add prometheus support + prometheus/grafana docker compose

Author: derlin

.gitignore

@@ -36,4 +36,5 @@ out/
 
 ### Other ###
 other/cassandra/data
+other/monitoring/data
 logs

build.gradle.kts

@@ -55,11 +55,13 @@ dependencies {
 
     // metrics
     implementation("org.springframework.boot:spring-boot-starter-actuator")
+    implementation("io.micrometer:micrometer-registry-prometheus") // prometheus
 
     // kafka
     // see compatibility matrix at https://spring.io/projects/spring-kafka
     implementation("org.springframework.kafka:spring-kafka")
 
+
     // for XML support
     // implementation("com.fasterxml.jackson.dataformat:jackson-dataformat-xml")
 

other/monitoring/README.md

@@ -0,0 +1,41 @@
+# Monitoring with Prometheus + Grafana
+
+This folder contains a docker compose to monitor BBData API instances using Prometheus + Grafana.
+
+**IMPORTANT**: for this to work, the BBData API instances must be launched with the property `management.endpoint.prometheus.enabled=true`.
+
+## Setup and Run
+
+First, edit the file `config/prometheus.yml`:
+* set the different target instances, that is the list of `<HOST|IP>:<PORT>` where your applications are running 
+  (when development on Mac, use `host.docker.internal` to access bbdata-api running on localhost)
+* change the scraping interval, if you want to
+
+Once done, simply run from this directory the command:
+```bash
+docker-compose up -d
+```
+
+If you get an error of type **permission denied**, such as
+```text
+You may have issues with file permissions, [...]
+mkdir: cannot create directory '/var/lib/grafana/plugins': Permission denied
+```
+look at the permissions of the `data` folder (chown if needed), and use the `user: 'sid'` directive in `docker-compose.yml`.
+On linux, you can get you user sid by running `id -u`.
+
+## prometheus
+
+Prometheus can be accessed on port `9090`.
+
+
+## Grafana
+
+Grafana can be accessed on port `3000`.
+
+### First use
+
+* use default username/password: *admin/admin* (change it to admin/bbdata or whatever)
+* add prometheus data source: *Configuration* > *Add data source* > *Prometheus*, and set URL=`http://prometheus:9090`
+* add an open-source Spring Boot dashboard: *"+"* > *Import*: https://grafana.com/grafana/dashboards/10280
+* add the custom BBData dashboard using the same import wizard and load (or copy-paste) the JSON file `bbdata-dashboard-grafana.json`