Provide Daily Volume in customer's api

lib/customers.js

@@ -19,13 +19,8 @@ function add (customer) {
 function get (phone) {
   const sql = 'select * from customers where phone=$1'
   return db.oneOrNone(sql, [phone])
-  .then(customer => {
-    if (!customer) return
-    return getDailyVolume(customer.id).then(dailyVolume => {
-      const formatted = camelize(customer)
-      return _.set('dailyVolume', dailyVolume, formatted)
-    })
-  })
+  .then(populateDailyVolume)
+  .then(camelize)
 }
 
 /**
@@ -49,6 +44,7 @@ function update (id, data, userToken) {
   .then(addComplianceOverrides(id, updateData, userToken))
   .then(populateOverrideUsernames)
   .then(computeStatus)
+  .then(populateDailyVolume)
   .then(camelize)
 }
 
@@ -57,9 +53,20 @@ function getById (id, userToken) {
   return db.oneOrNone(sql, [id])
   .then(populateOverrideUsernames)
   .then(computeStatus)
+  .then(populateDailyVolume)
   .then(camelize)
 }
 
+/**
+ * Get and calculate customer's daily volume
+ * for both cash_in & cash_out txs
+ *
+ * @name getDailyVolume
+ * @function
+ *
+ * @param {string} id Customer's id
+ * @returns {Bignumber} Customer's daily volume
+ */
 function getDailyVolume (id) {
   return Promise.all([
     db.one(`select coalesce(sum(fiat), 0) as total from cash_in_txs 
@@ -73,6 +80,23 @@ function getDailyVolume (id) {
   })
 }
 
+/**
+ * Populate customer object
+ * with dailyVolume information
+ *
+ * @name populateDailyVolume
+ * @function
+ *
+ * @param {object} customer Customer object
+ * @returns {object} Customer object populated with dailyVolume
+ */
+function populateDailyVolume (customer) {
+  if (!customer) return
+  return getDailyVolume(customer.id).then(dailyVolume => {
+    return _.set('daily_volume', dailyVolume, customer)
+  })
+}
+
 /**
  * Get all available complianceTypes
  * that can be overriden (excluding hard_limit)
@@ -236,6 +260,7 @@ function batch () {
   .then(customers => Promise.all(_.map(customer => {
     return populateOverrideUsernames(customer)
     .then(computeStatus)
+    .then(populateDailyVolume)
     .then(camelize)
   }, customers)))
 }