Allow for retrying postprocessing steps with an exponential backoff

services/postprocessing/pkg/config/config.go

@@ -28,6 +28,9 @@ type Postprocessing struct {
 	Events          Events        `yaml:"events"`
 	Steps           []string      `yaml:"steps" env:"POSTPROCESSING_STEPS" desc:"A list of postprocessing steps processed in order of their appearance. Currently supported values by the system are: 'virusscan', 'policies' and 'delay'. Custom steps are allowed. See the documentation for instructions. See the Environment Variable Types description for more details."`
 	Delayprocessing time.Duration `yaml:"delayprocessing" env:"POSTPROCESSING_DELAY" desc:"After uploading a file but before making it available for download, a delay step can be added. Intended for developing purposes only. If a duration is set but the keyword 'delay' is not explicitely added to 'POSTPROCESSING_STEPS', the delay step will be processed as last step. In such a case, a log entry will be written on service startup to remind the admin about that situation. See the Environment Variable Types description for more details."`
+
+	RetryBackoffDuration time.Duration `yaml:"retry_backoff_duration" env:"POSTPROCESSING_RETRY_BACKOFF_DURATION" desc:"The base for the exponential backoff duration before retrying a failed postprocessing step. See the Environment Variable Types description for more details."`
+	MaxRetries           int           `yaml:"max_retries" env:"POSTPROCESSING_MAX_RETRIES" desc:"The maximum number of retries for a failed postprocessing step. See the Environment Variable Types description for more details."`
 }
 
 // Events combines the configuration options for the event bus.

services/postprocessing/pkg/config/defaults/defaultconfig.go

@@ -1,6 +1,8 @@
 package defaults
 
 import (
+	"time"
+
 	"github.com/owncloud/ocis/v2/services/postprocessing/pkg/config"
 )
 
@@ -29,6 +31,8 @@ func DefaultConfig() *config.Config {
 				Endpoint: "127.0.0.1:9233",
 				Cluster:  "ocis-cluster",
 			},
+			RetryBackoffDuration: 5 * time.Second,
+			MaxRetries:           14,
 		},
 		Store: config.Store{
 			Store:    "memory",