Shall I resend session scope custom dimension after session timeouts?

[Sollll]

Hi. A question about sessions and custom dimension.
On google docs I read:

By default, a session lasts until there's 30 minutes of inactivity

My custom dimension has session scope.
So the question is - shall I set my custom dimension with window.ga.addCustomDimension() after each 30 minutes of inactivity?

[victorsosa]

No, the customDimension will be set permanently. But it will count one every session.

[Sollll]

@victorsosa Thanks for quick reply! :)

1. So, if I don't want to have old value on the new session(which starts after timeout or manually) then I shall set custom dimension to '' or some new value?
2. After application restart will it be clean or have value from last time?

[victorsosa]

1. you can do it manually by creation a new session. check the readme about it.

//To track a Screen (PageView) and create a new session:
window.ga.trackView('Screen Title', '', true)

2. clean, the value that you set.

[Sollll]

1a. So creating new session via trackView or trackEvent will reset all custom dimensions?
1b. As opposite - when new sessions created because of timeout it does not reset dimensions?

[Sollll]

@victorsosa I tried to test it...

window.ga.addCustomDimension(1, 'testSessionsDimension')
window.ga.trackView('testSessionsView1')
window.ga.trackEvent('testSessionsEvent1', 'testSessionsEvent1', 'testSessionsEvent1')
event onPause 
... here I left my tablet for 40+ minutes to get automatic session start
event onResume 
window.ga.trackView('testSessionsView2')
window.ga.trackEvent('testSessionsEvent2', 'testSessionsEvent2', 'testSessionsEvent2')
event onPause 
event onResume
window.ga.dispatch()
window.ga.trackEvent('testSessionsEvent3', 'testSessionsEvent3', 'testSessionsEvent3',0,true)
window.ga.trackView('testSessionsView3')
window.ga.dispatch()
... Then I restarted application and entered
window.ga.trackView('testSessionsView4')
window.ga.trackEvent('testSessionsView4', 'testSessionsView4', 'testSessionsView4')

And in ga all screens have dimension set to testSessionsDimension... even after application restart.
Why is it this way?

[victorsosa]

Do you want to use another dimension or reset the dimension?
use another dimension: window.ga.addCustomDimension(2, 'testSessionsDimension2')
reset: window.ga.addCustomDimension(1, '')

[Sollll]

@victorsosa
I want to understand - if I set value to dimension that has session scope, when it will be reset?
As I understand from ga docs, it should apply only to current ga session! Thats the point of session scope...
Will it be reset on:

1. Application restart? You told me that after restart it would be clean, but somehow ga shows me that it is still set.. - check my previous post - testSessionsView4 should not have testSessionsDimension value...
2. Session timeout (as I understand it should be reset on timeout, because it was set only for current session(session scope param))?
3. Manual start of new session(using trackEvent and trackView with last parameter true)?

[victorsosa]

plase check comment on #415; there is a bug with this.

[spacepope]

I added PR #443 to provide the possibility to unset custom dimensions and metrics.

@Sollll to understand how this plugin works (on Android and Windows) with custom dimensions and metrics: on every call to addCustomDimension or trackMetric an entry is added to an internal dictionary. Then on every call to trackView, trackEvent, trackException, etc.. all custom dimensions and metrics are added to the hit via HitBuilder classes and sent to Analytics.
As far as i know Google Analytics Backend then computes the dimensions and metrics on behalf of your scope settings (Hit, Session, Product, ...). If you want to know more, read the Google Analytics Docs for Android

So if i get it right: if you selected Session scope for your dimension, it should only be unset (at the analytics backend) by starting a new session, which as @victorsosa pointed out is possible by tracking a view with third parameter set to true.
(Additionally you would have to unset the custom dimension / metric, otherwise it is added again to the next hit sent... Thats why i submitted a PR..)

I never did so much custom dimensions / metrics and just transcribed the Android algorithm to Windows platform.
But, @victorsosa, perhaps the Android behaviour on this was not the right way of handling this before..
Look at the iOS implementation for trackMetric: there the metric is set directly on the tracker object with [tracker set:[GAIFields customMetricForIndex:[key intValue]] value:value];, no internal dictionary. But thats not consistent as a dictionary is used for custom dimensions and added on every hit tracked like on Android - why is it that way?

In the setup pages for custom dimensions and metrics google proposes the following code snippets for
Browser:

var dimensionValue = 'SOME_DIMENSION_VALUE';
ga('set', 'dimension1', dimensionValue);

var metricValue = '123';
ga('set', 'metric1', metricValue);

Android:

String dimensionValue = "SOME_DIMENSION_VALUE";
tracker.set(Fields.customDimension(1), dimensionValue);

String metricValue = SOME_METRIC_VALUE_SUCH_AS_123_AS_STRING;
tracker.set(Fields.customMetric(1), metricValue);

and iOS:

NSString *dimensionValue = @"SOME_DIMENSION_VALUE";
[tracker set:[GAIFields customDimensionForIndex:1] value:dimensionValue];

NSString *metricValue = SOME_METRIC_VALUE_SUCH_AS_123_AS_STRING;
[tracker set:[GAIFields customMetricForIndex:1] value:metricValue];

Furthermore it is stated that custom dimensions and metrics only have to be sent once.

Could it be, that we potentially can get rid of all the internal dictionary stuff and do it this way on all platforms?

[victorsosa]

iOS implementation use dictionary too.

Could it be, that we potentially can get rid of all the internal dictionary stuff and do it this way on all platforms?
NO

You should do the same implementation for all platforms in the PR #443; no just Android