[Mageia-dev] Bug 2157 - Switch to "standard" rpm metadata for package repositories in Mageia 2

Fri Oct 28 07:42:00 CEST 2011

For whoever wants to discuss:
+
+(In reply to comment #0)
+ > Mageia 2 spec #034
+ > also see https://mageia.org/wiki/doku.php?id=iso2:technical_specification
+ >
+ > Mageia repositories currently have a media_info dir which contains a
+ > line-oriented 'synthesis' file, plus some XML files with additional
+ > information like package descriptions, and a hdlist which AFAIK is not
+ > used by urpmi.
+ >
+ > Fedora and opensuse repositories do not use this format for metadata but
+ > instead have a repodata dir containing a 'primary' and other XML files,
+ > which are all listed in a 'rpomd.xml' file.
+ >
+ > The two schemes are similar which is not very surprising because the
+ > requirements are the same. Most package managers with rpm support can use
+ > the repomd style but urpmi can't. Only a few package managers support
+ > synthesis style metadata. Switching to this 'standard' repository 
+metadata
+ > would give people more choice: use other package managers (e.g. yum 
+or zypper)
+ > in mageia and use urpmi on other distros. In the long term this 
+should help
+ > make urpmi easier to maintain: the "standard" metadata is a bit easier to
+ > extend,
+ > urpmi will be more a standard tool: behavior can easily be compared 
+to other
+ > package managers, test suites may be shared.
+ >
+ > Some not very useful index size numbers for mga cauldron x86_64 
+core/release :
+ > 1.7M    synthesis.hdlist.cz
+ > 1M      info.xml.lzma
+ > 5,6M    changelog.xml.lzma
+ > 8,7M    files.xml.lzma
+ >
+ > 4,4M    primary.xml.gz
+ > 3,4M    other.xml.gz
+ > 11M     filelists.xml.gz (8,8M when compressed with xz)
+ >
+ > Goals:
+ > - no negative impact for people who use the default package tools
+ > - basic support for other package managers (yum, zypper, apt) in mageia 2
+ >   (better support where packagekit uses the package manager the user has
+ >   chosen is not part of this spec but could be a follow-up feature)
+ >
+ > the plan is:
+ > - modify urpmi to only support repomd metadata
+ > - add repomd metadata to the cauldron repository while keeping synthesis
+ > - upload the new urpmi
+ > - after either the mga2 or mga3 release:
+ >   drop synthesis/hdlist metadata from cauldron
+ >
+ > so there will be 1 or 2 stable releases that carry both types of
+ > repository metadata. The build infrastructure needs to support this of
+ > course. This adds some complexity and uses extra space on the mirrors.
+ >
+ > Things that need to be changed:
+ > - urpmi perl code
+ > - maybe a fast xml reader in C, like yum has ?
+ > - rpmdrake/installer ?
+ > - build system
+ >
+ > Open questions:
+ > - Is there anything I missed, unique urpmi features that will be 
+broken by
+ >   such a change, other expected problems?
+ > - A volunteer is needed for writing the needed perl code for 
+perl-URPM etc.,
+ >   otherwise the change won't happen.
+
+a comment here 
+https://mageia.org/wiki/doku.php?do=show&id=iso2%3Atechnical_specification :
+
+sounds interesting but needs to have 2 kinds of metadata in parallel 
+while it's not all integrated - discussions needed
+