Check import order and formatting during linting (#121)

* Check import sort order during linting and fix issues.

* Add `fix-lint` target

* Clean up trailing whitespace

* Enable `gofmt` linter too

.golangci.yaml

@@ -1,10 +1,24 @@
 run:
   build-tags:
     - requires_docker
+
+linters:
+  enable:
+    - gci
+    - gofmt
+
 linters-settings:
   errcheck:
     # Use exclude-functions instead of exclude, since the GitHub Action's caching is broken.
     # When changing the file referenced by exclude, the GitHub Action may use an older cache
     # entry and ignore the changes in said file (thus breaking CI).
     exclude-functions:
       - (github.com/go-kit/log.Logger).Log
+
+  gci:
+    skip-generated: true
+    custom-order: true
+    sections:
+      - standard
+      - default
+      - prefix(github.com/grafana/rollout-operator)

Makefile

@@ -25,12 +25,12 @@ rollout-operator: $(GO_FILES) ## Build the rollout-operator binary
 rollout-operator-boringcrypto: $(GO_FILES) ## Build the rollout-operator binary with boringcrypto
 	GOEXPERIMENT=boringcrypto GOOS=$(GOOS) GOARCH=$(GOARCH) CGO_ENABLED=1 go build -tags netgo ./cmd/rollout-operator
 
-.PHONY: build-image 
+.PHONY: build-image
 build-image: clean ## Build the rollout-operator image
 	docker buildx build --load --platform linux/amd64 --build-arg revision=$(GIT_REVISION) -t rollout-operator:latest -t rollout-operator:$(IMAGE_TAG) .
 
 .PHONY: build-image-boringcrypto
-build-image-boringcrypto: clean ## Build the rollout-operator image with boringcrypto 
+build-image-boringcrypto: clean ## Build the rollout-operator image with boringcrypto
 	# Tags with the regular image repo for integration testing
 	docker buildx build --load --platform linux/amd64 --build-arg revision=$(GIT_REVISION) --build-arg BUILDTARGET=rollout-operator-boringcrypto -t rollout-operator:latest -t rollout-operator:$(IMAGE_TAG) .
 
@@ -66,6 +66,10 @@ integration/mock-service/.uptodate:
 lint: ## Run golangci-lint
 	golangci-lint run --timeout=5m
 
+.PHONY: fix-lint
+fix-lint: ## Automatically fix linting issues where possible
+	golangci-lint run --timeout=5m --fix
+
 .PHONY: clean
 clean: ## Run go clean and remove the rollout-operator binary
 	rm -f rollout-operator

cmd/rollout-operator/main.go

@@ -23,15 +23,15 @@ import (
 	"go.uber.org/atomic"
 	v1 "k8s.io/api/admission/v1"
 	"k8s.io/client-go/kubernetes"
+	// Required to get the GCP auth provider working.
+	_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/clientcmd"
 
 	"github.com/grafana/rollout-operator/pkg/admission"
 	"github.com/grafana/rollout-operator/pkg/controller"
 	"github.com/grafana/rollout-operator/pkg/instrumentation"
 	"github.com/grafana/rollout-operator/pkg/tlscert"
-	// Required to get the GCP auth provider working.
-	_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
 )
 
 const defaultServerSelfSignedCertExpiration = model.Duration(365 * 24 * time.Hour)

pkg/admission/zone_tracker.go

@@ -11,14 +11,14 @@ import (
 	"github.com/go-kit/log/level"
 	"github.com/grafana/dskit/spanlogger"
 	"github.com/opentracing/opentracing-go"
-	k8serrors "k8s.io/apimachinery/pkg/api/errors"
-	"k8s.io/client-go/kubernetes"
-
-	"github.com/grafana/rollout-operator/pkg/config"
 	v1 "k8s.io/api/admission/v1"
 	appsv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
+	k8serrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+
+	"github.com/grafana/rollout-operator/pkg/config"
 )
 
 type zoneTracker struct {

pkg/admission/zone_tracker_test.go

@@ -7,12 +7,13 @@ import (
 	"testing"
 	"time"
 
-	"github.com/grafana/rollout-operator/pkg/config"
 	apps "k8s.io/api/apps/v1"
 	appsv1 "k8s.io/api/apps/v1"
 	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes/fake"
+
+	"github.com/grafana/rollout-operator/pkg/config"
 )
 
 func TestZoneTracker(t *testing.T) {