access token is now optional

* fix some err checks
* github api url can be configured (e.g. point it at an enterprise instance)

[finishes #89638752 #89633744]

Signed-off-by: Chris Brown <cbrown@pivotal.io>

README.md

@@ -4,14 +4,17 @@ Fetches and creates versioned GitHub resources.
 
 ## Source Configuration
 
-* `access_token`: *Required.* The GitHub access token that should be used to
-  access the API.
-
 * `user`: *Required.* The GitHub username or organization name for the
   repository that the releases are in.
 
 * `repository`: *Required.* The repository name that contains the releases.
 
+* `access_token`: *Optional.* The GitHub access token that should be used to
+  access the API. Only required for publishing releases.
+
+* `github_api_url`: *Optional.* If you use a non-public GitHub deployment then
+  you can set your API URL here.
+
 ## Behavior
 
 ### `check`: Check for released versions.

cmd/check/check.go

@@ -11,7 +11,11 @@ func main() {
 	var request resource.CheckRequest
 	inputRequest(&request)
 
-	github := resource.NewGitHubClient(request.Source)
+	github, err := resource.NewGitHubClient(request.Source)
+	if err != nil {
+		resource.Fatal("constructing github client", err)
+	}
+
 	command := resource.NewCheckCommand(github)
 	response, err := command.Run(request)
 	if err != nil {

cmd/in/in.go

@@ -18,7 +18,11 @@ func main() {
 
 	destDir := os.Args[1]
 
-	github := resource.NewGitHubClient(request.Source)
+	github, err := resource.NewGitHubClient(request.Source)
+	if err != nil {
+		resource.Fatal("constructing github client", err)
+	}
+
 	command := resource.NewInCommand(github, os.Stderr)
 	response, err := command.Run(destDir, request)
 	if err != nil {

cmd/out/out.go

@@ -18,7 +18,11 @@ func main() {
 
 	sourceDir := os.Args[1]
 
-	github := resource.NewGitHubClient(request.Source)
+	github, err := resource.NewGitHubClient(request.Source)
+	if err != nil {
+		resource.Fatal("constructing github client", err)
+	}
+
 	command := resource.NewOutCommand(github, os.Stderr)
 	response, err := command.Run(sourceDir, request)
 	if err != nil {

github.go

@@ -2,6 +2,7 @@ package resource
 
 import (
 	"errors"
+	"net/url"
 	"os"
 
 	"code.google.com/p/goauth2/oauth"
@@ -28,20 +29,34 @@ type GitHubClient struct {
 	repository string
 }
 
-func NewGitHubClient(source Source) *GitHubClient {
+func NewGitHubClient(source Source) (*GitHubClient, error) {
 	transport := &oauth.Transport{
 		Token: &oauth.Token{
 			AccessToken: source.AccessToken,
 		},
 	}
 
-	client := github.NewClient(transport.Client())
+	var client *github.Client
+
+	if transport.Token.AccessToken == "" {
+		client = github.NewClient(nil)
+	} else {
+		client = github.NewClient(transport.Client())
+	}
+
+	if source.GitHubAPIURL != "" {
+		var err error
+		client.BaseURL, err = url.Parse(source.GitHubAPIURL)
+		if err != nil {
+			return nil, err
+		}
+	}
 
 	return &GitHubClient{
 		client:     client,
 		user:       source.User,
 		repository: source.Repository,
-	}
+	}, nil
 }
 
 func (g *GitHubClient) ListReleases() ([]github.RepositoryRelease, error) {

github_test.go

@@ -0,0 +1,79 @@
+package resource_test
+
+import (
+	"net/http"
+
+	. "github.com/concourse/github-release-resource"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/onsi/gomega/ghttp"
+)
+
+var _ = Describe("GitHub Client", func() {
+	var server *ghttp.Server
+	var client *GitHubClient
+	var source Source
+
+	BeforeEach(func() {
+		server = ghttp.NewServer()
+	})
+
+	JustBeforeEach(func() {
+		source.GitHubAPIURL = server.URL()
+
+		var err error
+		client, err = NewGitHubClient(source)
+		Ω(err).ShouldNot(HaveOccurred())
+	})
+
+	AfterEach(func() {
+		server.Close()
+	})
+
+	Context("with an OAuth Token", func() {
+		BeforeEach(func() {
+			source = Source{
+				User:        "concourse",
+				Repository:  "concourse",
+				AccessToken: "abc123",
+			}
+
+			server.AppendHandlers(
+				ghttp.CombineHandlers(
+					ghttp.VerifyRequest("GET", "/repos/concourse/concourse/releases"),
+					ghttp.RespondWith(200, "[]"),
+					ghttp.VerifyHeaderKV("Authorization", "Bearer abc123"),
+				),
+			)
+		})
+
+		It("sends one", func() {
+			_, err := client.ListReleases()
+			Ω(err).ShouldNot(HaveOccurred())
+		})
+	})
+
+	Context("without an OAuth Token", func() {
+		BeforeEach(func() {
+			source = Source{
+				User:       "concourse",
+				Repository: "concourse",
+			}
+
+			server.AppendHandlers(
+				ghttp.CombineHandlers(
+					ghttp.VerifyRequest("GET", "/repos/concourse/concourse/releases"),
+					ghttp.RespondWith(200, "[]"),
+					ghttp.VerifyHeader(http.Header{"Authorization": nil}),
+				),
+			)
+		})
+
+		It("sends one", func() {
+			_, err := client.ListReleases()
+			Ω(err).ShouldNot(HaveOccurred())
+		})
+	})
+})

in_command.go

@@ -25,9 +25,14 @@ func NewInCommand(github GitHub, writer io.Writer) *InCommand {
 }
 
 func (c *InCommand) Run(destDir string, request InRequest) (InResponse, error) {
+	err := os.MkdirAll(destDir, 0755)
+	if err != nil {
+		return InResponse{}, err
+	}
+
 	releases, err := c.github.ListReleases()
 	if err != nil {
-		return InResponse{}, nil
+		return InResponse{}, err
 	}
 
 	sort.Sort(byVersion(releases))
@@ -55,7 +60,7 @@ func (c *InCommand) Run(destDir string, request InRequest) (InResponse, error) {
 
 	assets, err := c.github.ListReleaseAssets(foundRelease)
 	if err != nil {
-		return InResponse{}, nil
+		return InResponse{}, err
 	}
 
 	for _, asset := range assets {
@@ -87,7 +92,7 @@ func (c *InCommand) Run(destDir string, request InRequest) (InResponse, error) {
 
 		err := c.downloadFile(url, path)
 		if err != nil {
-			return InResponse{}, nil
+			return InResponse{}, err
 		}
 	}
 

in_command_test.go

@@ -1,6 +1,7 @@
 package resource_test
 
 import (
+	"errors"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -25,6 +26,7 @@ var _ = Describe("In Command", func() {
 		inResponse resource.InResponse
 		inErr      error
 
+		tmpDir  string
 		destDir string
 	)
 
@@ -34,9 +36,11 @@ var _ = Describe("In Command", func() {
 		githubClient = &fakes.FakeGitHub{}
 		command = resource.NewInCommand(githubClient, ioutil.Discard)
 
-		destDir, err = ioutil.TempDir("", "github-release")
+		tmpDir, err = ioutil.TempDir("", "github-release")
 		Ω(err).ShouldNot(HaveOccurred())
 
+		destDir = filepath.Join(tmpDir, "destination")
+
 		server = ghttp.NewServer()
 		server.RouteToHandler("GET", "/example.txt", ghttp.RespondWith(200, "example.txt"))
 		server.RouteToHandler("GET", "/example.rtf", ghttp.RespondWith(200, "example.rtf"))
@@ -50,8 +54,11 @@ var _ = Describe("In Command", func() {
 	})
 
 	AfterEach(func() {
+		if server != nil {
 			server.Close()
-		Ω(os.RemoveAll(destDir)).Should(Succeed())
+		}
+
+		Ω(os.RemoveAll(tmpDir)).Should(Succeed())
 	})
 
 	buildRelease := func(id int, tag string) github.RepositoryRelease {
@@ -171,6 +178,29 @@ var _ = Describe("In Command", func() {
 					Ω(err).ShouldNot(HaveOccurred())
 				})
 			})
+
+			Context("when downloading an asset fails", func() {
+				BeforeEach(func() {
+					server.Close()
+					server = nil
+				})
+
+				It("returns an error", func() {
+					Ω(inErr).Should(HaveOccurred())
+				})
+			})
+
+			Context("when listing release assets fails", func() {
+				disaster := errors.New("nope")
+
+				BeforeEach(func() {
+					githubClient.ListReleaseAssetsReturns(nil, disaster)
+				})
+
+				It("returns the error", func() {
+					Ω(inErr).Should(Equal(disaster))
+				})
+			})
 		})
 
 		Context("when the specified version is not available", func() {
@@ -228,4 +258,16 @@ var _ = Describe("In Command", func() {
 			Ω(inErr).Should(HaveOccurred())
 		})
 	})
+
+	Context("when listing releases fails", func() {
+		disaster := errors.New("nope")
+
+		BeforeEach(func() {
+			githubClient.ListReleasesReturns(nil, disaster)
+		})
+
+		It("returns the error", func() {
+			Ω(inErr).Should(Equal(disaster))
+		})
+	})
 })

resources.go

@@ -1,10 +1,11 @@
 package resource
 
 type Source struct {
-	AccessToken string `json:"access_token"`
-
 	User       string `json:"user"`
 	Repository string `json:"repository"`
+
+	GitHubAPIURL string `json:"github_api_url"`
+	AccessToken  string `json:"access_token"`
 }
 
 type CheckRequest struct {