Add a plugin for /pony

prow/plugins/BUILD.bazel

@@ -72,6 +72,7 @@ filegroup(
         "//prow/plugins/milestonestatus:all-srcs",
         "//prow/plugins/override:all-srcs",
         "//prow/plugins/owners-label:all-srcs",
+        "//prow/plugins/pony:all-srcs",
         "//prow/plugins/releasenote:all-srcs",
         "//prow/plugins/require-matching-label:all-srcs",
         "//prow/plugins/requiresig:all-srcs",

prow/plugins/pony/BUILD.bazel

@@ -0,0 +1,39 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["pony.go"],
+    importpath = "k8s.io/test-infra/prow/plugins/pony",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//prow/github:go_default_library",
+        "//prow/pluginhelp:go_default_library",
+        "//prow/plugins:go_default_library",
+        "//vendor/github.com/sirupsen/logrus:go_default_library",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["pony_test.go"],
+    embed = [":go_default_library"],
+    deps = [
+        "//prow/github:go_default_library",
+        "//prow/github/fakegithub:go_default_library",
+        "//vendor/github.com/sirupsen/logrus:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

prow/plugins/pony/pony.go

@@ -0,0 +1,163 @@
+/*
+Copyright 2018 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 pony adds pony images to issues in response to a /pony comment
+package pony
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+
+	"github.com/sirupsen/logrus"
+	"k8s.io/test-infra/prow/github"
+	"k8s.io/test-infra/prow/pluginhelp"
+	"k8s.io/test-infra/prow/plugins"
+)
+
+// Only the properties we actually use.
+type ponyResult struct {
+	Pony ponyResultPony `json:"pony"`
+}
+
+type ponyResultPony struct {
+	Representations ponyRepresentations `json:"representations"`
+}
+
+type ponyRepresentations struct {
+	Full  string `json:"full"`
+	Small string `json:"small"`
+}
+
+const (
+	ponyURL    = realHerd("https://theponyapi.com/pony.json")
+	pluginName = "pony"
+)
+
+var (
+	match = regexp.MustCompile(`(?mi)^/(?:pony)(?:\s+(.+?))?\s*$`)
+)
+
+func init() {
+	plugins.RegisterGenericCommentHandler(pluginName, handleGenericComment, helpProvider)
+}
+
+func helpProvider(config *plugins.Configuration, enabledRepos []string) (*pluginhelp.PluginHelp, error) {
+	// The Config field is omitted because this plugin is not configurable.
+	pluginHelp := &pluginhelp.PluginHelp{
+		Description: "The pony plugin adds a pony image to an issue in response to the `/pony` command.",
+	}
+	pluginHelp.AddCommand(pluginhelp.Command{
+		Usage:       "/(pony) [pony]",
+		Description: "Add a little pony image to the issue. A particular pony can optionally be named for a picture of that specific pony.",
+		Featured:    false,
+		WhoCanUse:   "Anyone",
+		Examples:    []string{"/pony", "/pony Twilight Sparkle"},
+	})
+	return pluginHelp, nil
+}
+
+var client = http.Client{}
+
+type githubClient interface {
+	CreateComment(owner, repo string, number int, comment string) error
+}
+
+type herd interface {
+	readPony(string) (string, error)
+}
+
+type realHerd string
+
+func formatURLs(small, full string) string {
+	return fmt.Sprintf("[![pony image](%s)](%s)", small, full)
+}
+
+func (h realHerd) readPony(tags string) (string, error) {
+	// Omit webm video (the only video type) and anything too far off square.
+	q := "-webm, aspect_ratio:1~0.5"
+	if tags != "" {
+		q += ", " + tags
+	}
+	uri := string(h) + "?q=" + url.QueryEscape(q)
+	resp, err := client.Get(uri)
+	if err != nil {
+		return "", fmt.Errorf("failed to make request: %v", err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		return "", fmt.Errorf("no pony found")
+	}
+	var a ponyResult
+	if err = json.NewDecoder(resp.Body).Decode(&a); err != nil {
+		return "", fmt.Errorf("failed to decode response: %v", err)
+	}
+
+	embedded := a.Pony.Representations.Small
+	tooBig, err := github.ImageTooBig(embedded)
+	if err != nil {
+		return "", fmt.Errorf("couldn't fetch pony for size check: %v", err)
+	}
+	if tooBig {
+		return "", fmt.Errorf("the pony is too big")
+	}
+	return formatURLs(a.Pony.Representations.Small, a.Pony.Representations.Full), nil
+}
+
+func handleGenericComment(pc plugins.Agent, e github.GenericCommentEvent) error {
+	return handle(pc.GitHubClient, pc.Logger, &e, ponyURL)
+}
+
+func handle(gc githubClient, log *logrus.Entry, e *github.GenericCommentEvent, p herd) error {
+	// Only consider new comments.
+	if e.Action != github.GenericCommentActionCreated {
+		return nil
+	}
+	// Make sure they are requesting a pony
+	mat := match.FindStringSubmatch(e.Body)
+	if mat == nil {
+		return nil
+	}
+
+	tag := mat[1]
+	org := e.Repo.Owner.Login
+	repo := e.Repo.Name
+	number := e.Number
+
+	for i := 0; i < 5; i++ {
+		resp, err := p.readPony(tag)
+		if err != nil {
+			log.WithError(err).Println("Failed to get a pony")
+			continue
+		}
+		return gc.CreateComment(org, repo, number, plugins.FormatResponseRaw(e.Body, e.HTMLURL, e.User.Login, resp))
+	}
+
+	var msg string
+	if tag != "" {
+		msg = "Couldn't find a pony matching that query."
+	} else {
+		msg = "https://theponyapi.com appears to be down"
+	}
+	if err := gc.CreateComment(org, repo, number, plugins.FormatResponseRaw(e.Body, e.HTMLURL, e.User.Login, msg)); err != nil {
+		log.WithError(err).Error("Failed to leave comment")
+	}
+
+	return errors.New("could not find a valid pony image")
+}