Dashboard graphs are not drawn with 4.20 or 4.21

Hi,

I have been running 4.14 for a while, and today in order to get to a newer
version of werkzeug, I tried upgrading to 4.21 only to find that the
Dashboard graphs are not being drawn. All else seems fine (I can navigate
down to tables, and view data for example), but none of the graphs a re
drawn.

I notice that on the console from where I am running pgAdmin 4.21, I see
messages like this every few seconds:

SQL:flask.app:Execute (dict) for server #1 - DB:foo (Query-id: 8996147):
/*pga4dash*/
SELECT 'session_stats' AS chart_name, row_to_json(t) AS chart_data
FROM (SELECT
(SELECT count(*) FROM pg_stat_activity WHERE datname = (SELECT datname
FROM pg_database WHERE oid = 1680798)) AS "Total",
(SELECT count(*) FROM pg_stat_activity WHERE state = 'active' AND
datname = (SELECT datname FROM pg_database WHERE oid = 1680798)) AS
"Active",
(SELECT count(*) FROM pg_stat_activity WHERE state = 'idle' AND datname
= (SELECT datname FROM pg_database WHERE oid = 1680798)) AS "Idle"
) t
UNION ALL
...
more like this
...

which suggests something is trying to fetch the needed data. I tried
restarting the browser, to no avail.

I did also notice:

- A dependency on pyasn1.error which I resolved by updating from
pyasn1-0.4.5 to pyasn1-0.4.8:

Traceback (most recent call last):
File "/usr/local/lib/python3.7/dist-packages/pgadmin4/pgAdmin4.py", line
109, in <module>
app = create_app()
File
"/usr/local/lib/python3.7/dist-packages/pgadmin4/pgadmin/__init__.py", line
401, in create_app
authenticate.init_app(app)
File
"/usr/local/lib/python3.7/dist-packages/pgadmin4/pgadmin/authenticate/__init__.py",
line 154, in init_app
AuthSourceRegistry.load_auth_sources()
File
"/usr/local/lib/python3.7/dist-packages/pgadmin4/pgadmin/authenticate/registry.py",
line 65, in load_auth_sources
module = import_module(module_name)
File "/usr/lib/python3.7/importlib/__init__.py", line 127, in
import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
File "<frozen importlib._bootstrap>", line 983, in _find_and_load
File "<frozen importlib._bootstrap>", line 967, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 677, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 728, in exec_module
File "<frozen importlib._bootstrap>", line 219, in
_call_with_frames_removed
File
"/usr/local/lib/python3.7/dist-packages/pgadmin4/pgadmin/authenticate/ldap.py",
line 14, in <module>
from ldap3 import Connection, Server, Tls, ALL, ALL_ATTRIBUTES
File "/usr/local/lib/python3.7/dist-packages/ldap3/__init__.py", line
139, in <module>
from .core.connection import Connection
File "/usr/local/lib/python3.7/dist-packages/ldap3/core/connection.py",
line 44, in <module>
from ..operation.compare import compare_operation,
compare_request_to_dict
File "/usr/local/lib/python3.7/dist-packages/ldap3/operation/compare.py",
line 28, in <module>
from ..operation.search import ava_to_dict
File "/usr/local/lib/python3.7/dist-packages/ldap3/operation/search.py",
line 41, in <module>
from pyasn1.error import PyAsn1UnicodeDecodeError
ImportError: cannot import name 'PyAsn1UnicodeDecodeError' from
'pyasn1.error' (/usr/local/lib/python3.7/dist-packages/pyasn1/error.py)

- A compatibility problem with werkzeug. I had been running 0.15.2, and
tried upgrading to 1.0.1 to address some long standing issues (I believe
you guys were also hit by changes in legacy API support too) only to get
this:

Traceback (most recent call last):
File "/usr/local/lib/python3.7/dist-packages/pgadmin4/pgAdmin4.py", line
40, in <module>
import config
File "/usr/local/lib/python3.7/dist-packages/pgadmin4/config.py", line
30, in <module>
from pgadmin.utils import env, IS_PY2, IS_WIN, fs_short_path
File
"/usr/local/lib/python3.7/dist-packages/pgadmin4/pgadmin/__init__.py", line
21, in <module>
from flask_babelex import Babel, gettext
File "/usr/local/lib/python3.7/dist-packages/flask_babelex/__init__.py",
line 23, in <module>
from werkzeug import ImmutableDict
ImportError: cannot import name 'ImmutableDict' from 'werkzeug'
(/usr/local/lib/python3.7/dist-packages/werkzeug/__init__.py)

I downgraded to werkzeug 0.16.1 to address this.

The results I noted were AFTER these fixes were applied. FWIW, I am running
on a recent Ubuntu desktop.

Any advice welcome.

Thanks, Shaheed