gcc/libgo/go/golang.org/x/mod/sumdb/test.go

125 lines
2.8 KiB
Go

// Copyright 2019 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 sumdb
import (
"context"
"fmt"
"sync"
"golang.org/x/mod/module"
"golang.org/x/mod/sumdb/note"
"golang.org/x/mod/sumdb/tlog"
)
// NewTestServer constructs a new TestServer
// that will sign its tree with the given signer key
// (see golang.org/x/mod/sumdb/note)
// and fetch new records as needed by calling gosum.
func NewTestServer(signer string, gosum func(path, vers string) ([]byte, error)) *TestServer {
return &TestServer{signer: signer, gosum: gosum}
}
// A TestServer is an in-memory implementation of Server for testing.
type TestServer struct {
signer string
gosum func(path, vers string) ([]byte, error)
mu sync.Mutex
hashes testHashes
records [][]byte
lookup map[string]int64
}
// testHashes implements tlog.HashReader, reading from a slice.
type testHashes []tlog.Hash
func (h testHashes) ReadHashes(indexes []int64) ([]tlog.Hash, error) {
var list []tlog.Hash
for _, id := range indexes {
list = append(list, h[id])
}
return list, nil
}
func (s *TestServer) Signed(ctx context.Context) ([]byte, error) {
s.mu.Lock()
defer s.mu.Unlock()
size := int64(len(s.records))
h, err := tlog.TreeHash(size, s.hashes)
if err != nil {
return nil, err
}
text := tlog.FormatTree(tlog.Tree{N: size, Hash: h})
signer, err := note.NewSigner(s.signer)
if err != nil {
return nil, err
}
return note.Sign(&note.Note{Text: string(text)}, signer)
}
func (s *TestServer) ReadRecords(ctx context.Context, id, n int64) ([][]byte, error) {
s.mu.Lock()
defer s.mu.Unlock()
var list [][]byte
for i := int64(0); i < n; i++ {
if id+i >= int64(len(s.records)) {
return nil, fmt.Errorf("missing records")
}
list = append(list, s.records[id+i])
}
return list, nil
}
func (s *TestServer) Lookup(ctx context.Context, m module.Version) (int64, error) {
key := m.String()
s.mu.Lock()
id, ok := s.lookup[key]
s.mu.Unlock()
if ok {
return id, nil
}
// Look up module and compute go.sum lines.
data, err := s.gosum(m.Path, m.Version)
if err != nil {
return 0, err
}
s.mu.Lock()
defer s.mu.Unlock()
// We ran the fetch without the lock.
// If another fetch happened and committed, use it instead.
id, ok = s.lookup[key]
if ok {
return id, nil
}
// Add record.
id = int64(len(s.records))
s.records = append(s.records, data)
if s.lookup == nil {
s.lookup = make(map[string]int64)
}
s.lookup[key] = id
hashes, err := tlog.StoredHashesForRecordHash(id, tlog.RecordHash([]byte(data)), s.hashes)
if err != nil {
panic(err)
}
s.hashes = append(s.hashes, hashes...)
return id, nil
}
func (s *TestServer) ReadTileData(ctx context.Context, t tlog.Tile) ([]byte, error) {
s.mu.Lock()
defer s.mu.Unlock()
return tlog.ReadTileData(t, s.hashes)
}