OpenTelemetry

Echo OpenTelemetry 是一个为 HTTP 请求提供 OpenTelemetry 插桩的中间件。

OpenTelemetry 是一组开源工具，为云原生应用提供插桩能力。

用法

使用 Go modules 添加 OpenTelemetry 中间件依赖：

go get github.com/labstack/echo-otel/v5

导入中间件和 OpenTelemetry trace API：

import (
  echootel "github.com/labstack/echo-otel/v5"
  "go.opentelemetry.io/otel/trace"
)

使用完整配置注册它：

e.Use(echootel.NewMiddlewareWithConfig(echootel.Config{
  ServerName:     "my-server",
  TracerProvider: tp,

  //Skipper:             nil,
  //OnNextError:         nil,
  //OnExtractionError:   nil,
  //MeterProvider:       nil,
  //Propagators:         nil,
  //SpanStartOptions:    nil,
  //SpanStartAttributes: nil,
  //SpanEndAttributes:   nil,
  //MetricAttributes:    nil,
  //Metrics:             nil,
}))

配置选项请参见 Config struct。

只提供服务器名称，以简化形式添加中间件：

e.Use(echootel.NewMiddleware("app.example.com"))

带配置选项添加中间件：

e.Use(echootel.NewMiddlewareWithConfig(echootel.Config{
  TracerProvider: tp,
}))

从 Echo 上下文获取 tracer：

tracer, err := echo.ContextGet[trace.Tracer](c, echootel.TracerKey)

示例

example 会把 spans 导出到 stdout，但你可以使用任何 exporter（OTLP 等）。请参见 OpenTelemetry exporters 文档。

API 参考

Config · github.com/labstack/echo-otel/[email protected]

字段说明由英文源码注释生成。

包源码中的字段
字段	类型	说明	源码
`ServerName`	`string`	ServerName is set as `server.address` and `server.port` span attributes. They are not added to metrics by default (Opt-In in the semantic conventions); add them with MetricAttributes if needed. Example: "api.example.com" or "example.com:8080". Without a port, `server.port` is not set. If known, this value must be set to the server’s canonical (primary) name. For example, in Apache this corresponds to the ServerName directive (https://httpd.apache.org/docs/2.4/mod/core.html#servername), and in NGINX to the server_name directive (http://nginx.org/en/docs/http/ngx_http_core_module.html#server_name). More generally, the primary server name is the host header value that maps to the HTTP server’s default virtual host. It must include the hostname, and if the server is accessed via a non-default port, the port must be appended using the standard ":port" suffix. If the primary server name is unknown, this field should be set to an empty string. In that case, Request.Host will be used to resolve the effective server name and port. Request.Host is chosen by the client.	L50
`Skipper`	`middleware.Skipper`	Skipper defines a function to skip middleware.	L53
`OnNextError`	`OnErrorFunc`	OnNextError is used to specify how errors returned from the next middleware / handler are handled.	L56
`OnExtractionError`	`OnErrorFunc`	OnExtractionError is used to specify how errors returned from request extraction are handled.	L59
`TracerProvider`	`oteltrace.TracerProvider`	TracerProvider allows overriding the default tracer provider.	L62
`MeterProvider`	`metric.MeterProvider`	MeterProvider allows overriding the default meter provider.	L65
`Propagators`	`propagation.TextMapPropagator`	Propagators allow overriding the default propagators.	L68
`SpanStartOptions`	`[]oteltrace.SpanStartOption`	SpanStartOptions configures an additional set of trace.SpanStartOptions, which are applied to each new span.	L71
`SpanStartAttributes`	`AttributesFunc`	SpanStartAttributes is used to extract additional attributes from the echo.Context and return them as a slice of attribute.KeyValue.	L75
`SpanEndAttributes`	`AttributesFunc`	SpanEndAttributes is used to extract additional attributes from the echo.Context and return them as a slice of attribute.KeyValue.	L79
`MetricAttributes`	`MetricAttributesFunc`	MetricAttributes is used to compose attributes just before Metrics.Record call.	L82
`Metrics`	`MetricsRecorder`	Metrics is used to record custom metrics instead of default.	L85

包源码中的函数
类型	源码
`func NewMiddleware(serverName string) echo.MiddlewareFunc`	L105
`func NewMiddlewareWithConfig(config Config) echo.MiddlewareFunc`	L110