feat: add http endpoint to alter update/replacement config

config/config.go

@@ -12,6 +12,10 @@ import (
 	"strings"
 )
 
+var (
+	Config Specification
+)
+
 // Specification is the configuration specification for the extension. Configuration values can be applied
 // through environment variables. Learn more through the documentation of the envconfig package.
 // https://github.com/kelseyhightower/envconfig
@@ -29,7 +33,7 @@ type Specification struct {
 	ContainerPerPod    int `json:"containerPerPod" split_words:"true" required:"false" default:"2"`
 
 	AttributeUpdates   AttributeUpdateSpecifications    `split_words:"true" required:"false" default:"[]"`
-	TargetReplacements TargetReplacementsSpecifications `split_words:"true" required:"false" default:""`
+	TargetReplacements TargetReplacementsSpecifications `split_words:"true" required:"false" default:"[]"`
 
 	DiscoveryAttributesExcludesContainer            []string `json:"discoveryAttributesExcludesContainer" split_words:"true" required:"false"`
 	DiscoveryAttributesExcludesEc2                  []string `json:"discoveryAttributesExcludesEc2" split_words:"true" required:"false"`
@@ -64,7 +68,13 @@ func IsPodZero() bool {
 }
 
 type AttributeUpdateSpecifications []AttributeUpdateSpecification
-type TargetReplacementsSpecifications []TargetReplacementsSpecification
+
+type AttributeUpdateSpecification struct {
+	Type          string  `json:"type" split_words:"true"`
+	AttributeName string  `json:"attributeName" split_words:"true"`
+	Rate          float64 `json:"rate" split_words:"true"`
+	Interval      int     `json:"interval" split_words:"true"`
+}
 
 func (s *AttributeUpdateSpecifications) Decode(value string) error {
 	var specs []AttributeUpdateSpecification
@@ -76,15 +86,8 @@ func (s *AttributeUpdateSpecifications) Decode(value string) error {
 	return nil
 }
 
-type AttributeUpdateSpecification struct {
-	Type          string  `json:"type" split_words:"true"`
-	AttributeName string  `json:"attributeName" split_words:"true"`
-	Rate          float64 `json:"rate" split_words:"true"`
-	Interval      int     `json:"interval" split_words:"true"`
-}
-
-func (s *TargetReplacementsSpecification) Decode(value string) error {
-	var spec TargetReplacementsSpecification
+func (s *AttributeUpdateSpecification) Decode(value string) error {
+	var spec AttributeUpdateSpecification
 	err := json.Unmarshal([]byte(value), &spec)
 	if err != nil {
 		return fmt.Errorf("invalid json: %w", err)
@@ -93,15 +96,33 @@ func (s *TargetReplacementsSpecification) Decode(value string) error {
 	return nil
 }
 
+type TargetReplacementsSpecifications []TargetReplacementsSpecification
+
 type TargetReplacementsSpecification struct {
 	Type     string `json:"type" split_words:"true"`
 	Count    int    `json:"count" split_words:"true"`
 	Interval int    `json:"interval" split_words:"true"`
 }
 
-var (
-	Config Specification
-)
+func (s *TargetReplacementsSpecifications) Decode(value string) error {
+	var specs []TargetReplacementsSpecification
+	err := json.Unmarshal([]byte(value), &specs)
+	if err != nil {
+		return fmt.Errorf("invalid json: %w", err)
+	}
+	*s = specs
+	return nil
+}
+
+func (s *TargetReplacementsSpecification) Decode(value string) error {
+	var spec TargetReplacementsSpecification
+	err := json.Unmarshal([]byte(value), &spec)
+	if err != nil {
+		return fmt.Errorf("invalid json: %w", err)
+	}
+	*s = spec
+	return nil
+}
 
 func ParseConfiguration() {
 	err := envconfig.Process("steadybit_extension", &Config)

extloadtest/discovery.go

@@ -1,13 +1,19 @@
+// SPDX-License-Identifier: MIT
+// SPDX-FileCopyrightText: 2024 Steadybit GmbH
+
 package extloadtest
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
+	"github.com/procyon-projects/chrono"
 	"github.com/rs/zerolog/log"
 	"github.com/steadybit/action-kit/go/action_kit_api/v2"
 	"github.com/steadybit/action-kit/go/action_kit_sdk"
 	"github.com/steadybit/discovery-kit/go/discovery_kit_api"
 	"github.com/steadybit/discovery-kit/go/discovery_kit_sdk"
+	"github.com/steadybit/extension-kit/exthttp"
 	"github.com/steadybit/extension-kit/extutil"
 	"github.com/steadybit/extension-loadtest/config"
 	"net/http"
@@ -302,3 +308,35 @@ func (t *TargetData) RegisterRecreateActions() {
 		},
 	))
 }
+
+func (t *TargetData) RegisterConfigUpdateHandlers() {
+	exthttp.RegisterHttpHandler("/config/targetReplacements", t.updateConfigHandler(&config.Config.TargetReplacements))
+	exthttp.RegisterHttpHandler("/config/attributeUpdates", t.updateConfigHandler(&config.Config.AttributeUpdates))
+}
+
+func (t *TargetData) updateConfigHandler(config interface{}) exthttp.Handler {
+	return func(w http.ResponseWriter, r *http.Request, body []byte) {
+		if r.Method == http.MethodPost {
+			clone := extutil.JsonMangle(config)
+			err := json.Unmarshal(body, clone)
+			if err != nil {
+				w.WriteHeader(400)
+				_, _ = w.Write([]byte(err.Error()))
+			}
+			config = clone
+			t.rescheduleUpdates()
+			exthttp.WriteBody(w, config)
+		} else if r.Method == http.MethodGet {
+			exthttp.WriteBody(w, config)
+		} else {
+			w.WriteHeader(405)
+		}
+	}
+}
+
+func (t *TargetData) rescheduleUpdates() {
+	log.Info().Msg("Stopping all scheduled updates")
+	scheduler.Shutdown()
+	scheduler = chrono.NewDefaultTaskScheduler()
+	t.ScheduleUpdates()
+}

main.go

@@ -44,6 +44,7 @@ func main() {
 	targetData.ScheduleUpdates()
 	targetData.RegisterDiscoveries()
 	targetData.RegisterRecreateActions()
+	targetData.RegisterConfigUpdateHandlers()
 
 	discovery_kit_sdk.Register(extloadtest.NewEnrichmentRuleProvider())