blob: cba8b4fd81c17862ba07ead8a2d9c8710f74616a [file] [log] [blame]
// 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 index provides a client for communicating with the module index.
package index
import (
// A Client is used by the worker service to communicate with the module index.
type Client struct {
// URL of the module index
url string
// client used for HTTP requests. It is mutable for testing purposes.
httpClient *http.Client
// New constructs a *Client using the provided rawurl, which is expected to
// be an absolute URI that can be directly passed to http.Get.
func New(rawurl string) (_ *Client, err error) {
defer derrors.Add(&err, "index.New(%q)", rawurl)
u, err := url.Parse(rawurl)
if err != nil {
return nil, fmt.Errorf("url.Parse(%q): %v", rawurl, err)
if u.Scheme != "https" {
return nil, fmt.Errorf("scheme must be https (got %s)", u.Scheme)
return &Client{url: strings.TrimRight(rawurl, "/"), httpClient: &http.Client{Transport: &ochttp.Transport{}}}, nil
func (c *Client) pollURL(since time.Time, limit int) string {
values := url.Values{}
values.Set("since", since.Format(time.RFC3339))
if limit > 0 {
values.Set("limit", strconv.Itoa(limit))
return fmt.Sprintf("%s?%s", c.url, values.Encode())
// GetVersions queries the index for new versions.
func (c *Client) GetVersions(ctx context.Context, since time.Time, limit int) (_ []*internal.IndexVersion, err error) {
defer derrors.Wrap(&err, "index.Client.GetVersions(ctx, %s, %d)", since, limit)
u := c.pollURL(since, limit)
r, err := ctxhttp.Get(ctx, c.httpClient, u)
if err != nil {
return nil, fmt.Errorf("ctxhttp.Get(ctx, nil, %q): %v", u, err)
defer r.Body.Close()
var versions []*internal.IndexVersion
dec := json.NewDecoder(r.Body)
// The module index returns a stream of JSON objects formatted with newline
// as the delimiter.
for dec.More() {
var l internal.IndexVersion
if err := dec.Decode(&l); err != nil {
return nil, fmt.Errorf("decoding JSON: %v", err)
versions = append(versions, &l)
return versions, nil