fix(data_source_github_release_asset): base64 encode file

Per code review feedback from @stevehipwell
(#2514 (comment)),
this ensures `file` is base64-encoded.

Signed-off-by: Mike Ball <mikedball@gmail.com>

Author: mdb

github/acc_test.go

@@ -117,7 +117,7 @@ func TestMain(m *testing.M) {
 		// https://github.com/integrations/terraform-provider-github/releases/tag/v6.4.0
 		testPublicRelaseAssetId:           "207956097",
 		testPublicRelaseAssetName:         "terraform-provider-github_6.4.0_manifest.json",
-		testPublicReleaseAssetContent:     "{\n  \"version\": 1,\n  \"metadata\": {\n    \"protocol_versions\": [\n      \"5.0\"\n    ]\n  }\n}\n",
+		testPublicReleaseAssetContent:     "{\n  \"version\": 1,\n  \"metadata\": {\n    \"protocol_versions\": [\n      \"5.0\"\n    ]\n  }\n}",
 		testPublicTemplateRepository:      "template-repository",
 		testPublicTemplateRepositoryOwner: "template-repository",
 		testGHActionsAppInstallationId:    15368,

github/data_source_github_release_asset.go

@@ -2,6 +2,7 @@ package github
 
 import (
 	"context"
+	"encoding/base64"
 	"io"
 	"net/http"
 	"strconv"
@@ -41,7 +42,7 @@ func dataSourceGithubReleaseAsset() *schema.Resource {
 			"file": {
 				Type:        schema.TypeString,
 				Computed:    true,
-				Description: "The release asset file contents (requires `download_file` to be `true`",
+				Description: "The base64-encoded release asset file contents (requires `download_file` to be `true`",
 			},
 			"url": {
 				Type:        schema.TypeString,
@@ -158,8 +159,22 @@ func dataSourceGithubReleaseAssetRead(ctx context.Context, d *schema.ResourceDat
 	}
 
 	buf := new(strings.Builder)
-	if _, err := io.Copy(buf, resp.Body); err != nil {
-		return diag.FromErr(err)
+	encoder := base64.NewEncoder(base64.StdEncoding, buf)
+	defer encoder.Close()
+	buffer := make([]byte, 4096)
+	for {
+		n, err := resp.Body.Read(buffer)
+		if err != nil && err != io.EOF {
+			return diag.FromErr(err)
+		}
+		if n > 0 {
+			if _, err := encoder.Write(buffer[:n]); err != nil {
+				return diag.FromErr(err)
+			}
+		}
+		if err == io.EOF {
+			break
+		}
 	}
 
 	if err := d.Set("file", buf.String()); err != nil {

github/data_source_github_release_asset_test.go

@@ -1,6 +1,7 @@
 package github
 
 import (
+	"encoding/base64"
 	"fmt"
 	"testing"
 
@@ -14,6 +15,7 @@ func TestAccGithubReleaseAssetDataSource(t *testing.T) {
 	testReleaseAssetID := testAccConf.testPublicRelaseAssetId
 	testReleaseAssetName := testAccConf.testPublicRelaseAssetName
 	testReleaseAssetContent := testAccConf.testPublicReleaseAssetContent
+	base64EncodedAssetContent := base64.StdEncoding.EncodeToString([]byte(testReleaseAssetContent))
 
 	t.Run("queries and downloads specified asset ID", func(t *testing.T) {
 		config := fmt.Sprintf(`
@@ -38,7 +40,7 @@ func TestAccGithubReleaseAssetDataSource(t *testing.T) {
 							"data.github_release_asset.test", "name", testReleaseAssetName,
 						),
 						resource.TestCheckResourceAttr(
-							"data.github_release_asset.test", "file", testReleaseAssetContent,
+							"data.github_release_asset.test", "file", base64EncodedAssetContent,
 						),
 					),
 				},

website/docs/d/release_asset.html.markdown

@@ -85,4 +85,4 @@ data "github_release_asset" "example" {
 * `created_at` - Date the asset was created
 * `updated_at` - Date the asset was last updated
 * `browser_download_url` - Browser URL from which the release asset can be downloaded
-* `file` - The release asset file contents (requires `download_file` to be `true`)
+* `file` - The base64-encoded release asset file contents (requires `download_file` to be `true`)