don't read topic and consumer group id from runtime configuration

These won't be changing at runtime, so there's no need to complicate the
initialization by making these configurable. The topic's prefix is
configurable, and that's the part that will change from environment to
environment at runtime.

BACK-2554

Author: ewollesen

data/service/service/standard.go

@@ -483,22 +483,13 @@ func (s *Standard) initializeAlertsEventsHandler() error {
 		return err
 	}
 
-	// In addition to the CloudEventsConfig, additional specific config values
-	// are needed.
-	config := &struct {
-		KafkaAlertsTopics  []string `envconfig:"KAFKA_ALERTS_TOPICS" default:"alerts,deviceData.alerts"`
-		KafkaAlertsGroupID string   `envconfig:"KAFKA_ALERTS_CONSUMER_GROUP" required:"true"`
-	}{}
-	if err := envconfig.Process("", config); err != nil {
-		return errors.Wrap(err, "Unable to process envconfig")
-	}
-
+	topics := []string{"data.alerts", "data.deviceData.alerts"}
 	// Some kafka topics use a `<env>-` as a prefix. But MongoDB CDC topics are created with
 	// `<env>.`. This code is using CDC topics, so ensuring that a `.` is used for alerts events
 	// lines everything up as expected.
 	topicPrefix := strings.ReplaceAll(commonConfig.KafkaTopicPrefix, "-", ".")
-	prefixedTopics := make([]string, 0, len(config.KafkaAlertsTopics))
-	for _, topic := range config.KafkaAlertsTopics {
+	prefixedTopics := make([]string, 0, len(topics))
+	for _, topic := range topics {
 		prefixedTopics = append(prefixedTopics, topicPrefix+topic)
 	}
 
@@ -517,7 +508,7 @@ func (s *Standard) initializeAlertsEventsHandler() error {
 
 	runnerCfg := dataEvents.SaramaRunnerConfig{
 		Brokers: commonConfig.KafkaBrokers,
-		GroupID: config.KafkaAlertsGroupID,
+		GroupID: "alerts",
 		Topics:  prefixedTopics,
 		Sarama:  commonConfig.SaramaConfig,
 		MessageConsumer: &dataEvents.AlertsEventsConsumer{