Nginx 访问日志
grok
Logstash 默认自带了 apache 标准日志的 grok 正则:
COMMONAPACHELOG %{IPORHOST:clientip} %{USER:ident} %{NOTSPACE:auth} \[%{HTTPDATE:timestamp}\] "(?:%{WORD:verb} %{NOTSPACE:request}(?: HTTP/%{NUMBER:httpversion})?|%{DATA:rawrequest})" %{NUMBER:response} (?:%{NUMBER:bytes}|-)
COMBINEDAPACHELOG %{COMMONAPACHELOG} %{QS:referrer} %{QS:agent}
对于 nginx 标准日志格式，可以发现只是最后多了一个 $http_x_forwarded_for 变量。所以 nginx 标准日志的 grok 正则定义是：
MAINNGINXLOG %{COMBINEDAPACHELOG} %{QS:x_forwarded_for}
自定义的日志格式，可以照此修改。
split
nginx 日志因为部分变量中内含空格，所以很多时候只能使用 %{QS} 正则来做分割，性能和细度都不太好。如果能自定义一个比较少见的字符作为分隔符，那么处理起来就简单多了。假设定义的日志格式如下：
log_format main "$http_x_forwarded_for | $time_local | $request | $status | $body_bytes_sent | "
"$request_body | $content_length | $http_referer | $http_user_agent | $nuid | "
"$http_cookie | $remote_addr | $hostname | $upstream_addr | $upstream_response_time | $request_time";
实际日志如下：
117.136.9.248 | 08/Apr/2015:16:00:01 +0800 | POST /notice/newmessage?sign=cba4f614e05db285850cadc696fcdad0&token=JAGQ92Mjs3--gik_b_DsPIQHcyMKYGpD&did=4b749736ac70f12df700b18cd6d051d5&osn=android&osv=4.0.4&appv=3.0.1&net=460-02-2g&longitude=120.393006&latitude=36.178329&ch=360&lp=1&ver=1&ts=1428479998151&im=869736012353958&sw=0&sh=0&la=zh-CN&lm=weixin&dt=vivoS11t HTTP/1.1 | 200 | 132 | abcd-sign-v1://dd03c57f8cb6fcef919ab5df66f2903f:d51asq5yslwnyz5t/{\x22type\x22:4,\x22uid\x22:7567306} | 89 | - | abcd/3.0.1, Android/4.0.4, vivo S11t | nuid=0C0A0A0A01E02455EA7CF47E02FD072C1428480001.157 | - | 10.10.10.13 | bnx02.abcdprivate.com | 10.10.10.22:9999 | 0.022 | 0.022 59.50.44.53 | 08/Apr/2015:16:00:01 +0800 | POST /feed/pubList?appv=3.0.3&did=89da72550de488328e2aba5d97850e9f&dt=iPhone6%2C2&im=B48C21F3-487E-4071-9742-DC6D61710888&la=cn&latitude=0.000000&lm=weixin&longitude=0.000000&lp=-1.000000&net=0-0-wifi&osn=iOS&osv=8.1.3&sh=568.000000&sw=320.000000&token=7NobA7asg3Jb6n9o4ETdPXyNNiHwMs4J&ts=1428480001275 HTTP/1.1 | 200 | 983 | abcd-sign-v1://b398870a0b25b29aae65cd553addc43d:72214ee85d7cca22/{\x22nextkey\x22:\x22\x22,\x22uid\x22:\x2213062545\x22,\x22token\x22:\x227NobA7asg3Jb6n9o4ETdPXyNNiHwMs4J\x22} | 139 | - | Shopping/3.0.3 (iPhone; iOS 8.1.3; Scale/2.00) | nuid=0C0A0A0A81DF2455017D548502E48E2E1428480001.154 | nuid=CgoKDFUk34GFVH0BLo7kAg== | 10.10.10.11 | bnx02.abcdprivate.com | 10.10.10.35:9999 | 0.025 | 0.026
然后还可以针对 request 做更细致的切分。比如 URL 参数部分。很明显，URL 参数中的字段，顺序是乱的，第一行，问号之后的第一个字段是 sign，第二行问号之后的第一个字段是 appv，所以需要将字段进行切分，取出每个字段对应的值。官方自带 grok 满足不了要求。最终采用的 logstash 配置如下：
filter {
ruby {
init => "@kname = ['http_x_forwarded_for','time_local','request','status','body_bytes_sent','request_body','content_length','http_referer','http_user_agent','nuid','http_cookie','remote_addr','hostname','upstream_addr','upstream_response_time','request_time']"
code => "
new_event = LogStash::Event.new(Hash[@kname.zip(event.get('message').split('|'))])
new_event.remove('@timestamp')
event.append(new_event)
"
}
if [request] {
ruby {
init => "@kname = ['method','uri','verb']"
code => "
new_event = LogStash::Event.new(Hash[@kname.zip(event.get('request').split(' '))])
new_event.remove('@timestamp')
event.append(new_event)
"
}
if [uri] {
ruby {
init => "@kname = ['url_path','url_args']"
code => "
new_event = LogStash::Event.new(Hash[@kname.zip(event.get('uri').split('?'))])
new_event.remove('@timestamp')
event.append(new_event)
"
}
kv {
prefix => "url_"
source => "url_args"
field_split => "& "
remove_field => [ "url_args","uri","request" ]
}
}
}
mutate {
convert => [
"body_bytes_sent" , "integer",
"content_length", "integer",
"upstream_response_time", "float",
"request_time", "float"
]
}
date {
match => [ "time_local", "dd/MMM/yyyy:hh:mm:ss Z" ]
locale => "en"
}
}
最终结果：
{
"message" => "1.43.3.188 | 08/Apr/2015:16:00:01 +0800 | POST /search/suggest?appv=3.0.3&did=dfd5629d705d400795f698055806f01d&dt=iPhone7%2C2&im=AC926907-27AA-4A10-9916-C5DC75F29399&la=cn&latitude=-33.903867&lm=sina&longitude=151.208137&lp=-1.000000&net=0-0-wifi&osn=iOS&osv=8.1.3&sh=667.000000&sw=375.000000&token=_ovaPz6Ue68ybBuhXustPbG-xf1WbsPO&ts=1428480001567 HTTP/1.1 | 200 | 353 | abcd-sign-v1://a24b478486d3bb92ed89a901541b60a5:b23e9d2c14fe6755/{\\x22key\\x22:\\x22last\\x22,\\x22offset\\x22:\\x220\\x22,\\x22token\\x22:\\x22_ovaPz6Ue68ybBuhXustPbG-xf1WbsPO\\x22,\\x22limit\\x22:\\x2220\\x22} | 148 | - | abcdShopping/3.0.3 (iPhone; iOS 8.1.3; Scale/2.00) | nuid=0B0A0A0A9A64AF54F97634640230944E1428480001.113 | nuid=CgoKC1SvZJpkNHb5TpQwAg== | 10.10.10.11 | bnx02.abcdprivate.com | 10.10.10.26:9999 | 0.070 | 0.071",
"@version" => "1",
"@timestamp" => "2015-04-08T08:00:01.000Z",
"type" => "nginxapiaccess",
"host" => "blog05.abcdprivate.com",
"path" => "/home/nginx/logs/api.access.log",
"http_x_forwarded_for" => "1.43.3.188",
"time_local" => " 08/Apr/2015:16:00:01 +0800",
"status" => "200",
"body_bytes_sent" => 353,
"request_body" => "abcd-sign-v1://a24b478486d3bb92ed89a901541b60a5:b23e9d2c14fe6755/{\\x22key\\x22:\\x22last\\x22,\\x22offset\\x22:\\x220\\x22,\\x22token\\x22:\\x22_ovaPz6Ue68ybBuhXustPbG-xf1WbsPO\\x22,\\x22limit\\x22:\\x2220\\x22}",
"content_length" => 148,
"http_referer" => "-",
"http_user_agent" => "abcdShopping/3.0.3 (iPhone; iOS 8.1.3; Scale/2.00)",
"nuid" => "nuid=0B0A0A0A9A64AF54F97634640230944E1428480001.113",
"http_cookie" => "nuid=CgoKC1SvZJpkNHb5TpQwAg==",
"remote_addr" => "10.10.10.11",
"hostname" => "bnx02.abcdprivate.com",
"upstream_addr" => "10.10.10.26:9999",
"upstream_response_time" => 0.070,
"request_time" => 0.071,
"method" => "POST",
"verb" => "HTTP/1.1",
"url_path" => "/search/suggest",
"url_appv" => "3.0.3",
"url_did" => "dfd5629d705d400795f698055806f01d",
"url_dt" => "iPhone7%2C2",
"url_im" => "AC926907-27AA-4A10-9916-C5DC75F29399",
"url_la" => "cn",
"url_latitude" => "-33.903867",
"url_lm" => "sina",
"url_longitude" => "151.208137",
"url_lp" => "-1.000000",
"url_net" => "0-0-wifi",
"url_osn" => "iOS",
"url_osv" => "8.1.3",
"url_sh" => "667.000000",
"url_sw" => "375.000000",
"url_token" => "_ovaPz6Ue68ybBuhXustPbG-xf1WbsPO",
"url_ts" => "1428480001567"
}
如果 url 参数过多，可以不使用 kv 切割，或者预先定义成 nested object 后，改成数组形式：
if [uri] {
ruby {
init => "@kname = ['url_path','url_args']"
code => "
new_event = LogStash::Event.new(Hash[@kname.zip(event.get('request').split('?'))])
new_event.remove('@timestamp')
event.append(new_event)
"
}
if [url_args] {
ruby {
init => "@kname = ['key','value']"
code => "event.set('nested_args', event.get('url_args').split('&').collect {|i| Hash[@kname.zip(i.split('='))]})"
remove_field => [ "url_args","uri","request" ]
}
}
}
采用 nested object 的优化原理和 nested object 的使用方式，请阅读稍后 Elasticsearch 调优章节。
json format
自定义分隔符虽好，但是配置写起来毕竟复杂很多。其实对 logstash 来说，nginx 日志还有另一种更简便的处理方式。就是自定义日志格式时，通过手工拼写，直接输出成 JSON 格式：
log_format json '{"@timestamp":"$time_iso8601",'
'"host":"$server_addr",'
'"clientip":"$remote_addr",'
'"size":$body_bytes_sent,'
'"responsetime":$request_time,'
'"upstreamtime":"$upstream_response_time",'
'"upstreamhost":"$upstream_addr",'
'"http_host":"$host",'
'"url":"$uri",'
'"xff":"$http_x_forwarded_for",'
'"referer":"$http_referer",'
'"agent":"$http_user_agent",'
'"status":"$status"}';
然后采用下面的 logstash 配置即可：
input {
file {
path => "/var/log/nginx/access.log"
codec => json
}
}
filter {
mutate {
split => [ "upstreamtime", "," ]
}
mutate {
convert => [ "upstreamtime", "float" ]
}
}
这里采用多个 mutate 插件，因为 upstreamtime 可能有多个数值，所以先切割成数组以后，再分别转换成浮点型数值。而在 mutate 中，convert 函数执行优先级高于 split 函数，所以只能分开两步写。mutate 内各函数优先级顺序，之前插件介绍章节有详细说明，读者可以返回去加强阅读。
syslog
Nginx 从 1.7 版开始，加入了 syslog 支持。Tengine 则更早。这样我们可以通过 syslog 直接发送日志出来。Nginx 上的配置如下：
access_log syslog:server=unix:/data0/rsyslog/nginx.sock locallog;
或者直接发送给远程 logstash 机器：
access_log syslog:server=192.168.0.2:5140,facility=local6,tag=nginx_access,severity=info logstashlog;
默认情况下，Nginx 将使用 local7.info 等级，nginx 为标签，发送数据。注意，采用 syslog 发送日志的时候，无法配置 buffer=16k 选项。
