Initialize module and dependencies

vendor/golang.org/x/vuln/internal/client/index.go

@@ -0,0 +1,120 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package client
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/fs"
+	"os"
+	"path/filepath"
+
+	"golang.org/x/vuln/internal/osv"
+	isem "golang.org/x/vuln/internal/semver"
+)
+
+// indexFromDir returns a raw index created from a directory
+// containing OSV entries.
+// It skips any non-JSON files but errors if any of the JSON files
+// cannot be unmarshaled into OSV, or have a filename other than <ID>.json.
+func indexFromDir(dir string) (map[string][]byte, error) {
+	idx := newIndex()
+	f := os.DirFS(dir)
+
+	if err := filepath.WalkDir(dir, func(path string, d fs.DirEntry, err error) error {
+		fname := d.Name()
+		ext := filepath.Ext(fname)
+		switch {
+		case err != nil:
+			return err
+		case d.IsDir():
+			return nil
+		case ext != ".json":
+			return nil
+		}
+
+		b, err := fs.ReadFile(f, d.Name())
+		if err != nil {
+			return err
+		}
+		var entry osv.Entry
+		if err := json.Unmarshal(b, &entry); err != nil {
+			return err
+		}
+		if fname != entry.ID+".json" {
+			return fmt.Errorf("OSV entries must have filename of the form <ID>.json, got %s", fname)
+		}
+
+		idx.add(&entry)
+		return nil
+	}); err != nil {
+		return nil, err
+	}
+
+	return idx.raw()
+}
+
+func indexFromEntries(entries []*osv.Entry) (map[string][]byte, error) {
+	idx := newIndex()
+
+	for _, entry := range entries {
+		idx.add(entry)
+	}
+
+	return idx.raw()
+}
+
+type index struct {
+	db      *dbMeta
+	modules modulesIndex
+}
+
+func newIndex() *index {
+	return &index{
+		db:      &dbMeta{},
+		modules: make(map[string]*moduleMeta),
+	}
+}
+
+func (i *index) add(entry *osv.Entry) {
+	// Add to db index.
+	if entry.Modified.After(i.db.Modified) {
+		i.db.Modified = entry.Modified
+	}
+	// Add to modules index.
+	for _, affected := range entry.Affected {
+		modulePath := affected.Module.Path
+		if _, ok := i.modules[modulePath]; !ok {
+			i.modules[modulePath] = &moduleMeta{
+				Path:  modulePath,
+				Vulns: []moduleVuln{},
+			}
+		}
+		module := i.modules[modulePath]
+		module.Vulns = append(module.Vulns, moduleVuln{
+			ID:       entry.ID,
+			Modified: entry.Modified,
+			Fixed:    isem.NonSupersededFix(affected.Ranges),
+		})
+	}
+}
+
+func (i *index) raw() (map[string][]byte, error) {
+	data := make(map[string][]byte)
+
+	b, err := json.Marshal(i.db)
+	if err != nil {
+		return nil, err
+	}
+	data[dbEndpoint] = b
+
+	b, err = json.Marshal(i.modules)
+	if err != nil {
+		return nil, err
+	}
+	data[modulesEndpoint] = b
+
+	return data, nil
+}