I've come across a strange issue on the TechNet forum and thanks to David N Lean, we got an interesting answer. Let me share it here with you.
The project site by default contains the Project Summary webpart which provides to the project team basic project information on the late tasks and tasks to come. It also proposes with a sliding transition the project's timeline, which is also accessible of course in MS Project Pro and in the PWA schedule PDP. So far so good. Here is what does it look like:
|Figure 1: project summary webpart in the project site, displaying the project timeline (on-premise)|
Hester Blok, a skillful Project Server consultant from the Netherlands, came to the forum with the following issue. It was working as expected with Project Server on-premise, but not with Project Online. Here is what she got:
|Figure 2: project summary webpart in the project site, without the project timeline (Online)|
Only the upcoming and late tasks are displayed, but no luck with the sliding timeline... Obviously the timeline is one of the new sexy feature that we do like presenting to customer. The immediate conclusion saying "it is not available with Project Online sites" was neither acceptable technically nor from a customer point of view.
The solution is related to the task list. As you might know, the site tasks list is synchronized with the project tasks and is in read-only mode in the project site. What do I see if I click on a task in the project timeline??
|Figure 3: detail of a task in the site timeline|
The timeline in the site's webpart is built from the site tasks list, not from the schedule timeline itself, nor from the project. Now I share with you a blog post from Brian a few weeks ago. It says:
"The change will make it so that enterprise projects are not synchronized with SharePoint tasks lists, by default. If you still want enterprise projects to synchronize with SharePoint tasks lists, you can turn this setting back on by going to Project Web App (PWA) Settings > Connected SharePoint Sites > Settings, and selecting the ‘Sync Enterprise Projects tasks to Tasks List’ check box."
Thus if you do not change this setting, when you publish first your project, the site is correctly created with the task list, but this list will never get synchronized. That seems to be the root cause why by default, in Project Online, the project summary webpart cannot retrieve the task list information for the timeline.
So just go to the server settings, Operational Policies \ Connected SharePoint Sites and change the setting:
|Figure 4: settings in the connected sharepoint site menu|
|Figure 5: enable the tasks list synchronization|
The thing is that it changes nothing to the existing project site, as far as I could test at least. I tried publishing the project (from PWA only), removing the webpart and adding it again, edit the properties, with no luck... If someone has a trick for this part, please share it, it would be quite tedious to recreate the existing sites, attach them to the projects and migrate the content.
Thus it is quite important that you enable (if applicable to your customer's needs) this parameter while doing the first configuration run of your customer Online instance.