cmd: build 'smbmetrics' as stand-alone executable

Bind main to metrics code to produce a stand-alone metrics-exporter
executable binary.

Signed-off-by: Shachar Sharon <[email protected]>

Author: synarete

Makefile

@@ -58,6 +58,45 @@ define yamls_reformat
 	YQ=$(YQ) $(CURDIR)/hack/yq-fixup-yamls.sh $(1)
 endef
 
+all: build
+
+# Build executable
+.PHONY: build
+build:
+	CGO_ENABLED=0 $(GO_CMD) build -o bin/smbmetrics \
+		-ldflags $(GOLDFLAGS) cmd/main.go
+
+# Run unit tests
+.PHONY: test
+test: build vet
+	$(GO_CMD) test ./... -coverprofile cover.out
+
+
+# Run go fmt to reformat code
+.PHONY: reformat
+reformat:
+	$(GO_CMD) fmt ./...
+
+# Run go vet against code
+.PHONY: vet
+vet: reformat
+	$(GO_CMD) vet ./...
+
+# Format yaml files for yamllint standard
+.PHONY: yaml-fmt
+yaml-fmt: yq
+	$(call yamls_reformat, $(CURDIR))
+
+# Check the code
+.PHONY: check check-golangci-lint check-format check-yaml
+
+check: check-golangci-lint vet check-yaml
+
+check-golangci-lint: golangci-lint
+	$(GOLANGCI_LINT) -c .golangci.yaml run ./...
+
+check-yaml:
+	$(YAMLLINT_CMD) -c ./.yamllint.yaml ./
 
 # Find or download auxiliary build tools
 .PHONY: build-tools golangci-lint yq

cmd/main.go

@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: Apache-2.0
+
+package main
+
+import (
+	"os"
+	goruntime "runtime"
+
+	"sigs.k8s.io/controller-runtime/pkg/log/zap"
+
+	"github.com/samba-in-kubernetes/smbmetrics/internal/metrics"
+)
+
+var (
+	// Version of the software at compile time.
+	Version = "(unset)"
+	// CommitID of the revision used to compile the software.
+	CommitID = "(unset)"
+)
+
+func main() {
+	log := zap.New(zap.UseDevMode(true))
+	log.Info("Initializing smbmetrics",
+		"ProgramName", os.Args[0],
+		"Version", Version,
+		"CommitID", CommitID,
+		"GoVersion", goruntime.Version())
+
+	loc, err := metrics.LocateSmbStatus()
+	if err != nil {
+		log.Error(err, "Failed to locate smbstatus")
+		os.Exit(1)
+	}
+	ver, err := metrics.RunSmbStatusVersion()
+	if err != nil {
+		log.Error(err, "Failed to run smbstatus")
+		os.Exit(1)
+	}
+	log.Info("Located smbstatus", "path", loc, "version", ver)
+
+	err = metrics.RunSmbMetricsExporter(log)
+	if err != nil {
+		os.Exit(1)
+	}
+}

go.mod

@@ -0,0 +1,10 @@
+module github.com/samba-in-kubernetes/smbmetrics
+
+go 1.16
+
+require (
+	github.com/go-logr/logr v0.4.0
+	github.com/prometheus/client_golang v1.11.1
+	github.com/stretchr/testify v1.7.0
+	sigs.k8s.io/controller-runtime v0.10.1
+)