1

tried:

  • run as administrator;
  • install as administrator;
  • add path C:\Program Files\PostgreSQL\13\bin to system environment variables;
  • remove C:\Users\YourUsernameOrAdmin\AppData\Roaming\pgAdmin;
  • launch in cmd;
  • remove python;
  • install old python versions;
  • change default port;
  • pc and user name Latin;

when launch pgAdmin 4:

The pgAdmin 4 server could not be contacted:
Traceback (most recent call last):
  File "C:\Program Files\PostgreSQL\13\pgAdmin 4\web\pgAdmin4.py", line 98, in <module>
    app = create_app()
  File "C:\Program Files\PostgreSQL\13\pgAdmin 4\web\pgadmin\__init__.py", line 347, in create_app
    if not os.path.exists(SQLITE_PATH) or get_version() == -1:
  File "C:\Program Files\PostgreSQL\13\pgAdmin 4\web\pgadmin\setup\db_version.py", line 19, in get_version
    return version.value
AttributeError: 'NoneType' object has no attribute 'value'

db_version.py:

from db_upgrade import Version 

def get_version():
    try:
        version = Version.query.filter_by(name='ConfigDB').first()
    except Exception:
        return -1

    return version.value


def set_version(new_version):
    version = Version.query.filter_by(name='ConfigDB').first()
    version.value = new_version

PyCharm says: Cannot find reference 'Version' in 'db_upgrade.py'

db_upgrade.py:

import os
import flask_migrate

from pgadmin import db


def db_upgrade(app):
    from pgadmin.utils import u_encode, fs_encoding
    with app.app_context():
        flask_migrate.Migrate(app, db)
        migration_folder = os.path.join(
            os.path.dirname(os.path.realpath(u_encode(__file__, fs_encoding))),
            os.pardir, os.pardir,
            'migrations'
        )
        flask_migrate.upgrade(migration_folder)
Alexander Emelyanov
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  • Have you checked similar questions, e.g. [this one](https://stackoverflow.com/questions/43211296/pgadmin4-postgresql-application-server-could-not-be-contacted) – m.i.cosacak May 16 '21 at 16:41
  • 1
    @m.i.cosacak yes, tried: run as administrator; install as administrator; add path C:\Program Files\PostgreSQL\13\bin to system environment variables; remove C:\Users\YourUsernameOrAdmin\AppData\Roaming\pgAdmin; launch in cmd; remove python; install old python versions; change default port; pc and user name Latin; – Alexander Emelyanov May 16 '21 at 17:11
  • Hi @AlexanderEmelyanov, I was facing the same issue and this answer worked me like a charm. https://stackoverflow.com/a/45823367/7423854 – SHUBHAM AGRAWAL Jun 06 '21 at 13:12

0 Answers0