feat: Added log format support in syslog plugin.

apisix/plugins/syslog.lua

@@ -19,10 +19,11 @@ local core = require("apisix.core")
 local log_util = require("apisix.utils.log-util")
 local bp_manager_mod = require("apisix.utils.batch-processor-manager")
 local syslog = require("apisix.plugins.syslog.init")
+local plugin = require("apisix.plugin")
 local plugin_name = "syslog"
 local ngx = ngx
 
-local batch_processor_manager = bp_manager_mod.new("http sys logger")
+local batch_processor_manager = bp_manager_mod.new("sys logger")
 local schema = {
     type = "object",
     properties = {
@@ -42,27 +43,44 @@ local schema = {
 
 local schema = batch_processor_manager:wrap_schema(schema)
 
+local metadata_schema = {
+    type = "object",
+    properties = {
+        log_format = log_util.metadata_schema_log_format,
+    },
+}
+
 local _M = {
     version = 0.1,
     priority = 401,
     name = plugin_name,
     schema = schema,
+    metadata_schema = metadata_schema,
     flush_syslog = syslog.flush_syslog,
 }
 
 
-function _M.check_schema(conf)
-    local ok, err = core.schema.check(schema, conf)
-    if not ok then
-        return false, err
+function _M.check_schema(conf, schema_type)
+    if schema_type == core.schema.TYPE_METADATA then
+        return core.schema.check(metadata_schema, conf)
     end
-
-    return true
+    return core.schema.check(schema, conf)
 end
 
 
 function _M.log(conf, ctx)
-    local entry = log_util.get_full_log(ngx, conf)
+    local metadata = plugin.plugin_metadata(plugin_name)
+    core.log.info("metadata: ", core.json.delay_encode(metadata))
+
+    local entry
+
+    if metadata and metadata.value.log_format
+        and core.table.nkeys(metadata.value.log_format) > 0
+    then
+        entry = log_util.get_custom_format_log(ctx, metadata.value.log_format)
+    else
+        entry = log_util.get_full_log(ngx, conf)
+    end
     syslog.push_entry(conf, ctx, entry)
 end
 

docs/en/latest/plugins/syslog.md

@@ -49,6 +49,40 @@ Logs can be set as JSON objects.
 
 This Plugin supports using batch processors to aggregate and process entries (logs/data) in a batch. This avoids the need for frequently submitting the data. The batch processor submits data every `5` seconds or when the data in the queue reaches `1000`. See [Batch Processor](../batch-processor.md#configuration) for more information or setting your custom configuration.
 
+## Metadata
+
+You can also set the format of the logs by configuring the Plugin metadata. The following configurations are available:
+
+| Name       | Type   | Required | Default                                                                       | Description                                                                                                                                                                                                                                             |
+| ---------- | ------ | -------- | ----------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| log_format | object | False    | {"host": "$host", "@timestamp": "$time_iso8601", "client_ip": "$remote_addr"} | Log format declared as key value pairs in JSON format. Values only support strings. [APISIX](../apisix-variable.md) or [Nginx](http://nginx.org/en/docs/varindex.html) variables can be used by prefixing the string with `$`. |
+
+:::info IMPORTANT
+
+Configuring the Plugin metadata is global in scope. This means that it will take effect on all Routes and Services which use the `syslog` Plugin.
+
+:::
+
+The example below shows how you can configure through the Admin API:
+
+```shell
+curl http://127.0.0.1:9080/apisix/admin/plugin_metadata/syslog -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
+{
+    "log_format": {
+        "host": "$host",
+        "@timestamp": "$time_iso8601",
+        "client_ip": "$remote_addr"
+    }
+}'
+```
+
+With this configuration, your logs would be formatted as shown below:
+
+```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"}
+```
+
 ## Enabling the Plugin
 
 The example below shows how you can enable the Plugin for a specific Route:

t/plugin/syslog.t

@@ -324,3 +324,90 @@ qr/sending a batch logs to 127.0.0.1:(\d+)/
 --- grep_error_log_out
 sending a batch logs to 127.0.0.1:5044
 sending a batch logs to 127.0.0.1:5045
+
+
+=== TEST 9: add log format
+--- config
+    location /t {
+        content_by_lua_block {
+            local t = require("lib.test_admin").test
+            local code, body = t('/apisix/admin/plugin_metadata/syslog',
+                 ngx.HTTP_PUT,
+                 [[{
+                    "log_format": {
+                        "host": "$host",
+                        "client_ip": "$remote_addr"
+                    }
+                }]]
+                )
+            if code >= 300 then
+                ngx.status = code
+            end
+            ngx.say(body)
+        }
+    }
+--- request
+GET /t
+--- response_body
+passed
+
+
+
+=== TEST 10: Add route and Enable Syslog Plugin, batch_max_size=1
+--- config
+    location /t {
+        content_by_lua_block {
+            local t = require("lib.test_admin").test
+            local code, body = t('/apisix/admin/routes/1',
+                 ngx.HTTP_PUT,
+                 [[{
+                        "plugins": {
+                            "syslog": {
+                                "batch_max_size": 1,
+                                "disable": false,
+                                "flush_limit": 1,
+                                "host" : "127.0.0.1",
+                                "port" : 5050
+                            }
+                        },
+                        "upstream": {
+                            "nodes": {
+                                "127.0.0.1:1980": 1
+                            },
+                            "type": "roundrobin"
+                        },
+                        "uri": "/hello"
+                }]]
+                )
+            if code >= 300 then
+                ngx.status = code
+            end
+            ngx.say(body)
+        }
+    }
+--- request
+GET /t
+--- response_body
+passed
+
+
+
+=== TEST 11: hit route and report sys logger
+--- extra_init_by_lua
+    local syslog = require("apisix.plugins.syslog.init")
+    local json = require("apisix.core.json")
+    local log = require("apisix.core.log")
+    local old_f = syslog.push_entry
+    syslog.push_entry = function(conf, ctx, entry)
+        log.info("syslog-log-format => " ..  json.encode(entry))
+        return old_f(conf, ctx, entry)
+    end
+--- request
+GET /hello
+--- response_body
+hello world
+--- wait: 0.5
+--- no_error_log
+[error]
+--- error_log eval
+qr/syslog-log-format.*\{.*"host":"localhost"/