/* Copyright 2019 The Kubernetes Authors. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. */ package main import ( "fmt" "go/ast" "k8s.io/component-base/metrics" ) var metricsOptionStructuresNames = []string{ "KubeOpts", "CounterOpts", "GaugeOpts", "HistogramOpts", "SummaryOpts", "TimingHistogramOpts", } func findStableMetricDeclaration(tree ast.Node, metricsImportName string) ([]*ast.CallExpr, []error) { v := stableMetricFinder{ metricsImportName: metricsImportName, stableMetricsFunctionCalls: []*ast.CallExpr{}, errors: []error{}, } ast.Walk(&v, tree) return v.stableMetricsFunctionCalls, v.errors } // Implements visitor pattern for ast.Node that collects all stable metric expressions type stableMetricFinder struct { metricsImportName string currentFunctionCall *ast.CallExpr stableMetricsFunctionCalls []*ast.CallExpr errors []error } var _ ast.Visitor = (*stableMetricFinder)(nil) func contains(v metrics.StabilityLevel, a []metrics.StabilityLevel) bool { for _, i := range a { if i == v { return true } } return false } func (f *stableMetricFinder) Visit(node ast.Node) (w ast.Visitor) { switch opts := node.(type) { case *ast.CallExpr: if se, ok := opts.Fun.(*ast.SelectorExpr); ok { if se.Sel.Name == "NewDesc" { sl, _ := decodeStabilityLevel(opts.Args[4], f.metricsImportName) if sl != nil { classes := []metrics.StabilityLevel{metrics.STABLE, metrics.BETA} if ALL_STABILITY_CLASSES { classes = append(classes, metrics.ALPHA) } switch { case contains(*sl, classes): f.stableMetricsFunctionCalls = append(f.stableMetricsFunctionCalls, opts) f.currentFunctionCall = nil default: return nil } } } else { f.currentFunctionCall = opts } } else { f.currentFunctionCall = opts } case *ast.CompositeLit: se, ok := opts.Type.(*ast.SelectorExpr) if !ok { return f } if !isMetricOps(se.Sel.Name) { return f } id, ok := se.X.(*ast.Ident) if !ok { return f } if id.Name != f.metricsImportName { return f } stabilityLevel, err := getStabilityLevel(opts, f.metricsImportName) if err != nil { f.errors = append(f.errors, err) return nil } classes := []metrics.StabilityLevel{metrics.STABLE, metrics.BETA} if ALL_STABILITY_CLASSES { classes = append(classes, metrics.ALPHA) } switch { case contains(*stabilityLevel, classes): if f.currentFunctionCall == nil { f.errors = append(f.errors, newDecodeErrorf(opts, errNotDirectCall)) return nil } f.stableMetricsFunctionCalls = append(f.stableMetricsFunctionCalls, f.currentFunctionCall) f.currentFunctionCall = nil default: return nil } default: if f.currentFunctionCall == nil || node == nil || node.Pos() < f.currentFunctionCall.Rparen { return f } f.currentFunctionCall = nil } return f } func isMetricOps(name string) bool { var found = false for _, optsName := range metricsOptionStructuresNames { if name == optsName { found = true break } } return found } func getStabilityLevel(opts *ast.CompositeLit, metricsFrameworkImportName string) (*metrics.StabilityLevel, error) { for _, expr := range opts.Elts { kv, ok := expr.(*ast.KeyValueExpr) if !ok { return nil, newDecodeErrorf(expr, errPositionalArguments) } key := fmt.Sprintf("%v", kv.Key) if key != "StabilityLevel" { continue } return decodeStabilityLevel(kv.Value, metricsFrameworkImportName) } stability := metrics.ALPHA return &stability, nil }