Add JMeter example application (#51)

* Add JMeter example

* Add OpenEnergyBadges

* Pin Docker images with hash

* Improve JMeter test plan

jmeter/README.md

@@ -0,0 +1,30 @@
+# JMeter
+
+[Apache JMeter](https://jmeter.apache.org/) is a load and performance testing tool.
+This example demonstrates how to use JMeter to execute a test plan that makes HTTP requests to a web application.
+
+It is based on a customized [JMeter Docker image](https://hub.docker.com/r/t2project/jmeter).
+
+As an example web application the reference application [T2-Project](https://t2-documentation.readthedocs.io) is used.
+
+## JMeter Execution
+
+JMeter gets executed as part of the flow in `usage_scenario.yml` with the following command:
+
+```bash
+jmeter -Jhostname=gcb-backend -Jport=8080 -JnumExecutions=1 -JnumUser=1 -JrampUp=0 -JnumProducts=1 -JthinkTimeMin=0 -JthinkTimeAdditionalRange=0 -JpauseBeforeExecution=0 -JpauseAfterExecution=0 -JloggingEnabled=true -n -t /tmp/repo/jmeter-test-plan.jmx
+```
+
+`hostname`, `port`, `numExecutions`, `numUser`, `rampUp`, `numProducts`, `thinkTimeMin`, `thinkTimeAdditionalRange`, `pauseBeforeExecution`, `pauseAfterExecution` and `loggingEnabled` are environment variables that get passed to JMeter. They are specific for this test plan (`jmeter-test-plan.jmx`).
+If you want to understand this test plan you can use the JMeter GUI and open the file `jmeter-test-plan.jmx`.
+
+## Running the measurement
+
+To check how to run the measurements check out our [Documentation](https://docs.green-coding.berlin)
+
+## OpenEnergyBadge
+
+These badges show the energy cost for running this code on a single machine and the emissions per order (SCI score).
+
+<a href="https://metrics.green-coding.berlin/stats.html?id=207c1ae2-d2b5-4fc9-a6ea-b68c2f69073a"><img src="https://api.green-coding.berlin/v1/badge/single/207c1ae2-d2b5-4fc9-a6ea-b68c2f69073a?metric=RAPL"></a>
+<a href="https://metrics.green-coding.berlin/stats.html?id=207c1ae2-d2b5-4fc9-a6ea-b68c2f69073a"><img src="https://api.green-coding.berlin/v1/badge/single/207c1ae2-d2b5-4fc9-a6ea-b68c2f69073a?metric=SCI"></a>

jmeter/compose.yml

@@ -0,0 +1,36 @@
+---
+version: "2"
+services:
+  gcb-postgres:
+    image: postgres:15.4
+    environment:
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: postgres
+    networks:
+      - t2-network
+  gcb-mongo:
+    image: mongo:5.0
+    networks:
+      - t2-network
+  gcb-backend:
+    image: t2project/modulith@sha256:180c620862e6aa936f00245c04fe0510896c2c8059663e3f0fae2a76b7a56966
+    depends_on:
+      - gcb-postgres
+      - gcb-mongo
+    environment:
+      MONGO_HOST: gcb-mongo
+      POSTGRES_HOST: gcb-postgres
+      SPRING_PROFILES_ACTIVE: gmt
+    networks:
+      - t2-network
+  gcb-jmeter:
+    image: t2project/jmeter@sha256:8d0543345f747ae512da2f0732fbd0ee760c7168415d2dce87e77d42fd14390a
+    environment:
+      JVM_XMN: 100 # maximum nursery size
+      JVM_XMS: 250 # initial heap size
+      JVM_XMX: 500 # maximum heap size
+    networks:
+      - t2-network
+
+networks:
+  t2-network: