add logger back

yyx990803 · yyx990803 · commit 6b6d4be4fb2b · 2016-07-04T15:25:02.000-04:00
diff --git a/src/plugins/logger.js b/src/plugins/logger.js
@@ -0,0 +1,52 @@
+// Credits: borrowed code from fcomb/redux-logger
+
+export default function createLogger ({
+  collapsed = true,
+  transformer = state => state,
+  mutationTransformer = mut => mut
+} = {}) {
+  return store => {
+    let prevState = JSON.parse(JSON.stringify(store.state))
+
+    store.subscribe((mutation, state) => {
+      if (typeof console === 'undefined') {
+        return
+      }
+      const nextState = JSON.parse(JSON.stringify(state))
+      const time = new Date()
+      const formattedTime = ` @ ${pad(time.getHours(), 2)}:${pad(time.getMinutes(), 2)}:${pad(time.getSeconds(), 2)}.${pad(time.getMilliseconds(), 3)}`
+      const formattedMutation = mutationTransformer(mutation)
+      const message = `mutation ${mutation.type}${formattedTime}`
+      const startMessage = collapsed
+        ? console.groupCollapsed
+        : console.group
+
+      // render
+      try {
+        startMessage.call(console, message)
+      } catch (e) {
+        console.log(message)
+      }
+
+      console.log('%c prev state', 'color: #9E9E9E; font-weight: bold', prevState)
+      console.log('%c mutation', 'color: #03A9F4; font-weight: bold', formattedMutation)
+      console.log('%c next state', 'color: #4CAF50; font-weight: bold', nextState)
+
+      try {
+        console.groupEnd()
+      } catch (e) {
+        console.log('—— log end ——')
+      }
+
+      prevState = nextState
+    })
+  }
+}
+
+function repeat (str, times) {
+  return (new Array(times + 1)).join(str)
+}
+
+function pad (num, maxLength) {
+  return repeat('0', maxLength - num.toString().length) + num
+}
