Jaeger¶

Datakit 内嵌的 Jaeger Agent 用于接收，运算，分析 Jaeger Tracing 协议数据。

Jaeger 文档¶

配置 Jaeger Agent¶

Info

当前 Jaeger 版本支持 HTTP 和 UDP 通信协议和 Apache Thrift 编码规范

主机安装Kubernetes

进入 DataKit 安装目录下的 conf.d/jaeger 目录，复制 jaeger.conf.sample 并命名为 jaeger.conf。示例如下：

[[inputs.jaeger]]
  # Jaeger endpoint for receiving tracing span over HTTP.
  # Default value set as below. DO NOT MODIFY THE ENDPOINT if not necessary.
  endpoint = "/apis/traces"

  # Jaeger agent host:port address for UDP transport.
  # address = "127.0.0.1:6831"

  ## customer_tags is a list of keys contains keys set by client code like span.SetTag(key, value)
  ## that want to send to data center. Those keys set by client code will take precedence over
  ## keys in [inputs.jaeger.tags]. DOT(.) IN KEY WILL BE REPLACED BY DASH(_) WHEN SENDING.
  # customer_tags = ["key1", "key2", ...]

  ## Keep rare tracing resources list switch.
  ## If some resources are rare enough(not presend in 1 hour), those resource will always send
  ## to data center and do not consider samplers and filters.
  # keep_rare_resource = false

  ## Ignore tracing resources map like service:[resources...].
  ## The service name is the full service name in current application.
  ## The resource list is regular expressions uses to block resource names.
  ## If you want to block some resources universally under all services, you can set the
  ## service name as "*". Note: double quotes "" cannot be omitted.
  # [inputs.jaeger.close_resource]
    # service1 = ["resource1", "resource2", ...]
    # service2 = ["resource1", "resource2", ...]
    # "*" = ["close_resource_under_all_services"]
    # ...

  ## Sampler config uses to set global sampling strategy.
  ## sampling_rate used to set global sampling rate.
  # [inputs.jaeger.sampler]
    # sampling_rate = 1.0

  # [inputs.jaeger.tags]
    # key1 = "value1"
    # key2 = "value2"
    # ...

  ## Threads config controls how many goroutines an agent cloud start to handle HTTP request.
  ## buffer is the size of jobs' buffering of worker channel.
  ## threads is the total number fo goroutines at running time.
  ## timeout is the duration(ms) before a job can return a result.
  # [inputs.jaeger.threads]
    # buffer = 100
    # threads = 8

  ## Storage config a local storage space in hard dirver to cache trace data.
  ## path is the local file path used to cache data.
  ## capacity is total space size(MB) used to store data.
  # [inputs.jaeger.storage]
    # path = "./jaeger_storage"
    # capacity = 5120

配置好后，重启 DataKit 即可。

目前可以通过 ConfigMap 方式注入采集器配置来开启采集器。

配置 Jaeger HTTP Agent¶

endpoint 代表 Jaeger HTTP Agent 路由

[[inputs.jaeger]]
  # Jaeger endpoint for receiving tracing span over HTTP.
  # Default value set as below. DO NOT MODIFY THE ENDPOINT if not necessary.
  endpoint = "/apis/traces"

修改 Jaeger Client 的 Agent Host Port 为 Datakit Port（默认为 9529）
修改 Jaeger Client 的 Agent endpoint 为上面配置中指定的 endpoint

配置 Jaeger UDP Agent¶

修改 Jaeger Client 的 Agent UDP Host:Port 为下面配置中指定的 address：

[[inputs.jaeger]]
  # Jaeger agent host:port address for UDP transport.
  address = "127.0.0.1:6831"

有关数据采样，数据过滤，关闭资源等配置请参考Datakit Tracing

Golang 示例¶

以下是一个 HTTP Agent 示例：

package main

import (
  "fmt"
  "io"
  "log"
  "net/http"
  "net/http/httptest"
  "time"

  "github.com/opentracing/opentracing-go"
  "github.com/opentracing/opentracing-go/ext"
  "github.com/uber/jaeger-client-go"
  jaegercfg "github.com/uber/jaeger-client-go/config"
  jaegerlog "github.com/uber/jaeger-client-go/log"
)

var tracer opentracing.Tracer

func main() {
  jgcfg := jaegercfg.Configuration{
    ServiceName: "jaeger_sample_http",
    Sampler: &jaegercfg.SamplerConfig{
      Type:  jaeger.SamplerTypeConst,
      Param: 1,
    },
    Reporter: &jaegercfg.ReporterConfig{
      CollectorEndpoint:   "http://localhost:9529/apis/traces",
      HTTPHeaders:         map[string]string{"Content-Type": "application/x-thrift"},
      BufferFlushInterval: time.Second,
      LogSpans:            true,
    },
  }

  var (
    closer io.Closer
    err    error
  )
  tracer, closer, err = jgcfg.NewTracer(jaegercfg.Logger(jaegerlog.StdLogger))
  defer func() {
    if err := closer.Close(); err != nil {
      log.Println(err.Error())
    }
  }()
  if err != nil {
    log.Panicln(err.Error())
  }

  srv := httptest.NewServer(http.HandlerFunc(func(resp http.ResponseWriter, req *http.Request) {
    spctx, err := tracer.Extract(opentracing.HTTPHeaders, opentracing.HTTPHeadersCarrier(req.Header))
    var span opentracing.Span
    if err != nil {
      log.Println(err.Error())
      span = tracer.StartSpan(req.RequestURI)
    } else {
      span = tracer.StartSpan(req.RequestURI, ext.RPCServerOption(spctx))
    }
    defer span.Finish()

    span.SetTag("finish_ts", time.Now())

    resp.Write([]byte("hello, world"))
  }))

  for i := 0; i < 100; i++ {
    send(srv.URL, i)

    time.Sleep(time.Second)
  }
}

func send(urlstr string, i int) {
  span := tracer.StartSpan(fmt.Sprintf("main_loop->send(%d)", i))
  defer span.Finish()

  req, err := http.NewRequest(http.MethodGet, urlstr, nil)
  if err != nil {
    log.Println(err.Error())

    return
  }

  if err = tracer.Inject(span.Context(), opentracing.HTTPHeaders, opentracing.HTTPHeadersCarrier(req.Header)); err != nil {
    log.Panicln(err.Error())

    return
  }

  span.SetTag(fmt.Sprintf("send_%d_finish", i), time.Now())
}

Golang UDP 示例¶

以下是一个 UDP Agent 示例：

package main

import (
  "io"
  "log"
  "time"

  "github.com/opentracing/opentracing-go"
  "github.com/uber/jaeger-client-go"
  jaegercfg "github.com/uber/jaeger-client-go/config"
  jaegerlog "github.com/uber/jaeger-client-go/log"
)

var tracer opentracing.Tracer

func main() {
  jgcfg := jaegercfg.Configuration{
    ServiceName: "jaeger_sample_app",
    Sampler: &jaegercfg.SamplerConfig{
      Type:  jaeger.SamplerTypeConst,
      Param: 1,
    },
    Reporter: &jaegercfg.ReporterConfig{
      LocalAgentHostPort:  "127.0.0.1:6831",
      BufferFlushInterval: time.Second,
      LogSpans:            true,
    },
  }

  var (
    closer io.Closer
    err    error
  )
  tracer, closer, err = jgcfg.NewTracer(jaegercfg.Logger(jaegerlog.StdLogger))
  defer func() {
    if err := closer.Close(); err != nil {
      log.Println(err.Error())
    }
  }()
  if err != nil {
    log.Panicln(err.Error())
  }

  for i := 0; i < 10; i++ {
    foo()

    time.Sleep(time.Second)
  }
}

func foo() {
  span := tracer.StartSpan("foo")
  defer span.Finish()

  span.SetTag("finish_ts", time.Now())
}

指标集¶

`jaeger`¶

标签

标签名	描述
`container_host`	container hostname
`endpoint`	endpoint info
`env`	application environment info
`http_method`	http request method name
`http_status_code`	http response code
`operation`	span name
`project`	project name
`service`	service name
`source_type`	tracing source type
`span_type`	span type
`status`	span status
`version`	application version info

指标列表

指标	描述	数据类型	单位
`duration`	duration of span	int	μs
`message`	origin content of span	string	-
`parent_id`	parent span ID of current span	string	-
`pid`	application process id.	string	-
`priority`		int	-
`resource`	resource name produce current span	string	-
`span_id`	span id	string	-
`start`	start time of span.	int	usec
`trace_id`	trace id	string	-