Adjust log format to cater for ipv6 values

[m90]

Should fix #1267

The length might seem drastic, but from what I understand a v6 IP might actually grow up to that length:

IPv6 addresses are represented as eight groups of four hexadecimal digits with the groups being separated by colons, for example 2001:0db8:0000:0042:0000:8a2e:0370:7334, but methods to abbreviate this full notation exist.

[codecov]

Codecov Report

Merging #1282 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #1282   +/-   ##
======================================
  Coverage    98.4%   98.4%           
======================================
  Files          34      34           
  Lines        1759    1759           
======================================
  Hits         1731    1731           
  Misses         23      23           
  Partials        5       5

Impacted Files	Coverage Δ
logger.go	100% <100%> (ø)	⬆️

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[appleboy]

check the client ip length first. Please try the following example.

width := 0
if len(clientIP) > 15 {
  width = 39
} else {
  width = 15
}

fmt.Printf("%*s\n", width, "Hello World!")

see https://play.golang.org/p/pLKiETJ-NX

[thinkerou]

width := 15
if len(clientIP) > 15 {
  width = 39
}

[m90]

I have to admit that I already deleted my fork as this was stale for so long.

This is the patch if you want to apply it directly:

diff --git a/logger.go b/logger.go
index c679c78..a93f70e 100644
--- a/logger.go
+++ b/logger.go
@@ -103,10 +103,16 @@ func LoggerWithWriter(out io.Writer, notlogged ...string) HandlerFunc {
                                path = path + "?" + raw
                        }
 
-                       fmt.Fprintf(out, "[GIN] %v |%s %3d %s| %13v | %15s |%s %-7s %s %s\n%s",
+                       width := 15
+                       if len(clientIP) > 15 {
+                               width = 39
+                       }
+
+                       fmt.Fprintf(out, "[GIN] %v |%s %3d %s| %13v | %*s |%s %-7s %s %s\n%s",
                                end.Format("2006/01/02 - 15:04:05"),
                                statusColor, statusCode, resetColor,
                                latency,
+                               width,
                                clientIP,
                                methodColor, method, resetColor,
                                path,

but I could also just create another fork and apply the patch there, but that would need another PR.

[thinkerou]

waiting, @appleboy @m90 @kaustubhmallik maybe we not need width param, because the pull request want to solve misalign, as #1267 picture: one request is ipv4, other request is ipv6, they will not align, so we should use an fixed length not un-fixed according to ipv4 or ipv6.

[theonlypwner]

IPv6 addresses may be up to 45 characters long because of IPv4-mapped IPv6 addresses.

In Linux, INET6_ADDRSTRLEN is 46 for 45 characters plus 1 NULL character.

[appleboy]

move to 1.7 milestones.