Adds bom.json file to the snap docker images (#144)

When joining a Kubernetes cluster, k8sd tries to determine the
Kubernetes version by checking the bom.json file included in the
snap.

The docker template does not include that file, meaning that joining
control plane nodes will fail to join because of this.

The components are now built in the same stage, as it is required by
generate-bom.py.

Author: claudiubelu

templates/docker/Dockerfile

@@ -64,38 +64,35 @@ RUN bash -x /build/static-dqlite-deps/static-dqlite.sh
 ENV DQLITE_BUILD_SCRIPTS_DIR=/build/static-dqlite-deps
 
 ####################################################################################################
-## IMAGE(build-*): Build individual components
+## IMAGE(build-*): Build components
 
 ## k8sd build
 FROM builder-dqlite AS build-k8sd
 WORKDIR /src/k8s-snap/src/k8s
 RUN make static -j
 RUN mkdir -p /out/bin && mv ./bin/static/* /out/bin/
 
-## k8s-dqlite build
-FROM builder-dqlite AS build-k8s-dqlite
-RUN /src/k8s-snap/build-scripts/build-component.sh k8s-dqlite
-
-## cni build
-FROM builder AS build-cni
-RUN /src/k8s-snap/build-scripts/build-component.sh cni
-
-## containerd build
-FROM builder AS build-containerd
-RUN /src/k8s-snap/build-scripts/build-component.sh containerd
-
-## helm build
-FROM builder AS build-helm
-RUN /src/k8s-snap/build-scripts/build-component.sh helm
-
-## kubernetes build
-FROM builder AS build-kubernetes
+## components build
+FROM builder-dqlite AS build-components
+WORKDIR /src/k8s-snap
+RUN ./build-scripts/build-component.sh k8s-dqlite
+RUN ./build-scripts/build-component.sh cni
+RUN ./build-scripts/build-component.sh containerd
+RUN ./build-scripts/build-component.sh helm
+RUN ./build-scripts/build-component.sh runc
+RUN ./build-scripts/build-component.sh pebble
+
+# build kubernetes
 ENV KUBERNETES_VERSION=${KUBERNETES_VERSION}
 RUN if [ -n "$KUBERNETES_VERSION" ]; then \
       echo "Overwriting Kubernetes version with $KUBERNETES_VERSION"; \
       echo "$KUBERNETES_VERSION" > /src/k8s-snap/build-scripts/components/kubernetes/version; \
     fi
-RUN  /src/k8s-snap/build-scripts/build-component.sh kubernetes
+RUN  ./build-scripts/build-component.sh kubernetes
+
+## generate bom.json file
+RUN apt-get install -y python3-yaml
+RUN bash -c "./build-scripts/generate-bom.py > /bom.json"
 
 ## kubernetes upgrade version build
 FROM builder AS build-kubernetes-upgrade-to
@@ -106,14 +103,6 @@ RUN if [ -n "$KUBERNETES_VERSION_UPGRADE_TO" ]; then \
     fi
 RUN  /src/k8s-snap/build-scripts/build-component.sh kubernetes
 
-## runc build
-FROM builder AS build-runc
-RUN /src/k8s-snap/build-scripts/build-component.sh runc
-
-## pebble build
-FROM builder AS build-pebble
-RUN /src/k8s-snap/build-scripts/build-component.sh pebble
-
 ####################################################################################################
 ## IMAGE(build-preload-images): Fetch OCI images that can be pre-loaded to containerd
 
@@ -146,15 +135,10 @@ RUN mkdir -p /var/lib/pebble/default/layers /snap/k8s/current /var/snap/k8s/comm
     && ln -sf "$(which true)" "$(which crictl)"
 
 ## NOTE(neoaggelos): Install binaries
-COPY --from=build-k8s-dqlite /out /snap/k8s/current
-COPY --from=build-runc /out /snap/k8s/current
-COPY --from=build-helm /out /snap/k8s/current
-COPY --from=build-containerd /out /snap/k8s/current
-COPY --from=build-cni /out /snap/k8s/current
-COPY --from=build-kubernetes /out /snap/k8s/current
+COPY --from=build-components /out /snap/k8s/current
+COPY --from=build-components /bom.json /snap/k8s/current/
 COPY --from=build-kubernetes-upgrade-to /out /k8s/upgrade
 COPY --from=build-k8sd /out /snap/k8s/current
-COPY --from=build-pebble /out /snap/k8s/current
 COPY --from=build-preload-images /out/images /var/snap/k8s/common/images
 
 ## NOTE(neoaggelos): Install k8s files