Handle the case when issue labels already exist

builtin/providers/github/resource_github_issue_label.go

@@ -10,9 +10,9 @@ import (
 
 func resourceGithubIssueLabel() *schema.Resource {
 	return &schema.Resource{
-		Create: resourceGithubIssueLabelCreate,
+		Create: resourceGithubIssueLabelCreateOrUpdate,
 		Read:   resourceGithubIssueLabelRead,
-		Update: resourceGithubIssueLabelUpdate,
+		Update: resourceGithubIssueLabelCreateOrUpdate,
 		Delete: resourceGithubIssueLabelDelete,
 		Importer: &schema.ResourceImporter{
 			State: schema.ImportStatePassthrough,
@@ -40,21 +40,54 @@ func resourceGithubIssueLabel() *schema.Resource {
 	}
 }
 
-func resourceGithubIssueLabelCreate(d *schema.ResourceData, meta interface{}) error {
+// resourceGithubIssueLabelCreateOrUpdate idempotently creates or updates an
+// issue label. Issue labels are keyed off of their "name", so pre-existing
+// issue labels result in a 422 HTTP error if they exist outside of Terraform.
+// Normally this would not be an issue, except new repositories are created with
+// a "default" set of labels, and those labels easily conflict with custom ones.
+//
+// This function will first check if the label exists, and then issue an update,
+// otherwise it will create. This is also advantageous in that we get to use the
+// same function for two schema funcs.
+
+func resourceGithubIssueLabelCreateOrUpdate(d *schema.ResourceData, meta interface{}) error {
 	client := meta.(*Organization).client
+	o := meta.(*Organization).name
 	r := d.Get("repository").(string)
 	n := d.Get("name").(string)
 	c := d.Get("color").(string)
-	label := github.Label{
+
+	label := &github.Label{
 		Name:  &n,
 		Color: &c,
 	}
 
-	log.Printf("[DEBUG] Creating label: %#v", label)
-	_, resp, err := client.Issues.CreateLabel(context.TODO(), meta.(*Organization).name, r, &label)
-	log.Printf("[DEBUG] Response from creating label: %s", *resp)
-	if err != nil {
-		return err
+	log.Printf("[DEBUG] Querying label existence %s/%s (%s)", o, r, n)
+	existing, _, _ := client.Issues.GetLabel(context.TODO(), o, r, n)
+
+	if existing != nil {
+		log.Printf("[DEBUG] Updating label: %s/%s (%s: %s)", o, r, n, c)
+
+		// Pull out the original name. If we already have a resource, this is the
+		// parsed ID. If not, it's the value given to the resource.
+		var oname string
+		if d.Id() == "" {
+			oname = n
+		} else {
+			_, oname = parseTwoPartID(d.Id())
+		}
+
+		_, _, err := client.Issues.EditLabel(context.TODO(), o, r, oname, label)
+		if err != nil {
+			return err
+		}
+	} else {
+		log.Printf("[DEBUG] Creating label: %s/%s (%s: %s)", o, r, n, c)
+		_, resp, err := client.Issues.CreateLabel(context.TODO(), o, r, label)
+		log.Printf("[DEBUG] Response from creating label: %s", *resp)
+		if err != nil {
+			return err
+		}
 	}
 
 	d.SetId(buildTwoPartID(&r, &n))
@@ -66,6 +99,7 @@ func resourceGithubIssueLabelRead(d *schema.ResourceData, meta interface{}) erro
 	client := meta.(*Organization).client
 	r, n := parseTwoPartID(d.Id())
 
+	log.Printf("[DEBUG] Reading label: %s/%s", r, n)
 	githubLabel, _, err := client.Issues.GetLabel(context.TODO(), meta.(*Organization).name, r, n)
 	if err != nil {
 		d.SetId("")
@@ -80,31 +114,12 @@ func resourceGithubIssueLabelRead(d *schema.ResourceData, meta interface{}) erro
 	return nil
 }
 
-func resourceGithubIssueLabelUpdate(d *schema.ResourceData, meta interface{}) error {
-	client := meta.(*Organization).client
-	r := d.Get("repository").(string)
-	n := d.Get("name").(string)
-	c := d.Get("color").(string)
-
-	_, originalName := parseTwoPartID(d.Id())
-	_, _, err := client.Issues.EditLabel(context.TODO(), meta.(*Organization).name, r, originalName, &github.Label{
-		Name:  &n,
-		Color: &c,
-	})
-	if err != nil {
-		return err
-	}
-
-	d.SetId(buildTwoPartID(&r, &n))
-
-	return resourceGithubIssueLabelRead(d, meta)
-}
-
 func resourceGithubIssueLabelDelete(d *schema.ResourceData, meta interface{}) error {
 	client := meta.(*Organization).client
 	r := d.Get("repository").(string)
 	n := d.Get("name").(string)
 
+	log.Printf("[DEBUG] Deleting label: %s/%s", r, n)
 	_, err := client.Issues.DeleteLabel(context.TODO(), meta.(*Organization).name, r, n)
 	return err
 }

builtin/providers/github/resource_github_issue_label_test.go

@@ -32,6 +32,13 @@ func TestAccGithubIssueLabel_basic(t *testing.T) {
 					testAccCheckGithubIssueLabelAttributes(&label, "bar", "FFFFFF"),
 				),
 			},
+			{
+				Config: testAccGitHubIssueLabelExistsConfig,
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckGithubIssueLabelExists("github_issue_label.test", &label),
+					testAccCheckGithubIssueLabelAttributes(&label, "enhancement", "FF00FF"),
+				),
+			},
 		},
 	})
 }
@@ -134,3 +141,16 @@ resource "github_issue_label" "test" {
   color      = "FFFFFF"
 }
 `, testRepo)
+
+var testAccGitHubIssueLabelExistsConfig string = fmt.Sprintf(`
+// Create a repository which has the default labels
+resource "github_repository" "test" {
+  name = "tf-acc-repo-label-abc1234"
+}
+
+resource "github_issue_label" "test" {
+  repository = "${github_repository.test.name}"
+  name       = "enhancement" // Important! This is a pre-created label
+  color      = "FF00FF"
+}
+`)

website/source/docs/providers/github/r/issue_label.html.markdown

@@ -6,16 +6,24 @@ description: |-
   Provides a GitHub issue label resource.
 ---
 
-# github\_issue_label
+# github_issue_label
 
 Provides a GitHub issue label resource.
 
 This resource allows you to create and manage issue labels within your
 Github organization.
 
+Issue labels are keyed off of their "name", so pre-existing issue labels result
+in a 422 HTTP error if they exist outside of Terraform. Normally this would not
+be an issue, except new repositories are created with a "default" set of labels,
+and those labels easily conflict with custom ones.
+
+This resource will first check if the label exists, and then issue an update,
+otherwise it will create.
+
 ## Example Usage
 
-```
+```hcl
 # Create a new, red colored label
 resource "github_issue_label" "test_repo" {
   repository = "test-repo"
@@ -29,5 +37,7 @@ resource "github_issue_label" "test_repo" {
 The following arguments are supported:
 
 * `repository` - (Required) The GitHub repository
+
 * `name` - (Required) The name of the label.
-* `color` - (Required) A 6 character hex code, without the leading #, identifying the color of the label.
+
+* `color` - (Required) A 6 character hex code, **without the leading #**, identifying the color of the label.