refactor timestamp reformatting

Author: trigrab

src/gamelog.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-    "errors"
     "log"
     "regexp"
     "strings"
@@ -10,6 +9,11 @@ import (
     "github.com/hpcloud/tail"
 )
 
+// point of time when logging started
+var startTime time.Time
+
+// set this to toggle log reformat of timestamps
+var reformatTimestampsEnabled = true
 
 func tailLog(filename string) ([]string, error) {
 	result := []string{}
@@ -24,57 +28,39 @@ func tailLog(filename string) ([]string, error) {
 		result = append(result, line.Text)
 	}
 
-  result = reformatTimestamps(result)
-
-  return result, nil
-}
-
-
-func getOffset(line string) (string, error) {
-  re, _ := regexp.Compile(`^\d+.\d+`)
-
-  if !re.MatchString(line) {
-    log.Printf("This line has no offset", line)
-    return "error", errors.New(line)
+  if reformatTimestampsEnabled {
+    result = reformatTimestamps(result)
   }
 
-  offset := re.FindString(line)
-
-  return offset, nil
+  return result, nil
 }
 
-
-func getStartTime(line string) (time.Time) {
+func getStartTime(log []string) {
   re, _ := regexp.Compile(`\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}`)
-  date := string(re.FindString(line))
-  startTime, _ := time.Parse(time.RFC3339, strings.Replace(date, " ", "T", 1) + "Z")
-
-  return startTime
+  date := string(re.FindString(log[0]))
+  startTime, _ = time.Parse(time.RFC3339, strings.Replace(date, " ", "T", 1) + "Z")
 }
 
-
-func replaceTimestampInLine(line string, offset string, startTime time.Time) (string) {
-    offset, err := getOffset(line)
-    offsetDuration, _ := time.ParseDuration(offset + "s")
+// convert an offset timestamp from the log to a human readable timestamp
+func offsetToTimestamp(offset string) (string) {
+    offsetDuration, err := time.ParseDuration(offset + "s")
     timestamp := startTime.Add(offsetDuration)
 
     if err == nil  {
-      return timestamp.Format("2006-01-02 15:04:05") +  ":" + strings.Replace(line, offset, "", 1)
+      return timestamp.Format("2006-01-02 15:04:05") +  ":" + strings.Replace(offset, offset, "", 1)
     } else {
-      return line
+      return offset
     }
 }
 
-
 func reformatTimestamps(log []string) ([]string) {
-  firstLine := log[0]
-  startTime := getStartTime(firstLine)
+  getStartTime(log)
   result := []string{}
 
   for i := range log {
     line := strings.TrimLeft(log[i], " \t")
-    offset, _ := getOffset(line)
-    result = append(result, replaceTimestampInLine(line, offset, startTime))
+    re, _ := regexp.Compile(`^\d+\.\d+`)
+    result = append(result, re.ReplaceAllStringFunc(line, offsetToTimestamp))
   }
 
   return result