on 2014/05/21 18:28, Yu Xin Huo wrote:

On 5/21/2014 5:19 PM, Zhou Zheng Sheng wrote:

on 2014/05/21 14:31, Yu Xin Huo wrote:

On 5/21/2014 11:27 AM, Zhou Zheng Sheng wrote:

on 2014/05/21 09:22, Sheldon wrote:

On 05/20/2014 02:53 PM, Yu Xin Huo wrote:

Sample plugin has no difference from other plugins, it is wrong to
specially
design a command for that sample plugin.
A plugin should have a way to disable itself, I prefer the original
way to
disable a plugin like below.

In plugin descriptor xml file, comment out all tabs, if no tabs is
defined,
then the plugin will not be loaded.
By this way, no special command is needed, no additional overhead in
coding is
needed.

@Yu Xin, Your idea of building plugins inside of Kimchi works for the
plugins that comes with Kimchi originally. However usually third-party
plugins should be able to build themselves separately and outside from
kimchi code repository. What Kimchi needs to do is just to discover the
build result of the pluginX and load it, regardless whether it contains
tabs or not.

For example, to compile a Linux kernel module, all we need is some
kernel headers that describe the data structures used by the module
interface. We do not need the kernel source itself. I have a example
kimchi plugin that build outside of kimchi in this way. (We are working
on making it open-source.) After I build the plugin separately, I can
just copy the build result files to kimchi's plugins dir and it loads
automatically.

We also do not enforce all plugins to contain tabs, because some
plugins
can just extend the kimchi API. And the ".conf" file in the specific
plugin dir already contains a "enable = True/False" switch. There is no
need to "comment out all tabs".

Obviously, you mean that there are various types of plugins for kimchi.
If there is a sample for each type of the plugins, no wonder there will
need a command to enable/disable the sample for that type of plugin?

No, we don't need a command to enable the plugins in build time. The
third-party plugins are built without Kimchi code, and outside of Kimchi
source code directory. You can build Kimchi without any plugins then
publish "kimchi.rpm" package. Another developer builds a plugin
separately on a different machine in a different time and publish
"kimchi-pluginX.rpm". The user download all the RPMs and install.

As I said, Kimchi does not provide any plugins, so it does not need to
build any plugins, and we don't need any command to enable the plugins
in build time. All Kimchi knows is that it scans the plugins directory
in runtime and loads all plugins in the directory.

In case a third-party developer want to test his plugin without
generating and installing a RPM file, he can build the plugin
separately, then get Kimchi source code and build Kimchi, copy the
plugin build result to Kimchi source code plugins directory, then at
last run Kimchi from the source code directory.

If I understand you correctly, you mentioned something like ".conf"
which is configuration file for the plugin to enable/disable itself.
I already stated in my previous mail, I prefer a way to get plugin to
enable/disable itself.

You are mixing runtime and build time configurations. The "pluginX.conf"
file is for the runtime. After the a plugin is installed, it is enabled
by default. If the admin want to disable the plugin temporally, he can
edit the "pluginX.conf" file. The build time of the plugins is not
related to the build time of Kimchi.

All the discussion has *nothing* to do with "build time" at all. It is
all about run-time about how kimchi handle plugin.
Please *stop* to get anything about "build time" involved to make things
confusing.

This patch is all about build time configuration. "--enable-plugin-X" is
a switch given to the build scripts. The switch sets the default
availability of a plugin. 

Already stated that, sample are non-production stuff that should never be built into binary delivery package.
So no matter whether you enable/disable the sample plugin, it should be left out from binary delivery package.

If the command itself is only for build time, the command itself should not be shipped in binary delivery package.

For the content of binary delivery, it is determined by the packaging/distribution strategy, it has nothing to do with whether a plugin is enabled or disabled.
A by default disabled plugin can also be shipped in final delivery

The concept to connect "enable/disable plugin" to "the content of build output" itself does not make any sense.
Sample will only be of significance at development time and at run-time.

As regard to runtime configuration, manually
changing "enabled = False/True" is enough. For now the only valid use
case to enable and disable a plugin is that a plugin developer
experimenting some new things on the "sample", and this case is rare. I
think there's little value to add new command for a rare case. Notice
that even the third-party developers do not need to toggle the sample
plugin, and only when we want to extend the plugin framework itself, we
have to enable the sample and test it. So this use case is really rare.

Again, for runtime,

For development, it is ok to modify some config file because it just follow my original design that "plugin should have a way to disable itself".
For production operations, it is not ok for admin to modify the config file, a command is required at runtime to enable/disable plugin which is shipped in binary delivery package.

In all, "--enable-sample" is an acceptable solution for the developer to
toggle the sample plugin occasionally in the developing environment.
It's also acceptable that we don't have any switches or options at all,
and the "enabled = False" is the default in "sample.conf". Whenever the
developer wants to experiment something, just manually edit it and
restart Kimchi back-end server.

Stated above,

For development, no additional command is needed at all, if I understand you correctly, there is already a way for plugin to disable itself.
For the "--enable-sample" command itself, there is no reason to design a command specially for a sample and it need additional handling to leave it out from binary delivery.

Anything that is not target for production(for example, the sample)
should *not* be built into the final binary delivery package.

True, the sample plugin didn't, doesn't and won't be in the binary
package. The switch in this patch is just to toggle its availability
when developer runs Kimchi from source code.

I am a bit confused here.

Here, seems like here you mean that the 'switch' is for run-time.

At the beginning, you said below, the 'switch' is for build time.

This patch is all about build time configuration. "--enable-plugin-X" is
a switch given to the build scripts. The switch sets the default
availability of a plugin.

No matter whether you mean run-time or build-time,
stated above, sample should never be built into binary package, a switch is not needed at all.

For run-time, 2 scenarios, under development  or staged into production
for operations.

As you said, the plugin can be installed separately as a binary package
on top of kimchi installation.
If the admin want to get rid of any installed plugin, he need a way to
disable it.

If the user does not want a plugin, he can just uninstalls it.

For functionality completeness, a plugin can be installed/uninstalled/enabled/disabled like firebug

So there is a need to disable plugin. Either 1 or 2 below is ok.
1. Design a way for plugin to disable itself.
2. Kimchi provide a command to disable/enable any plugin.

@Shaohe, @Yu Xin, as a conclusion, we do not need to add any mechanisms
to define which plugin to build/load. In Kimchi upstream, all the new
features should be added to Kimchi itself, not to plugins. The plugins
are for third-party developers and they should build their plugins
separately. Only the sample plugin that serves as a example on how to
write plugins should be treated specially. So --enable-sample is just
enough, we don't draw the feet of a snake.

Have a command "--enable-sample" specially for a shipped sample in
source distribution is definitely wrong.
There is no justification to have additional overhead in coding for
non-product stuff.

Does that mean the user needs to find this file and uncomment these
codes when
he want to try the plugin.

Usually, a user wants to add a new plugin, he can reference the
sample plugin codes.
He can try it first to how it works and then read the code to how he
can make
himself plugin.

we can change "--enbale-plugins" to "--enable-sample".
our switch command("--enable-sample") is also an example, ti tells
user how he
build a plugin with kimchi
together if he just add one plugin.

Also he can add "with"  command for his plugins if he wants to add
more than one
plugin.
such as:
--with-plugins=plugin1,plugin2,plugin3
The  "with"  command is similar to switch command, a plugin developer
can read
the autotool document to
learn more about it.