Re: RM3694-If database is already connected and click on database then connect database should not displayed in Menu

Hi,

I made the changes to the code such that conn.connect() will happen only
when there is no prior connection exist. In short, connection via context
menu will not trigger this conn.connect().
In the client side code, instead of error alert, info alert is used to
inform the user.

Kindly review the patch and suggest the changes if required.

Thanks,
Sathish V

On Thu, Apr 30, 2020 at 2:43 AM Khushboo Vashi <
khushboo(dot)vashi(at)enterprisedb(dot)com> wrote:

>
>
> On Thu, Apr 30, 2020 at 12:04 PM Aditya Toshniwal <
> aditya(dot)toshniwal(at)enterprisedb(dot)com> wrote:
>
>> Hi,
>>
>> On Thu, Apr 30, 2020 at 11:55 AM Khushboo Vashi <
>> khushboo(dot)vashi(at)enterprisedb(dot)com> wrote:
>>
>>>
>>>
>>> On Thu, Apr 30, 2020 at 10:55 AM Aditya Toshniwal <
>>> aditya(dot)toshniwal(at)enterprisedb(dot)com> wrote:
>>>
>>>> Hi,
>>>>
>>>> On Thu, Apr 30, 2020 at 10:48 AM Khushboo Vashi <
>>>> khushboo(dot)vashi(at)enterprisedb(dot)com> wrote:
>>>>
>>>>>
>>>>>
>>>>> On Thu, Apr 30, 2020 at 10:14 AM Aditya Toshniwal <
>>>>> aditya(dot)toshniwal(at)enterprisedb(dot)com> wrote:
>>>>>
>>>>>> Hi,
>>>>>>
>>>>>>
>>>>>> On Thu, Apr 30, 2020 at 9:41 AM Satish V <satish(dot)v(at)enterprisedb(dot)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(dot)vashi(at)enterprisedb(dot)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(dot)v(at)enterprisedb(dot)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"
>>
>