Re: RM3694-If database is already connected and click on databasethen connect database should not displayed in Menu - Mailing list pgadmin-hackers

On Thu, Apr 30, 2020 at 12:04 PM Aditya Toshniwal <aditya.toshniwal@enterprisedb.com> wrote:

Hi,

On Thu, Apr 30, 2020 at 11:55 AM Khushboo Vashi <khushboo.vashi@enterprisedb.com> wrote:

On Thu, Apr 30, 2020 at 10:55 AM Aditya Toshniwal <aditya.toshniwal@enterprisedb.com> wrote:

Hi,

On Thu, Apr 30, 2020 at 10:48 AM Khushboo Vashi <khushboo.vashi@enterprisedb.com> wrote:

On Thu, Apr 30, 2020 at 10:14 AM Aditya Toshniwal <aditya.toshniwal@enterprisedb.com> wrote:

Hi,

On Thu, Apr 30, 2020 at 9:41 AM Satish V <satish.v@enterprisedb.com> wrote:

Hi Kushboo,

Thanks for the update. I will check the same and make appropriate changes.

Thanks,

Sathish

On Thu, Apr 30, 2020 at 9:20 AM Khushboo Vashi <khushboo.vashi@enterprisedb.com> wrote:

Hi Satish,

As per the RM, the fix is supposed to be at the front-end but it seems difficult at the moment as on the selection of the database, we connect it and at the same time the context menu is being called.

As you have tried to fix at the backend, some of the review comments are below.

1.  If the database is already connected, no need to call conn.connect again.

info_already_connected = conn.connected()

status, errmsg = conn.connect()

I've noticed conn.connected() is misleading sometimes. Let's say if the PG server is stopped and no query is fired from pgadmin after that, then conn.connected() will still give True. It is updated only when a query is fired to the PG server. I would suggest let it connect again as there is no harm and this function is very important. We don't want to mess it up for the sake of a message. 

It's true that conn.connected() is misleading but we already get the connection before checking conn.connected() with conn = manager.connection(did=did, auto_reconnect=True).

So, if the database server is stopped, it will throw the error.

I just checked the manager.connection function, and it is not connecting or checking. It will just give the connection object stored in the memory.

:).

databases/__init__.py : def connect()

manager = get_driver(PG_DEFAULT_DRIVER).connection_manager(sid)

conn = manager.connection(did=did, auto_reconnect=True) 

Above 2 lines will handle which I just just mentioned above.

I didn't find any code which will call the connect, apart from auto_reconnect being used when we execute some query. Nevertheless, I still believe we should not remove the connect call for the sake of a message, for which I think the user won't even bother.

 

To understand the code properly, comment out the line conn.connect() from the def connect(), restart the pgadmin server and try to connect the database from the client side.

So, you get to know that there is no harm in my suggestion.

2. If you want to raise an error at the client side, use the appropriate function or status (check file ajax.py) at the server side and send the appropriate response. 

Below code needs to be changed.

if(res.data.info_already_connected){

  Alertify.error(res.info);

} else {

  Alertify.success(res.info);

}

The problem is test cases. Almost all the test cases have checked for response "Database connected.". If the function is changed at the server side then all the test cases (around 85+) would have to be changed to handle this.

It's a valid point, so I would suggest to show the warning/info at the client side, no need to show the error message.

Yes, info is a good option. 

Thanks,

Khushboo

On Wed, Apr 29, 2020 at 8:20 PM Satish V <satish.v@enterprisedb.com> wrote:

Hi Hackers,

In the patch attached, we are gracefully informing the end user, using an alert message, that the database is already connected when they click "Connect Database..." after right clicking on a disconnected database. 

As this problem deals with racing conditions, it is highly complex to show the "Disconnect database" option in the menu upon right click. So we are alerting the end user with the information of "Database already connected".

Thanks,
Sathish V

--

Thanks and Regards,

Aditya Toshniwal

pgAdmin Hacker | Sr. Software Engineer | EnterpriseDB India | Pune

"Don't Complain about Heat, Plant a TREE"

--

Thanks and Regards,

Aditya Toshniwal

pgAdmin Hacker | Sr. Software Engineer | EnterpriseDB India | Pune

"Don't Complain about Heat, Plant a TREE"

--

Thanks and Regards,

Aditya Toshniwal

pgAdmin Hacker | Sr. Software Engineer | EnterpriseDB India | Pune

"Don't Complain about Heat, Plant a TREE"