Refactor and fix snmp exporter

docker/Makefile

@@ -24,7 +24,6 @@ jupyter-lab ec-sim grafana landing-page:
 	docker build -f $@/Dockerfile -t $(LOCAL_DOCKER_REGISTRY)/$@:$(TAG) $@
 
 snmp-exporter:
-	$(MAKE) -C snmp-exporter all
 	docker build -f $@/Dockerfile -t $(LOCAL_DOCKER_REGISTRY)/$@:$(TAG) $@
 
 dsconfig:

docker/snmp-exporter/Dockerfile

-FROM prom/snmp-exporter:latest
+FROM alpine:3 AS mibs
+RUN apk add --no-cache curl make sed
+ADD https://github.com/prometheus/snmp_exporter.git /src
+WORKDIR /src/generator
+RUN make mibs
 
-# snmp.yml is generated from generator.yml through make
-COPY snmp.yml /etc/snmp_exporter/snmp.yml
+FROM prom/snmp-generator:main AS generator
+COPY --from=mibs /src/generator/mibs /opt/mibs
+COPY lofar_mibs /tmp/lofar_mibs
+COPY generator.yml /opt/generator.yml
+RUN cp /tmp/lofar_mibs/* /opt/mibs/
+WORKDIR /opt
+RUN /bin/generator -m /opt/mibs --fail-on-parse-errors generate
+
+FROM prom/snmp-exporter:main
+COPY --from=generator /opt/snmp.yml /etc/snmp_exporter/snmp.yml

docker/snmp-exporter/Makefile

-.PHONY: all clean
-
-LOFAR_MIBS := $(wildcard lofar_mibs/*)
-CACHED_MIBS := $(wildcard snmp_exporter_mibs_cache/*) $(wildcard snmp_exporter_mibs_cache/.???*)
-
-all: snmp.yml
-
-clean:
-	rm -rf tmp
-
-tmp/Dockerfile: clean
-	git clone https://github.com/prometheus/snmp_exporter tmp
-
-snmp.yml: generator.yml ${LOFAR_MIBS} tmp/Dockerfile
-	cp generator.yml tmp/generator/
-	cp ${CACHED_MIBS} tmp/generator/mibs/
-	cp ${LOFAR_MIBS} tmp/generator/mibs/
-	(cd tmp/generator && make docker-generate)
-	cp tmp/generator/snmp.yml snmp.yml