feat(kafka-logger): support for specified the log formats via admin API.

apisix/plugins/http-logger.lua

@@ -26,15 +26,11 @@ local ngx      = ngx
 local tostring = tostring
 local pairs    = pairs
 local ipairs   = ipairs
-local str_byte = string.byte
 local timer_at = ngx.timer.at
 
 local plugin_name = "http-logger"
 local stale_timer_running = false
 local buffers = {}
-local lru_log_format = core.lrucache.new({
-    ttl = 300, count = 512
-})
 
 local schema = {
     type = "object",
@@ -59,14 +55,7 @@ local schema = {
 local metadata_schema = {
     type = "object",
     properties = {
-        log_format = {
-            type = "object",
-            default = {
-                ["host"] = "$host",
-                ["@timestamp"] = "$time_iso8601",
-                ["client_ip"] = "$remote_addr",
-            },
-        },
+        log_format = log_util.metadata_schema_log_format,
     },
     additionalProperties = false,
 }
@@ -157,24 +146,6 @@ local function send_http_data(conf, log_message)
 end
 
 
-local function gen_log_format(metadata)
-    local log_format = {}
-    if metadata == nil then
-        return log_format
-    end
-
-    for k, var_name in pairs(metadata.value.log_format) do
-        if var_name:byte(1, 1) == str_byte("$") then
-            log_format[k] = {true, var_name:sub(2)}
-        else
-            log_format[k] = {false, var_name}
-        end
-    end
-    core.log.info("log_format: ", core.json.delay_encode(log_format))
-    return log_format
-end
-
-
 -- remove stale objects from the memory after timer expires
 local function remove_stale_objects(premature)
     if premature then
@@ -198,23 +169,10 @@ function _M.log(conf, ctx)
     core.log.info("metadata: ", core.json.delay_encode(metadata))
 
     local entry
-    local log_format = lru_log_format(metadata or "", nil, gen_log_format,
-                                      metadata)
-    if core.table.nkeys(log_format) > 0 then
-        entry = core.table.new(0, core.table.nkeys(log_format))
-        for k, var_attr in pairs(log_format) do
-            if var_attr[1] then
-                entry[k] = ctx.var[var_attr[2]]
-            else
-                entry[k] = var_attr[2]
-            end
-        end
 
-        local matched_route = ctx.matched_route and ctx.matched_route.value
-        if matched_route then
-            entry.service_id = matched_route.service_id
-            entry.route_id = matched_route.id
-        end
+    if metadata and metadata.value.log_format 
+        and core.table.nkeys(metadata.value.log_format) > 0 then
+        entry = log_util.get_custom_format_log(metadata.value.log_format)
     else
         entry = log_util.get_full_log(ngx, conf)
     end

apisix/plugins/kafka-logger.lua

@@ -18,6 +18,8 @@ local core     = require("apisix.core")
 local log_util = require("apisix.utils.log-util")
 local producer = require ("resty.kafka.producer")
 local batch_processor = require("apisix.utils.batch-processor")
+local plugin = require("apisix.plugin")
+
 local math     = math
 local pairs    = pairs
 local type     = type
@@ -63,15 +65,27 @@ local schema = {
     required = {"broker_list", "kafka_topic"}
 }
 
+local metadata_schema = {
+    type = "object",
+    properties = {
+        log_format = log_util.metadata_schema_log_format,
+    },
+    additionalProperties = false,
+}
+
 local _M = {
     version = 0.1,
     priority = 403,
     name = plugin_name,
     schema = schema,
+    metadata_schema = metadata_schema,
 }
 
 
-function _M.check_schema(conf)
+function _M.check_schema(conf, schema_type)
+    if schema_type == core.schema.TYPE_METADATA then
+        return core.schema.check(metadata_schema, conf)
+    end
     return core.schema.check(schema, conf)
 end
 
@@ -152,8 +166,15 @@ function _M.log(conf, ctx)
         -- core.log.info("origin entry: ", entry)
 
     else
-        entry = log_util.get_full_log(ngx, conf)
-        core.log.info("full log entry: ", core.json.delay_encode(entry))
+        local metadata = plugin.plugin_metadata(plugin_name)
+        core.log.info("metadata: ", core.json.delay_encode(metadata))
+        if metadata and metadata.value.log_format 
+            and core.table.nkeys(metadata.value.log_format) > 0 then
+            entry = log_util.get_custom_format_log(metadata.value.log_format)
+        else
+            entry = log_util.get_full_log(ngx, conf)
+            core.log.info("full log entry: ", core.json.delay_encode(entry))
+        end
     end
 
     if not stale_timer_running then

apisix/utils/log-util.lua

@@ -17,10 +17,58 @@
 local core = require("apisix.core")
 local ngx  = ngx
 local pairs = pairs
+local str_byte = string.byte
 local req_get_body_data = ngx.req.get_body_data
 
+local lru_log_format = core.lrucache.new({
+    ttl = 300, count = 512
+})
+
 local _M = {}
+_M.metadata_schema_log_format = {
+    type = "object",
+    default = {
+        ["host"] = "$host",
+        ["@timestamp"] = "$time_iso8601",
+        ["client_ip"] = "$remote_addr",
+    },
+}
+
+
+local function gen_log_format(format)
+    local log_format = {}
+    for k, var_name in pairs(format) do
+        if var_name:byte(1, 1) == str_byte("$") then
+            log_format[k] = {true, var_name:sub(2)}
+        else
+            log_format[k] = {false, var_name}
+        end
+    end
+    core.log.info("log_format: ", core.json.delay_encode(log_format))
+    return log_format
+end
+
+local function get_custom_format_log(format)
+    local ctx = ngx.ctx.api_ctx
 
+    local log_format = lru_log_format(format or "", nil, gen_log_format, format)
+    local entry = core.table.new(0, core.table.nkeys(log_format))
+    for k, var_attr in pairs(log_format) do
+        if var_attr[1] then
+            entry[k] = ctx.var[var_attr[2]]
+        else
+            entry[k] = var_attr[2]
+        end
+    end
+
+    local matched_route = ctx.matched_route and ctx.matched_route.value
+    if matched_route then
+        entry.service_id = matched_route.service_id
+        entry.route_id = matched_route.id
+    end
+    return entry
+end
+_M.get_custom_format_log = get_custom_format_log
 
 local function get_full_log(ngx, conf)
     local ctx = ngx.ctx.api_ctx

docs/zh/latest/plugins/kafka-logger.md

@@ -138,7 +138,7 @@ title: kafka-logger
 1. 为特定路由启用 kafka-logger 插件。
 
 ```shell
-curl http://127.0.0.1:9080/apisix/admin/routes/5 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
+curl http://127.0.0.1:9080/apisix/admin/routes/1 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
 {
     "plugins": {
        "kafka-logger": {
@@ -171,6 +171,33 @@ HTTP/1.1 200 OK
 hello, world
 ```
 
+## 插件元数据设置
+
+| 名称             | 类型    | 必选项 | 默认值        | 有效值  | 描述                                             |
+| ---------------- | ------- | ------ | ------------- | ------- | ------------------------------------------------ |
+| log_format       | object  | 可选   |               |         | 以 Hash 对象方式声明日志格式。对 value 部分，仅支持字符串。如果是以`$`开头，则表明是要获取 [Nginx 内置变量](http://nginx.org/en/docs/varindex.html)。特别的，该设置是全局生效的，意味着指定 log_format 后，将对所有绑定 kafka-logger 的 Route 或 Service 生效。 |
+
+### 设置日志格式示例
+
+```shell
+curl http://127.0.0.1:9080/apisix/admin/plugin_metadata/kafka-logger -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
+{
+    "log_format": {
+        "host": "$host",
+        "@timestamp": "$time_iso8601",
+        "client_ip": "$remote_addr"
+    }
+}'
+```
+
+在日志收集处，将得到类似下面的日志：
+
+```shell
+{"host":"localhost","@timestamp":"2020-09-23T19:05:05-04:00","client_ip":"127.0.0.1","route_id":"1"}
+{"host":"localhost","@timestamp":"2020-09-23T19:05:05-04:00","client_ip":"127.0.0.1","route_id":"1"}
+```
+
+
 ## 禁用插件
 
 当您要禁用`kafka-logger`插件时，这很简单，您可以在插件配置中删除相应的 json 配置，无需重新启动服务，它将立即生效：

t/plugin/kafka-logger.t

@@ -722,3 +722,43 @@ GET /t
 [qr/partition_id: 1/,
 qr/partition_id: 0/,
 qr/partition_id: 2/]
+
+
+
+=== TEST 20: add plugin metadata
+--- config
+    location /t {
+        content_by_lua_block {
+            local t = require("lib.test_admin").test
+            local code, body = t('/apisix/admin/plugin_metadata/kafka-logger',
+                ngx.HTTP_PUT,
+                [[{
+                    "log_format": {
+                        "host": "$host",
+                        "@timestamp": "$time_iso8601",
+                        "client_ip": "$remote_addr"
+                    }
+                }]],
+                [[{
+                    "node": {
+                        "value": {
+                            "log_format": {
+                                "host": "$host",
+                                "@timestamp": "$time_iso8601",
+                                "client_ip": "$remote_addr"
+                            }
+                        }
+                    },
+                    "action": "set"
+                }]]
+                )
+            ngx.status = code
+            ngx.say(body)
+        }
+    }
+--- request
+GET /t
+--- response_body
+passed
+--- no_error_log
+[error]