Sharing and receiving data
==========================

Globus enables you to securely share data with and receive data from external collaborators without requiring them 
to have a local account on the storage system. You can create a **Guest Collection** from a specific folder within one 
of your **Globus Collections**. This allows you to grant collaborators specific permissions (read-only or read-write) 
to that folder, making it easy to share data with them or provide a location for them to upload data to you.


Prerequisites
-------------
To share or receive data using Globus, you will need:

- A **Globus Collection** at the storage location where you wish to share or receive data. If none of the 
  `UoY collections <https://app.globus.org/collections?q=UoY&scope=all>`_ point to where your data is located, 
  you will need to :ref:`request a new collection <request-a-collection>`.
- The **Globus identity** of your external collaborator. If they do not have a Globus ID, they can create one on the 
  `Globus website <https://www.globusid.org/create>`_.

.. note::
    Collaborators must provide you with their **primary** Globus identity, since 
    `UoY collections <https://app.globus.org/collections?q=UoY&scope=all>`_ 
    are set up as `High Assurance <https://docs.globus.org/guides/overviews/high-assurance/>`_ collections.
    Therefore, giving access to a linked Globus identity will not be sufficient for the collaborator to access the data.


Creating a Guest Collection
---------------------------

A **Guest Collection** allows you to make a specific folder within a **Globus Collection** accessible to others.

1.  **Navigate to the Folder**: Log in to the `Globus web app <https://app.globus.org>`_ and open the 
    `File Manager <https://app.globus.org/file-manager>`_. Navigate to the **Globus Collection** and then to the 
    specific folder you wish to share.

2.  **Initiate Sharing**: Select the folder and click on :guilabel:`Share` located in the right-hand panel.

3.  **Add a Guest Collection**: Click the :guilabel:`Add Guest Collection` button. You will be prompted to provide 
    a **Display Name** for this new share. Optionally, you can also add a description and/or keywords. Click 
    :guilabel:`Create Collection`.

4.  **Add Permissions**: After creating the **Guest Collection**, you must grant permissions to your collaborator.

    - On the :guilabel:`Permissions` tab, click the :guilabel:`Add Permissions - Share With` button.
    - Verify that the **Path** field points to the correct folder you want to share.
    - Ensure that **user - share with specific individuals** is selected and enter your collaborator's Globus identity 
      in the **Username or Email** field.
    - Choose the permissions you want to grant: **read** or **read-write**.
    - Click :guilabel:`Add Permission` to finalise the permissions setup.

.. warning::
    Granting **write** permissions allows collaborators to modify or delete your files.

.. tip::
    For the fastest transfer speeds when sharing with external collaborators, it is recommended to create your 
    **Guest Collection** from a folder located on one of the **Viking Globus collections**:
     
        * `UoY - Viking2 Scratch Projects <https://app.globus.org/file-manager/collections/29929ac0-0e89-435f-abae-bbfe422d7768/overview>`_
        * `UoY - Viking2 Scratch Users <https://app.globus.org/file-manager/collections/ccd1e1d8-9a3c-49b6-9e01-7c1fd863b5ef/overview>`_
        * `UoY - Viking2 Longship Projects SE <https://app.globus.org/file-manager/collections/60dc7322-2782-40b5-8095-93f8de251f8c/overview>`_


Accessing the Guest Collection
------------------------------
Once a collaborator has been granted access, they will receive an email notification with a link to open the **Guest Collection**. They have two primary methods for accessing or adding data:

- **Browser-based HTTPS**: For individual files or small folders, the collaborator can use the :guilabel:`Download` or 
  :guilabel:`Upload` buttons in the right-hand panel of the Globus web interface.
- **Globus Transfer**: For large datasets, the most reliable method is a Globus transfer. The collaborator can install 
  `Globus Connect Personal <https://www.globus.org/globus-connect-personal>`_, which turns their personal laptop or desktop 
  into a fully functional Globus collection. They can then initiate a transfer between the shared **Guest Collection** and their personal collection.


Further assistance
------------------
For a more detailed description including screenshots on how to share and receive data using Globus, please refer to 
this tutorial: `How To Share Data Using Globus <https://docs.globus.org/guides/tutorials/manage-files/share-files/>`_