X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/efe3cb087cc269daa5e41f669ecbb4c0d14bcfc6..903b27b2f4b8b00c11525ff6c2f4eb383709d074:/lib/cloud/interfaces.go

diff --git a/lib/cloud/interfaces.go b/lib/cloud/interfaces.go
index 3f03b650b4..792e737a91 100644
--- a/lib/cloud/interfaces.go
+++ b/lib/cloud/interfaces.go
@@ -6,6 +6,7 @@ package cloud
 
 import (
 	"encoding/json"
+	"errors"
 	"io"
 	"time"
 
@@ -57,6 +58,8 @@ type Executor interface {
 	Execute(cmd string, stdin io.Reader) (stdout, stderr []byte, err error)
 }
 
+var ErrNotImplemented = errors.New("not implemented")
+
 // An ExecutorTarget is a remote command execution service.
 type ExecutorTarget interface {
 	// SSH server hostname or IP address, or empty string if
@@ -71,6 +74,9 @@ type ExecutorTarget interface {
 	// VerifyHostKey can use it to make outgoing network
 	// connections from the instance -- e.g., to use the cloud's
 	// "this instance's metadata" API.
+	//
+	// Return ErrNotImplemented if no verification mechanism is
+	// available.
 	VerifyHostKey(ssh.PublicKey, *ssh.Client) error
 }
 
@@ -105,12 +111,18 @@ type Instance interface {
 // All public methods of an InstanceSet, and all public methods of the
 // instances it returns, are goroutine safe.
 type InstanceSet interface {
-	// Create a new instance. If supported by the driver, add the
+	// Create a new instance with the given type, image, and
+	// initial set of tags. If supported by the driver, add the
 	// provided public key to /root/.ssh/authorized_keys.
 	//
+	// The given InitCommand should be executed on the newly
+	// created instance. This is optional for a driver whose
+	// instances' VerifyHostKey() method never returns
+	// ErrNotImplemented. InitCommand will be under 1 KiB.
+	//
 	// The returned error should implement RateLimitError and
 	// QuotaError where applicable.
-	Create(arvados.InstanceType, ImageID, InstanceTags, ssh.PublicKey) (Instance, error)
+	Create(arvados.InstanceType, ImageID, InstanceTags, InitCommand, ssh.PublicKey) (Instance, error)
 
 	// Return all instances, including ones that are booting or
 	// shutting down. Optionally, filter out nodes that don't have
@@ -128,6 +140,8 @@ type InstanceSet interface {
 	Stop()
 }
 
+type InitCommand string
+
 // A Driver returns an InstanceSet that uses the given InstanceSetID
 // and driver-dependent configuration parameters.
 //