direct: fail bind when the deployment state cannot be read

.nextchanges/bundles/bind-unreadable-state.md

@@ -0,0 +1 @@
+Fix `bundle deployment bind` silently binding over a deployment state it could not read, which could take over a resource that was already managed by the bundle.

acceptance/bundle/deployment/bind/job/unreadable-state/databricks.yml

@@ -0,0 +1,7 @@
+bundle:
+  name: test-bundle
+
+resources:
+  jobs:
+    job_1:
+      name: Job 1

acceptance/bundle/deployment/bind/job/unreadable-state/output.txt

@@ -0,0 +1,21 @@
+
+=== Deploy job_1
+>>> [CLI] bundle deploy
+Uploading bundle files to /Workspace/Users/[USERNAME]/.bundle/test-bundle/default/files...
+Created jobs.job_1
+Files: 5 uploaded, 0 deleted
+Resources: 1 created, 0 changed, 0 deleted, 0 unchanged
+
+=== Leave behind a WAL from a different lineage, as a crashed deploy would
+=== Bind must refuse: the state cannot be read, so we cannot tell if job_1 is already managed
+
+>>> errcode [CLI] bundle deployment bind job_1 [EXTERNAL_JOB_ID] --auto-approve
+Error: cannot check whether resources.jobs.job_1 is already bound: reading state from [TEST_TMP_DIR]/.databricks/bundle/default/resources.json: WAL recovery failed: WAL lineage ("wal-lineage-bbb") does not match state lineage ("[UUID]")
+
+
+Exit code: 1
+
+=== Nothing was bound: the WAL is still there and no bind state was written
+>>> assert_exists.py .databricks/bundle/default/resources.json.wal
+
+>>> assert_not_exists.py .databricks/bundle/default/resources.json.temp-bind

acceptance/bundle/deployment/bind/job/unreadable-state/resources.json.wal

@@ -0,0 +1,2 @@
+{"lineage":"wal-lineage-bbb","serial":2}
+{"k":"resources.jobs.job_1","v":{"__id__":"1001","state":{"name":"Job 1"}}}

acceptance/bundle/deployment/bind/job/unreadable-state/script

@@ -0,0 +1,14 @@
+title "Deploy job_1"
+trace $CLI bundle deploy
+
+title "Leave behind a WAL from a different lineage, as a crashed deploy would"
+cp resources.json.wal .databricks/bundle/default/
+
+title "Bind must refuse: the state cannot be read, so we cannot tell if job_1 is already managed\n"
+job_id=$($CLI jobs create --json '{"name": "External Job"}' | jq -r '.job_id')
+add_repl "$job_id" EXTERNAL_JOB_ID
+trace errcode $CLI bundle deployment bind job_1 "$job_id" --auto-approve
+
+title "Nothing was bound: the WAL is still there and no bind state was written"
+trace assert_exists.py .databricks/bundle/default/resources.json.wal
+trace assert_not_exists.py .databricks/bundle/default/resources.json.temp-bind

acceptance/bundle/deployment/bind/job/unreadable-state/test.toml

@@ -0,0 +1,5 @@
+Cloud = false
+
+Ignore = ["resources.json.wal"]
+
+EnvMatrix.DATABRICKS_BUNDLE_ENGINE = ["direct"]

bundle/direct/bind.go

@@ -62,17 +62,22 @@ type BindResult struct {
 func (b *DeploymentBundle) Bind(ctx context.Context, client *databricks.WorkspaceClient, configRoot *config.Root, statePath, resourceKey, resourceID string) (*BindResult, error) {
 	// Check if the resource is already managed (bound to a different ID)
 	var checkStateDB dstate.DeploymentState
-	if err := checkStateDB.Open(ctx, statePath, dstate.WithRecovery(true), dstate.WithWrite(false)); err == nil {
-		existingID := checkStateDB.GetResourceID(resourceKey)
-		if _, err := checkStateDB.Finalize(ctx); err != nil {
-			log.Warnf(ctx, "failed to finalize state: %v", err)
-		}
-		if existingID != "" {
-			return nil, ErrResourceAlreadyBound{
-				ResourceKey: resourceKey,
-				ExistingID:  existingID,
-				NewID:       resourceID,
-			}
+	if err := checkStateDB.Open(ctx, statePath, dstate.WithRecovery(true), dstate.WithWrite(false)); err != nil {
+		// State that cannot be read is not the same as state without a binding:
+		// the resource may well be managed already, and binding on top of it
+		// would take over a resource whose ownership was never checked. A state
+		// file that does not exist yet opens successfully as an empty one.
+		return nil, fmt.Errorf("cannot check whether %s is already bound: %w", resourceKey, err)
+	}
+	existingID := checkStateDB.GetResourceID(resourceKey)
+	if _, err := checkStateDB.Finalize(ctx); err != nil {
+		log.Warnf(ctx, "failed to finalize state: %v", err)
+	}
+	if existingID != "" {
+		return nil, ErrResourceAlreadyBound{
+			ResourceKey: resourceKey,
+			ExistingID:  existingID,
+			NewID:       resourceID,
 		}
 	}