go k8s operator logf日志格式化处理详解_memcached


文章目录

1. 简介

操作员SDK生成的操作员使用该logr界面进行记录。此日志界面具有多个后端，例如​​zap​​​，SDK默认在生成的代码中使用这些后端。​​logr.Logger​​公开结构化的日志记录方法，这些方法可帮助创建机器可读的日志并向日志记录添加大量信息。

2. 默认的Zap记录器

在搭建新项目时，Operator SDK使用​​zap​​​基于​​logr​​后端的后端。为了帮助配置和使用此记录器，SDK包含一些帮助器功能。

在下面的简单示例中，我们使用来将zap标志​​BindFlags()​​​集添加到操作员的命令行标志中，然后使用来设置控制器运行时记录器​​zap.Options{}​​。

默认情况下，​​zap.Options{}​​​将返回准备用于生产的记录器。它使用​​JSON​​​编码器，从该​​info​​级别开始记录日志。要自定义默认行为，用户可以使用zap标志集并在命令行上指定标志。zap标志集包括以下标志，可用于配置记录器：

  • ​​--zap-devel​​​：开发模式默认值（encoder = consoleEncoder，logLevel = Debug，stackTraceLevel = Warn）生产模式默认值（encoder = jsonEncoder，logLevel =
    Info，stackTraceLevel = Error）
  • ​​--zap-encoder​​：Zap日志编码（“ json”或“ console”）
  • ​​--zap-log-level​​：Zap Level配置日志的详细程度。可以是’debug’，‘info’，'error’或任何大于0的整数值之一，对应于增加详细程度的自定义调试级别”）
  • ​​--zap-stacktrace-level​​​：Zap级别以及在其之上捕获堆栈跟踪的信息（“ info”或“ error”之一）
    有关更详细的标志信息，请查阅控制器运行时​​​godocs​​。

3. 示例

第一种方法

package main

import (
  "sigs.k8s.io/controller-runtime/pkg/log/zap"  
  logf "sigs.k8s.io/controller-runtime/pkg/log"
  "flag"
)

var globalLog = logf.Log.WithName("global")
func main() {
  // Add the zap logger flag set to the CLI. The flag set must
  // be added before calling flag.Parse().
  opts := zap.Options{}
  opts.BindFlags(flag.CommandLine)
  flag.Parse()

  logger := zap.New(zap.UseFlagOptions(&opts))
  logf.SetLogger(logger)

  scopedLog := logf.Log.WithName("scoped")

  globalLog.Info("Printing at INFO level")
  globalLog.V(1).Info("Printing at DEBUG level")
  scopedLog.Info("Printing at INFO level")
  scopedLog.V(1).Info("Printing at DEBUG level")
}
$ go run main.go
INFO[0000] Running the operator locally in namespace default.
{"level":"info","ts":1587741740.407766,"logger":"global","msg":"Printing at INFO level"}
{"level":"info","ts":1587741740.407855,"logger":"scoped","msg":"Printing at INFO level"}

输出将日志级别覆盖为1（调试）

$ go run main.go --zap-log-level=debug
INFO[0000] Running the operator locally in namespace default.
{"level":"info","ts":1587741837.602911,"logger":"global","msg":"Printing at INFO level"}
{"level":"debug","ts":1587741837.602964,"logger":"global","msg":"Printing at DEBUG level"}
{"level":"info","ts":1587741837.6029708,"logger":"scoped","msg":"Printing at INFO level"}
{"level":"debug","ts":1587741837.602973,"logger":"scoped","msg":"Printing at DEBUG level"}

第二种方法

package main
import (
    "github.com/operator-framework/operator-sdk/pkg/log/zap"
    "github.com/spf13/pflag"
    logf "sigs.k8s.io/controller-runtime/pkg/log"
)
var globalLog = logf.Log.WithName("global")
func main() {
    pflag.CommandLine.AddFlagSet(zap.FlagSet())
    pflag.Parse()
    logf.SetLogger(zap.Logger())
    scopedLog := logf.Log.WithName("scoped")
    globalLog.Info("Printing at INFO level")
    globalLog.V(1).Info("Printing at DEBUG level")
    scopedLog.Info("Printing at INFO level")
    scopedLog.V(1).Info("Printing at DEBUG level")
}
$ go run main.go
{"level":"info","ts":1559866292.307987,"logger":"global","msg":"Printing at INFO level"}
{"level":"info","ts":1559866292.308039,"logger":"scoped","msg":"Printing at INFO level"}
Output overriding the log level to 1 (debug)
$ go run main.go --zap-level=1
{"level":"info","ts":1559866310.065048,"logger":"global","msg":"Printing at INFO level"}
{"level":"debug","ts":1559866310.0650969,"logger":"global","msg":"Printing at DEBUG level"}
{"level":"info","ts":1559866310.065119,"logger":"scoped","msg":"Printing at INFO level"}
{"level":"debug","ts":1559866310.065123,"logger":"scoped","msg":"Printing at DEBUG level"}

4. 自定义zap记录器

为了使用自定义的zap记录器，zap可以使用​​controller-runtime​​来将其包装在logr实现中。

以下是说明​​zap-logfmt​​在日志记录中使用的示例。

例
在您的​​​main.go​​​文件中，将main函数的日志替换为当前的实现：
第一种：
…

// Add the zap logger flag set to the CLI. The flag set must
// be added before calling flag.Parse().
  opts := zap.Options{}
  opts.BindFlags(flag.CommandLine)
  flag.Parse()

  logger := zap.New(zap.UseFlagOptions(&opts))
  logf.SetLogger(logger)
...

第二种

...
// Add the zap logger flag set to the CLI. The flag set must
// be added before calling pflag.Parse().
pflag.CommandLine.AddFlagSet(zap.FlagSet())
// Add flags registered by imported packages (e.g. glog and
// controller-runtime)
pflag.CommandLine.AddGoFlagSet(flag.CommandLine)
pflag.Parse()
// Use a zap logr.Logger implementation. If none of the zap
// flags are configured (or if the zap flag set is not being
// used), this defaults to a production zap logger.
// The logger instantiated here can be changed to any logger
// implementing the logr.Logger interface. This logger will
// be propagated through the whole operator, generating
// uniform and structured logs.
logf.SetLogger(zap.Logger())
...

带有：

import(
  ...
  zaplogfmt "github.com/sykesm/zap-logfmt"
  uzap "go.uber.org/zap"
  "go.uber.org/zap/zapcore"
  logf "sigs.k8s.io/controller-runtime/pkg/log"
  "sigs.k8s.io/controller-runtime/pkg/log/zap"
  ...
)
  configLog := uzap.NewProductionEncoderConfig()
  configLog.EncodeTime = func(ts time.Time, encoder zapcore.PrimitiveArrayEncoder) {
    encoder.AppendString(ts.UTC().Format(time.RFC3339Nano))
  }
  logfmtEncoder := zaplogfmt.NewEncoder(configLog)

  // Construct a new logr.logger.
  logger := zap.New(zap.UseDevMode(true), zap.WriteTo(os.Stdout), zap.Encoder(logfmtEncoder))
  logf.SetLogger(logger)

注意：对于此示例，您需要将模块添加"​​github.com/sykesm/zap-logfmt​​​"到项目中。运行​​go get -u github.com/sykesm/zap-logfmt​​​。完整代码：​​main.go​​

package main

import (
        "time"
        "os"
  zaplogfmt "github.com/sykesm/zap-logfmt"
  uzap "go.uber.org/zap"
  "go.uber.org/zap/zapcore"
  logf "sigs.k8s.io/controller-runtime/pkg/log"
  "sigs.k8s.io/controller-runtime/pkg/log/zap"
)

var globalLog = logf.Log.WithName("global")
func main() {
  // Add the zap logger flag set to the CLI. The flag set must
  // be added before calling flag.Parse().
  configLog := uzap.NewProductionEncoderConfig()
  configLog.EncodeTime = func(ts time.Time, encoder zapcore.PrimitiveArrayEncoder) {
    encoder.AppendString(ts.UTC().Format(time.RFC3339Nano))
  }
  logfmtEncoder := zaplogfmt.NewEncoder(configLog)

  // Construct a new logr.logger.
  logger := zap.New(zap.UseDevMode(true), zap.WriteTo(os.Stdout), zap.Encoder(logfmtEncoder))
  logf.SetLogger(logger)
  scopedLog := logf.Log.WithName("scoped")

  globalLog.Info("Printing at INFO level")
  globalLog.V(1).Info("Printing at DEBUG level")
  scopedLog.Info("Printing at INFO level")
  scopedLog.V(1).Info("Printing at DEBUG level")
}

使用自定义zap记录器进行输出

$ go run main.go
ts=2020-04-30T20:35:59.551268Z level=info logger=global msg="Printing at INFO level"
ts=2020-04-30T20:35:59.551314Z level=debug logger=global msg="Printing at DEBUG level"
ts=2020-04-30T20:35:59.551318Z level=info logger=scoped msg="Printing at INFO level"
ts=2020-04-30T20:35:59.55132Z level=debug logger=scoped msg="Printing at DEBUG level"

通过使用​​sigs.k8s.io/controller-runtime/pkg/log​​​，您的记录器将通过传播​​controller-runtime​​。由controller-runtime代码产生的任何日志都将通过您的记录器，因此具有相同的格式和目的地。

在本地运行时设置标志
当在本地运行时​​​make run ENABLE_WEBHOOKS=false​​​，您可以使用​​ARGSvar​​将其他标志（包括zap标志）传递给操作员。例如：

$ make run ARGS="--zap-encoder=console" ENABLE_WEBHOOKS=false

确保按照下图所示确定run目标。ARGSMakefile

# Run against the configured Kubernetes cluster in ~/.kube/config
run: generate fmt vet manifests
  go run ./main.go $(ARGS)

5. 部署到集群时设置标志

将操作员部署到群集时，可以使用文件中​​args​​​操作员container规范中的数组来设置其他标志，​​config/default/manager_auth_proxy_patch.yaml​​例如：

apiVersion: apps/v1
kind: Deployment
metadata:
  name: controller-manager
  namespace: system
spec:
  template:
    spec:
      containers:
      - name: kube-rbac-proxy
        image: gcr.io/kubebuilder/kube-rbac-proxy:v0.5.0
        args:
        - "--secure-listen-address=0.0.0.0:8443"
        - "--upstream=http://127.0.0.1:8080/"
        - "--logtostderr=true"
        - "--v=10"
        ports:
        - containerPort: 8443
          name: https
      - name: manager
        args:
        - "--metrics-addr=127.0.0.1:8080"
        - "--enable-leader-election"
        - "--zap-encoder=console"
        - "--zap-log-level=debug"

6. 创建结构化的日志语句

使用两种方法可以创建结构化日志logr。您可以在每个日志记录中使用​​log.WithValues(keyValues)​​​包括​​keyValues​​​键值对列表的新记录器interface{}。或者，您可以keyValues直接将其包含在log语句中，因为所有logrlog语句都带有一些消息和keyValues。签名​​logr.Error()​​​具有​​error-type​​参数，可以为nil。

来自的示例​​memcached_controller.go​​：

package memcached

import (
  "github.com/go-logr/logr"
)


// MemcachedReconciler reconciles a Memcached object
type MemcachedReconciler struct {
  client.Client
  Log    logr.Logger
  Scheme *runtime.Scheme
}

func (r *MemcachedReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
  log := r.Log.WithValues("memcached", req.NamespacedName)

  // Fetch the Memcached instance
  memcached := &cachev1alpha1.Memcached{}
  err := r.Get(ctx, req.NamespacedName, memcached)
  if err != nil {
    if errors.IsNotFound(err) {
      // Request object not found, could have been deleted after reconcile request.
      // Owned objects are automatically garbage collected. For additional cleanup logic use finalizers.
      // Return and don't requeue
      log.Info("Memcached resource not found. Ignoring since object must be deleted")
      return ctrl.Result{}, nil
    }
    // Error reading the object - requeue the request.
    log.Error(err, "Failed to get Memcached")
    return ctrl.Result{}, err
  }

  // Check if the deployment already exists, if not create a new one
  found := &appsv1.Deployment{}
  err = r.Get(ctx, types.NamespacedName{Name: memcached.Name, Namespace: memcached.Namespace}, found)
  if err != nil && errors.IsNotFound(err) {
    // Define a new deployment
    dep := r.deploymentForMemcached(memcached)
    log.Info("Creating a new Deployment", "Deployment.Namespace", dep.Namespace, "Deployment.Name", dep.Name)
    err = r.Create(ctx, dep)
    if err != nil {
      log.Error(err, "Failed to create new Deployment", "Deployment.Namespace", dep.Namespace, "Deployment.Name", dep.Name)
      return ctrl.Result{}, err
    }
    // Deployment created successfully - return and requeue
    return ctrl.Result{Requeue: true}, nil
  } else if err != nil {
    log.Error(err, "Failed to get Deployment")
    return ctrl.Result{}, err
  }

  ...
}

日志记录如下所示（从log.Error()上方）：

2020-04-27T09:14:15.939-0400  ERROR  controllers.Memcached  Failed to create new Deployment  {"memcached": "default/memcached-sample", "Deployment.Namespace": "default", "Deployment.Name": "memcached-sample"}

7. 非默认日志记录

如果您不想logr用作日志记录工具，则可以logr从操作员的代码（包括中的logr设置代码）中删除特定的语句而不会出现问题main.go，然后添加自己的语句。请注意，删除​​logr​​​安装代码将阻止​​controller-runtime​​日志记录。