In this post I want to share an unusual, nevertheless interesting conceptual idea of loading content from SharePoint 2013 apps on many pages. The original awesome concept was proposed and developed by my colleague Martin Villysson at Bool.
The problem we are trying to solve
SharePoint apps are great to extend functionality in SharePoint and integrate other systems (full page apps available through Site Contents), they also provide tools to enrich the default SharePoint experience by App Parts (Client Web Parts) and Custom Actions (additional menus).
One of the biggest shortcomings of that model is the need to add app parts on all pages where it is needed. Let’s say, we want to have some app parts present on every single page in our whole SharePoint tenancy, to provide a consistent look and feel (e.g. navigation, notifications). Traditionally, on premises, we have added user controls in our customized master page. In SharePoint Online that is impossible. The complicated workaround is to add those client web parts (app parts) on every page, be it manually or by automating it (powershell or app). It will require updating all pages. Nevertheless, it will not work on Out-of-the-box application pages (pages from layouts folder). It becomes even more unacceptable when you realize that your app must be added as an app instance on every single site (SPWeb) in your tenancy.
Towards a solution
After we had created a working Proof-of-Concept of the AppLoader concept, I met Vesa Juvonen at the SharePoint Conference in Las Vegas and introduced this idea to him (although I didn’t call it AppLoader). He liked it although he pointed out that this TenantAppInfo.ashx is an internal utility only in SharePoint and it is not supported by Microsoft. That’s correct. There is even almost no information about it on the Internet. But I got a feeling of Microsoft that they are willing to hear feedback and improve the product. Vesa encouraged me also to blog about it. So now I am telling about this idea. I hope to hear feedback about it. Unfortunately I cannot share the source code of the working Proof-of-Concept solution.
AppLoader Concept in colors
The AppLoader Concept is quite simple. Look at this picture:
The steps in the AppLoader process:
- Make an ajax request to TenantAppInfo.ashx using XHR (XmlHttpRequest)
- Receive the app list
Reading what to render on the page
Usage and Limitations
This bright idea takes advantages from a huge SharePoint API (that contains a lot of good but not supported parts) to make using of apps in Client Application Model solutions more pragmatic and still provide a consistent design and behavior. By consistent design I mean same parts like additional navigation, notifications etc in the whole Intranet. The AppLoader renders and injects whatever you have rolled out to your whole tenancy (Tenant Scoped Apps) and that on every page (!). It also improves the perceived performance of the page load, because it renders app parts (iframes) after the main page has been loaded preventing freezing of the page.
There are of course some limitations in the AppLoader Concept. Today we cannot rely on the TenanAppInfo.ashx API (because it is not supported and future updates can break solutions). We have to define our own custom actions in the apps. That means we can only use our own apps, it will hardly work with the apps installed from the Office Store. On the other hand, your customer will not want to have generic apps from the Office Store to be a part of every page on their intranet.