3 files changed, 255 insertions, 0 deletions
diff --git a/tools/issue_reviver/github/BUILD b/tools/issue_reviver/github/BUILD
new file mode 100644
index 000000000..0eabc2835
--- /dev/null
+++ b/tools/issue_reviver/github/BUILD
@@ -0,0 +1,24 @@
+load("//tools:defs.bzl", "go_library", "go_test")
+
+package(licenses = ["notice"])
+
+go_library(
+    name = "github",
+    srcs = ["github.go"],
+    nogo = False,
+    visibility = [
+        "//tools/issue_reviver:__subpackages__",
+    ],
+    deps = [
+        "//tools/issue_reviver/reviver",
+        "@com_github_google_go_github_v28//github:go_default_library",
+        "@org_golang_x_oauth2//:go_default_library",
+    ],
+)
+
+go_test(
+    name = "github_test",
+    size = "small",
+    srcs = ["github_test.go"],
+    library = ":github",
+)
diff --git a/tools/issue_reviver/github/github.go b/tools/issue_reviver/github/github.go
new file mode 100644
index 000000000..8ffd7e606
--- /dev/null
+++ b/tools/issue_reviver/github/github.go
@@ -0,0 +1,176 @@
+// Copyright 2019 The gVisor 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 github implements reviver.Bugger interface on top of Github issues.
+package github
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/google/go-github/github"
+	"golang.org/x/oauth2"
+	"gvisor.dev/gvisor/tools/issue_reviver/reviver"
+)
+
+// Bugger implements reviver.Bugger interface for github issues.
+type Bugger struct {
+	owner  string
+	repo   string
+	dryRun bool
+
+	client *github.Client
+	issues map[int]*github.Issue
+}
+
+// NewBugger creates a new Bugger.
+func NewBugger(token, owner, repo string, dryRun bool) (*Bugger, error) {
+	b := &Bugger{
+		owner:  owner,
+		repo:   repo,
+		dryRun: dryRun,
+		issues: map[int]*github.Issue{},
+	}
+	if err := b.load(token); err != nil {
+		return nil, err
+	}
+	return b, nil
+}
+
+func (b *Bugger) load(token string) error {
+	ctx := context.Background()
+	if len(token) == 0 {
+		fmt.Print("No OAUTH token provided, using unauthenticated account.\n")
+		b.client = github.NewClient(nil)
+	} else {
+		ts := oauth2.StaticTokenSource(
+			&oauth2.Token{AccessToken: token},
+		)
+		tc := oauth2.NewClient(ctx, ts)
+		b.client = github.NewClient(tc)
+	}
+
+	err := processAllPages(func(listOpts github.ListOptions) (*github.Response, error) {
+		opts := &github.IssueListByRepoOptions{State: "open", ListOptions: listOpts}
+		tmps, resp, err := b.client.Issues.ListByRepo(ctx, b.owner, b.repo, opts)
+		if err != nil {
+			return resp, err
+		}
+		for _, issue := range tmps {
+			b.issues[issue.GetNumber()] = issue
+		}
+		return resp, nil
+	})
+	if err != nil {
+		return err
+	}
+
+	fmt.Printf("Loaded %d issues from github.com/%s/%s\n", len(b.issues), b.owner, b.repo)
+	return nil
+}
+
+// Activate implements reviver.Bugger.
+func (b *Bugger) Activate(todo *reviver.Todo) (bool, error) {
+	id, err := parseIssueNo(todo.Issue)
+	if err != nil {
+		return true, err
+	}
+	if id <= 0 {
+		return false, nil
+	}
+
+	// Check against active issues cache.
+	if _, ok := b.issues[id]; ok {
+		fmt.Printf("%q is active: OK\n", todo.Issue)
+		return true, nil
+	}
+
+	fmt.Printf("%q is not active: reopening issue %d\n", todo.Issue, id)
+
+	// Format comment with TODO locations and search link.
+	comment := strings.Builder{}
+	fmt.Fprintln(&comment, "There are TODOs still referencing this issue:")
+	for _, l := range todo.Locations {
+		fmt.Fprintf(&comment,
+			"1. [%s:%d](https://github.com/%s/%s/blob/HEAD/%s#%d): %s\n",
+			l.File, l.Line, b.owner, b.repo, l.File, l.Line, l.Comment)
+	}
+	fmt.Fprintf(&comment,
+		"\n\nSearch [TODO](https://github.com/%s/%s/search?q=%%22%s%%22)", b.owner, b.repo, todo.Issue)
+
+	if b.dryRun {
+		fmt.Printf("[dry-run: skipping change to issue %d]\n%s\n=======================\n", id, comment.String())
+		return true, nil
+	}
+
+	ctx := context.Background()
+	req := &github.IssueRequest{State: github.String("open")}
+	_, _, err = b.client.Issues.Edit(ctx, b.owner, b.repo, id, req)
+	if err != nil {
+		return true, fmt.Errorf("failed to reactivate issue %d: %v", id, err)
+	}
+
+	cmt := &github.IssueComment{
+		Body:      github.String(comment.String()),
+		Reactions: &github.Reactions{Confused: github.Int(1)},
+	}
+	if _, _, err := b.client.Issues.CreateComment(ctx, b.owner, b.repo, id, cmt); err != nil {
+		return true, fmt.Errorf("failed to add comment to issue %d: %v", id, err)
+	}
+
+	return true, nil
+}
+
+// parseIssueNo parses the issue number out of the issue url.
+func parseIssueNo(url string) (int, error) {
+	const prefix = "gvisor.dev/issue/"
+
+	// First check if I can handle the TODO.
+	idStr := strings.TrimPrefix(url, prefix)
+	if len(url) == len(idStr) {
+		return 0, nil
+	}
+
+	id, err := strconv.ParseInt(strings.TrimRight(idStr, "/"), 10, 64)
+	if err != nil {
+		return 0, err
+	}
+	return int(id), nil
+}
+
+func processAllPages(fn func(github.ListOptions) (*github.Response, error)) error {
+	opts := github.ListOptions{PerPage: 1000}
+	for {
+		resp, err := fn(opts)
+		if err != nil {
+			if rateErr, ok := err.(*github.RateLimitError); ok {
+				duration := rateErr.Rate.Reset.Sub(time.Now())
+				if duration > 5*time.Minute {
+					return fmt.Errorf("Rate limited for too long: %v", duration)
+				}
+				fmt.Printf("Rate limited, sleeping for: %v\n", duration)
+				time.Sleep(duration)
+				continue
+			}
+			return err
+		}
+		if resp.NextPage == 0 {
+			return nil
+		}
+		opts.Page = resp.NextPage
+	}
+}
diff --git a/tools/issue_reviver/github/github_test.go b/tools/issue_reviver/github/github_test.go
new file mode 100644
index 000000000..a78b230ef
--- /dev/null
+++ b/tools/issue_reviver/github/github_test.go
@@ -0,0 +1,55 @@
+// Copyright 2020 The gVisor 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 github
+
+import (
+	"testing"
+)
+
+func TestParseIssueNo(t *testing.T) {
+	testCases := []struct {
+		issue     string
+		expectErr bool
+		expected  int
+	}{
+		{
+			issue:    "gvisor.dev/issue/123",
+			expected: 123,
+		},
+		{
+			issue:    "gvisor.dev/issue/123/",
+			expected: 123,
+		},
+		{
+			issue:    "not a url",
+			expected: 0,
+		},
+		{
+			issue:     "gvisor.dev/issue//",
+			expectErr: true,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.issue, func(t *testing.T) {
+			id, err := parseIssueNo(tc.issue)
+			if err != nil && !tc.expectErr {
+				t.Errorf("got error: %v", err)
+			} else if tc.expected != id {
+				t.Errorf("got: %v, want: %v", id, tc.expected)
+			}
+		})
+	}
+}