Mount artifacts to /tmp to avoid permissions

Custom base images may be built specificallly to avoid granting root
privileges. Without these privileges the local mount points cannot be
created if they live at the root of the filesystem.

sdk/python/kfp/v2/components/types/artifact_types.py

@@ -19,9 +19,9 @@
 import os
 from typing import Dict, Generic, List, Optional, Type, TypeVar, Union
 
-_GCS_LOCAL_MOUNT_PREFIX = '/gcs/'
-_MINIO_LOCAL_MOUNT_PREFIX = '/minio/'
-_S3_LOCAL_MOUNT_PREFIX = '/s3/'
+_GCS_LOCAL_MOUNT_PREFIX = '/tmp/gcs/'
+_MINIO_LOCAL_MOUNT_PREFIX = '/tmp/minio/'
+_S3_LOCAL_MOUNT_PREFIX = '/tmp/s3/'
 
 
 class Artifact(object):

v2/component/launcher.go

@@ -652,13 +652,13 @@ func (l *Launcher) generateOutputURI(name string) string {
 
 func localPathForURI(uri string) (string, error) {
 	if strings.HasPrefix(uri, "gs://") {
-		return "/gcs/" + strings.TrimPrefix(uri, "gs://"), nil
+		return "/tmp/gcs/" + strings.TrimPrefix(uri, "gs://"), nil
 	}
 	if strings.HasPrefix(uri, "minio://") {
-		return "/minio/" + strings.TrimPrefix(uri, "minio://"), nil
+		return "/tmp/minio/" + strings.TrimPrefix(uri, "minio://"), nil
 	}
 	if strings.HasPrefix(uri, "s3://") {
-		return "/s3/" + strings.TrimPrefix(uri, "s3://"), nil
+		return "/tmp/s3/" + strings.TrimPrefix(uri, "s3://"), nil
 	}
 	return "", fmt.Errorf("failed to generate local path for URI %s: unsupported storage scheme", uri)
 }