snapshot of https://github.com/mattermost/mattermost.git (master, 2026-09-16; blobs > 131072B omitted)

tools/mattermost-govet/structuredLogging/structuredLogging.go

@@ -0,0 +1,66 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package structuredLogging
+
+import (
+	"go/ast"
+
+	"golang.org/x/tools/go/analysis"
+)
+
+var Analyzer = &analysis.Analyzer{
+	Name: "structuredLogging",
+	Doc:  "check invalid usage of logging",
+	Run:  run,
+}
+
+func run(pass *analysis.Pass) (interface{}, error) {
+	for _, file := range pass.Files {
+		ast.Inspect(file, func(node ast.Node) bool {
+			switch x := node.(type) {
+			case *ast.CallExpr:
+				fun, ok := x.Fun.(*ast.SelectorExpr)
+				if !ok {
+					return true
+				}
+
+				module, ok := fun.X.(*ast.Ident)
+				if !ok {
+					return true
+				}
+
+				if (fun.Sel.Name != "Debug" && fun.Sel.Name != "Info" && fun.Sel.Name != "Warn" && fun.Sel.Name != "Error" && fun.Sel.Name != "Critical") || module.Name != "mlog" {
+					return true
+				}
+
+				if len(x.Args) == 0 {
+					return true
+				}
+
+				firstArg, ok := x.Args[0].(*ast.CallExpr)
+				if !ok {
+					return true
+				}
+
+				firstArgFun, ok := firstArg.Fun.(*ast.SelectorExpr)
+				if !ok {
+					return true
+				}
+
+				firstArgModule, ok := firstArgFun.X.(*ast.Ident)
+				if !ok {
+					return true
+				}
+
+				if (firstArgFun.Sel.Name != "Sprintf" && firstArgFun.Sel.Name != "Sprint") || firstArgModule.Name != "fmt" {
+					return true
+				}
+
+				pass.Reportf(node.Pos(), "Using fmt inside mlog function, use structured logging instead (example: mlog.Debug(\"Log message\", mlog.String(\"data_name\", data))).")
+			}
+			return true
+		})
+	}
+	return nil, nil
+}

tools/mattermost-govet/structuredLogging/structuredLogging_test.go

@@ -0,0 +1,15 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package structuredLogging
+
+import (
+	"testing"
+
+	"golang.org/x/tools/go/analysis/analysistest"
+)
+
+func TestAll(t *testing.T) {
+	testdata := analysistest.TestData()
+	analysistest.Run(t, testdata, Analyzer, "a")
+}

tools/mattermost-govet/structuredLogging/testdata/src/a/a.go

@@ -0,0 +1,71 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package a
+
+import "fmt"
+
+type mlog struct{}
+
+func (m *mlog) Debug(msg string, fields ...interface{}) {}
+func (m *mlog) Info(msg string, fields ...interface{})  {}
+func (m *mlog) Warn(msg string, fields ...interface{})  {}
+func (m *mlog) Error(msg string, fields ...interface{}) {}
+func (m *mlog) Critical(msg string, fields ...interface{}) {}
+func (m *mlog) String(key, val string) interface{} { return nil }
+
+var Mlog = &mlog{}
+
+func validStructuredLogging() {
+	// Valid: using structured logging correctly
+	mlog := Mlog
+	mlog.Debug("User logged in", mlog.String("user_id", "123"))
+	mlog.Info("Server started", mlog.String("port", "8065"))
+	mlog.Warn("High memory usage", mlog.String("usage", "90%"))
+	mlog.Error("Database connection failed", mlog.String("error", "timeout"))
+	mlog.Critical("System failure", mlog.String("component", "auth"))
+
+	// Valid: simple string messages without formatting
+	mlog.Debug("Simple message")
+	mlog.Info("Another message")
+
+	// Valid: fmt outside of mlog calls
+	msg := fmt.Sprintf("User %s logged in", "john")
+	_ = msg
+}
+
+func invalidStructuredLogging() {
+	mlog := Mlog
+
+	// Invalid: using fmt.Sprintf inside mlog.Debug
+	mlog.Debug(fmt.Sprintf("User %s logged in", "john")) // want "Using fmt inside mlog function, use structured logging instead"
+
+	// Invalid: using fmt.Sprintf inside mlog.Info
+	mlog.Info(fmt.Sprintf("Server started on port %d", 8065)) // want "Using fmt inside mlog function, use structured logging instead"
+
+	// Invalid: using fmt.Sprintf inside mlog.Warn
+	mlog.Warn(fmt.Sprintf("Memory usage: %d%%", 90)) // want "Using fmt inside mlog function, use structured logging instead"
+
+	// Invalid: using fmt.Sprintf inside mlog.Error
+	mlog.Error(fmt.Sprintf("Failed to connect: %v", "timeout")) // want "Using fmt inside mlog function, use structured logging instead"
+
+	// Invalid: using fmt.Sprintf inside mlog.Critical
+	mlog.Critical(fmt.Sprintf("System failure in %s", "auth")) // want "Using fmt inside mlog function, use structured logging instead"
+
+	// Invalid: using fmt.Sprint inside mlog calls
+	mlog.Debug(fmt.Sprint("User logged in")) // want "Using fmt inside mlog function, use structured logging instead"
+	mlog.Info(fmt.Sprint("Server started")) // want "Using fmt inside mlog function, use structured logging instead"
+}
+
+func edgeCases() {
+	mlog := Mlog
+
+	// Valid: fmt.Sprintf in subsequent arguments (not first)
+	mlog.Debug("Message", mlog.String("key", fmt.Sprintf("value %d", 123)))
+
+	// Valid: different function names
+	mlog.Debug("Message")
+
+	// Valid: no arguments
+	mlog.Debug("")
+}