一. HTTP Status

1xx

• ngx.HTTP_CONTINUE (100) (first added in the v0.9.20 release)
• ngx.HTTP_SWITCHING_PROTOCOLS (101) (first added in the v0.9.20 release)
   

2xx

• ngx.HTTP_OK (200)
• ngx.HTTP_CREATED (201)
• ngx.HTTP_ACCEPTED (202) (first added in the v0.9.20 release)
• ngx.HTTP_NO_CONTENT (204) (first added in the v0.9.20 release)
• ngx.HTTP_PARTIAL_CONTENT (206) (first added in the v0.9.20 release)
   

3xx

• ngx.HTTP_SPECIAL_RESPONSE (300)
• ngx.HTTP_MOVED_PERMANENTLY (301)
• ngx.HTTP_MOVED_TEMPORARILY (302)
• ngx.HTTP_SEE_OTHER (303)
• ngx.HTTP_NOT_MODIFIED (304)
• ngx.HTTP_TEMPORARY_REDIRECT (307) (first added in the v0.9.20 release)
   

4xx

• ngx.HTTP_BAD_REQUEST (400)
• ngx.HTTP_UNAUTHORIZED (401)
• ngx.HTTP_PAYMENT_REQUIRED (402) (first added in the v0.9.20 release)
• ngx.HTTP_FORBIDDEN (403)
• ngx.HTTP_NOT_FOUND (404)
• ngx.HTTP_NOT_ALLOWED (405)
• ngx.HTTP_NOT_ACCEPTABLE (406) (first added in the v0.9.20 release)
• ngx.HTTP_REQUEST_TIMEOUT (408) (first added in the v0.9.20 release)
• ngx.HTTP_CONFLICT (409) (first added in the v0.9.20 release)
• ngx.HTTP_GONE (410)
• ngx.HTTP_UPGRADE_REQUIRED (426) (first added in the v0.9.20 release)
• ngx.HTTP_TOO_MANY_REQUESTS (429) (first added in the v0.9.20 release)
• ngx.HTTP_CLOSE (444) (first added in the v0.9.20 release)
• ngx.HTTP_ILLEGAL (451) (first added in the v0.9.20 release)
   

5xx

• ngx.HTTP_INTERNAL_SERVER_ERROR (500)
• ngx.HTTP_METHOD_NOT_IMPLEMENTED (501)
• ngx.HTTP_BAD_GATEWAY (502) (first added in the v0.9.20 release)
• ngx.HTTP_SERVICE_UNAVAILABLE (503)
• ngx.HTTP_GATEWAY_TIMEOUT (504) (first added in the v0.3.1rc38 release)
• ngx.HTTP_VERSION_NOT_SUPPORTED (505) (first added in the v0.9.20 release)
• ngx.HTTP_INSUFFICIENT_STORAGE (507) (first added in the v0.9.20 release)
   

二. Log Level

• ngx.STDERR -- 标准输出
• ngx.EMERG -- 紧急报错
• ngx.ALERT -- 报警
• ngx.CRIT -- 严重，系统故障，触发运维告警系统
• ngx.ERR -- 错误，业务不可恢复性错误
• ngx.WARN -- 告警，业务中可忽略错误
• ngx.NOTICE -- 提醒，业务比较重要信息
• ngx.INFO -- 信息，业务琐碎日志信息，包含不同情况判断等
• ngx.DEBUG -- 调试