如何在 Cloud Run 上使用 Stackdriver 日志记录

Question

我正在尝试让 stackdriver 日志记录在 Google Cloud Run（完全托管）中运行的简单 Go 应用程序正常工作，但在 CloudRun 日志中看不到 stackdriver 条目。我根据“官方”stackdriver golang 示例创建了最简单的演示应用程序Cloud Run 文档指出不应执行任何其他操作来写入 stackdriver 日志我的服务使用默认服务帐户我正在使用 Go 1.13 编译代码（Dockerfile 是从Cloud Run 示例“按原样”复制的）我尝试过将其部署到不同的地区，但没有成功使用服务帐户凭据在本地运行容器时，stackdriver 日志消息不会出现在本地终端或 stackdriver 控制台中无论如何，在应用程序启动时，我只看到"Before stackdriver logging"后面的内容，"After stackdriver logging"中间没有其他消息\错误以下是日志记录代码的一部分（使用上面的链接获取完整源代码、Dockerfile 以及构建和运行应用程序的说明）：import (    "context"    "log"    "os"    ...    "cloud.google.com/go/compute/metadata"    "cloud.google.com/go/logging")func main() {    loggingClient, err := stackdriverClient()    ...    log.Println("Before stackdriver logging")    logger.StandardLogger(logging.Info).Println("Stackdriver log")    if err = logger.Flush(); err != nil {        log.Fatalf("Failed to flush client: %v", err)    }    if err = loggingClient.Close(); err != nil {        log.Fatalf("Failed to close client: %v", err)    }    log.Println("After stackdriver logging")    ...}func stackdriverClient() (client *logging.Client, err error) {    var projectID string    if projectID, err = metadata.ProjectID(); err == nil {        client, err = logging.NewClient(context.Background(), projectID)    }    return}

Answer 1

事实证明，日志条目已成功写入
，但logviewer Web UI中的默认 Cloud Run 过滤器不包含它们
下面的过滤器表达式可帮助我获取所有日志：

resource.type = "project" OR resource.type = "cloud_run_revision"

（服务名称、地点、严重程度省略）

“stdout\stderr”日志条目匹配resource.type="cloud_run_revision"，而 stackdriver 日志条目匹配resource.type="project"

Answer 2

由于 Cloud Run 已与 Cloud Logging 集成，因此无需使用 Go 客户端库。我们在 Cloud Run 上运行所有 gRPC 服务，并使用以下内容来确保 Cloud Logging 中的日志格式正确：

package main

import (

    "github.com/rs/zerolog"

    "github.com/rs/zerolog/log"

    "os"

)

// initializeLogging sets up the logging configuration for the service.

// Invoke this method in your Init() method.

func initializeLogging() {

    // Set logging options for production development

    if os.Getenv("ENV") != "DEV" {

        // change the level field name to ensure these are parsed correctly in Stackdriver

        zerolog.LevelFieldName = "severity"

        // UNIX Time is faster and smaller than most timestamps

        zerolog.TimeFieldFormat = zerolog.TimeFormatUnix

    } else {

        // Set logging options for local development

        log.Logger = log.Output(zerolog.ConsoleWriter{Out: os.Stderr})

        zerolog.SetGlobalLevel(zerolog.DebugLevel)

    }

    

    // Example log

    log.Info().Msg("This is how you log at Info level")

}

然后日志会很好地显示以供本地开发。

如果您不想使用任何第三方日志记录库，一个简单的方法是构造您自己的 Entry 对象。

package main

import (

    "context"

    "encoding/json"

    "fmt"

    "google.golang.org/grpc"

    "google.golang.org/grpc/metadata"

    "log"

    "os"

    "strings"

)

// LogSeverity is used to map the logging levels consistent with Google Cloud Logging.

type LogSeverity string

const (

    // LogSeverity_DEBUG Debug or trace information.

    LogSeverity_DEBUG LogSeverity = "DEBUG"

    // LogSeverity_INFO Routine information, such as ongoing status or performance.

    LogSeverity_INFO LogSeverity = "INFO"

    // LogSeverity_NOTICE Normal but significant events, such as start up, shut down, or

    // a configuration change.

    LogSeverity_NOTICE LogSeverity = "NOTICE"

    // LogSeverity_WARNING Warning events might cause problems.

    LogSeverity_WARNING LogSeverity = "WARNING"

    // LogSeverity_ERROR Error events are likely to cause problems.

    LogSeverity_ERROR LogSeverity = "ERROR"

    // LogSeverity_CRITICAL Critical events cause more severe problems or outages.

    LogSeverity_CRITICAL LogSeverity = "CRITICAL"

    // LogSeverity_ALERT A person must take an action immediately.

    LogSeverity_ALERT LogSeverity = "ALERT"

    // LogSeverity_EMERGENCY One or more systems are unusable.

    LogSeverity_EMERGENCY LogSeverity = "EMERGENCY"

)

// Entry defines a log entry.

// If logs are provided in this format, Google Cloud Logging automatically

// parses the attributes into their LogEntry format as per

// https://cloud.google.com/logging/docs/reference/v2/rest/v2/LogEntry which then automatically

// makes the logs available in Google Cloud Logging and Tracing.

type Entry struct {

    Message  string      `json:"message"`

    Severity LogSeverity `json:"severity,omitempty"`

    Trace    string      `json:"logging.googleapis.com/trace,omitempty"`

    // To extend details sent to the logs, you may add the attributes here.

    //MyAttr1 string `json:"component,omitempty"`

}

// String renders an entry structure to the JSON format expected by Cloud Logging.

func (e Entry) String() string {

    // Defaults to INFO level.

    if e.Severity == "" {

        e.Severity = LogSeverity_INFO

    }

    // if Development is local then print out all logs

    if os.Getenv("ENV") == "LOCAL" {

        var prefix string

        switch e.Severity {

        case LogSeverity_DEBUG:

            prefix = colorize("DBG:      ", 90)

        case LogSeverity_INFO:

            prefix = colorize("INFO:     ", 32)

        case LogSeverity_NOTICE:

            prefix = colorize("NOTICE:   ", 34)

        case LogSeverity_WARNING:

            prefix = colorize("WARNING:  ", 33)

        case LogSeverity_ERROR:

            prefix = colorize("ERROR:    ", 31)

        case LogSeverity_ALERT:

            prefix = colorize("ALERT:    ", 91)

        case LogSeverity_CRITICAL:

            prefix = colorize("CRITICAL: ", 41)

        case LogSeverity_EMERGENCY:

            prefix = colorize("EMERGENCY:", 101)

        }

        return prefix + " " + e.Message

    } else {

        out, err := json.Marshal(e)

        if err != nil {

            log.Printf("json.Marshal: %v", err)

        }

        return string(out)

    }

}

// colorize returns the string s wrapped in ANSI code c

// Codes available at https://en.wikipedia.org/wiki/ANSI_escape_code#Colors

func colorize(s interface{}, c int) string {

    return fmt.Sprintf("\x1b[%dm%v\x1b[0m", c, s)

}

使用 Google Cloud 的特殊字段可以与其 Cloud Logging 产品更紧密地集成。