Logger Linter

main.go

package main

import (
	"fmt"
	"go/ast"
	"golang.org/x/tools/go/analysis"
	"golang.org/x/tools/go/analysis/singlechecker"
)

var Analyzer = &analysis.Analyzer{
	Name: "checklogger",
	Doc:  "Verifies that the logger has the proper function name declared",
	Run:  run,
}

func run(pass *analysis.Pass) (interface{}, error) {
	for _, file := range pass.Files {
		ast.Inspect(file, func(fileNode ast.Node) bool {
			if funcDecl, ok := fileNode.(*ast.FuncDecl); ok {
				ast.Inspect(funcDecl.Body, func(bodyNode ast.Node) bool {
					if localLog, ok := bodyNode.(*ast.AssignStmt); ok && isLocalLog(localLog) {
						var found = false
						ast.Inspect(localLog, func(logNode ast.Node) bool {
							if selectorExpr, ok := logNode.(*ast.SelectorExpr); ok && selectorExpr.Sel.Name == "Str" {
								if callExpr, ok := selectorExpr.X.(*ast.CallExpr); ok && len(callExpr.Args) == 2 {
									if var1, ok := callExpr.Args[0].(*ast.BasicLit); ok && var1.Value == "\"function\"" {
										found = true
										functionValue := callExpr.Args[1].(*ast.BasicLit).Value
										if functionValue != fmt.Sprintf("\"%s\"", funcDecl.Name.Name) {
											pass.Reportf(callExpr.Args[1].Pos(), "Function is mislabeled and should be \"%s\"", funcDecl.Name.Name)
										}
									}
								}
							}
							return true
						})

						if !found {
							pass.Reportf(localLog.Pos(), "Logger is missing 'function' field declaration")
						}
					}
					return true
				})
			}
			return true
		})

	}

	return nil, nil
}

func isLocalLog(n *ast.AssignStmt) bool {
	for _, expr := range n.Lhs {
		if value, ok := expr.(*ast.Ident); ok && value.Name == "localLog" {
			return true
		}
	}
	return false
}

func main() {
	singlechecker.Main(Analyzer)
}