I can connect to a SAP SQL Anywhere database with FreeTDS and pyodbc as follows:
# hello_sybase.py
import pyodbc
try:
con = pyodbc.connect('Driver={FreeTDS};'
'Server=10.60.1.6,2638;'
'Database=blabla;'
'uid=blabla;pwd=blabla')
cur = con.cursor()
cur.execute("Select * from Test")
for row in cur.fetchall():
print (row)
cur.close()
con.close()
except Exception as e:
print(str(e))
I tried to connect in a Django view as follows:
import pyodbc
CONN_STRING = 'Driver={FreeTDS};Server=10.60.1.6,2638;Database=blabla;uid=blabla;pwd=blabla'
def my_view(request):
with pyodbc.connect(CONN_STRING) as conn:
cur = conn.cursor()
cur.execute('SELECT * FROM test')
rows = list(cur.fetchall())
return render(request, 'my_template.html', {'rows': rows})
When I run python manage.py runserver and run the code in the above view.
I have this error message
'08001', '[08001] [FreeTDS][SQL Server]Unable to connect to data source (0) (SQLDriverConnect)')
I tried to put TDS_Version=7.4 as was mentioned here in the comment, but it didn't helped.
Is it possible that these are issues with the threading as is said in that comment?
How can I fix it? The code works without Django, but with python manage.py runserver it doesn't work.
To be more precise, I use this code snippet in the view
if second_form.is_valid():
try:
con = pyodbc.connect(CONN_STRING)
con.setdecoding(pyodbc.SQL_CHAR, encoding='cp1252')
con.setdecoding(pyodbc.SQL_WCHAR, encoding='cp1252')
con.setencoding(encoding='cp1252')
cur = con.cursor()
cur.execute("Select * from test")
result2 = list(cur.fetchall())
print(results2)
cur.close()
con.close()
context['result2'] = result2
context['form2'] = SecondForm(request.POST)
except Exception as e:
print (str(e))
Here is about the error message
This SQLSTATE is returned for one or more of the following reasons:
Db2 ODBC is not able to establish a connection with the data source.
The connection request is rejected because a connection that was established with embedded SQL already exists.
Is it problem with my FreeTDS version? How can I safely upgrade it on Ubuntu 18.04?
I'm using Python for some tests and I would like to be able to run a SQL query via REST. Is there an easy way to use requests to run queries like:
requests.get('http:myserver:9000/exec' query="select * from my_table")
If you need to use REST via Python, this can be done similar to the following example:
import requests
import json
host = 'http://myserver:9000'
sql_query = "select * from my_table limit 100"
query_params = {'query': sql_query}
try:
response = requests.post(host + '/exec', params=query_params)
json_response = json.loads(response.text)
rows = json_response['dataset']
for row in rows:
print(row)
except requests.exceptions.RequestException as e:
print("Error: %s" % (e))
There is additional documentation for this on the QuestDB REST docs page
am new in python and i made a program to add data from a form to database am using wamp server here is my app.py code
import web
import MySQLdb
urls = (
'/', 'Index'
)
app = web.application(urls, globals())
render = web.template.render('templates/', base = "layout")
class Index(object):
def GET(self):
return render.hello_form()
def POST(self): #Open database connection
try:
db = MySQLdb.connect("localhost", "root", "", "testdb")
# prepare a cursor object using cursor() method
cursor = db.cursor()
# Prepare SQL query to INSERT a record into the database.
sql = "INSERT INTO details(name, address,) VALUES ("[self.name.text, self.address.text])""
try:
# Execute the SQL command
cursor.execute(sql)
# Commit your changes in the database
db.commit()
except:
# Rollback in case there is any error
db.rollback()
# disconnect from server
db.close()
finally:
form = web.input(name = "Nobody", greet = "Hello")
greeting = "%s, %s" % (form.name, form.address)
return render.index(greeting = greeting)
if __name__ == '__main__':
main()
and my error is Expected an indended block at line 12(return.render.hello_form)
can any one help pls..?
Scope is determined in python by indentation. As a result, you need to indent the try statement as it is inside the function POST. Also, the formatting on finally (and db.close()) looks wrong. Check out the this SO question, this guide and the Pep 8 guide on best practice code formatting. Also, be careful not to mix spaces and tabs as this can cause problems.
I have a task like this in Django:
from celery import task
import subprocess, celery
#celery.task
def file(password, source12, destination):
return subprocess.Popen(['sshpass', '-p', password, 'rsync', '-avz', '--info=progress2', source12, destination],
stderr=subprocess.PIPE, stdout=subprocess.PIPE).communicate()[0]
This transfers file from one server to another using rsync.
Here's my views:
def sync(request):
"""Sync the files into the server with the progress bar"""
choices = request.POST.getlist('choice')
for i in choices:
new_source = source +"/"+ i
start_date1 = datetime.datetime.utcnow().replace(tzinfo=utc)
source12 = new_source.replace(' ', '') #Remove whitespaces
result = file.delay(password, source12, destination)
result.get()
a = result.ready()
start_date = start_date1.strftime("%B %d, %Y, %H:%M%p")
extension = os.path.splitext(i)[1][1:] #Get the file_extension
fullname = os.path.join(destination, i) #Get the file_full_size to calculate size
st = int(os.path.getsize(fullname))
f_size = size(st, system=alternative)
I want to update the table in database which I want to update and show it to the user. The table should be updated while the file is being transferred. How can I do that using django-celery?
There is nothing too special about Celery when it comes to Django. You can just update the database like you would normally do. The only thing you may need to think about are the transactions.
Just to be sure I would recommend using either manual commits or autocommits to update the database. Although I would suggest using redis/memcached instead of the database for these kind of status updates. They are more suited for this purpose.
I'm trying to run
./manage.py test
But it tells me
Got an error creating the test database: permission denied to create database
Obviously it doesn't have permission to create the database, but I'm on a shared server, so there's not much I can do about that. I can create a new database through the control panel but I don't think there's any way I can let Django do it automatically.
So, can't I create the test database manually and instead tell Django to flush it every time, rather than recreating the whole thing?
I had a similar issue. But I wanted Django to just bypass the creation of a test database for one of my instances (it is not a mirror tough). Following Mark's suggestion, I created a custom test runner, as follows
from django.test.simple import DjangoTestSuiteRunner
class ByPassableDBDjangoTestSuiteRunner(DjangoTestSuiteRunner):
def setup_databases(self, **kwargs):
from django.db import connections
old_names = []
mirrors = []
for alias in connections:
connection = connections[alias]
# If the database is a test mirror, redirect its connection
# instead of creating a test database.
if connection.settings_dict['TEST_MIRROR']:
mirrors.append((alias, connection))
mirror_alias = connection.settings_dict['TEST_MIRROR']
connections._connections[alias] = connections[mirror_alias]
elif connection.settings_dict.get('BYPASS_CREATION','no') == 'no':
old_names.append((connection, connection.settings_dict['NAME']))
connection.creation.create_test_db(self.verbosity, autoclobber=not self.interactive)
return old_names, mirrors
Then I created an extra dict entry in one of my databases entries inside settings.py, 'BYPASS_CREATION':'yes',
Finally, I configured a new TestRunner with
TEST_RUNNER = 'auth.data.runner.ByPassableDBDjangoTestSuiteRunner'
I would suggest using sqlite3 for testing purposes while keeping on using mysql/postgres/etc for production.
This can be achieved by placing this in your settings file:
if 'test' in sys.argv:
DATABASES['default'] = {'ENGINE': 'django.db.backends.sqlite3'}
see Running django tests with sqlite
a temporary sqlite database file will be created in your django project home which you will have write access to. The other advantage is that sqlite3 is much faster for testing. You may however run in to problems if you are using any mysql/postgres specific raw sql (which you should try to avoid anyway).
I think a better solution might be to define your own test runner.
I added this to the comments above but it got kind of lost - recent changes to webfaction make this MUCH easier. You can now create new private database instances.
Follow the instructions there, and when creating a new user make sure to give them the permission to ALTER USER new_username CREATEDB;.
You probably also should change the default cron settings so they don't try to check if this database is up and runnings as frequently.
You could use django-nose as your TEST_RUNNER. Once installed, if you pass the following environment variable, it will not delete and re-create the database (create it manually yourself first).
REUSE_DB=1 ./manage.py test
You can also add the following to settings.py so you don't have to write REUSE_DB=1 every time you want to run tests:
os.environ['REUSE_DB'] = "1"
Note: this will also leave all your tables in the databases which means test setup will be a little quicker, but you will have to manually update the tables (or delete and re-create the database yourself) when you change your models.
my variant to reusing database:
from django.test.simple import DjangoTestSuiteRunner
from django.core.management import call_command
class TestRunner(DjangoTestSuiteRunner):
def setup_databases(self, **kwargs):
from django.db import connections
settings = connections['default'].settings_dict
settings['NAME'] = settings['TEST_NAME']
settings['USER'] = settings['TEST_USER']
settings['PASSWORD'] = settings['TEST_PASSWD']
call_command('syncdb', verbosity=1, interactive=False, load_initial_data=False)
def teardown_databases(self, old_config, **kwargs):
from django.db import connection
cursor = connection.cursor()
cursor.execute('show tables;')
parts = ('DROP TABLE IF EXISTS %s;' % table for (table,) in cursor.fetchall())
sql = 'SET FOREIGN_KEY_CHECKS = 0;\n' + '\n'.join(parts) + 'SET FOREIGN_KEY_CHECKS = 1;\n'
connection.cursor().execute(sql)
The following is a django test suite runner to create database using Webfaction XML-RPC API. Note, setting up the database using the API may take up to a minute, and the script may appear to be stuck momentarily, just wait for a little while.
NOTE: there is a security risk of having control panel password in the webfaction server, because someone breaching into your web server SSH could take over your Webfaction account. If that is a concern, set USE_SESSKEY to True and use the fabric script below this script to pass a session id to the server. The session key expires in 1 hour from the last API call.
File test_runner.py: in the server, you need to configure ./manage.py test to use WebfactionTestRunner
"""
This test runner uses Webfaction XML-RPC API to create and destroy database
"""
# you can put your control panel username and password here.
# NOTE: there is a security risk of having control panel password in
# the webfaction server, because someone breaching into your web server
# SSH could take over your Webfaction account. If that is a concern,
# set USE_SESSKEY to True and use the fabric script below this script to
# generate a session.
USE_SESSKEY = True
# CP_USERNAME = 'webfactionusername' # required if and only if USE_SESSKEY is False
# CP_PASSWORD = 'webfactionpassword' # required if and only if USE_SESSKEY is False
import sys
import os
from django.test.simple import DjangoTestSuiteRunner
from django import db
from webfaction import Webfaction
def get_sesskey():
f = os.path.expanduser("~/sesskey")
sesskey = open(f).read().strip()
os.remove(f)
return sesskey
if USE_SESSKEY:
wf = Webfaction(get_sesskey())
else:
wf = Webfaction()
wf.login(CP_USERNAME, CP_PASSWORD)
def get_db_user_and_type(connection):
db_types = {
'django.db.backends.postgresql_psycopg2': 'postgresql',
'django.db.backends.mysql': 'mysql',
}
return (
connection.settings_dict['USER'],
db_types[connection.settings_dict['ENGINE']],
)
def _create_test_db(self, verbosity, autoclobber):
"""
Internal implementation - creates the test db tables.
"""
test_database_name = self._get_test_db_name()
db_user, db_type = get_db_user_and_type(self.connection)
try:
wf.create_db(db_user, test_database_name, db_type)
except Exception as e:
sys.stderr.write(
"Got an error creating the test database: %s\n" % e)
if not autoclobber:
confirm = raw_input(
"Type 'yes' if you would like to try deleting the test "
"database '%s', or 'no' to cancel: " % test_database_name)
if autoclobber or confirm == 'yes':
try:
if verbosity >= 1:
print("Destroying old test database '%s'..."
% self.connection.alias)
wf.delete_db(test_database_name, db_type)
wf.create_db(db_user, test_database_name, db_type)
except Exception as e:
sys.stderr.write(
"Got an error recreating the test database: %s\n" % e)
sys.exit(2)
else:
print("Tests cancelled.")
sys.exit(1)
db.close_connection()
return test_database_name
def _destroy_test_db(self, test_database_name, verbosity):
"""
Internal implementation - remove the test db tables.
"""
db_user, db_type = get_db_user_and_type(self.connection)
wf.delete_db(test_database_name, db_type)
self.connection.close()
class WebfactionTestRunner(DjangoTestSuiteRunner):
def __init__(self, *args, **kwargs):
# Monkey patch BaseDatabaseCreation with our own version
from django.db.backends.creation import BaseDatabaseCreation
BaseDatabaseCreation._create_test_db = _create_test_db
BaseDatabaseCreation._destroy_test_db = _destroy_test_db
return super(WebfactionTestRunner, self).__init__(*args, **kwargs)
File webfaction.py: this is a thin wrapper for Webfaction API, it need to be importable by both test_runner.py (in the remote server) and the fabfile.py (in the local machine)
import xmlrpclib
class Webfaction(object):
def __init__(self, sesskey=None):
self.connection = xmlrpclib.ServerProxy("https://api.webfaction.com/")
self.sesskey = sesskey
def login(self, username, password):
self.sesskey, _ = self.connection.login(username, password)
def create_db(self, db_user, db_name, db_type):
""" Create a database owned by db_user """
self.connection.create_db(self.sesskey, db_name, db_type, 'unused')
# deletes the default user created by Webfaction API
self.connection.make_user_owner_of_db(self.sesskey, db_user, db_name, db_type)
self.connection.delete_db_user(self.sesskey, db_name, db_type)
def delete_db(self, db_name, db_type):
try:
self.connection.delete_db_user(self.sesskey, db_name, db_type)
except xmlrpclib.Fault as e:
print 'ignored error:', e
try:
self.connection.delete_db(self.sesskey, db_name, db_type)
except xmlrpclib.Fault as e:
print 'ignored error:', e
File fabfile.py: A sample fabric script to generate session key, needed only if USE_SESSKEY=True
from fabric.api import *
from fabric.operations import run, put
from webfaction import Webfaction
import io
env.hosts = ["webfactionusername#webfactionusername.webfactional.com"]
env.password = "webfactionpassword"
def run_test():
wf = Webfaction()
wf.login(env.hosts[0].split('#')[0], env.password)
sesskey_file = '~/sesskey'
sesskey = wf.sesskey
try:
put(io.StringIO(unicode(sesskey)), sesskey_file, mode='0600')
# put your test code here
# e.g. run('DJANGO_SETTINGS_MODULE=settings /path/to/virtualenv/python /path/to/manage.py test --testrunner=test_runner.WebfactionTestRunner')
raise Exception('write your test here')
finally:
run("rm -f %s" % sesskey_file)
The accepted answer didn't work for me. It's so outdated, that it didn't run on my legacy codebase with djano 1.5.
I wrote a blogpost entirely describing how I solved this issue by creating an alternative test runner and changing django settings to provide all the required config and to use new test runner.
You need to specify a sqlite ENGINE when using unit tests. Open the settings.py and add the just after DATABASES section:
import sys
if 'test' in sys.argv or 'test_coverage' in sys.argv: #Covers regular testing and django-coverage
DATABASES['default']['ENGINE'] = 'django.db.backends.sqlite3'
DATABASES['default']['NAME'] = ':memory:'
Modify the following methods in django/db/backends/creation.py:
def _destroy_test_db(self, test_database_name, verbosity):
"Internal implementation - remove the test db tables."
# Remove the test database to clean up after
# ourselves. Connect to the previous database (not the test database)
# to do so, because it's not allowed to delete a database while being
# connected to it.
self._set_test_dict()
cursor = self.connection.cursor()
self.set_autocommit()
time.sleep(1) # To avoid "database is being accessed by other users" errors.
cursor.execute("""SELECT table_name FROM information_schema.tables WHERE table_schema='public'""")
rows = cursor.fetchall()
for row in rows:
try:
print "Dropping table '%s'" % row[0]
cursor.execute('drop table %s cascade ' % row[0])
except:
print "Couldn't drop '%s'" % row[0]
#cursor.execute("DROP DATABASE %s" % self.connection.ops.quote_name(test_database_name))
self.connection.close()
def _create_test_db(self, verbosity, autoclobber):
"Internal implementation - creates the test db tables."
suffix = self.sql_table_creation_suffix()
if self.connection.settings_dict['TEST_NAME']:
test_database_name = self.connection.settings_dict['TEST_NAME']
else:
test_database_name = TEST_DATABASE_PREFIX + self.connection.settings_dict['NAME']
qn = self.connection.ops.quote_name
# Create the test database and connect to it. We need to autocommit
# if the database supports it because PostgreSQL doesn't allow
# CREATE/DROP DATABASE statements within transactions.
self._set_test_dict()
cursor = self.connection.cursor()
self.set_autocommit()
return test_database_name
def _set_test_dict(self):
if "TEST_NAME" in self.connection.settings_dict:
self.connection.settings_dict["NAME"] = self.connection.settings_dict["TEST_NAME"]
if "TEST_USER" in self.connection.settings_dict:
self.connection.settings_dict['USER'] = self.connection.settings_dict["TEST_USER"]
if "TEST_PASSWORD" in self.connection.settings_dict:
self.connection.settings_dict['PASSWORD'] = self.connection.settings_dict["TEST_PASSWORD"]
Seems to work... just add the extra settings to your settings.py if you need 'em.
Simple workaround: change TEST_DATABASE_PREFIX in django/db/backends/base/creation.py as you like.