1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
.. currentmodule:: globus_sdk
.. _userguide_scheduled_transfers:
Scheduling a Repeating Transfer
===============================
The Globus Timers service allows users to schedule tasks to run at a future
date or on a recurring schedule.
In particular, Timers allows scheduled ``Transfer Tasks``, which can be
submitted very similarly to submissions to the Globus Transfer service.
Creating a Transfer Timer
-------------------------
To setup recurring transfers, you will need to create a timer.
The timer *contains* a Transfer Task submission.
It will submit that Transfer Task each time it runs.
.. literalinclude:: create_timer.py
:caption: ``create_timer.py`` [:download:`download <create_timer.py>`]
:language: python
Discover Data Access Scopes and Create a Timer
----------------------------------------------
Unlike direct ``Transfer Task`` submission, creating a Timer with unknown inputs
won't give you an error immediately if you need ``data_access`` scopes because
that information isn't available until the Timer runs.
Therefore, if the input collections are variable, we need to enhance the previous
example to automatically determine whether or not the ``data_access`` scope is
needed.
We'll do this with a new ``uses_data_access`` helper and a :class:`TransferClient`:
.. code-block:: python
transfer_client = globus_sdk.TransferClient(app=USER_APP)
def uses_data_access(collection_id: str) -> bool:
"""
Use the `transfer_client` associated with the app to lookup the given
collection ID.
Having looked up the record, return `True` if it uses a `data_access` scope
and `False` otherwise.
"""
doc = transfer_client.get_endpoint(collection_id)
if doc["entity_type"] != "GCSv5_mapped_collection":
return False
if doc["high_assurance"]:
return False
return True
This will allow us to guard our use of the ``data_access`` scope thusly:
.. code-block:: python
if uses_data_access(SRC_COLLECTION):
timers_client.add_app_transfer_data_access_scope(SRC_COLLECTION)
if uses_data_access(DST_COLLECTION):
timers_client.add_app_transfer_data_access_scope(DST_COLLECTION)
.. note::
Because the ``data_access`` requirement can't be detected until after you have
logged in to the app, it is possible for this to result in a "double login"
scenario. First, you login providing consent for Timers and Transfer, but
then a ``data_access`` scope is found to be needed. You then have to login
again to satisfy that requirement.
The ``UserApp`` will track the addition until you use ``app.logout``,
however, so this only happens the first time the script runs.
With these modifications in place, the resulting script looks like so:
.. literalinclude:: create_timer_detect_data_access.py
:caption: ``create_timer_detect_data_access.py`` [:download:`download <create_timer_detect_data_access.py>`]
:language: python
|
