From 1a376617faea10e814df217403f09e22f2f5ad6d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martynas=20Mickevi=C4=8Dius?= <self@2m.lt>
Date: Tue, 5 Jun 2018 13:59:36 +0300
Subject: [PATCH 1/2] Generic handling of _COMMAND substitutions

---
 docker-compose-scale.yaml | 21 +++++++++++++++++++++
 start-kafka.sh            | 38 +++++++++++++-------------------------
 2 files changed, 34 insertions(+), 25 deletions(-)
 create mode 100644 docker-compose-scale.yaml

diff --git a/docker-compose-scale.yaml b/docker-compose-scale.yaml
new file mode 100644
index 00000000..c610e30f
--- /dev/null
+++ b/docker-compose-scale.yaml
@@ -0,0 +1,21 @@
+version: '2'
+services:
+  zookeeper:
+    image: wurstmeister/zookeeper
+    ports:
+      - "2181:2181"
+  kafka:
+    build: .
+    ports:
+      - "9094"
+    environment:
+      INSIDE_HOSTNAME_COMMAND: "docker inspect -f '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' `hostname`"
+      HOSTNAME_COMMAND: "docker info | grep ^Name: | cut -d' ' -f 2"
+      PORT_COMMAND: "docker port `hostname` 9094 | cut -d: -f 2"
+      KAFKA_ADVERTISED_LISTENERS: INSIDE://_{INSIDE_HOSTNAME_COMMAND}:9092,OUTSIDE://_{HOSTNAME_COMMAND}:_{PORT_COMMAND}
+      KAFKA_LISTENERS: INSIDE://:9092,OUTSIDE://:9094
+      KAFKA_LISTENER_SECURITY_PROTOCOL_MAP: INSIDE:PLAINTEXT,OUTSIDE:PLAINTEXT
+      KAFKA_INTER_BROKER_LISTENER_NAME: INSIDE
+      KAFKA_ZOOKEEPER_CONNECT: zookeeper:2181
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock
diff --git a/start-kafka.sh b/start-kafka.sh
index 51567abf..d395bfe1 100755
--- a/start-kafka.sh
+++ b/start-kafka.sh
@@ -50,31 +50,19 @@ if [[ -n "$KAFKA_HEAP_OPTS" ]]; then
     unset KAFKA_HEAP_OPTS
 fi
 
-if [[ -n "$HOSTNAME_COMMAND" ]]; then
-    HOSTNAME_VALUE=$(eval "$HOSTNAME_COMMAND")
-
-    # Replace any occurences of _{HOSTNAME_COMMAND} with the value
-    IFS=$'\n'
-    for VAR in $(env); do
-        if [[ $VAR =~ ^KAFKA_ && "$VAR" =~ "_{HOSTNAME_COMMAND}" ]]; then
-            eval "export ${VAR//_\{HOSTNAME_COMMAND\}/$HOSTNAME_VALUE}"
-        fi
-    done
-    IFS=$ORIG_IFS
-fi
-
-if [[ -n "$PORT_COMMAND" ]]; then
-    PORT_VALUE=$(eval "$PORT_COMMAND")
-
-    # Replace any occurences of _{PORT_COMMAND} with the value
-    IFS=$'\n'
-    for VAR in $(env); do
-        if [[ $VAR =~ ^KAFKA_ && "$VAR" =~ "_{PORT_COMMAND}" ]]; then
-	    eval "export ${VAR//_\{PORT_COMMAND\}/$PORT_VALUE}"
-        fi
-    done
-    IFS=$ORIG_IFS
-fi
+IFS=$'\n'
+for COMMAND in $(env); do
+    if [[ $COMMAND =~ _COMMAND= ]]; then
+        COMMAND_KEY=${COMMAND%=*}
+        COMMAND_VALUE=$(eval "${COMMAND#*=}")
+        for VAR in $(env); do
+            if [[ $VAR =~ ^KAFKA_ && "$VAR" =~ "_{$COMMAND_KEY}" ]]; then
+                eval "export ${VAR//_\{$COMMAND_KEY\}/$COMMAND_VALUE}"
+            fi
+        done
+    fi
+done
+IFS=$ORIG_IFS
 
 if [[ -n "$RACK_COMMAND" && -z "$KAFKA_BROKER_RACK" ]]; then
     KAFKA_BROKER_RACK=$(eval "$RACK_COMMAND")

From 4921fc56cd190d6f8ee56930816b46e5403b0e46 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martynas=20Mickevi=C4=8Dius?= <self@2m.lt>
Date: Tue, 5 Jun 2018 14:58:40 +0300
Subject: [PATCH 2/2] Fix shellcheck errors

---
 start-kafka.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/start-kafka.sh b/start-kafka.sh
index d395bfe1..e7c89818 100755
--- a/start-kafka.sh
+++ b/start-kafka.sh
@@ -56,7 +56,7 @@ for COMMAND in $(env); do
         COMMAND_KEY=${COMMAND%=*}
         COMMAND_VALUE=$(eval "${COMMAND#*=}")
         for VAR in $(env); do
-            if [[ $VAR =~ ^KAFKA_ && "$VAR" =~ "_{$COMMAND_KEY}" ]]; then
+            if [[ $VAR =~ ^KAFKA_ && "$VAR" =~ _{$COMMAND_KEY} ]]; then
                 eval "export ${VAR//_\{$COMMAND_KEY\}/$COMMAND_VALUE}"
             fi
         done