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title: CWL version and API support
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Copyright (C) The Arvados Authors. All rights reserved.

SPDX-License-Identifier: CC-BY-SA-3.0
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h2. Upgrading to CWL v1.1

CWL v1.1 introduces several features to the standard that were previously available as Arvados extensions.  CWL v1.1 syntax is backwards compatible with v1.0, so you can just change @cwlVersion: v1.0@ to @cwlVersion: v1.1@ and update your script to using the standard features.  On Arvados, there is only one behavior change between CWL v1.0 and v1.1 to be aware of: for performance reasons, Directory listings are no longer loaded by default.  To control loading Directory listings, use "loadListing":https://www.commonwl.org/v1.1/CommandLineTool.html#CommandInputParameter or "LoadListingRequirement":https://www.commonwl.org/v1.1/CommandLineTool.html#LoadListingRequirement (the extension @cwltool:LoadListingRequirement@ is deprecated.)

If a step requires network access, use "NetworkAccess":https://www.commonwl.org/v1.1/CommandLineTool.html#NetworkAccess instead of the Arvados-specific "arv:APIRequirement":cwl-extensions.html#APIRequirement .

To prevent misbehaving steps from running forever and wasting resources, you can fail the step if it exceeds a certain running time with "ToolTimeLimit":https://www.commonwl.org/v1.1/CommandLineTool.html#ToolTimeLimit instead of the deprecated @cwltool:TimeLimit@ .

To control if an individual step can be reused, use "WorkReuse":https://www.commonwl.org/v1.1/CommandLineTool.html#WorkReuse instead of the deprecated @arv:ReuseRequirement@.