Difference between revisions of "Platform Team/Package Management System"

From Sugar Labs
Jump to navigation Jump to search
m (link update)
 
(128 intermediate revisions by 5 users not shown)
Line 1: Line 1:
<noinclude>{{GoogleTrans-en}}{{TOCright}}
+
== Summary ==
[[Category:Activity Team]]
 
</noinclude>
 
  
== Zero Sugar Distribution ==
+
Sweets is a [http://en.wikipedia.org/wiki/Package_management_system Package Management System] entirely based on [http://0install.net/ Zero Install], a decentralized cross-distribution software installation system. It is intended to distribute various software projects created in the Sugar ecosystem, such as libraries, sugar itself, and sugar activities.
  
Sugar Services provides transparency for users and convenience for activity developers across varying platforms (and their varying dependencies) as well as across Sugar releases. Sugar Services is a method to support this variety of activity dependencies and variety of dependency versions. In other words, Services is a common deployment system for activity dependencies; it is lightweight like [[Development_Team/Sugargame|sugargame]] and like Qt.
+
This new distribution method is initiated with these assumptions:
  
The major difference from existed sugar deployment techniques is that Sugar Services has a point of view of the activity developer. It doesn't exclude (because it reuses them) Sucrose releases or GNU/Linux distribution initiatives, but it does give activity developers an additional (optional) instrument.
+
* The method to share software projects should to be as convenient as possible.
 +
* It is important to stimulate users into becoming doers&mdash;to modify existing activities, and to share the results of their experiments with other people, viz., a distribution method should handle different variants of the same project.
 +
* This distribution method is not intended to be the only one, but is targeted more towards direct distribution&mdash;from software creators to software users.
  
== Workflows ==
+
The goal is to create a new distribution method that goes beyond reusing the current methods:
  
Sugar Services looks different depending upon your point of view:
+
# [[Development_Team/Almanac/Activity_Bundles|''.xo bundles'']]
 +
#* Work smoothly only for pure python activities, though only if all (and the same) dependencies are installed on all systems. They stop working smoothly if activities use non-standard dependencies or contain binaries.
 +
#* But, are not effective in supporting the simultaneous use of multiple versions of software, e.g., the results of experiments (the work) of different doers, in one environment. Users must manually handle the variety of activity versions, e.g., sort out all the local bundles or directories in {{Code|~/Activities}}.
 +
# ''native packages''
 +
#* Are not the shortest way to connect developers with users.
 +
#* In most cases, they don't support multiple versions of the same project.
 +
#* They don't work at all for sharing results of experiments.
  
=== Users ===
+
And, at the same time, the existing distribution methods are available for reuse in Sweets:
  
In the case of a poor Internet connection (and implemented [[Features/Zero_Install_integration|Zero Install integration]] feature), users can switch to offline mode and won't encounter any changes in their regular workflow. Switching to online mode brings additional progress bar to the launch dialog for activities that have pending/not-yet-downloaded/out-dated activity dependencies.
+
# [[Development_Team/Almanac/Activity_Bundles|''.xo bundles'']] are a subset of the Sweets workflow, from the usage point of view.
 +
#* It is possible to bundle an entire directory as a sweet project to use it as a regular .xo file.
 +
# ''native packages''
 +
#* Sweets is not intended to create one more GNU/Linux distribution. It distributes only projects that people create within the Sugar community; all other software, i.e., dependencies, will be reused from native packages.
 +
#* For cases like Sugar deployments, using the more centralized, regular repositories (third party or official GNU/Linux distributions with native packages) makes more sense. These native packages of Sugar software will be included in Sweets, as well. When people start using Sweets on top of these Sugar distributions, they will have the chance to choose between natively packaged Sugar components and components that came directly from software creators.
 +
#* It is possible, when there is a need, to automatically package sweets into native packages. See [[Sweets Distribution]], for example.
  
=== Activity developers ===
+
See also the initial release [[Platform_Team/Sweets/1.0/Notes|notes]].
  
Sugar Services makes sense for activities that have non-Sugar Platform dependencies or support more then one Sucrose release cycle.
+
== Zero Install basis ==
  
For such activities, development focus is shifted from Sucrose to an API of services they are using. More over, an activity could be assigned to particular service API version (provided that service developers still support this branch); Sugar Services will support several branches for the same service simultaneously.
+
Sweets is entirely based on Zero Install. Sweets might be treated as a tools and infrastructure wrapper around Zero Install. See Zero Install's home page, http://0install.net/, for detailed information. And the [http://0install.net/injector-design.html design] page in particular.
  
To utilize the benefits of Services, activity developer need only to [[Activity Team/Documentation/Services/Activity Developers Guide|mention all services (or pure 0install feeds)]] that their activity is using. Services infrastructure will provide specified services (and specified versions) for the activity and will export environment variables, e.g., LD_LIBRARY_PATH or PYTHONPATH, to activity session. ''Activity developer need not to adapt their code to Services.''
+
== Further reading ==
  
=== Use of non-Sugar Platform dependencies in activities ===
+
* [[Platform_Team/Sweets/Architecture|Sweets Architecture]] - A guide to basic Sweets concepts.
 +
* [[Platform_Team/Guide/Sweets_Usage|Sweets Usage]] - A guide to know how to launch software using Sweets.
 +
* [[Platform_Team/Guide/Sweets_Packaging|Sweets Packaging]] - A guide to know how to make your software accessible via Sweets.
 +
* [[Platform_Team/Infrastructure|Infrastructure Map]] - An overview of the Sweets software world.
  
The Sugar Platform cannot grow endlessly and components like Qt or OO4Kids are (at least at present) out of Sugar Platform list. But activities can still use such dependencies by installing them from native packaging systems without bundling binaries. See [[Documentation_Team/Services/Native_packages_usage|Native packages usage]] to know how to utilize native packages in your activity or service.
+
== Getting involved ==
  
=== Service developers ===
+
* Read the [http://git.sugarlabs.org/sdk/sweets/blobs/master/HACKING HACKING] file to know how to contribute with code.
 +
{{:Platform_Team/Sweets/Feedback}}
  
Services could be:
+
== Resources ==
* libraries or applications that are not intended to be included to Sucrose
 
** could be used by few activities
 
** have shorter or longer release/support schedules
 
** just a useful way to share your library w/o bundling binary blobs
 
* dependencies that are specific to particular activity e.g. some python activities have C libraries, using Services, activity developer should not bundle all binaries that sugar supports but provide links to binaries that he managed to build and let Services build C libraries from sources on user side in the rest of cases
 
  
To create new service, developer needs to [[Activity Team/Documentation/Services/Service Developers Guide|create and share]] proper feed which could be used [[Activity Team/Documentation/Services/Activity Developers Guide|by activity developers]].
+
* [http://git.sugarlabs.org/sdk/sweets Sources].
 +
* Recipe files [[Platform_Team/Recipe_Specification|specification]].
  
=== Geeks ===
+
== Subpages ==
  
The entirety of the Sugar Services feature is nothing but a Sugarized UI built around [http://0install.net/ 0install]; i.e., feed files that are being used in activity bundles are just regular 0install local feeds. Services could be used to install/upgrade any software (including sugar core components).
+
{{Special:PrefixIndex/{{PAGENAMEE}}/}}
 
 
== Detailed description ==
 
 
 
This proposal assumes that the core of Sugar development (in common sense) is a wide variety of developers, not just those developers who are taking part in Sugar core (glucose) development. It is all about seeing Sugar activity development from an activity/3rd-party developer's point of view.
 
 
 
From such new core POV, sugar development process will look like:
 
<!-- not sure what you are trying to say here --Walter -->
 
<!-- * see followed "So, .." ~~~~ -->
 
* variety of Sugar activities
 
* that use variety of Sugar Services
 
So, developers use a set of services that have their own API changes based schedules. Glucose could be [[Documentation Team/Services/Native packages usage|wrapped]] to regular service(s) with proper API changes based major versions e.g. if sucrose's activity API wasn't changed since 0.82(sucrose-0.x service) all activities that requires ''sucrose 0'' will be launched but instead of launching activities with requirements ''sucrose 1'', user will be warned about outdated sugar environment.
 
 
 
The corner stone of Sugar Services proposal is [[Activity_Team/Services/Saccharin|Saccharin]] library. This library provides installing/upgrading (via 0install) mechanism for services. The rest of services is just variety of libraries/applications/native-packages. Saccharin could be a part of glucose (some of its releases) or bundled to .xo otherwise.
 
 
 
== FAQ ==
 
 
 
A short list of questions that describe Sugar Services' purposes.
 
 
 
=== What is Sugar Services not? ===
 
 
 
* It is ''not'' intended to cure all ills.
 
* It is ''not'' "must have" for activity developers; use it only if you really [[#Work_flows|need]] it.
 
* Is is ''not'' a replacement for GNU/Linux distributions Sugar packaging efforts; Sugar Services places no need for special treatment regarding dependencies as part of the [[0.86/Platform_Components|Sugar Platform]].
 
* It is ''not'' intended to be used to support large packages (such as Qt or Firefox) in parallel with distributions. Sugar Services should ''not'' be used to avert scenarios such as ''"It is too bad that you don't have Firefox-3.5 in your three-year-old distribution and cannot run last Browse activity."'' In such cases, we should require that users update their distribution and Sugar Platform to more recent versions.
 
 
 
=== How is Sugar Services different? ===
 
 
 
* ''From the point of view of [http://0install.net/ 0install]:'' Sugar Services is just a method to create 0install infrastructure; think about "apt" vs. "dpkg" or "yum" vs. "rpm". In other words, Sugar Services are an analog of [http://0install.net/0release.html 0release] command localized to Sugar needs.
 
 
 
* ''From the point of view of [http://www.packagekit.org/ PackageKit]:'' PackageKit provides a distribution-agnostic method to install already packaged software. Via 0install, Sugar Services let users install unpackaged software as well. More over, 0install will use PackageKit to install missed dependencies if they present in user's distribution.
 
 
 
* ''From the point of view of GNU/Linux distributions'': see the 0install [http://0install.net/goals.html original goals].
 
 
 
== List of services ==
 
 
 
{{Special:PrefixIndex/{{PAGENAME}}/}}
 
 
 
To see entirely list of services, go to http://download.sugarlabs.org/services/.
 
 
 
== Documentation ==
 
 
 
{{Special:PrefixIndex/Documentation_Team/Services/}}
 
 
 
== TODO ==
 
 
 
* [[Activity Team/Services/Bugs|Bugs]] service
 
* install PackageKit from saccharin
 
* [[Activity Team/Services/Statistics|Statistics]] service
 

Latest revision as of 15:51, 3 July 2012

Summary

Sweets is a Package Management System entirely based on Zero Install, a decentralized cross-distribution software installation system. It is intended to distribute various software projects created in the Sugar ecosystem, such as libraries, sugar itself, and sugar activities.

This new distribution method is initiated with these assumptions:

  • The method to share software projects should to be as convenient as possible.
  • It is important to stimulate users into becoming doers—to modify existing activities, and to share the results of their experiments with other people, viz., a distribution method should handle different variants of the same project.
  • This distribution method is not intended to be the only one, but is targeted more towards direct distribution—from software creators to software users.

The goal is to create a new distribution method that goes beyond reusing the current methods:

  1. .xo bundles
    • Work smoothly only for pure python activities, though only if all (and the same) dependencies are installed on all systems. They stop working smoothly if activities use non-standard dependencies or contain binaries.
    • But, are not effective in supporting the simultaneous use of multiple versions of software, e.g., the results of experiments (the work) of different doers, in one environment. Users must manually handle the variety of activity versions, e.g., sort out all the local bundles or directories in ~/Activities.
  2. native packages
    • Are not the shortest way to connect developers with users.
    • In most cases, they don't support multiple versions of the same project.
    • They don't work at all for sharing results of experiments.

And, at the same time, the existing distribution methods are available for reuse in Sweets:

  1. .xo bundles are a subset of the Sweets workflow, from the usage point of view.
    • It is possible to bundle an entire directory as a sweet project to use it as a regular .xo file.
  2. native packages
    • Sweets is not intended to create one more GNU/Linux distribution. It distributes only projects that people create within the Sugar community; all other software, i.e., dependencies, will be reused from native packages.
    • For cases like Sugar deployments, using the more centralized, regular repositories (third party or official GNU/Linux distributions with native packages) makes more sense. These native packages of Sugar software will be included in Sweets, as well. When people start using Sweets on top of these Sugar distributions, they will have the chance to choose between natively packaged Sugar components and components that came directly from software creators.
    • It is possible, when there is a need, to automatically package sweets into native packages. See Sweets Distribution, for example.

See also the initial release notes.

Zero Install basis

Sweets is entirely based on Zero Install. Sweets might be treated as a tools and infrastructure wrapper around Zero Install. See Zero Install's home page, http://0install.net/, for detailed information. And the design page in particular.

Further reading

Getting involved

  • Read the HACKING file to know how to contribute with code.
  • Submit your bug report or feature request.
  • Subscribe to the sugar-devel mailing list and email with the subject prefixed with [SWEETS].
  • Ask your question on IRC channels, #sugar (not logged) or #sugar-newbies (logged).

Resources

Subpages