This commit consists of:
1) Provide a kafka client to publish events to kafka brokers
2) Provide zookeeper and kafka docker containers for local testing,
will not be present in production
3) Sends a regular heartbeat to the kafka broker from voltha to
exercise all the components
4) Provides a basic kafka consumeri (requires kafka-python to be
installed) to read the messages off the local kafka broker -
this time it is only heartbeat messages
diff --git a/kafka/start-kafka.sh b/kafka/start-kafka.sh
new file mode 100755
index 0000000..cd437fb
--- /dev/null
+++ b/kafka/start-kafka.sh
@@ -0,0 +1,67 @@
+#!/bin/bash
+
+if [[ -z "$KAFKA_PORT" ]]; then
+ export KAFKA_PORT=9092
+fi
+if [[ -z "$KAFKA_ADVERTISED_PORT" ]]; then
+ export KAFKA_ADVERTISED_PORT=$(docker port `hostname` $KAFKA_PORT | sed -r "s/.*:(.*)/\1/g")
+fi
+if [[ -z "$KAFKA_BROKER_ID" ]]; then
+ # By default auto allocate broker ID
+ export KAFKA_BROKER_ID=-1
+fi
+if [[ -z "$KAFKA_LOG_DIRS" ]]; then
+ export KAFKA_LOG_DIRS="/kafka/kafka-logs-$HOSTNAME"
+fi
+if [[ -z "$KAFKA_ZOOKEEPER_CONNECT" ]]; then
+ export KAFKA_ZOOKEEPER_CONNECT=$(env | grep ZK.*PORT_2181_TCP= | sed -e 's|.*tcp://||' | paste -sd ,)
+fi
+
+if [[ -n "$KAFKA_HEAP_OPTS" ]]; then
+ sed -r -i "s/(export KAFKA_HEAP_OPTS)=\"(.*)\"/\1=\"$KAFKA_HEAP_OPTS\"/g" $KAFKA_HOME/bin/kafka-server-start.sh
+ unset KAFKA_HEAP_OPTS
+fi
+
+if [[ -z "$KAFKA_ADVERTISED_HOST_NAME" && -n "$HOSTNAME_COMMAND" ]]; then
+ export KAFKA_ADVERTISED_HOST_NAME=$(eval $HOSTNAME_COMMAND)
+fi
+
+for VAR in `env`
+do
+ if [[ $VAR =~ ^KAFKA_ && ! $VAR =~ ^KAFKA_HOME ]]; then
+ kafka_name=`echo "$VAR" | sed -r "s/KAFKA_(.*)=.*/\1/g" | tr '[:upper:]' '[:lower:]' | tr _ .`
+ env_var=`echo "$VAR" | sed -r "s/(.*)=.*/\1/g"`
+ if egrep -q "(^|^#)$kafka_name=" $KAFKA_HOME/config/server.properties; then
+ sed -r -i "s@(^|^#)($kafka_name)=(.*)@\2=${!env_var}@g" $KAFKA_HOME/config/server.properties #note that no config values may contain an '@' char
+ else
+ echo "$kafka_name=${!env_var}" >> $KAFKA_HOME/config/server.properties
+ fi
+ fi
+done
+
+if [[ -n "$CUSTOM_INIT_SCRIPT" ]] ; then
+ eval $CUSTOM_INIT_SCRIPT
+fi
+
+
+KAFKA_PID=0
+
+# see https://medium.com/@gchudnov/trapping-signals-in-docker-containers-7a57fdda7d86#.bh35ir4u5
+term_handler() {
+ echo 'Stopping Kafka....'
+ if [ $KAFKA_PID -ne 0 ]; then
+ kill -s TERM "$KAFKA_PID"
+ wait "$KAFKA_PID"
+ fi
+ echo 'Kafka stopped.'
+ exit
+}
+
+
+# Capture kill requests to stop properly
+trap "term_handler" SIGHUP SIGINT SIGTERM
+create-topics.sh &
+$KAFKA_HOME/bin/kafka-server-start.sh $KAFKA_HOME/config/server.properties &
+KAFKA_PID=$!
+
+wait