|
| 1 | +# embedded-mongodb |
| 2 | + |
| 3 | +Sample Helidon MP project that includes multiple REST operations. |
| 4 | + |
| 5 | +## Build and run |
| 6 | + |
| 7 | + |
| 8 | +With JDK21 |
| 9 | +```bash |
| 10 | +mvn package |
| 11 | +java -jar target/embedded-mongodb.jar |
| 12 | +``` |
| 13 | + |
| 14 | +## Exercise the application |
| 15 | + |
| 16 | +Basic: |
| 17 | +``` |
| 18 | +curl -X GET http://localhost:8080/simple-greet |
| 19 | +Hello World! |
| 20 | +``` |
| 21 | + |
| 22 | + |
| 23 | +JSON: |
| 24 | +``` |
| 25 | +curl -X GET http://localhost:8080/greet |
| 26 | +{"message":"Hello World!"} |
| 27 | +
|
| 28 | +curl -X GET http://localhost:8080/greet/Joe |
| 29 | +{"message":"Hello Joe!"} |
| 30 | +
|
| 31 | +curl -X PUT -H "Content-Type: application/json" -d '{"greeting" : "Hola"}' http://localhost:8080/greet/greeting |
| 32 | +
|
| 33 | +curl -X GET http://localhost:8080/greet/Jose |
| 34 | +{"message":"Hola Jose!"} |
| 35 | +``` |
| 36 | + |
| 37 | + |
| 38 | + |
| 39 | +## Try health |
| 40 | + |
| 41 | +``` |
| 42 | +curl -s -X GET http://localhost:8080/health |
| 43 | +{"outcome":"UP",... |
| 44 | +
|
| 45 | +``` |
| 46 | + |
| 47 | + |
| 48 | +## Building a Native Image |
| 49 | + |
| 50 | +The generation of native binaries requires an installation of GraalVM 22.1.0+. |
| 51 | + |
| 52 | +You can build a native binary using Maven as follows: |
| 53 | + |
| 54 | +``` |
| 55 | +mvn -Pnative-image install -DskipTests |
| 56 | +``` |
| 57 | + |
| 58 | +The generation of the executable binary may take a few minutes to complete depending on |
| 59 | +your hardware and operating system. When completed, the executable file will be available |
| 60 | +under the `target` directory and be named after the artifact ID you have chosen during the |
| 61 | +project generation phase. |
| 62 | + |
| 63 | + |
| 64 | + |
| 65 | +## Try metrics |
| 66 | + |
| 67 | +``` |
| 68 | +# Prometheus Format |
| 69 | +curl -s -X GET http://localhost:8080/metrics |
| 70 | +# TYPE base:gc_g1_young_generation_count gauge |
| 71 | +. . . |
| 72 | +
|
| 73 | +# JSON Format |
| 74 | +curl -H 'Accept: application/json' -X GET http://localhost:8080/metrics |
| 75 | +{"base":... |
| 76 | +. . . |
| 77 | +``` |
| 78 | + |
| 79 | + |
| 80 | + |
| 81 | +## Building the Docker Image |
| 82 | + |
| 83 | +``` |
| 84 | +docker build -t embedded-mongodb . |
| 85 | +``` |
| 86 | + |
| 87 | +## Running the Docker Image |
| 88 | + |
| 89 | +``` |
| 90 | +docker run --rm -p 8080:8080 embedded-mongodb:latest |
| 91 | +``` |
| 92 | + |
| 93 | +Exercise the application as described above. |
| 94 | + |
| 95 | + |
| 96 | +## Run the application in Kubernetes |
| 97 | + |
| 98 | +If you don’t have access to a Kubernetes cluster, you can [install one](https://helidon.io/docs/latest/#/about/kubernetes) on your desktop. |
| 99 | + |
| 100 | +### Verify connectivity to cluster |
| 101 | + |
| 102 | +``` |
| 103 | +kubectl cluster-info # Verify which cluster |
| 104 | +kubectl get pods # Verify connectivity to cluster |
| 105 | +``` |
| 106 | + |
| 107 | +### Deploy the application to Kubernetes |
| 108 | + |
| 109 | +``` |
| 110 | +kubectl create -f app.yaml # Deploy application |
| 111 | +kubectl get pods # Wait for quickstart pod to be RUNNING |
| 112 | +kubectl get service embedded-mongodb # Get service info |
| 113 | +kubectl port-forward service/embedded-mongodb 8081:8080 # Forward service port to 8081 |
| 114 | +``` |
| 115 | + |
| 116 | +You can now exercise the application as you did before but use the port number 8081. |
| 117 | + |
| 118 | +After you’re done, cleanup. |
| 119 | + |
| 120 | +``` |
| 121 | +kubectl delete -f app.yaml |
| 122 | +``` |
| 123 | + |
| 124 | + |
| 125 | +## Building a Custom Runtime Image |
| 126 | + |
| 127 | +Build the custom runtime image using the jlink image profile: |
| 128 | + |
| 129 | +``` |
| 130 | +mvn package -Pjlink-image |
| 131 | +``` |
| 132 | + |
| 133 | +This uses the helidon-maven-plugin to perform the custom image generation. |
| 134 | +After the build completes it will report some statistics about the build including the reduction in image size. |
| 135 | + |
| 136 | +The target/embedded-mongodb-jri directory is a self contained custom image of your application. It contains your application, |
| 137 | +its runtime dependencies and the JDK modules it depends on. You can start your application using the provide start script: |
| 138 | + |
| 139 | +``` |
| 140 | +./target/embedded-mongodb-jri/bin/start |
| 141 | +``` |
| 142 | + |
| 143 | +Class Data Sharing (CDS) Archive |
| 144 | +Also included in the custom image is a Class Data Sharing (CDS) archive that improves your application’s startup |
| 145 | +performance and in-memory footprint. You can learn more about Class Data Sharing in the JDK documentation. |
| 146 | + |
| 147 | +The CDS archive increases your image size to get these performance optimizations. It can be of significant size (tens of MB). |
| 148 | +The size of the CDS archive is reported at the end of the build output. |
| 149 | + |
| 150 | +If you’d rather have a smaller image size (with a slightly increased startup time) you can skip the creation of the CDS |
| 151 | +archive by executing your build like this: |
| 152 | + |
| 153 | +``` |
| 154 | +mvn package -Pjlink-image -Djlink.image.addClassDataSharingArchive=false |
| 155 | +``` |
| 156 | + |
| 157 | +For more information on available configuration options see the helidon-maven-plugin documentation. |
| 158 | + |
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