• Ozan (13/13) Mar 23 2016 Hi
• Adam D. Ruppe (8/10) Mar 23 2016 The way I always did it was to simply have old and new running
• Jesse Phillips (10/23) Mar 23 2016 Do you have an example of this being done in any other language?
• Jacob Carlborg (6/7) Mar 23 2016 In Erlang it's possible to hot swap code. I'm not sure how it works
• Jesse Phillips (5/12) Mar 24 2016 Looks like it is doable because it is byte code:
• cym13 (3/18) Mar 24 2016 It can be done in compiled languages too, here an example of a
• Ozan (2/14) Mar 26 2016 Great link. Thanks for it
• Ozan (12/42) Mar 26 2016 I'm working in SAP area. The main application servers are based
• Chris Wright (8/10) Mar 23 2016 The industry standard is to build on a build server and stop the

Ozan <ozan.sueel gmail.com> writes:

Hi


Enterprise applications in productive environments requires 
smooth updating mechanisms without recompiling or reinstalling. 
It's not possible to stop an enterprise application, then run 
"dub --reforce" and wait until finish. Mostly only few functions 
need to be replaced.

Has someone experience with handling upgrading/updating D-Apps on 
the fly?

Working with dynamic libraries or distributed components is not 
secure enough,
but maybe there are solutions, maybe around base calls and 
functions or completely different.


Regards, Ozan

Adam D. Ruppe <destructionator gmail.com> writes:

On Wednesday, 23 March 2016 at 12:21:33 UTC, Ozan wrote:
 Has someone experience with handling upgrading/updating D-Apps 
 on the fly?

The way I always did it was to simply have old and new running 
side-by-side in the transition.

So, without stopping the old version, compile the new one and 
start it. Tell the web server to start using the new one for all 
new connections without breaking any existing connections.

Then when all existing connections are finished, you can stop the 
old one and remove it.

Jesse Phillips <Jesse.K.Phillips+D gmail.com> writes:

On Wednesday, 23 March 2016 at 12:21:33 UTC, Ozan wrote:
 Hi


 Enterprise applications in productive environments requires 
 smooth updating mechanisms without recompiling or reinstalling. 
 It's not possible to stop an enterprise application, then run 
 "dub --reforce" and wait until finish. Mostly only few 
 functions need to be replaced.

 Has someone experience with handling upgrading/updating D-Apps 
 on the fly?

 Working with dynamic libraries or distributed components is not 
 secure enough,
 but maybe there are solutions, maybe around base calls and 
 functions or completely different.


 Regards, Ozan

Do you have an example of this being done in any other language? 
Essentially whatever code is being replaced, you're going to need 
to recompile it. If you're not using dynamic/shared libraries 
Adam is pointing you in the right direction.

If it is a desktop application then it is probably easiest if it 
communicates to a local service that provides the "replaceable" 
functions, when you stand up the new service the app can transfer 
the communication to it.

I can't speak to your security concerns.

Jacob Carlborg <doob me.com> writes:

On 2016-03-23 18:15, Jesse Phillips wrote:

 Do you have an example of this being done in any other language?

In Erlang it's possible to hot swap code. I'm not sure how it works 
though. But if we're talking servers, the easiest is to have multiple 
instances and restart one at the time with the new code.

-- 
/Jacob Carlborg

Jesse Phillips <Jesse.K.Phillips+D gmail.com> writes:

On Wednesday, 23 March 2016 at 17:29:50 UTC, Jacob Carlborg wrote:
 On 2016-03-23 18:15, Jesse Phillips wrote:

 Do you have an example of this being done in any other 
 language?

 In Erlang it's possible to hot swap code. I'm not sure how it 
 works though. But if we're talking servers, the easiest is to 
 have multiple instances and restart one at the time with the 
 new code.

Looks like it is doable because it is byte code: 
http://erlang.org/doc/reference_manual/code_loading.html#id88478

My recommendation would have been using a DLL, but that was 
already excluded as an option.

cym13 <cpicard openmailbox.org> writes:

On Thursday, 24 March 2016 at 18:46:43 UTC, Jesse Phillips wrote:
 On Wednesday, 23 March 2016 at 17:29:50 UTC, Jacob Carlborg 
 wrote:
 On 2016-03-23 18:15, Jesse Phillips wrote:

 Do you have an example of this being done in any other 
 language?

 In Erlang it's possible to hot swap code. I'm not sure how it 
 works though. But if we're talking servers, the easiest is to 
 have multiple instances and restart one at the time with the 
 new code.

 Looks like it is doable because it is byte code: 
 http://erlang.org/doc/reference_manual/code_loading.html#id88478

 My recommendation would have been using a DLL, but that was 
 already excluded as an option.

It can be done in compiled languages too, here an example of a 
library that allows it in C http://kitsune-dsu.com/

Ozan <ozan.sueel gmail.com> writes:

On Thursday, 24 March 2016 at 23:03:54 UTC, cym13 wrote:
 On Thursday, 24 March 2016 at 18:46:43 UTC, Jesse Phillips 
 wrote:
 On Wednesday, 23 March 2016 at 17:29:50 UTC, Jacob Carlborg 
 wrote:
 On 2016-03-23 18:15, Jesse Phillips wrote:

 Do you have an example of this being done in any other 
 language?




 My recommendation would have been using a DLL, but that was 
 already excluded as an option.

 It can be done in compiled languages too, here an example of a 
 library that allows it in C http://kitsune-dsu.com/

Great link. Thanks for it

Ozan <ozan.sueel gmail.com> writes:

On Wednesday, 23 March 2016 at 17:15:35 UTC, Jesse Phillips wrote:
 On Wednesday, 23 March 2016 at 12:21:33 UTC, Ozan wrote:
 Hi


 Enterprise applications in productive environments requires 
 smooth updating mechanisms without recompiling or 
 reinstalling. It's not possible to stop an enterprise 
 application, then run "dub --reforce" and wait until finish. 
 Mostly only few functions need to be replaced.

 Has someone experience with handling upgrading/updating D-Apps 
 on the fly?

 Working with dynamic libraries or distributed components is 
 not secure enough,
 but maybe there are solutions, maybe around base calls and 
 functions or completely different.


 Regards, Ozan

 Do you have an example of this being done in any other 
 language? Essentially whatever code is being replaced, you're 
 going to need to recompile it. If you're not using 
 dynamic/shared libraries Adam is pointing you in the right 
 direction.

 If it is a desktop application then it is probably easiest if 
 it communicates to a local service that provides the 
 "replaceable" functions, when you stand up the new service the 
 app can transfer the communication to it.

 I can't speak to your security concerns.

I'm working in SAP area. The main application servers are based 
on C++. Every part which is not core could be replaced. 
Applications running in ABAP are also replaceable (thanks to the 
JIT)
There are also solutions in Java. Application Servers are typical 
solutions, where code, libs and apps could be replaced without 
recompiling. Dub is great, but business applications requires 
more the framework or platform approach.
I will try out Martin Nowak's example from DConf. Looks like a 
solution for me...

Regards Ozan

Chris Wright <dhasenan gmail.com> writes:

On Wed, 23 Mar 2016 12:21:33 +0000, Ozan wrote:
 Enterprise applications in productive environments requires smooth
 updating mechanisms without recompiling or reinstalling.

The industry standard is to build on a build server and stop the 
application to update, but to have enough redundancy that users don't see 
any interruption of service. That's how Google and Amazon do it.

There are a bare handful of systems that let you avoid that process. In 
general, it's hard enough for humans to reason about how their 
application's durable state will handle application updates; adding 
volatile state into the picture is much harder, and for little gain.