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path: root/doc/acquire-additional-files.txt
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2016-05-08implement Identifier field for IndexTargetsDavid Kalnischkies
A frontend like apt-file is only interested in a specific set of files and selects those easily via "Created-By". If it supports two locations for those files through it would need to select both and a user would need to know that implementation detail for sources.list configuration. The "Identifier" field is hence introduced which by default has the same value as "Created-By", but can be freely configured – especially it can be used to give two indexes the same identifier.
2016-05-08implement Fallback-Of for IndexTargetsDavid Kalnischkies
Sometimes index files are in different locations in a repository as it is currently the case for Contents files which are per-component in Debian, but aren't in Ubuntu. This has historic reasons and is perhaps changed soon, but such cases of transitions can always happen in the future again, so we should prepare: Introduced is a new field declaring that the current item should only be downloaded if the mentioned item wasn't allowing for transitions without a flagday in clients and archives. This isn't implemented 'simpler' with multiple MetaKeys as items (could) change their descriptions and perhaps also other configuration bits with their location.
2016-01-08keep compressed indexes in a low-cost formatDavid Kalnischkies
Downloading and storing are two different operations were different compression types can be preferred. For downloading we provide the choice via Acquire::CompressionTypes::Order as there is a choice to be made between download size and speed – and limited by whats available in the repository. Storage on the other hand has all compressions currently supported by apt available and to reduce runtime of tools accessing these files the compression type should be a low-cost format in terms of decompression. apt traditionally stores its indexes uncompressed on disk, but has options to keep them compressed. Now that apt downloads additional files we also deal with files which simply can't be stored uncompressed as they are just too big (like Contents for apt-file). Traditionally they are downloaded in a low-cost format (gz) as repositories do not provide other formats, but there might be even lower-cost formats and for download we could introduce higher-cost in the repositories. Downloading an entire index potentially requires recompression to another format, so an update takes potentially longer – but big files are usually updated via pdiffs which has to de- and re-compress anyhow and does it on the fly anyhow, so there is no extra time needed and in general it seems to be benefitial to invest the time in update to save time later on file access.
2015-12-27doc/acquire-additional-files.txt: Mention apt-helper cat-fileJulian Andres Klode
People should know that this is exists.
2015-11-25typo: run s#frontend#front-end# on all of src:aptDavid Kalnischkies
The manpages were fixed by Justin B Rye, lets deal with the rest now. Git-Dch: Ignore
2015-09-14add by-hash sources.list option and document all of by-hashDavid Kalnischkies
This changes the semantics of the option (which is renamed too) to be a yes/no value with the special additional value "force" as this allows by-hash to be disabled even if the repository indicates it would be supported and is more in line with our other yes/no options like pdiff which disable themselves if no support can be detected. The feature wasn't documented so far and hasn't reached a (un)stable release yet, so changing it without trying too hard to keep compatibility seems okay.
2015-08-30implement $(NATIVE_ARCHITECTURE) substvar for indextargetsDavid Kalnischkies
2015-08-29implement indextargets option 'DefaultEnabled'David Kalnischkies
Some targets like Contents-udeb are special-needs targets. Shipping the configuration snippet for them is okay, but they shouldn't be downloaded by default. Forcing the user to enable targets by uncommenting targets is wrong and this would still not really solve the problem completely as even if you want to download some -udebs it will probably not be for all sources you have enabled, so having the possibility of disabling a target by default, but giving the user the option to enable it on a per-source entry basis is better.
2015-08-28implement PDiff patching for compressed filesDavid Kalnischkies
Some additional files like 'Contents' are very big and should therefore kept compressed on the disk, which apt-file did in the past. It also implemented pdiff patching of these files by un- and recompressing these files on-the-fly, with this commit we can do the same – but we can do this in both pdiff patching styles (client and server merging) and secured by hashes. Hashes are in so far slightly complicated as we can't compare the hashes of the compressed files as we might compress them differently than the server would (different compressor versions, options, …), so we must compare the hashes of the uncompressed content. While this commit has changes in public headers, the classes it changes are marked as hidden, so nobody can use them directly, which means the ABI break is internal only.
2015-08-27auto-prefix $(SITE) for indextargets Description fieldDavid Kalnischkies
This updates the documentation for a change which actually happened in c2a4a8dded2dfb56dbcab9689b6cb4b96c9999b6 already. The acquire system expects the $(SITE) to be there (e.g. for mirror rewriting) so we are better of prefixing it automatically than giving frontends the chance to forget it. There is no point in not showing $(SITE) first anyway.
2015-08-27sources.list and indextargets option for pdiffsDavid Kalnischkies
Disabling pdiffs can be useful occasionally, like if you have a fast local mirror where the download doesn't matter, but still want to use it for non-local mirrors. Also, some users might prefer it to only use it for very big indextargets like Contents.
2015-08-10rename 'apt-get files' to 'apt-get indextargets'David Kalnischkies
'files' is a bit too generic as a name for a command usually only used programmatically (if at all) by developers, so instead of "wasting" this generic name for this we use "indextargets" which is actually the name of the datastructure the displayed data is stored in. Along with this rename the config options are renamed accordingly.
2015-06-15implement default apt-get file --release-info modeDavid Kalnischkies
Selecting targets based on the Release they belong to isn't to unrealistic. In fact, it is assumed to be the most used case so it is made the default especially as this allows to bundle another thing we have to be careful with: Filenames and only showing targets we have acquired. Closes: 752702
2015-06-11implement 'apt-get files' to access index targetsDavid Kalnischkies
Downloading additional files is only half the job. We still need a way to allow external tools to know where the files are they requested for download given that we don't want them to choose their own location. 'apt-get files' is our answer to this showing by default in a deb822 format information about each IndexTarget with the potential to filter the records based on lines and an option to change the output format. The command serves also as an example on how to get to this information via libapt.
2015-06-10store all targets data in IndexTarget structDavid Kalnischkies
We still need an API for the targets, so slowly prepare the IndexTargets to let them take this job. Git-Dch: Ignore
2015-06-09configureable acquire targets to download additional filesDavid Kalnischkies
First pass at making the acquire system capable of downloading files based on configuration rather than hardcoded entries. It is now possible to instruct 'deb' and 'deb-src' sources.list lines to download more than just Packages/Translation-* and Sources files. Details on how to do that can be found in the included documentation file.