Logstash动态模板映射收集Nginx的Json格式日志

Logstash传输给ES的数据会自动映射为5索引，5备份，字段都为text的的索引。这样基本上无法进行数据分析。
所以必须将Logstash的数据按照既定的格式存储在ES中，这时候就要使用到ES模板技术了。在ES中可以定义自定义模板和动态模板，之后es会自动将相关索引映射为模板规定的格式

编译动态映射模板文件bigdata.template：

在Json日志文件中的KEY的位置不固定、或字段数不明确时使用动态映射模板

{
        "template": "bigdata-template",
        "settings": {
                "index.number_of_shards": 5,
                "number_of_replicas": 1
        },
        "mappings": {
                "_default_": {
                        "_all": {
                                "enabled": true,
                                "omit_norms": true
                        },
                        "dynamic_templates": [{
                                "message_field": {
                                        "match": "message",
                                        "match_mapping_type": "string",
                                        "mapping": {
                                                "type": "string",
                                                "index": "analyzed",
                                                "omit_norms": true,
                                                "fielddata": {
                                                        "format": "disabled"
                                                }
                                        }
                                }
                        }, {
                                "string_fields": {
                                        "match": "*",
                                        "match_mapping_type": "string",
                                        "mapping": {
                                                "type": "string",
                                                "index": "not_analyzed",
                                                "doc_values": true
                                        }
                                }
                        }],
                        "properties": {
                                "@timestamp": {
                                        "type": "date"
                                },
                                "@version": {
                                        "type": "string",
                                        "index": "not_analyzed"
                                }
                        }
                }
        }
}

dynamic_templates  就是配置具体的动态模板匹配项
"match_mapping_type": "string" 是匹配固定的类型
"match": "time"    匹配字段名为time的数据
"unmatch": "data" 不匹配字段名为data的数据
mapping 就是将匹配的数据项映射为定义的数据类型

Logstash配置文件 nginx.conf：

input {
    file {
      path => "/usr/local/openresty/nginx/logs/user2.log"
      type => "nginx-bigdata"
      codec => "json"
    }
}

filter {
    json {
      source => "u_data"
    }
}

output {
    if [type] == "nginx-bigdata" {
      elasticsearch {
        hosts => ["172.17.213.60:9200", "172.17.213.61:9200"]
        index => "nginx-bigdata"
        manage_template => false
        template_overwrite => true
        template_name => "bigdata-template"
        template => "/usr/local/logstash-6.2.4/bigdata.template"
        document_type => "nginx-bigdata"
      }
    }
}

Nginx的配置文件中关于JSON日志格式转换的配置：(此处我只保留了需要的一个字段范围)

escape=json  :nginx 1.11.8版本后才提供此参数

 log_format userlog escape=json '{"u_data":"$u_data","@timestamp":"$time_iso8601"}';
 ...
 access_log logs/user.log userlog;

产生的日志格式：

{"u_data":"{"appid":"nchaopai","args":{"contentId":0,"duration":111811,"parentId":0,"totaltime":0,"type":0},"bk":"-","cp_ver":"3.0.5","duid":"2cba98f8ddc18464","e":"nchaopai.main.stay-duration","os":"A","ts":1572584611,"ver":"8.11.11"}"}

 之后在Kibana里看到就是这样的：

常用格式如下：

    log_format log_json escape=json '{"timestamp": "$time_local",'
        '"remote_addr": "$remote_addr",'
        '"referer": "$http_referer",'
        '"request": "$request",'
        '"statu": "$status",'
        '"byte": "$body_bytes_sent",'
        '"agen": "$http_user_agent",'
        '"x_forwarded": "$http_x_forwarded_for",'
        '"up_resp_time": "$upstream_response_time",'
        '"request_time": "$request_time"}';

参考资料：https://doc.yonyoucloud.com/doc/logstash-best-practice-cn/filter/json.html