Update fails - TypeError: can't pickle module objects

Iulian_Olaru · January 20, 2020, 10:05pm

Hey guys, anyone has any idea where this is coming from ? in a previous post the idea was this is related to redis but it seems redis is running correctly on my server.

Trying to update the system on the latest version-12 developing branch on an up to date ubuntu 18

Traceback (most recent call last):
  File "/usr/lib/python3.6/runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/lib/python3.6/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/utils/bench_helper.py", line 97, in <module>
    main()
  File "/opt/erpnext/frappe12/apps/frappe/frappe/utils/bench_helper.py", line 18, in main
    click.Group(commands=commands)(prog_name='bench')
  File "/opt/erpnext/frappe12/env/lib/python3.6/site-packages/click/core.py", line 764, in __call__
    return self.main(*args, **kwargs)
  File "/opt/erpnext/frappe12/env/lib/python3.6/site-packages/click/core.py", line 717, in main
    rv = self.invoke(ctx)
  File "/opt/erpnext/frappe12/env/lib/python3.6/site-packages/click/core.py", line 1137, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/opt/erpnext/frappe12/env/lib/python3.6/site-packages/click/core.py", line 1137, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/opt/erpnext/frappe12/env/lib/python3.6/site-packages/click/core.py", line 956, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/opt/erpnext/frappe12/env/lib/python3.6/site-packages/click/core.py", line 555, in invoke
    return callback(*args, **kwargs)
  File "/opt/erpnext/frappe12/env/lib/python3.6/site-packages/click/decorators.py", line 17, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/commands/__init__.py", line 25, in _func
    ret = f(frappe._dict(ctx.obj), *args, **kwargs)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/commands/site.py", line 233, in migrate
    migrate(context.verbose, rebuild_website=rebuild_website, skip_failing=skip_failing)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/migrate.py", line 48, in migrate
    frappe.modules.patch_handler.run_all(skip_failing)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/modules/patch_handler.py", line 41, in run_all
    run_patch(patch)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/modules/patch_handler.py", line 30, in run_patch
    if not run_single(patchmodule = patch):
  File "/opt/erpnext/frappe12/apps/frappe/frappe/modules/patch_handler.py", line 71, in run_single
    return execute_patch(patchmodule, method, methodargs)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/modules/patch_handler.py", line 77, in execute_patch
    block_user(True)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/modules/patch_handler.py", line 127, in block_user
    frappe.db.set_global('__session_status', block and 'stop' or None)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/database/database.py", line 698, in set_global
    self.set_default(key, val, user)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/database/database.py", line 712, in set_default
    frappe.defaults.set_default(key, val, parent, parenttype)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/defaults.py", line 134, in set_default
    add_default(key, value, parent)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/defaults.py", line 147, in add_default
    d.insert(ignore_permissions=True)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/model/document.py", line 222, in insert
    self.run_method("before_insert")
  File "/opt/erpnext/frappe12/apps/frappe/frappe/model/document.py", line 787, in run_method
    out = Document.hook(fn)(self, *args, **kwargs)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/model/document.py", line 1052, in composer
    doc_events = frappe.get_doc_hooks()
  File "/opt/erpnext/frappe12/apps/frappe/frappe/__init__.py", line 899, in get_doc_hooks
    hooks = get_hooks('doc_events', {})
  File "/opt/erpnext/frappe12/apps/frappe/frappe/__init__.py", line 946, in get_hooks
    hooks = _dict(cache().get_value("app_hooks", load_app_hooks))
  File "/opt/erpnext/frappe12/apps/frappe/frappe/utils/redis_wrapper.py", line 80, in get_value
    self.set_value(original_key, val, user=user)
  File "/opt/erpnext/frappe12/apps/frappe/frappe/utils/redis_wrapper.py", line 48, in set_value
    self.set(key, pickle.dumps(val))
TypeError: can't pickle module objects

sjain · April 20, 2020, 1:22pm

Did you get any solution on this?

abrarpv97 · August 13, 2020, 5:31am

Any solution for this? i am also facing problem with this error

szufisher · August 17, 2020, 12:50pm

if custom code in custom app’s hooks.py includes imported module, there is such error, change the system conf to activate develop mode, then system will skip pickling hooks.py.

benknowles · August 18, 2020, 2:47am

Yes, this is the issue that I experienced.

In developer mode, the hooks are not cached which is why it works fine normally.

With developer mode off, hooks are cached. So when you import a module it’s trying to cache the dict() containing a module key which isn’t possible and that causes the pickle error.

Another workaround besides just turning on developer mode, is you can rewrite your imports to be like this: “import xyz as _xyz”

This works because the caching function skips any keys that begin with underscores.

szufisher · August 18, 2020, 3:36am

seems more cute workaround.

Update: confirm it is working

Manan_Shah · November 12, 2020, 4:45am

Hi
Can you please guide where to make this change? Which file and what is its location

abrarpv97 · November 12, 2020, 6:28am

@Manan_Shah i think in hooks.py in your custom app

Manan_Shah · November 15, 2020, 11:07am

Thanks for the reply
I see these two lines

from __future__ import unicode_literals

from . import __version__ as app_version

Do I need to change anything in these two lines?

What is the

referring to?

Manan_Shah · November 17, 2020, 4:46am

Hi
We need to change this line

to

from . import xyz as _xyz and run bench update, this solved the problem

shubhamgupta123 · February 10, 2021, 6:08am

I am getting this same error when trying to run bench migrate.
developer_mode is set as 1 in the site_config.json, yet this issue occurs.
Any help?

shubhamgupta123 · February 22, 2021, 10:48am

The only way I can get it to work is by changing the following in frappe/frappe/__init__.py,

no_cache = conf.developer_mode or False

if app_name:
	hooks = _dict(load_app_hooks(app_name))
else:
	if no_cache:
		hooks = _dict(load_app_hooks())
	else:
		hooks = _dict(cache().get_value("app_hooks", load_app_hooks))

It works if I explicitly set if True instead of if no_cache
Though it should work as no_cache is being set from conf.developer_mode, shouldn’t it?

Khang_Le · March 30, 2021, 3:06am

I removed custom app in apps.txt in sites but still get this error, do you have solution for this?

  File "/home/frappe/frappe-bench/apps/frappe/frappe/__init__.py", line 1034, in get_hooks
    hooks = _dict(cache().get_value("app_hooks", load_app_hooks))
  File "/home/frappe/frappe-bench/apps/frappe/frappe/utils/redis_wrapper.py", line 80, in get_value
    self.set_value(original_key, val, user=user)
  File "/home/frappe/frappe-bench/apps/frappe/frappe/utils/redis_wrapper.py", line 48, in set_value
    self.set(key, pickle.dumps(val))
TypeError: can't pickle module objects

brian_pond · April 30, 2021, 12:16am

Thank you, @benknowles and @szufisher

mwrsa · May 11, 2021, 6:35am

I am getting this error despite developer mode. Any thoughts on that? Thank you.

Edit: Thanks @shubhamgupta123, editing __init__.py did the trick!

Edit 2: Nope, does not work. As soon as I edit __init__.py, I have local changes in frappe app and cannot proceed with the update. Reverting the changes removes the necessary change in the file. git pull doesn’t work either - it reports to be current. So I am running in circles, unable to update.

neelbhanushali · June 10, 2021, 1:05pm

@rmehta @revant_one

Please go through this thread.

neelbhanushali · June 10, 2021, 1:29pm

@shubhamgupta123 This will interest you

Whenever patches are run, it comes to frappe.get_hooks method n times

n = 1 (for website_clear_cache hook) + num_of_apps_installed (for before_migrate hook) + 1 (for doc_events hook)

When it comes for the hook doc_events, for some reason conf.developer_mode is set to 0 which causes no_cache to be False

app_name	hook	default	conf.developer_mode	no_cache
None	website_clear_cache	None	True	True
frappe	before_migrate	None	True	True
custom_app	before_migrate	None	True	True
None	doc_events	None	0	False

It is the last time it comes to this method, it fails resulting in the pickle error.

@rmehta @revant_one please check if you could do something about this issue!

szufisher · June 11, 2021, 3:12am

try catch then bypass cache and the error as needed?

Vinod_Nadar · July 2, 2022, 7:26pm

For all the imports in hooks.py in my custom app, i updated import xyz as _xyz.

This issue is fixed

charleslcso · March 29, 2023, 4:26am

Isn’t running “bench update” a bit heavy handed? It also pulls changes for bench-repo and others too. Bench Commands Cheatsheet