Add method to set fluentbit hook (#3140)

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

pkg/log/log.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"io"
+	"net/url"
 	"os"
 	"strings"
 	"time"
@@ -32,6 +33,12 @@ const (
 	LevelEnvName = "LOG_LEVEL"
 )
 
+var (
+	ErrEndpointNotSet = errors.New("fluentbit endpoint not set")
+	ErrNonTCPEndpoint = errors.New("fluentbit endpoint scheme must be tcp")
+	ErrPathSet        = errors.New("fluentbit endpoint path is set")
+)
+
 // OutputSink describes the current output sink.
 type OutputSink uint8
 
@@ -79,6 +86,22 @@ func SetOutput(sink OutputSink) error {
 	}
 }
 
+// SetFluentbitOutput sets the fluentbit output
+func SetFluentbitOutput(url *url.URL) error {
+	if url == nil || url.Host == "" {
+		return ErrEndpointNotSet
+	}
+	if url.Scheme != "tcp" {
+		return ErrNonTCPEndpoint
+	}
+	if url.Path != "" {
+		return ErrPathSet
+	}
+	hook := NewFluentbitHook(url.Host)
+	log.AddHook(hook)
+	return nil
+}
+
 var envVarFields field.Fields
 
 // initEnvVarFields populates envVarFields with values from the host's environment.

pkg/log/log_test.go

@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"net/url"
 	"os"
 	"sync"
 	"testing"
@@ -226,6 +227,52 @@ func (s *LogSuite) TestCloneGlobalLogger(c *check.C) {
 	c.Assert(hook.capturedMessages[0].Message, check.Equals, "Test message")
 }
 
+func (s *LogSuite) TestSetFluentbitOutput(c *check.C) {
+	for _, tc := range []struct {
+		desc string
+		url  *url.URL
+		err  error
+	}{
+		{
+			desc: "valid_url",
+			url: &url.URL{
+				Scheme: "tcp",
+				Host:   "something",
+			},
+		},
+		{
+			desc: "path_is_set",
+			url: &url.URL{
+				Scheme: "tcp",
+				Host:   "something",
+				Path:   "something",
+			},
+			err: ErrPathSet,
+		},
+		{
+			desc: "non_tcp_endpoint",
+			url: &url.URL{
+				Scheme: "http",
+				Host:   "something",
+				Path:   "something",
+			},
+			err: ErrNonTCPEndpoint,
+		},
+		{
+			desc: "empty_endpoint",
+			url:  &url.URL{},
+			err:  ErrEndpointNotSet,
+		},
+		{
+			desc: "nil_endpoint",
+			err:  ErrEndpointNotSet,
+		},
+	} {
+		err := SetFluentbitOutput(tc.url)
+		c.Assert(err, check.Equals, tc.err)
+	}
+}
+
 type logHook struct {
 	capturedMessages []*logrus.Entry
 }