added correct consul template configuration

load_balancer/Dockerfile

@@ -1,16 +1,30 @@
-FROM nginx:1.23
-ARG    CONSUL_TEMPLATE_VERSION=0.30.0
-# we define an environment variable with the location of our Consul cluster. By default, it will try to resolve to
-# consul-client:8500 which would be the behavior if we have Consul running as a container in the same host and we link it to this
-# Nginx container (with the alias consul, of course). But this environment variable can also be overridden when we run the
-# container if we want to point somewhere else.
-ENV 	 CONSUL_URL consul-client:8500
-
-# download the latest version of Consul Template and we put it on /usr/local/bin
-ADD 	 https://releases.hashicorp.com/consul-template/${CONSUL_TEMPLATE_VERSION}/consul-template_${CONSUL_TEMPLATE_VERSION}_linux_amd64.zip /usr/bin/
-RUN 	 unzip /usr/bin/consul-template_${CONSUL_TEMPLATE_VERSION}_linux_amd64.zip && \
-    	 mv consul-template /usr/local/bin/consul-template && \
-    	 rm -rf /usr/bin/consul-template_${CONSUL_TEMPLATE_VERSION}_linux_amd64.zip
-
-
-COPY nginx.conf /etc/nginx/nginx.conf
+FROM nginx:1.23.1
+
+ARG CONSUL_TEMPLATE_VERSION=0.30.0
+
+# Set an environment variable for the location of the Consul
+# cluster. By default, it tries to resolve to consul-client:8500
+# which is the behavior if Consul is running as a container in the 
+# same host and linked to this NGINX container (with the alias 
+# consul, of course). But this environment variable can also be
+# overridden as the container starts if we want to resolve to
+# another address.
+
+ENV CONSUL_URL consul-client:8500
+
+# Download the specified version of Consul template
+ADD https://releases.hashicorp.com/consul-template/${CONSUL_TEMPLATE_VERSION}/consul-template_${CONSUL_TEMPLATE_VERSION}_linux_amd64.zip /tmp
+
+RUN apt-get update \
+  && apt-get install -y --no-install-recommends dumb-init unzip \
+  && unzip /tmp/consul-template_${CONSUL_TEMPLATE_VERSION}_linux_amd64.zip -d /usr/local/bin \
+  && rm -rf /tmp/consul-template_${CONSUL_TEMPLATE_VERSION}_linux_amd64.zip
+
+COPY consul-template-config.hcl ./consul-template-config.hcl
+COPY nginx.ctmpl /usr/templates/nginx.ctmpl
+
+EXPOSE 8085
+
+STOPSIGNAL SIGQUIT
+
+CMD ["dumb-init", "consul-template", "-config=consul-template-config.hcl"]

load_balancer/consul-template-config.hcl

@@ -0,0 +1,15 @@
+consul {
+  address = "consul-client:8500"
+
+  retry {
+    enabled  = true
+    attempts = 12
+    backoff  = "250ms"
+  }
+}
+template {
+  source      = "/usr/templates/nginx.ctmpl"
+  destination = "/etc/nginx/conf.d/default.conf"
+  perms       = 0600
+  command     = "if [ -e /var/run/nginx.pid ]; then nginx -s reload; else nginx; fi"
+}

load_balancer/nginx.ctmpl

@@ -0,0 +1,15 @@
+upstream messenger_service {
+    {{- range service "messenger" }}
+    server {{ .Address }}:{{ .Port }};
+    {{- end }}
+}
+
+server {
+    listen 8085;
+    server_name localhost;
+
+    location / {
+        proxy_pass http://messenger_service;
+        add_header Upstream-Host $upstream_addr;
+    }
+}