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--- transformations:exclusiveaccess [2021/01/16 07:48] – dmitry
+++ transformations:exclusiveaccess [2021/06/19 20:16] – craigt
@@ Line 1: / Line 1: @@
-===== Start/finish exclusive access =====
+{{ transformations:ExclusiveAccessAction.png}}
+======START/FINISH EXCLUSIVE ACCESS======
+Category: Workflow / Internal \\
-Enforce mutually exclusive access to a resource for simultaneously executed workflows (tasks).
+\\
+=====Description=====
+Enforce mutually exclusive access to a resource for simultaneously executed workflows (tasks).\\
+\\
+=====Use cases=====
 The action is intended for avoiding access conflicts when two or more simultaneously executed workflows (tasks) attempt to access a resource (e.g. write into a file or web API) that can only be accessed by one workflow at a time. It's typically used to resolve access conflicts between several simultaneously executed instances of an EasyMorph Server task.
+\\
+=====Action settings=====
+^Setting^Description^
+|Mode|Select whether the action will start or stop exclusive access.  Options:  //Enforce exclusive access// or //Stop\\ enforcing access//. |
+|Resource name<sup>*</sup>|Enter a name for the resource.  The resource name is symbolic. It is only used to identify a resource for the action.\\ The name doesn't have to be the real name of the accessed resource. Although, it is recommended to give\\ resources meaningful identifiers for clarity.|
+<sup>*</sup> Setting can be specified using a [[:parameters|parameter]].\\
+\\
+=====Remarks=====
 The action works similarly to a railroad semaphore. When one workflow starts exclusive access to a resource using the action, all the other workflows running on the same computer and requiring access to the same resource will wait until the first workflow finishes the exclusive access. Once exclusive access is finished, one from the waiting workflows will proceed to access the same resource.
@@ Line 15: / Line 30: @@
 To make the synchronization work, all workflows must use the "Start/finish exclusive access" action configured to start access to a resource with the same name.
-=== Resource name ===
-The resource name is symbolic. It is only used to identify a resource for the action. The name doesn't have to be the real name of the accessed resource. Although, it is recommended to give resources meaningful identifiers for clarity.
-The resource name can be specified using a parameter.
-=== Remarks ===
 A workflow can start exclusive access to only one resource at a time. In order to start exclusive access to another resource, the previous exclusive access must be finished by using the action again but in the "Finish" mode. Nested locks are not supported.
@@ Line 27: / Line 36: @@
 If exclusive access is not finished explicitly, it will be finished automatically when workflow execution finishes. In such a case, a warning will be produced.
-The action can't be used to synchronize actions within the same workflow. For that, use the [[transformations:synchronize|"Synchronize" action]].
+The action can't be used to synchronize actions within the same workflow. For that, use the [[transformations:synchronize|Synchronize]] action.
 The action can't be used to resolve access conflicts for workflows running on different computers.
+\\
+=====See also=====
+  * [[transformations:synchronize|Synchronize]]
+  * [[transformations:wait|Wait]]