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

tools/mattermost-govet/configtelemetry/telemetry.go

@@ -0,0 +1,129 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package configtelemetry
+
+import (
+	"errors"
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/types"
+	"reflect"
+	"strings"
+
+	"github.com/mattermost/mattermost/tools/mattermost-govet/util"
+	"golang.org/x/tools/go/analysis"
+)
+
+var (
+	telemetryPkgPath = util.ServerModulePath + "/platform/telemetry"
+	modelPkgPath     = util.ModelPkgPath
+)
+
+const (
+	configStructName = "Config"
+	telemetryPkgName = "telemetry"
+)
+
+// Analyzer reports config fields where telemetry is not sent
+var Analyzer = &analysis.Analyzer{
+	Name:       "configtelemetry",
+	Doc:        "reports config fields where telemetry is not sent (unless it is specifically indicated  that no telemetry will be sent for that field)",
+	Run:        run,
+	ResultType: reflect.TypeOf(&analysis.Pass{}),
+}
+
+func run(pass *analysis.Pass) (interface{}, error) {
+	if pass.Pkg.Path() != telemetryPkgPath {
+		return pass, nil
+	}
+
+	// we need to find model.Config definition to parse its Type Spec
+	var configObject *types.TypeName
+	for _, obj := range pass.TypesInfo.Uses {
+		if tn, ok := obj.(*types.TypeName); ok && obj.Name() == configStructName && obj.Pkg().Path() == modelPkgPath {
+			configObject = tn
+			break
+		}
+	}
+
+	if configObject == nil {
+		return pass, errors.New("could not find model.Config type")
+	}
+
+	if !configObject.Pos().IsValid() {
+		return pass, errors.New("model.Config position is not valid")
+	}
+
+	srcFile := pass.Fset.PositionFor(configObject.Pos(), false).Filename
+	file, err := parser.ParseFile(pass.Fset, srcFile, nil, parser.AllErrors|parser.ParseComments)
+	if err != nil {
+		return pass, fmt.Errorf("could parse file %q: %w", srcFile, err)
+	}
+
+	pass.Files = append(pass.Files, file)
+
+	configMap, err := typeFieldMap(file, configObject.Name())
+	if err != nil {
+		return pass, fmt.Errorf("could generate fields map: %w", err)
+	}
+
+	var allExpressions []string
+
+	// We look at every expression in the file so that we can
+	// check if the expected references exist in this package.
+
+	// NOTE: this approach does not check if the reference (config field) is added
+	// to telemetry queue, it assumes that if a config field is used in the file,
+	// it probably added to the telemetry. This is a naive approach but should work.
+	// Also, we can narrow down this for specific function calls, declarations etc.
+	// so that we can be sure if the config field is added to telemetry but all these
+	// fine tuning will require extra maintenance cost and yet, it is still possible to
+	// trick the checker. Hence, it is decided to go with this broader check. This check
+	// can be considered as a reminder to developers when they forget to add a field to
+	// telemetry. Fortunately, further verification can be done at code reviews.
+	for _, file := range pass.Files {
+		if file.Name.Name != telemetryPkgName {
+			continue
+		}
+
+		ast.Inspect(file, func(n ast.Node) bool {
+			expr, ok := n.(ast.Expr)
+			if !ok {
+				return true
+			}
+
+			sel, ok := expr.(*ast.SelectorExpr)
+			if !ok {
+				return true
+			}
+
+			allExpressions = append(allExpressions, getFieldAccessSequence(sel))
+			return true
+		})
+	}
+
+	// now remove the expresions from what's expected
+	for _, ref := range allExpressions {
+		delete(configMap, ref)
+	}
+
+	// report remaining fields from the map
+	for k, v := range configMap {
+		pass.Reportf(v, "%v is not used in telemetry", k)
+	}
+
+	return pass, nil
+}
+
+// getFieldAccessSequence is used recursively to get string representation of
+// a selector expression sequence. e.g. config.ServiceSettings.SiteURL
+func getFieldAccessSequence(sel *ast.SelectorExpr) string {
+	switch v := sel.X.(type) {
+	case *ast.SelectorExpr:
+		return strings.Join([]string{getFieldAccessSequence(v), sel.Sel.Name}, ".")
+	default:
+		return sel.Sel.Name
+	}
+}