Thread: RM#3294 - User need to reset the layout to see the changedpreferences parameters

Hi Hackers,

This is regarding RM3294 which I am working on, where user needs to reset the layout to see the changed preferences parameters. I am able to implement it, and have used the following approach:

1) when preference changed, fire a custom event - prefChangedEvent

2) listent to prefChangedEvent wherever preferences should be reflected in realtime.

3) In the event handler, make the changes as per the module.

4) So whenever the preferences are changed, the event fires, the listener executes the event handler and changes are done.

Benefit of this approach is no polling. But, there is a problem here. 

It is not possible to fire event in another tab/new browser window. For example, query tool can be open in another tab. And thus, changes are not reflected there. There are solutions available like updating the localStorage of the browser but those are not reliable and does not work properly on different browsers.

Request you to kindly suggest if you any better idea.

Thanks and Regards,

Aditya Toshniwal

Software Engineer | EnterpriseDB Software Solutions | Pune

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

On Mon, Jun 11, 2018 at 6:02 PM, Aditya Toshniwal <aditya.toshniwal@enterprisedb.com> wrote:

Hi Hackers,

This is regarding RM3294 which I am working on, where user needs to reset the layout to see the changed preferences parameters. I am able to implement it, and have used the following approach:

1) when preference changed, fire a custom event - prefChangedEvent

We can also fire preference specific event instead of generic event.

And we can generate event name from preference itself like <module>:<category>:<name>:<event_type>

eg.: browser:display:show_system_objects:update 

 

2) listent to prefChangedEvent wherever preferences should be reflected in realtime.

3) In the event handler, make the changes as per the module.

4) So whenever the preferences are changed, the event fires, the listener executes the event handler and changes are done.

Benefit of this approach is no polling. But, there is a problem here. 

It is not possible to fire event in another tab/new browser window. For example, query tool can be open in another tab. And thus, changes are not reflected there. There are solutions available like updating the localStorage of the browser but those are not reliable and does not work properly on different browsers.

To communicate between browser tabs we can use cookie polling on client side it self (at least it will avoid polling over http).

The main tab will update only preference specific cookie when preference is updated and other tabs will poll required cookies (not all)

with specific interval (1 second can be configurable).

 

Request you to kindly suggest if you any better idea.

Thanks and Regards,

Aditya Toshniwal

Software Engineer | EnterpriseDB Software Solutions | Pune

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

Hi Aditya,

It is not possible to fire event in another tab/new browser window. For example, query tool can be open in another tab. And thus, changes are not reflected there. There are solutions available like updating the localStorage of the browser but those are not reliable and does not work properly on different browsers.

To communicate between browser tabs we can use cookie polling on client side it self (at least it will avoid polling over http).

The main tab will update only preference specific cookie when preference is updated and other tabs will poll required cookies (not all)

with specific interval (1 second can be configurable).

Polling is a solution but I think it should be the last option. http polls will not be required anyway as we have preference cache in the browser object.

 

Maybe it's better to poll only when an editor is open in a separate window?  What would we be polling for and how would be tell the backend that something changed during the poll?

Thanks

Victoria & Joao

Hi Victoria/Hackers,

On Tue, Jun 12, 2018 at 9:52 PM, Victoria Henry <vhenry@pivotal.io> wrote:

Hi Aditya,

It is not possible to fire event in another tab/new browser window. For example, query tool can be open in another tab. And thus, changes are not reflected there. There are solutions available like updating the localStorage of the browser but those are not reliable and does not work properly on different browsers.

To communicate between browser tabs we can use cookie polling on client side it self (at least it will avoid polling over http).

The main tab will update only preference specific cookie when preference is updated and other tabs will poll required cookies (not all)

with specific interval (1 second can be configurable).

Polling is a solution but I think it should be the last option. http polls will not be required anyway as we have preference cache in the browser object.

 

Maybe it's better to poll only when an editor is open in a separate window?  What would we be polling for and how would be tell the backend that something changed during the poll?

 

​Currently I am using the cache_preferences function to fire the events.​ cache_preferences is called whenever preferences are changed. I suggest we add kind of version for the preference cache, lets say prefcache_version and we can set it to current epoch time whenever the cache_preference is called.

​

​ Now, when a new tab/window is opened, it will store the version of prefcache it is having. When the main window changes the preferences and cache_preference is called, the prefcache_version will increase to current epoch time. New tab polling can check if the version has increased and can update ​its preferences along with prefcache_version.

​Please let me know if any suggestions.​

Thanks

Victoria & Joao

--

Thanks and Regards,

Aditya Toshniwal

Software Engineer | EnterpriseDB Software Solutions | Pune

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