Disable URL-Mangling in BSP Runtime

Question

Hi Experts,
we decided to provide some web applications für mobile devices. Currently (and maybe never) WD ABAP does not support mobile devices. Therefore we are looking for alternatives.
There are a lot of threads in the net where other people discussed the same topic and several decided to use BSP. We wanted to use BSP and jQueryMobile but we noticed that there are some problems because of URL-Mangling / rewriting.
Do you have any idea if it is possible to disable URL-Mangling without modification? We already thought about an own request handler in TA SICF but in this case we also need an own CL_BSP_RUNTIME (to disable the coding in method on_check_rewrite). However this is difficult because some standard BSP runtime classes (RUNTIME, NAVIGATION...) are marked as final, so it isn't possible to inherit from them and we don't want to copy / redevelop all relevant classes.
Furthermore there are other disadvantages like:
- many redirects (problematical with low-bandwidth connections)
- client cookie handling is more difficult
Do you have any idea?
Kind regards
Danny

Answer 1

Hello!
I've done quite a lot of BSP development together with and without javascript frameworks like jQuery. It's possible to create a scenario without URL mangling if you set the system architecture in a specific way. I could speak a lot about this setup as it works really well! Here is a quick guide to get started:
Step 1:
The BSP runtime isn't really used at all. Create a BSP application but only store MIME objects in it. The MIME objects isn't URL mangled! The drawback is of course you can't do server side ABAP in your HTML documents. On the positive side, any Web Developer can create the HTML and javascript without ABAP programming skills. SAP functions as a static web server with all the benefits of the ICM cache and transport system.
Step 2:
Add an external alias in SICF for the BSP application. Like pointing "/myapp" to "/sap/bsp/sap/zmyapp_v001". The external alias is configured with a service account (without any authorizations) with authentication set to "Required with Logon Data". All fields should be specified (Client, User and Language). Now, any anonymous user can request the HTML files without interfering with logon data.
You don't need an external alias, but they come in handy to have nice-looking URLs; the possibility to change their target when you have multiple versions at the same time; and you can create multiple alias for the same application with different logon data. Like "/myapp/english" if you want. Or "/myapp/client800". Or "/myapp/latest", "/myapp/version1" etc.
Step 3:
Create a custom HTTP handler for your business data and assign it to a node in SICF. For example "/customers/orders/get" or whatever you find appropriate for your app. Since you now have your own handler, the BSP runtime isn't involved and no URL mangling exists.
The handler returns data in a suitable format for Web Developers (read: JSON).
Protect this node with security that matches the flexibility required from the frontend. I usually set another service account for this service and handle authorization myself; returning HTTP status codes like 403, 200 to the Web Developer (but not 401 as it's quite difficult to handle in AJAX scenarios). In it's most simple form you can provide username and password as form fields and perform a user switch in the handler for every request, effectively changing SY-UNAME in the handler ensuring that the correct user context is used.
Best regards,
Mikael Gurenius
SAP Solution Architect (Mobility)
PS: MIME objects are of course served with URL Mangling if referenced relative to the BSP application. You can avoid this (for example for the Apple icons) by always linking your MIME objects from the root. Get the application path using code or type manually. Like
  <link rel="apple-touch-icon-precomposed"
sizes="57x57"
href="<%= lv_path %>/icon_57x57.png" /> where lv_path is "/myapp/images" or "/sap/bc/bsp/myapp/images". If you do this, you can have URL Mangling (and do ABAP development) in your BSP pages but still have "clean" URLs for MIME objects.