feat(storage): post support dynamic key name (#12677)

tburgin · web-flow · commit 9e761f961a2c · 2025-09-04T16:09:43.000-04:00
* feat(storage): post support dynamic key name

* review updates
diff --git a/storage/bucket.go b/storage/bucket.go
@@ -225,6 +225,11 @@ func (b *BucketHandle) SignedURL(object string, opts *SignedURLOptions) (string,
 // to be non-nil. You may need to set the GoogleAccessID and PrivateKey fields
 // in some cases. Read more on the [automatic detection of credentials] for this method.
 //
+// To allow the unauthenticated client to upload to any object name in the
+// bucket with a given prefix rather than a specific object name, you can pass
+// an empty string for object and set [PostPolicyV4Options].Conditions to
+// include [ConditionStartsWith]("$key", "prefix").
+//
 // [automatic detection of credentials]: https://pkg.go.dev/cloud.google.com/go/storage#hdr-Credential_requirements_for_signing
 func (b *BucketHandle) GenerateSignedPostPolicyV4(object string, opts *PostPolicyV4Options) (*PostPolicyV4, error) {
 	// Make a copy of opts so we don't modify the pointer parameter.
diff --git a/storage/post_policy_v4.go b/storage/post_policy_v4.go
@@ -252,9 +252,6 @@ func GenerateSignedPostPolicyV4(bucket, object string, opts *PostPolicyV4Options
 	if bucket == "" {
 		return nil, errors.New("storage: bucket must be non-empty")
 	}
-	if object == "" {
-		return nil, errors.New("storage: object must be non-empty")
-	}
 	now := utcNow()
 	if err := validatePostPolicyV4Options(opts, now); err != nil {
 		return nil, err
