Add support for resource locks (#852)

* Add support for resource locks

* Patch unexpected API response header in the test fixture

Actual fix from the API side is expected in the next few weeks

* Update fixtures

Author: zliang-akamai

instances.go

@@ -81,6 +81,9 @@ type Instance struct {
 
 	// NOTE: MaintenancePolicy can only be used with v4beta.
 	MaintenancePolicy string `json:"maintenance_policy"`
+
+	// NOTE: Locks can only be used with v4beta.
+	Locks []LockType `json:"locks"`
 }
 
 // InstanceSpec represents a linode spec

locks.go

@@ -0,0 +1,66 @@
+package linodego
+
+import (
+	"context"
+)
+
+// LockType represents the type of lock that can be applied to a resource
+// NOTE: Locks can only be used with v4beta.
+type LockType string
+
+// LockType enums
+const (
+	LockTypeCannotDelete                 LockType = "cannot_delete"
+	LockTypeCannotDeleteWithSubresources LockType = "cannot_delete_with_subresources"
+)
+
+// LockedEntity represents the entity that is locked
+// NOTE: Locks can only be used with v4beta.
+type LockedEntity struct {
+	ID    int        `json:"id"`
+	Type  EntityType `json:"type"`
+	Label string     `json:"label"`
+	URL   string     `json:"url"`
+}
+
+// Lock represents a resource lock
+// NOTE: Locks can only be used with v4beta.
+type Lock struct {
+	ID       int          `json:"id"`
+	LockType LockType     `json:"lock_type"`
+	Entity   LockedEntity `json:"entity"`
+}
+
+// LockCreateOptions fields are those accepted by CreateLock
+// NOTE: Locks can only be used with v4beta.
+type LockCreateOptions struct {
+	EntityType EntityType `json:"entity_type"`
+	EntityID   int        `json:"entity_id"`
+	LockType   LockType   `json:"lock_type"`
+}
+
+// ListLocks returns a paginated list of Locks
+// NOTE: Locks can only be used with v4beta.
+func (c *Client) ListLocks(ctx context.Context, opts *ListOptions) ([]Lock, error) {
+	return getPaginatedResults[Lock](ctx, c, "locks", opts)
+}
+
+// GetLock gets a single Lock with the provided ID
+// NOTE: Locks can only be used with v4beta.
+func (c *Client) GetLock(ctx context.Context, lockID int) (*Lock, error) {
+	e := formatAPIPath("locks/%d", lockID)
+	return doGETRequest[Lock](ctx, c, e)
+}
+
+// CreateLock creates a lock for a resource
+// NOTE: Locks can only be used with v4beta.
+func (c *Client) CreateLock(ctx context.Context, opts LockCreateOptions) (*Lock, error) {
+	return doPOSTRequest[Lock](ctx, c, "locks", opts)
+}
+
+// DeleteLock deletes a single Lock with the provided ID
+// NOTE: Locks can only be used with v4beta.
+func (c *Client) DeleteLock(ctx context.Context, lockID int) error {
+	e := formatAPIPath("locks/%d", lockID)
+	return doDELETERequest(ctx, c, e)
+}