Support for metrics

README.md

@@ -89,6 +89,22 @@ pointing to the load balancer instance's CNS records. See the
 
 [2]: https://github.com/TritonDataCenter/triton-dehydrated?tab=readme-ov-file#how-to-use-inside-a-user-container-on-triton
 
+## Metrics polling
+
+If the `cloud.tritoncompute:metrics_acl` metadata key is not empty then the
+metrics endpoint will be enabled on port `8405`. The ACL must be an IP prefix
+(e.g., `198.51.100.0/24`). Multiple comma or space separated prefixes can be
+included.
+
+If the `cloud.tritoncompute:certificate_name` key is supplied then the metrics
+endpoint will be served via HTTPS. If the key is not supplied then the metrics
+encpoint will be served via HTTP.
+
+**Note:** The load balancer will respond to *all hosts*. on port `8405`. Hosts
+outside of the configured ACL will receive a `403` response. If you want the
+load balancer to not respond at all then you must also configure Cloud Firewall
+for the instance.
+
 ## Development
 
 Typically development is done by:

haproxy.cfg/000-global.cfg

@@ -13,6 +13,7 @@
 #                                                  #
 
 global
+    default-path config
     master-worker
     mworker-max-reloads 10
     log 127.0.0.1 len 4096 local0

reconfigure

@@ -18,7 +18,17 @@ fi
 
 TOP=$(cd "$(dirname "$0")"; pwd)
 # SMF doesn't give us a sane path.
-PATH=/$TOP/build/node/bin:/usr/local/sbin:/usr/local/bin:/opt/local/sbin:/opt/local/bin:/usr/sbin:/usr/bin:/sbin
+PATH=/$TOP/build/node/bin:/usr/local/sbin:/usr/local/bin:/opt/local/sbin:/opt/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
+
+stat_f="-c %s"
+
+# For testing
+if [[ "$OSTYPE" != "solaris2.11" ]]; then
+    shopt -s expand_aliases
+    # shellcheck disable=SC2139
+    alias mdata-get="${TOP}/tools/mock-mdata-get"
+    stat_f="-f %z"
+fi
 
 skel_config_dir="${TOP}/haproxy.cfg"
 real_config_dir=/opt/local/etc/haproxy.cfg
@@ -29,7 +39,7 @@ candidate_domains=$(mktemp /tmp/domains.txt.XXXXXX)
 
 config_is_different=true
 
-function ensure_haproxy {
+function do_ensure_haproxy {
     haproxy_state=$(svcs -Ho state haproxy)
     case "$haproxy_state" in
         disabled)
@@ -49,7 +59,29 @@ function ensure_haproxy {
     esac
 }
 
-function configure_haproxy {
+function do_configure_acl {
+    acl_file="${candidate_config_dir}/210-metrics_acl.txt"
+    # shellcheck disable=SC2020
+    mdata-get cloud.tritoncompute:metrics_acl | tr ' ,' '\n\n' > "$acl_file"
+    if [[ -f /opt/triton/ssl/default/fullchain.pem ]]; then
+        bind_tls="ssl crt /opt/triton/ssl/default/fullchain.pem"
+    fi
+    fsize=$(stat "$stat_f" "$acl_file")
+    if (( fsize > 0 )); then
+cat << EOF > "${candidate_config_dir}/200-metrics.cfg"
+frontend __cloud_tritoncompute__metrics
+  bind *:8405 $bind_tls
+  mode http
+  http-request deny if !{ src -f 210-metrics_acl.txt }
+  http-request use-service prometheus-exporter if { path /metrics }
+  no log
+EOF
+    else
+        rm -f "${acl_file:?}"
+    fi
+}
+
+function do_configure_haproxy {
     rsync -a "${skel_config_dir}/" "${candidate_config_dir}/"
     {
         printf '#                                                  #\n'
@@ -58,6 +90,7 @@ function configure_haproxy {
     } > "${candidate_config_dir}/100-services.cfg"
 
     "${TOP}/parser.js" > "${candidate_config_dir}/100-services.cfg"
+    do_configure_acl
 
     if diff -qr "${real_config_dir}" "${candidate_config_dir}"; then
         config_is_different=false
@@ -73,7 +106,7 @@ function configure_haproxy {
     rm -rf "${candidate_config_dir:?}"
 }
 
-function configure_tls {
+function do_configure_tls {
     cert_subject=$(mdata-get cloud.tritoncompute:certificate_name || true)
     (
         if [[ -n "$cert_subject" ]]; then
@@ -86,15 +119,15 @@ function configure_tls {
             ./dehydrated -c >> /var/log/triton-dehydrated.log 2>&1
         else
             echo 'No certificate name present. Generating self-signed.'
-            generate_self_signed_certificate
+            do_generate_self_signed_certificate
         fi
         if [[ -f $candidate_domains ]]; then
             rm -f "$candidate_domains"
         fi
     )
 }
 
-function generate_self_signed_certificate  {
+function do_generate_self_signed_certificate  {
     if [[ -f ${self_signed_cert_dir}/privkey.pem && \
           -f ${self_signed_cert_dir}/cert.pem ]]; then
         echo "TLS Certificate Exists"
@@ -111,6 +144,6 @@ function generate_self_signed_certificate  {
     fi
 }
 
-configure_haproxy
-configure_tls
-ensure_haproxy
+do_configure_tls
+do_configure_haproxy
+do_ensure_haproxy

tools/mock-mdata-get

@@ -25,6 +25,8 @@ case $1 in
         echo 'Foo.exAmpLe.Com' ;;
     cloud.tritoncompute:max_rs)
         echo '64' ;;
+    cloud.tritoncompute:metrics_acl)
+        echo '192.168.1.1/24 192.168.2.0/24,192.168.3.3' ;;
     *)
         exit 1
         ;;