With file versioning, Flywheel tracks changes to your data over time to support scientific reproducibility and regulatory compliance. File versioning allows you to restore or delete previous versions of a file in Flywheel.
This article gives an overview of file versioning and how to view, restore or delete previous versions of a file:
How does file versioning work?
All files in Flywheel have a version number starting at 1. If a file is modified or overwritten in Flywheel, the previous version is retained, and the latest version, version 2, becomes the active version.
All operations involving files in Flywheel will use the latest file version. For example, the latest file version is used to view, download, or select a file for gear input. Operations via the Flywheel SDK have the option to request a specific version.
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Uploading DICOM data that results in overwriting an existing file. For example, uploading an acquisition that already exists in that project.
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Running a utility or analysis gear that results in the output overwriting the previous run's output. For example, rerunning a DICOM to NIFTI conversion.
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Changes to file metadata, such as changing modality or classification.
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Uploading DICOM data in Project A to Project B. File versioning is scoped to each project.
Restoring a previous version

Deleting a previous version
Once you delete a version, that file can no longer be accessed. Deleting a previous version helps ensure that other users don't use a bad version of the file.
How to view file versions
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Sign in to Flywheel.
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Navigate to an acquisition file. When a file has more than 1 version, the file version icon
appears next to it.
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Hover over the file, and select the options menu
icon.
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Choose Version History from the dropdown menu.
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Previous file versions appear. From here, you can view previous file information, restore a previous version, or delete a previous version.
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If you restore a file, you will need to verify if you want to rerun gear rules that apply to the file.
When you run an analysis gear, the Gear creates an analysis output. To view versions of the analysis output file:
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Sign in to Flywheel.
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Select a project, and click the Analysis tab.
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Select an analysis to expand the information.
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The analysis results show the file version used for both the input file and the output file the gear created.
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Select the option menu
, and choose Version History.
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The previous file versions appear. From here you can view previous file metadata, restore a previous version, or delete a previous version
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Navigate to an attachment.
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When a file has more than 1 version, the file version icon
appears next to it.
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Hover over the file, and select the options menu
icon.
-
Choose Version History from the dropdown menu.
-
Previous versions of the file appear. From here you can view previous file information, restore a previous version, or delete a previous version.
