r/github_repository: Allow updating default_branch

github/resource_github_repository.go

@@ -2,6 +2,7 @@ package github
 
 import (
 	"context"
+	"fmt"
 	"log"
 
 	"github.com/google/go-github/github"
@@ -68,15 +69,17 @@ func resourceGithubRepository() *schema.Resource {
 				Type:     schema.TypeBool,
 				Optional: true,
 			},
+			"default_branch": {
+				Type:        schema.TypeString,
+				Optional:    true,
+				Computed:    true,
+				Description: "Can only be set after initial repository creation, and only if the target branch exists",
+			},
 
 			"full_name": {
 				Type:     schema.TypeString,
 				Computed: true,
 			},
-			"default_branch": {
-				Type:     schema.TypeString,
-				Computed: true,
-			},
 			"ssh_clone_url": {
 				Type:     schema.TypeString,
 				Computed: true,
@@ -130,6 +133,10 @@ func resourceGithubRepositoryObject(d *schema.ResourceData) *github.Repository {
 func resourceGithubRepositoryCreate(d *schema.ResourceData, meta interface{}) error {
 	client := meta.(*Organization).client
 
+	if _, ok := d.GetOk("default_branch"); ok {
+		return fmt.Errorf("Cannot set the default branch on a new repository.")
+	}
+
 	repoReq := resourceGithubRepositoryObject(d)
 	log.Printf("[DEBUG] create github repository %s/%s", meta.(*Organization).name, *repoReq.Name)
 	repo, _, err := client.Repositories.Create(context.TODO(), meta.(*Organization).name, repoReq)
@@ -181,6 +188,10 @@ func resourceGithubRepositoryRead(d *schema.ResourceData, meta interface{}) erro
 func resourceGithubRepositoryUpdate(d *schema.ResourceData, meta interface{}) error {
 	client := meta.(*Organization).client
 	repoReq := resourceGithubRepositoryObject(d)
+	// Can only set `default_branch` on an already created repository with the target branches ref already in-place
+	defaultBranch := d.Get("default_branch").(string)
+	repoReq.DefaultBranch = &defaultBranch
+
 	repoName := d.Id()
 	log.Printf("[DEBUG] update github repository %s/%s", meta.(*Organization).name, repoName)
 	repo, _, err := client.Repositories.Edit(context.TODO(), meta.(*Organization).name, repoName, repoReq)

github/resource_github_repository_test.go

@@ -3,6 +3,7 @@ package github
 import (
 	"context"
 	"fmt"
+	"os"
 	"strings"
 	"testing"
 
@@ -80,6 +81,62 @@ func TestAccGithubRepository_importBasic(t *testing.T) {
 	})
 }
 
+func TestAccGithubRepository_defaultBranch(t *testing.T) {
+	var repo github.Repository
+	randString := acctest.RandStringFromCharSet(10, acctest.CharSetAlphaNum)
+	name := fmt.Sprintf("tf-acc-test-%s", randString)
+	description := fmt.Sprintf("Terraform acceptance tests %s", randString)
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckGithubRepositoryDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccGithubRepositoryConfigDefaultBranch(randString),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckGithubRepositoryExists("github_repository.foo", &repo),
+					testAccCheckGithubRepositoryAttributes(&repo, &testAccGithubRepositoryExpectedAttributes{
+						Name:             name,
+						Description:      description,
+						Homepage:         "http://example.com/",
+						HasIssues:        true,
+						HasWiki:          true,
+						AllowMergeCommit: true,
+						AutoInit:         true,
+						AllowSquashMerge: false,
+						AllowRebaseMerge: false,
+						HasDownloads:     true,
+						DefaultBranch:    "master",
+					}),
+				),
+			},
+			{
+				PreConfig: func() {
+					testAccCreateRepositoryBranch("foo", *repo.Name)
+				},
+				Config: testAccGithubRepositoryUpdateConfigDefaultBranch(randString),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckGithubRepositoryExists("github_repository.foo", &repo),
+					testAccCheckGithubRepositoryAttributes(&repo, &testAccGithubRepositoryExpectedAttributes{
+						Name:             name,
+						Description:      "Updated " + description,
+						Homepage:         "http://example.com/",
+						AutoInit:         true,
+						HasIssues:        true,
+						HasWiki:          true,
+						AllowMergeCommit: true,
+						AllowSquashMerge: false,
+						AllowRebaseMerge: false,
+						HasDownloads:     true,
+						DefaultBranch:    "foo",
+					}),
+				),
+			},
+		},
+	})
+}
+
 func testAccCheckGithubRepositoryExists(n string, repo *github.Repository) resource.TestCheckFunc {
 	return func(s *terraform.State) error {
 		rs, ok := s.RootModule().Resources[n]
@@ -114,6 +171,7 @@ type testAccGithubRepositoryExpectedAttributes struct {
 	AllowSquashMerge bool
 	AllowRebaseMerge bool
 	HasDownloads     bool
+	AutoInit         bool
 
 	DefaultBranch string
 }
@@ -156,6 +214,12 @@ func testAccCheckGithubRepositoryAttributes(repo *github.Repository, want *testA
 			return fmt.Errorf("got default branch %q; want %q", *repo.DefaultBranch, want.DefaultBranch)
 		}
 
+		if repo.AutoInit != nil {
+			if *repo.AutoInit != want.AutoInit {
+				return fmt.Errorf("got auto init %t; want %t", *repo.AutoInit, want.AutoInit)
+			}
+		}
+
 		// For the rest of these, we just want to make sure they've been
 		// populated with something that seems somewhat reasonable.
 		if !strings.HasSuffix(*repo.FullName, "/"+want.Name) {
@@ -213,6 +277,42 @@ func testAccCheckGithubRepositoryDestroy(s *terraform.State) error {
 	return nil
 }
 
+func testAccCreateRepositoryBranch(branch, repository string) error {
+	org := os.Getenv("GITHUB_ORGANIZATION")
+	token := os.Getenv("GITHUB_TOKEN")
+
+	config := Config{
+		Token:        token,
+		Organization: org,
+	}
+
+	c, err := config.Client()
+	if err != nil {
+		panic(fmt.Sprintf("Error creating github client: %s", err))
+	}
+	client := c.(*Organization).client
+
+	refs, _, err := client.Git.GetRefs(context.TODO(), org, repository, "heads")
+	if err != nil {
+		panic(fmt.Sprintf("Error getting reference commit: %s", err))
+	}
+	ref := refs[0]
+
+	newRef := &github.Reference{
+		Ref: github.String(fmt.Sprintf("refs/heads/%s", branch)),
+		Object: &github.GitObject{
+			SHA: ref.Object.SHA,
+		},
+	}
+
+	_, _, err = client.Git.CreateRef(context.TODO(), org, repository, newRef)
+	if err != nil {
+		panic(fmt.Sprintf("Error creating git reference: %s", err))
+	}
+
+	return nil
+}
+
 func testAccGithubRepositoryConfig(randString string) string {
 	return fmt.Sprintf(`
 resource "github_repository" "foo" {
@@ -254,3 +354,48 @@ resource "github_repository" "foo" {
 }
 `, randString, randString)
 }
+
+func testAccGithubRepositoryConfigDefaultBranch(randString string) string {
+	return fmt.Sprintf(`
+resource "github_repository" "foo" {
+  name = "tf-acc-test-%s"
+  description = "Terraform acceptance tests %s"
+  homepage_url = "http://example.com/"
+
+  # So that acceptance tests can be run in a github organization
+  # with no billing
+  private = false
+
+  has_issues = true
+  has_wiki = true
+  allow_merge_commit = true
+  allow_squash_merge = false
+  allow_rebase_merge = false
+  has_downloads = true
+  auto_init = true
+}
+`, randString, randString)
+}
+
+func testAccGithubRepositoryUpdateConfigDefaultBranch(randString string) string {
+	return fmt.Sprintf(`
+resource "github_repository" "foo" {
+  name = "tf-acc-test-%s"
+  description = "Updated Terraform acceptance tests %s"
+  homepage_url = "http://example.com/"
+
+  # So that acceptance tests can be run in a github organization
+  # with no billing
+  private = false
+
+  has_issues = true
+  has_wiki = true
+  allow_merge_commit = true
+  allow_squash_merge = false
+  allow_rebase_merge = false
+  has_downloads = true
+  auto_init = true
+  default_branch = "foo"
+}
+`, randString, randString)
+}

website/docs/r/repository.html.markdown

@@ -56,14 +56,16 @@ The following arguments are supported:
 * `auto_init` - (Optional) Meaningful only during create; set to `true` to
   produce an initial commit in the repository.
 
+* `default_branch` - (Optional) The name of the default branch of the repository. **NOTE:** This can only be set after a repository has already been created,
+and after a correct reference has been created for the target branch inside the repository. This means a user will have to omit this parameter from the
+initial repository creation and create the target branch inside of the repository prior to setting this attribute.
+
 ## Attributes Reference
 
 The following additional attributes are exported:
 
 * `full_name` - A string of the form "orgname/reponame".
 
-* `default_branch` - The name of the repository's default branch.
-
 * `ssh_clone_url` - URL that can be provided to `git clone` to clone the
   repository via SSH.