feat: Allow digest in image name (#744)

docs/data-sources/registry_image.md

@@ -28,7 +28,7 @@ resource "docker_image" "ubuntu" {
 
 ### Required
 
-- `name` (String) The name of the Docker image, including any tags. e.g. `alpine:latest`
+- `name` (String) The name of the Docker image, including any tags. e.g. `alpine:latest`. You can also specify a digest, e.g. `nginx:1.28.0@sha256:eaa7e36decc3421fc04478c586dfea0d931cebe47d5bc0b15d758a32ba51126f`.
 
 ### Optional
 

internal/provider/data_source_docker_registry_image.go

@@ -20,7 +20,7 @@ func dataSourceDockerRegistryImage() *schema.Resource {
 		Schema: map[string]*schema.Schema{
 			"name": {
 				Type:        schema.TypeString,
-				Description: "The name of the Docker image, including any tags. e.g. `alpine:latest`",
+				Description: "The name of the Docker image, including any tags. e.g. `alpine:latest`. You can also specify a digest, e.g. `nginx:1.28.0@sha256:eaa7e36decc3421fc04478c586dfea0d931cebe47d5bc0b15d758a32ba51126f`.",
 				Required:    true,
 			},
 

internal/provider/data_source_docker_registry_image_test.go

@@ -21,7 +21,7 @@ func TestAccDockerRegistryImage_basic(t *testing.T) {
 		ProviderFactories: providerFactories,
 		Steps: []resource.TestStep{
 			{
-				Config: loadTestConfiguration(t, DATA_SOURCE, "docker_registry_image", "testAccDockerImageDataSourceConfig"),
+				Config: fmt.Sprintf(loadTestConfiguration(t, DATA_SOURCE, "docker_registry_image", "testAccDockerImageDataSourceConfig"), "alpine:latest"),
 				Check: resource.ComposeTestCheckFunc(
 					resource.TestMatchResourceAttr("data.docker_registry_image.foo", "sha256_digest", registryDigestRegexp),
 				),
@@ -30,6 +30,21 @@ func TestAccDockerRegistryImage_basic(t *testing.T) {
 	})
 }
 
+func TestAccDockerRegistryImage_basicWithDigest(t *testing.T) {
+	resource.Test(t, resource.TestCase{
+		PreCheck:          func() { testAccPreCheck(t) },
+		ProviderFactories: providerFactories,
+		Steps: []resource.TestStep{
+			{
+				Config: fmt.Sprintf(loadTestConfiguration(t, DATA_SOURCE, "docker_registry_image", "testAccDockerImageDataSourceConfig"), "nginx:1.28.0@sha256:eaa7e36decc3421fc04478c586dfea0d931cebe47d5bc0b15d758a32ba51126f"),
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttr("data.docker_registry_image.foo", "sha256_digest", "sha256:eaa7e36decc3421fc04478c586dfea0d931cebe47d5bc0b15d758a32ba51126f"),
+				),
+			},
+		},
+	})
+}
+
 func TestAccDockerRegistryImage_private(t *testing.T) {
 	resource.Test(t, resource.TestCase{
 		PreCheck:          func() { testAccPreCheck(t) },

internal/provider/resource_docker_image_funcs.go

@@ -288,6 +288,12 @@ func parseImageOptions(image string) internalPullImageOptions {
 		// we have the tag, strip it
 		pullOpts.Repository = image[:prefixLength+tagIndex]
 		pullOpts.Tag = image[prefixLength+tagIndex+1:]
+		digestIndex := strings.Index(pullOpts.Tag, "@")
+		if digestIndex != -1 {
+			log.Printf("[INFO] Found digest in tag: %s, we are using the digest for pulling the image from the registry", pullOpts.Tag)
+			// prefer pinned digest over tag name
+			pullOpts.Tag = pullOpts.Tag[digestIndex+1:]
+		}
 	}
 
 	if pullOpts.Tag == "" {

testdata/data-sources/docker_registry_image/testAccDockerImageDataSourceConfig.tf

@@ -1,3 +1,3 @@
 data "docker_registry_image" "foo" {
-  name = "alpine:latest"
+  name = "%s"
 }