Adding staticcheck to the CI

This commit adds static check to our CI and fixes all of its complaints.

Author: ricardomaraschini

.github/workflows/pullrequest.yaml

@@ -27,6 +27,21 @@ jobs:
     - name: run linter
       run: golint -set_exit_status ./cmd/kubectl-image ./cmd/imgctrl ./controllers/... ./services/...
 
+  staticcheck:
+    name: staticcheck
+    runs-on: ubuntu-latest
+    container:
+      image: quay.io/tagger/actions-image:latest
+    steps:
+    - name: check out code
+      uses: actions/checkout@v2
+      with:
+        repository: ${{ github.event.pull_request.head.repo.full_name }}
+        ref: ${{ github.event.pull_request.head.ref }}
+
+    - name: run staticcheck
+      run: staticcheck ./...
+
   unit:
     name: unit
     runs-on: ubuntu-latest
@@ -47,6 +62,7 @@ jobs:
     needs:
       - lint
       - unit
+      - staticcheck
     runs-on: ubuntu-latest
     container:
       image: quay.io/tagger/actions-image:latest
@@ -65,6 +81,7 @@ jobs:
     needs:
       - lint
       - unit
+      - staticcheck
     runs-on: ubuntu-latest
     steps:
     - name: check out code

infra/images/v1beta1/types.go

@@ -151,14 +151,14 @@ func (t *ImageImport) FlaggedAsConsumedDuration() (time.Duration, error) {
 	}
 
 	strsince := t.Annotations[ImageImportConsumedFlagAnnotation]
-	since, err := time.Parse(time.ANSIC, strsince)
+	flagtime, err := time.Parse(time.ANSIC, strsince)
 	if err != nil {
 		return 0, fmt.Errorf(
 			"bogus %s annotation: %w", ImageImportConsumedFlagAnnotation, err,
 		)
 	}
 
-	return time.Now().Sub(since), nil
+	return time.Since(flagtime), nil
 }
 
 // CurrentReferenceForImage looks through provided Image  and returns the most recent imported

services/imageimport.go

@@ -301,7 +301,7 @@ func (t *ImageImport) Import(
 				return nil, fmt.Errorf("fail to mirror image: %w", err)
 			}
 
-			latency := time.Now().Sub(start).Seconds()
+			latency := time.Since(start).Seconds()
 			metrics.MirrorLatency.Observe(latency)
 		}
 

services/imageio.go

@@ -70,7 +70,7 @@ func (t *ImageIO) Push(ctx context.Context, ns, name string, fpath string) error
 			metrics.PushFailures.Inc()
 			return
 		}
-		latency := time.Now().Sub(start).Seconds()
+		latency := time.Since(start).Seconds()
 		metrics.PushLatency.Observe(latency)
 		metrics.PushSuccesses.Inc()
 	}()
@@ -126,7 +126,7 @@ func (t *ImageIO) Pull(ctx context.Context, ns, name string) (*os.File, func(),
 			return
 		}
 
-		latency := time.Now().Sub(start).Seconds()
+		latency := time.Since(start).Seconds()
 		metrics.PullLatency.Observe(latency)
 		metrics.PullSuccesses.Inc()
 	}()