Migrate golangci-lint cfg to v2. Fix new findings

The new v2 version of `golangci-lint` comes with configuration file
structure and therefore the configuration had to be migrated.
I simply had to execute `golangci-lint migrate` and copy the comments to
the new config as they are not touched by the migration. There were also
few minor new findings that had to be fixed.

Author: chombium

.golangci.yml

@@ -1,4 +1,5 @@
 ---
+version: "2"
 run:
   # Timeout for analysis, e.g. 30s, 5m.
   # Default: 1m
@@ -12,16 +13,35 @@ linters:
     - gocyclo
     # Inspects source code for security problems.
     - gosec
-linters-settings:
-  gocyclo:
-    # Minimal code complexity to report.
-    # https://github.com/fzipp/gocyclo#readme
-    min-complexity: 28
-  gosec:
-    excludes:
-    - G115
+  settings:
+    gocyclo:
+      # Minimal code complexity to report.
+      # https://github.com/fzipp/gocyclo#readme
+      min-complexity: 28
+    gosec:
+      excludes:
+        # Ignore controversial integer overflow warnings.
+        - G115
+  exclusions:
+    generated: lax
+    presets:
+      - comments
+      - common-false-positives
+      - legacy
+      - std-error-handling
+    paths:
+      - third_party$
+      - builtin$
+      - examples$
 issues:
   # Disable max issues per linter.
   max-issues-per-linter: 0
   # Disable max same issues.
   max-same-issues: 0
+formatters:
+  exclusions:
+    generated: lax
+    paths:
+      - third_party$
+      - builtin$
+      - examples$

internal/command/meta.go

@@ -340,7 +340,7 @@ func getOptions(args []string, log Logger, mopts ...MetaOption) optionsFlags {
 		}
 	}
 
-	if opts.ShowGUID && !(_platform.Equal(opts.SourceType) || _all.Equal(opts.SourceType) || _default.Equal(opts.SourceType)) {
+	if opts.ShowGUID && !_platform.Equal(opts.SourceType) && !_all.Equal(opts.SourceType) && !_default.Equal(opts.SourceType) {
 		log.Fatalf("Source type must be 'platform' when using the --guid flag")
 	}
 

internal/command/query.go

@@ -132,15 +132,15 @@ func newQueryOptions(cli plugin.CliConnection, args []string, log Logger) (query
 	}
 
 	if len(args) != 1 {
-		return queryOptions{}, fmt.Errorf("Expected 1 argument, got %d.", len(args))
+		return queryOptions{}, fmt.Errorf("expected 1 argument, got %d", len(args))
 	}
 
 	if isInstantQuery(opts) && !validInstantQueryArgs(opts) {
-		return queryOptions{}, errors.New("When issuing an instant query, you cannot specify --start, --end, or --step")
+		return queryOptions{}, errors.New("when issuing an instant query, you cannot specify --start, --end, or --step")
 	}
 
 	if isRangeQuery(opts) && !validRangeQueryArgs(opts) {
-		return queryOptions{}, errors.New("When issuing a range query, you must specify all of --start, --end, and --step")
+		return queryOptions{}, errors.New("when issuing a range query, you must specify all of --start, --end, and --step")
 	}
 
 	if isInstantQuery(opts) {
@@ -150,7 +150,7 @@ func newQueryOptions(cli plugin.CliConnection, args []string, log Logger) (query
 
 		parsedTime, err := getParsedTime(opts.Time)
 		if err != nil {
-			return queryOptions{}, fmt.Errorf("Couldn't parse --time: %s", err.Error())
+			return queryOptions{}, fmt.Errorf("couldn't parse --time: %s", err.Error())
 		}
 
 		return queryOptions{timeProvided: true, time: parsedTime}, nil
@@ -159,11 +159,11 @@ func newQueryOptions(cli plugin.CliConnection, args []string, log Logger) (query
 	if isRangeQuery(opts) {
 		parsedStart, err := getParsedTime(opts.Start)
 		if err != nil {
-			return queryOptions{}, fmt.Errorf("Couldn't parse --start: %s", err.Error())
+			return queryOptions{}, fmt.Errorf("couldn't parse --start: %s", err.Error())
 		}
 		parsedEnd, err := getParsedTime(opts.End)
 		if err != nil {
-			return queryOptions{}, fmt.Errorf("Couldn't parse --end: %s", err.Error())
+			return queryOptions{}, fmt.Errorf("couldn't parse --end: %s", err.Error())
 		}
 
 		return queryOptions{start: parsedStart, end: parsedEnd, step: opts.Step, rangeQuery: true}, nil

internal/command/query_test.go

@@ -73,7 +73,7 @@ var _ = Describe("LogCache", func() {
 			}).To(Panic())
 
 			Expect(tc.logger.fatalfMessage).To(HavePrefix(
-				"When issuing a range query, you must specify all of --start, --end, and --step",
+				"when issuing a range query, you must specify all of --start, --end, and --step",
 			))
 		})
 
@@ -85,7 +85,7 @@ var _ = Describe("LogCache", func() {
 			}).To(Panic())
 
 			Expect(tc.logger.fatalfMessage).To(HavePrefix(
-				"When issuing an instant query, you cannot specify --start, --end, or --step",
+				"when issuing an instant query, you cannot specify --start, --end, or --step",
 			))
 		})
 
@@ -152,7 +152,7 @@ var _ = Describe("LogCache", func() {
 					}).To(Panic())
 
 					Expect(tc.logger.fatalfMessage).To(HavePrefix(
-						fmt.Sprintf("Couldn't parse --time: invalid time format: %s", timeArg),
+						fmt.Sprintf("couldn't parse --time: invalid time format: %s", timeArg),
 					))
 				},
 				Entry("with an arbitary string", "asdfkj"),
@@ -229,7 +229,7 @@ var _ = Describe("LogCache", func() {
 					}).To(Panic())
 
 					Expect(tc.logger.fatalfMessage).To(HavePrefix(
-						fmt.Sprintf("Couldn't parse --%s: invalid time format: %s", invalidField, invalidArg),
+						fmt.Sprintf("couldn't parse --%s: invalid time format: %s", invalidField, invalidArg),
 					))
 				},
 				Entry("with an arbitary string for start", "start", "asdfkj"),

internal/command/tail.go

@@ -238,11 +238,11 @@ func newTailOptions(cli plugin.CliConnection, args []string, log Logger) (tailOp
 	}
 
 	if len(args) != 1 {
-		return tailOptions{}, fmt.Errorf("Expected 1 argument, got %d.", len(args))
+		return tailOptions{}, fmt.Errorf("expected 1 argument, got %d", len(args))
 	}
 
 	if opts.JSONOutput && opts.OutputFormat != "" {
-		return tailOptions{}, errors.New("Cannot use output-format and json flags together")
+		return tailOptions{}, errors.New("cannot use output-format and json flags together")
 	}
 
 	if opts.EnvelopeType != "" && opts.EnvelopeClass != "" {
@@ -331,16 +331,16 @@ func typeFilter(e *loggregator_v2.Envelope, o tailOptions) bool {
 
 func (o tailOptions) validate() error {
 	if o.startTime.After(o.endTime) && o.endTime != time.Unix(0, 0) {
-		return errors.New("Invalid date/time range. Ensure your start time is prior or equal the end time.")
+		return errors.New("invalid date/time range. Ensure your start time is prior or equal the end time")
 	}
 
 	if o.lines > 1000 || o.lines < 0 {
-		return errors.New("Lines cannot be greater than 1000.")
+		return errors.New("lines cannot be greater than 1000")
 	}
 
 	_, err := regexp.Compile(o.nameFilter)
 	if err != nil {
-		return fmt.Errorf("Invalid name filter '%s'. Ensure your name-filter is a valid regex.", o.nameFilter)
+		return fmt.Errorf("invalid name filter '%s'. Ensure your name-filter is a valid regex", o.nameFilter)
 	}
 
 	return nil

internal/command/tail_test.go

@@ -1102,7 +1102,7 @@ var _ = Describe("LogCache", func() {
 				)
 			}).To(Panic())
 
-			Expect(logger.fatalfMessage).To(Equal("Cannot use output-format and json flags together"))
+			Expect(logger.fatalfMessage).To(Equal("cannot use output-format and json flags together"))
 		})
 
 		It("fatally logs if an output-format is malformed", func() {
@@ -1158,7 +1158,7 @@ var _ = Describe("LogCache", func() {
 				)
 			}).To(Panic())
 
-			Expect(logger.fatalfMessage).To(Equal("Lines cannot be greater than 1000."))
+			Expect(logger.fatalfMessage).To(Equal("lines cannot be greater than 1000"))
 		})
 
 		It("accepts 0 for --lines", func() {
@@ -1245,7 +1245,7 @@ var _ = Describe("LogCache", func() {
 				)
 			}).To(Panic())
 
-			Expect(logger.fatalfMessage).To(Equal("Invalid date/time range. Ensure your start time is prior or equal the end time."))
+			Expect(logger.fatalfMessage).To(Equal("invalid date/time range. Ensure your start time is prior or equal the end time"))
 		})
 
 		It("fatally logs if the name-filter regex is invalid", func() {
@@ -1261,7 +1261,7 @@ var _ = Describe("LogCache", func() {
 				)
 			}).To(Panic())
 
-			Expect(logger.fatalfMessage).To(Equal("Invalid name filter '*foo'. Ensure your name-filter is a valid regex."))
+			Expect(logger.fatalfMessage).To(Equal("invalid name filter '*foo'. Ensure your name-filter is a valid regex"))
 		})
 
 		It("fatally logs if too many arguments are given", func() {
@@ -1276,7 +1276,7 @@ var _ = Describe("LogCache", func() {
 				)
 			}).To(Panic())
 
-			Expect(logger.fatalfMessage).To(Equal("Expected 1 argument, got 2."))
+			Expect(logger.fatalfMessage).To(Equal("expected 1 argument, got 2"))
 		})
 
 		It("fatally logs if not enough arguments are given", func() {
@@ -1291,7 +1291,7 @@ var _ = Describe("LogCache", func() {
 				)
 			}).To(Panic())
 
-			Expect(logger.fatalfMessage).To(Equal("Expected 1 argument, got 0."))
+			Expect(logger.fatalfMessage).To(Equal("expected 1 argument, got 0"))
 		})
 
 		Context("when name-filter argument is not supplied", func() {