporarily during the initial launch of jambonz.org

lib/routes/error.js

@@ -0,0 +1,24 @@
+const {DbErrorBadRequest, DbErrorUnprocessableRequest, DbErrorForbidden} = require('../utils/errors');
+
+function sysError(logger, res, err) {
+  if (err instanceof DbErrorBadRequest) {
+    logger.info(err, 'invalid client request');
+    return res.status(400).json({msg: err.message});
+  }
+  if (err instanceof DbErrorUnprocessableRequest) {
+    logger.info(err, 'unprocessable request');
+    return res.status(422).json({msg: err.message});
+  }
+  if (err instanceof DbErrorForbidden) {
+    logger.info(err, 'forbidden');
+    return res.status(403).json({msg: err.message});
+  }
+  if (err.code === 'ER_DUP_ENTRY') {
+    logger.info(err, 'duplicate entry on insert');
+    return res.status(422).json({msg: err.message});
+  }
+  logger.error(err, 'Database error');
+  res.status(500).json({msg: err.message});
+}
+
+module.exports = sysError;