add config validation

lamassu-schema.json

@@ -117,7 +117,15 @@
       "enabledIf": [
         "cashOutEnabled"
       ],
-      "fieldValidation": [{"code": "required"}]
+      "fieldValidation": [
+        {
+          "code": "required"
+        },
+        {
+          "code": "min",
+          "min": 0
+        }
+      ]
     },
     {
       "code": "lowBalanceMargin",

lib/settings-loader.js

@@ -6,6 +6,11 @@ const argv = require('minimist')(process.argv.slice(2))
 const pify = require('pify')
 
 const db = require('./db')
+const options = require('./options')
+const logger = require('./logger')
+
+const schemaPath = path.resolve(options.lamassuServerPath, 'lamassu-schema.json')
+const schema = require(schemaPath)
 
 let settingsCache
 
@@ -68,6 +73,7 @@ function loadConfig (versionId) {
 
   return db.oneOrNone(sql, [versionId, 'config'])
   .then(row => row ? row.data.config : [])
+  .then(validate)
 }
 
 function loadLatestConfig () {
@@ -81,6 +87,37 @@ function loadLatestConfig () {
 
   return db.oneOrNone(sql, ['config'])
   .then(row => row ? row.data.config : [])
+  .then(validate)
+}
+
+function checkConstraint (entry, constraint) {
+  switch (constraint.code) {
+    case 'min':
+      return entry.fieldValue.value >= constraint.min
+    default:
+      return true
+  }
+}
+
+function validateConstraint (entry, constraint) {
+  const isValid = checkConstraint(entry, constraint)
+  if (!isValid) logger.error(`Validation error: ${entry.fieldLocator.code} [${constraint.code}]`)
+  return isValid
+}
+
+function validateEntry (entry) {
+  const fieldCode = entry.fieldLocator.code
+  const schemaEntry = _.find(_.matchesProperty('code', fieldCode), schema.fields)
+  if (!schemaEntry) throw new Error(`Unsupported field: ${fieldCode}`)
+
+  const validations = schemaEntry.fieldValidation
+  return _.every(constraint => validateConstraint(entry, constraint), validations)
+}
+
+function validate (config) {
+  const isValid = _.every(validateEntry, config)
+  if (!isValid) throw new Error('Invalid config')
+  return config
 }
 
 function loadAccounts () {