This would be incredibly complex to resolve and will take too much time at the moment. Disabling / hiding the functionality for now and deferring to a later release.
Proposed solutions:
* Using a more stable method than cms_http_request (probably not possible)
* Using a similar iframe approach as the upgrader and processing each addon one by one, skipping over failed ones (would require passing POST urls and any uploaded data to the iframe; incredibly complex)
* Using an internalised screen to display progress, and process each addon one by one (would still break the process / fail if any one addon throws an error; would require complex changes to forms; would not be reasonable as pre-install info must be displayed)
* Accepting errors everywhere possible via attach_message (would require modifying a lot of functions to support this such as all the addon installing APIs)
* Implementing this in the upgrader instead (not reasonable for non-bundled maintenance)
Narrowed the issue down. The instability is on the server end. FastCGI is prematurely terminating randomly because the addon TAR archives are invalid. Seems Composr's tar script is broken.
Proposed solutions:
* Using a more stable method than cms_http_request (probably not possible)
* Using a similar iframe approach as the upgrader and processing each addon one by one, skipping over failed ones (would require passing POST urls and any uploaded data to the iframe; incredibly complex)
* Using an internalised screen to display progress, and process each addon one by one (would still break the process / fail if any one addon throws an error; would require complex changes to forms; would not be reasonable as pre-install info must be displayed)
* Accepting errors everywhere possible via attach_message (would require modifying a lot of functions to support this such as all the addon installing APIs)
* Implementing this in the upgrader instead (not reasonable for non-bundled maintenance)