logger

README

grpc-elasticsearch-logger

Logger for gRPC server to elasticsearch with elastic APM trace ID

Documentation

Overview

Package logger is used to log all intercepted unary and stream calls. The package exports the `NewLogger` function which sets up a logger with the elogrus hook and returns it.

The logger can be configured using environment variables:

LOG_LEVEL (default: "error") - Defines the log level of the logger, possible values:

"panic", "fatal", "error", "warn", "warning", "info", "debug", "trace"

LOG_INDEX (default: "log") - Defines the index to which the logs would be indexed to, the logs would be indexed to index pattern LOG_INDEX-*, where * is the current day's date in the format 'YYYY.MM.DD'

ELASTICSEARCH_URL (default: http://localhost:9200) - Defines the url of the elasticsearch server to index the logs to.

HOST_NAME (default: executable name) - Defines the host name of the server that is using the logger, which will be logged under 'Host' field.

There's the `WithElasticsearchServerLogger` function which sets up a `grpc.ServerOption` to intercept streams and unary calls with `*logrus.Entry` of the logger, created with `NewLogger`, and the options given to it. Returns the `grpc.ServerOption` which will be used in `grpc.NewServer` to log all incoming stream and unary calls. It also sets up the APM agent's unary server interceptor to log metrics to elastic APM.

The function `ExtractTraceParent` gets a `context.Context` which holds the "Elastic-Apm-Traceparent", which is the HTTP header for trace propagation, and returns the trace id.

Index

• func DefaultExtractInitialRequestDecider(ctx context.Context, fullMethodName string, servingObject interface{}) bool
• func DefaultServerPayloadLoggingDecider(ctx context.Context, fullMethodName string, servingObject interface{}) bool
• func ExtractTraceParent(ctx context.Context) string
• func IgnoreMethodServerPayloadLoggingDecider(fullIgnoredMethodName string) grpc_logging.ServerPayloadLoggingDecider
• func IgnoreMethodsServerPayloadLoggingDecider(fullIgnoredMethodNames ...string) grpc_logging.ServerPayloadLoggingDecider
• func NewLogger() *logrus.Logger
• func RequestExtractor(entry *logrus.Entry, decider func(string) bool) grpc_ctxtags.RequestFieldExtractorFunc
• func WithElasticsearchServerLogger(logrusEntry *logrus.Entry, ...) []grpc.ServerOption
• type JSONPbMarshaller
  • func (j *JSONPbMarshaller) MarshalJSON() ([]byte, error)

Functions

func DefaultExtractInitialRequestDecider

func DefaultExtractInitialRequestDecider(
	ctx context.Context,
	fullMethodName string,
	servingObject interface{}) bool

DefaultExtractInitialRequestDecider logs every initial request, for unary and streams.

func DefaultServerPayloadLoggingDecider

func DefaultServerPayloadLoggingDecider(
	ctx context.Context,
	fullMethodName string,
	servingObject interface{}) bool

DefaultServerPayloadLoggingDecider logs every payload.

func ExtractTraceParent

func ExtractTraceParent(ctx context.Context) string

ExtractTraceParent gets a `context.Context` which holds the "Elastic-Apm-Traceparent", which is the HTTP header for trace propagation, and returns the trace id.

func IgnoreMethodServerPayloadLoggingDecider

func IgnoreMethodServerPayloadLoggingDecider(
	fullIgnoredMethodName string,
) grpc_logging.ServerPayloadLoggingDecider

IgnoreMethodServerPayloadLoggingDecider ignores logging the payload of method that is equal to fullIgnoredMethodName.

func IgnoreMethodsServerPayloadLoggingDecider

func IgnoreMethodsServerPayloadLoggingDecider(
	fullIgnoredMethodNames ...string,
) grpc_logging.ServerPayloadLoggingDecider

IgnoreMethodsServerPayloadLoggingDecider ignores logging the payload of method that is equal to any string of fullIgnoredMethodNames.

func NewLogger

func NewLogger() *logrus.Logger

NewLogger creates a `*logrus.Logger` with `elogrus` hook, which logs to elasticsearch, and returns it.

func RequestExtractor

func RequestExtractor(entry *logrus.Entry, decider func(string) bool) grpc_ctxtags.RequestFieldExtractorFunc

RequestExtractor extracts the request and logs it as json under the key "grpc.request.content". Pass decider function to not extract the requests for certain methods.

func WithElasticsearchServerLogger

func WithElasticsearchServerLogger(
	logrusEntry *logrus.Entry,
	serverPayloadLoggingDecider grpc_logging.ServerPayloadLoggingDecider,
	extractInitialRequestDecider func(string) bool,
	opts ...grpc_logrus.Option,
) []grpc.ServerOption

WithElasticsearchServerLogger sets up a `grpc.ServerOption` to intercept streams with `*logrus.Entry` of the logger, created with `NewLogger`, and the options given to it. Returns the `grpc.ServerOption` which will be used in `grpc.NewServer` to log all incoming stream calls.

Types

type JSONPbMarshaller

type JSONPbMarshaller struct {
	proto.Message
}

JSONPbMarshaller is a struct used to marshal a protobuf message to JSON.

func (*JSONPbMarshaller) MarshalJSON

func (j *JSONPbMarshaller) MarshalJSON() ([]byte, error)

MarshalJSON marshals a protobuf message to JSON.