Prometheus disabled by default

Author: mendhak

README.md

@@ -270,17 +270,18 @@ openssl pkcs12 -export -in cert.pem -inkey privkey.pem -out certpkcs12.pfx
 
 ## Prometheus Metrics
 
-By default the server uses `express-prom-bundle` middleware to expose http performance
-metrics in `/metrics`.
+To expose http performance metrics, set the `PROMETHEUS_ENABLED` environment variable to true, the metrics will be available at `/metrics`. This uses the [`express-prom-bundle`](https://github.com/jochen-schweizer/express-prom-bundle) middleware
+
 You can configure these metrics using the following variables:
 
-| Variable | Description | Default Value |
-| -------- | ----------- | ------------- |
-| PROMETHEUS_DISABLED    | Toggles off the prometheus middleware | false |
-| PROMETHEUS_WITH_PATH   | Partitions the metrics by the requested path | false |
-| PROMETHEUS_WITH_METHOD | Partitions the metrics by HTTP method | true |
-| PROMETHEUS_WITH_STATUS | Partitions the metrics by HTTP status | true |
-| PROMETHEUS_METRIC_TYPE | Sets the type of metric, histogram or summary | summary |
+| Variable                | Description                                   | Default Value |
+| ----------------------- | --------------------------------------------- | ------------- |
+| PROMETHEUS_ENABLED      | Toggles on the prometheus middleware          | false         |
+| PROMETHEUS_METRICS_PATH | The path at which the metrics will be visible | /metrics      |
+| PROMETHEUS_WITH_PATH    | Partitions the metrics by the requested path  | false         |
+| PROMETHEUS_WITH_METHOD  | Partitions the metrics by HTTP method         | true          |
+| PROMETHEUS_WITH_STATUS  | Partitions the metrics by HTTP status         | true          |
+| PROMETHEUS_METRIC_TYPE  | Sets the type of metric, histogram or summary | summary       |
 
 > Please check the middleware [documentation](https://github.com/jochen-schweizer/express-prom-bundle#options) for more details.
 

docker-compose.yml

@@ -5,7 +5,8 @@ services:
         environment:
             - HTTP_PORT=8888
             - HTTPS_PORT=9999
-            - PROMETHEUS_DISABLED=false
+            - PROMETHEUS_ENABLED=true
+            - PROMETHEUS_METRICS_PATH=/metrics
             - PROMETHEUS_WITH_PATH=false
             - PROMETHEUS_WITH_METHOD=true
             - PROMETHEUS_WITH_STATUS=true

index.js

@@ -9,7 +9,8 @@ const { promisify } = require('util');
 const promBundle = require("express-prom-bundle");
 
 const {
-  PROMETHEUS_DISABLED = false,
+  PROMETHEUS_ENABLED = false,
+  PROMETHEUS_METRICS_PATH = '/metrics',
   PROMETHEUS_WITH_PATH = false,
   PROMETHEUS_WITH_METHOD = 'true',
   PROMETHEUS_WITH_STATUS = 'true',
@@ -18,6 +19,7 @@ const {
 
 const sleep = promisify(setTimeout);
 const metricsMiddleware = promBundle({
+  metricsPath: PROMETHEUS_METRICS_PATH,
   includePath: (PROMETHEUS_WITH_PATH == 'true'),
   includeMethod: (PROMETHEUS_WITH_METHOD == 'true'),
   includeStatusCode: (PROMETHEUS_WITH_STATUS == 'true'),
@@ -27,7 +29,8 @@ const metricsMiddleware = promBundle({
 const app = express()
 app.set('json spaces', 2);
 app.set('trust proxy', ['loopback', 'linklocal', 'uniquelocal']);
-if(PROMETHEUS_DISABLED !== 'true') {
+
+if(PROMETHEUS_ENABLED === 'true') {
   app.use(metricsMiddleware);
 }
 

tests.sh

@@ -256,6 +256,7 @@ fi
 
 message " Stop containers "
 docker stop http-echo-tests
+sleep 5
 
 message " Start container with DISABLE_REQUEST_LOGS "
 docker run -d --rm -e DISABLE_REQUEST_LOGS=true --name http-echo-tests -p 8080:8080 -p 8443:8443 -t mendhak/http-https-echo
@@ -442,18 +443,39 @@ message " Stop containers "
 docker stop http-echo-tests
 sleep 5
 
-message " Start container with PROMETHEUS "
-docker run -d --rm -e --name http-echo-tests -p 8080:8080 -p 8443:8443 -t mendhak/http-https-echo
+message " Start container with PROMETHEUS disabled "
+docker run -d --rm --name http-echo-tests -p 8080:8080 -p 8443:8443 -t mendhak/http-https-echo
 sleep 5
 curl -s -k -X POST -d "tiramisu" https://localhost:8443/ > /dev/null
-METRICS_CHECK="$(curl -sk http://localhost:8080/metrics | grep http_request_duration_seconds_count | grep GET | cut -d' ' -f2)"
 
-if [ "$METRICS_CHECK" == "1" ]
+# grep for  http_request_duration_seconds_count ensure it is not present at /metric path
+
+METRICS_CHECK="$(curl -sk http://localhost:8080/metrics | grep -v http_request_duration_seconds_count )"
+
+if [[ "$METRICS_CHECK" == *"http_request_duration_seconds_count"* ]]
 then
-    passed "PROMETHEUS metrics are working"
+    failed "PROMETHEUS metrics are enabled"
+    exit 1
 else
-    failed "PROMETHEUS metrics are not working"
-    docker logs http-echo-tests
+    passed "PROMETHEUS metrics are disabled by default"
+fi
+
+message " Stop containers "
+docker stop http-echo-tests
+sleep 5
+
+message " Start container with PROMETHEUS enabled "
+docker run -d -e PROMETHEUS_ENABLED=true --rm --name http-echo-tests -p 8080:8080 -p 8443:8443 -t mendhak/http-https-echo
+sleep 5
+curl -s -k -X POST -d "tiramisu" https://localhost:8443/ > /dev/null
+
+METRICS_CHECK="$(curl -sk http://localhost:8080/metrics | grep http_request_duration_seconds_count )"
+
+if [[ "$METRICS_CHECK" == *"http_request_duration_seconds_count"* ]]
+then
+    passed "PROMETHEUS metrics are enabled"
+else
+    failed "PROMETHEUS metrics are disabled"
     exit 1
 fi