Add the ability to get email notifications when haproxy detects a service

going down

haproxy.yaml

@@ -7,15 +7,41 @@ services:
       SYNC_BROADCAST_BACKEND_SERVER: "${SYNC_BROADCAST_BACKEND_SERVER:-api.hive.blog}"
       SYNC_BROADCAST_BACKEND_PORT: "${SYNC_BROADCAST_BACKEND_PORT:-443}"
       SYNC_BROADCAST_BACKEND_SSL: "${SYNC_BROADCAST_BACKEND_SSL:-ssl}"
+      HAPROXY_EMAIL_FROM: "${HAPROXY_EMAIL_FROM:-}"
+      HAPROXY_EMAIL_TO: "${HAPROXY_EMAIL_FROM:-}"
+      HAPROXY_EMAIL_LEVEL: "${HAPROXY_EMAIL_LEVEL:-notice}"
     volumes:
       - type: bind
         source: ./haproxy/haproxy.cfg
         target: /usr/local/etc/haproxy/haproxy.cfg
         read_only: true
+      - type: bind
+        source: ${HAPROXY_MAILER_CONFIG:-./haproxy/mailer.cfg}
+        target: /usr/local/etc/haproxy/_mailer.cfg
+        read_only: true
     networks:
       - haf-network
     healthcheck:
       test: wget -q --spider 127.0.0.1:8001 
+    depends_on:
+      smtp-relay:
+        condition: service_started
+        required: false
+      haf:
+        condition: service_started
+        required: false
+      balance-tracker-postgrest:
+        condition: service_started
+        required: false
+      hafah-postgrest:
+        condition: service_started
+        required: false
+      hivemind-server:
+        condition: service_started
+        required: false
+      block-explorer-postgrest:
+        condition: service_started
+        required: false
   haproxy-healthchecks:
     image: ${HAPROXY_HEALTHCHECKS_REGISTRY:-${HIVE_API_NODE_REGISTRY:-registry.hive.blog}/haf_api_node/haproxy-healthchecks}:${HAPROXY_HEALTHCHECKS_VERSION:-${HIVE_API_NODE_VERSION}}
     environment:
@@ -28,3 +54,17 @@ services:
       - haproxy-healthchecks
     networks:
       - haf-network
+  smtp-relay:
+    profiles:
+      - email
+    image: grafana/smtprelay
+    command:
+      - -hostname=${PUBLIC_HOSTNAME}
+      - -listen=0.0.0.0:25
+      - -allowed_nets= 
+      - -remote_host=${SMTP_HOST}
+      - -remote_user=${SMTP_USER}
+      - -remote_pass=${SMTP_PASS}
+      - -remote_auth=${SMTP_AUTH_TYPE:-plain}
+    networks:
+      - haf-network

haproxy/haproxy.cfg

@@ -7,26 +7,11 @@ global
   presetenv SYNC_BROADCAST_BACKEND_PORT 443
   presetenv SYNC_BROADCAST_BACKEND_SSL ssl 
 
-defaults
-  log     global
-  mode    http
-  option  httplog
-  option  dontlognull
-  option  forwardfor
-  option  http-server-close
-  option  log-health-checks
-  timeout connect 5s
-  timeout client  30s
-  timeout server  30s
-  timeout tunnel  1h
-  default-server init-addr last,libc,none resolvers docker check
-  #errorfile 400 /etc/haproxy/errors/400.http
-  #errorfile 403 /etc/haproxy/errors/403.http
-  #errorfile 408 /etc/haproxy/errors/408.http
-  #errorfile 500 /etc/haproxy/errors/500.http
-  #errorfile 502 /etc/haproxy/errors/502.http
-  #errorfile 503 /etc/haproxy/errors/503.http
-  #errorfile 504 /etc/haproxy/errors/504.http
+# DEFAULTS
+# do not put a defaults section here, the defaults section is included
+# from either the `mailer.cfg` or `no-mailer.cfg` files (only one of those
+# files is included, which one depends on your setup).  Make any changes 
+# to defaults in both of those files.
 
 resolvers docker
   parse-resolv-conf

haproxy/mailer.cfg

+mailers mta
+  mailer smtp smtp-relay:25
+
+defaults
+  log     global
+  mode    http
+  option  httplog
+  option  dontlognull
+  option  forwardfor
+  option  http-server-close
+  option  log-health-checks
+  timeout connect 5s
+  timeout client  30s
+  timeout server  30s
+  timeout tunnel  1h
+  default-server init-addr last,libc,none resolvers docker check
+  #errorfile 400 /etc/haproxy/errors/400.http
+  #errorfile 403 /etc/haproxy/errors/403.http
+  #errorfile 408 /etc/haproxy/errors/408.http
+  #errorfile 500 /etc/haproxy/errors/500.http
+  #errorfile 502 /etc/haproxy/errors/502.http
+  #errorfile 503 /etc/haproxy/errors/503.http
+  #errorfile 504 /etc/haproxy/errors/504.http
+  email-alert from donotreply@syncad.com
+  email-alert to efrias@syncad.com
+  email-alert mailers mta
+  email-alert level notice
+

haproxy/no-mailer.cfg

+defaults
+  log     global
+  mode    http
+  option  httplog
+  option  dontlognull
+  option  forwardfor
+  option  http-server-close
+  option  log-health-checks
+  timeout connect 5s
+  timeout client  30s
+  timeout server  30s
+  timeout tunnel  1h
+  default-server init-addr last,libc,none resolvers docker check
+  #errorfile 400 /etc/haproxy/errors/400.http
+  #errorfile 403 /etc/haproxy/errors/403.http
+  #errorfile 408 /etc/haproxy/errors/408.http
+  #errorfile 500 /etc/haproxy/errors/500.http
+  #errorfile 502 /etc/haproxy/errors/502.http
+  #errorfile 503 /etc/haproxy/errors/503.http
+  #errorfile 504 /etc/haproxy/errors/504.http