job-state: Do not allow updating of low-level job-state objects.

Low-level job-state objects tied to the batch system (such as those
that represent single-machine and slurm-api jobs) never get updated.
So, there is no point permitting it.

* ravanan/job-state.scm (job-state-status): Return only the job
status, not the updated job state.
* ravanan/workflow.scm (workflow-scheduler)[poll]: Accept only the job
status, not the updated job state, from job-state-status.
* ravanan/workflow.scm (<command-line-tool-state>)[job-state]: Remove
setter.

2 files changed, 31 insertions, 35 deletions

diff --git a/ravanan/job-state.scm b/ravanan/job-state.scm
index 3d620f2..34bba81 100644
--- a/ravanan/job-state.scm
+++ b/ravanan/job-state.scm
@@ -60,26 +60,25 @@
   "Return current status and updated state of job with @var{state} on
 @var{batch-system}. The status is one of the symbols @code{completed},
 @code{failed} or @code{pending}."
-  (values (cond
-           ;; Single machine jobs are run synchronously. So, they return success
-           ;; or failure immediately.
-           ((single-machine-job-state? state)
-            (if (single-machine-job-state-success? state)
-                'completed
-                'failed))
-           ;; Poll slurm for job state.
-           ((slurm-job-state? state)
-            (run-with-state
-             (job-state (slurm-job-state-job-id state)
-                        #:api-endpoint (slurm-api-batch-system-endpoint batch-system)
-                        #:jwt (slurm-api-batch-system-jwt batch-system))))
-           ;; For vector states, poll each state element and return 'completed
-           ;; only if all state elements have completed.
-           ((vector? state)
-            (or (vector-every (lambda (state-element)
-                                (case (job-state-status state-element batch-system)
-                                  ((completed) => identity)
-                                  (else #f)))
-                              state)
-                'pending)))
-          state))
+  (cond
+   ;; Single machine jobs are run synchronously. So, they return success or
+   ;; failure immediately.
+   ((single-machine-job-state? state)
+    (if (single-machine-job-state-success? state)
+        'completed
+        'failed))
+   ;; Poll slurm for job state.
+   ((slurm-job-state? state)
+    (run-with-state
+     (job-state (slurm-job-state-job-id state)
+                #:api-endpoint (slurm-api-batch-system-endpoint batch-system)
+                #:jwt (slurm-api-batch-system-jwt batch-system))))
+   ;; For vector states, poll each state element and return 'completed only if
+   ;; all state elements have completed.
+   ((vector? state)
+    (or (vector-every (lambda (state-element)
+                        (case (job-state-status state-element batch-system)
+                          ((completed) => identity)
+                          (else #f)))
+                      state)
+        'pending))))
diff --git a/ravanan/workflow.scm b/ravanan/workflow.scm
index 1ef9284..13deb6f 100644
--- a/ravanan/workflow.scm
+++ b/ravanan/workflow.scm
@@ -71,8 +71,7 @@
 (define-immutable-record-type <command-line-tool-state>
   (command-line-tool-state job-state formal-outputs)
   command-line-tool-state?
-  (job-state command-line-tool-state-job-state
-             set-command-line-tool-state-job-state)
+  (job-state command-line-tool-state-job-state)
   (formal-outputs command-line-tool-state-formal-outputs))
 
 (define-immutable-record-type <workflow-state>
@@ -334,16 +333,14 @@ exit if job has failed."
                   state)))
        ;; Poll job state. Raise an exception if the job has failed.
        ((command-line-tool-state? state)
-        (let ((status updated-job-state
-                      (job-state-status (command-line-tool-state-job-state state)
-                                        batch-system)))
-          (values (case status
-                    ((failed)
-                     (raise-exception (job-failure
-                                       (job-state-script
-                                        (command-line-tool-state-job-state state)))))
-                    (else => identity))
-                  (set-command-line-tool-state-job-state state updated-job-state))))
+        (values (case (job-state-status (command-line-tool-state-job-state state)
+                                        batch-system)
+                  ((failed)
+                   (raise-exception (job-failure
+                                     (job-state-script
+                                      (command-line-tool-state-job-state state)))))
+                  (else => identity))
+                state))
        ;; Poll sub-workflow state. We do not need to check the status here since
        ;; job failures only occur at the level of a CommandLineTool.
        ((workflow-state? state)