The Comprehensive Kerbal Archive Network (CKAN)

This is a Request For Comments on the Comprehensive Kerbal Archive Network (CKAN). Please open discussions in the issues list, and send pull requests to patch this document and associated files.

This document, and all associated files, are licensed under the MIT/Expat license.

The key words "must", "must not", "required", "shall", "shall not", "should", "should not", "recommended", "may" and "optional" in this document are to be interpreted as described in RFC 2119.

Introduction

There have been many comprehensive archive networks for various languages and platforms. While the original network was for TeX (the CTAN), the most successful has been for Perl (the CPAN), with over 11,000 contributors and 30,000 distributions.

The goal of the CKAN is to provide a network that is easy to use for both mod authors and end users. By providing a standardised way to release and install modules, it is hoped that many of the misinstall problems will be eliminated (reducing the workload on authors), and a more straightforward path of installing mods is provided (making it easier for users to use mods).

Design

The fundamental design of the CKAN is as follows:

Each distribution (a mod and its associated files) must have an associated meta-data file that describes its contents.
The meta-data file must be detachable from the distribution itself. This facilities easy building of indexes, and means meta-data can be created independently of the distribution itself, easing adoption by authors.
The meta-data file may be included in the distribution, to facilitate easier indexing. CKAN files may be placed anywhere inside a distribution.
It is an error for a distribution (zipfile) to contain more than one CKAN file.

Presently the authoritative CKAN metadata repository is hosted on github.

Validation

A JSON Schema is provided for validation purposes. Any CKAN file must conform to this schema to be considered valid.

The CKAN file

A CKAN file is designed to contain all the relevant meta-info about a mod, including its name, license, download location, dependencies, compatible versions of KSP, and the like. CKAN files are simply JSON files using UTF-8 as character-encoding.

Except where stated otherwise all strings should be printable unicode only.

CKAN files should have a naming scheme of their mod's identifier, followed by a dash, followed by the version number, followed by the extension .ckan. For example: RealSolarSystem-7.3.ckan.

The CKAN metadata spec is inspired by the CPAN metadata spec, the Debian Policy Manual and the KSP-RealSolarSystem-Bundler

Example CKAN file

{
    "spec_version"   : 1,
    "name"           : "Advanced Jet Engine (AJE)",
    "abstract"       : "Realistic jet engines for KSP",
    "identifier"     : "AJE",
    "download"       : "https://github.com/camlost2/AJE/archive/1.6.zip",
    "license"        : "LGPL-2.1",
    "version"        : "1.6",
    "release_status" : "stable",
    "ksp_version"    : "0.25",
    "resources" : {
        "homepage"     : "http://forum.kerbalspaceprogram.com/threads/70008",
        "repository"   : "https://github.com/camlost2/AJE"
    },
    "tags" : [
        "physics",
        "resources",
        "atmospheric",
        "engines",
        "nasa-enginesim",
        "b9-turbofans"
    ],
    "install" : [
        {
            "file"       : "AJE-1.6",
            "install_to" : "GameData"
        }
    ],
    "depends" : [
        { "name" : "FerramAerospaceResearch" },
        { "name" : "ModuleManager", "min_version" : "2.3.5" }
    ],
    "recommends" : [
        { "name" : "RealFuels" },
        { "name" : "HotRockets" }
    ]
}

Metadata description

The metadata file provides machine-readable information about a distribution.

Mandatory fields

spec_version

The version number of the CKAN specification used to create this .ckan file.

A vx.x string (eg: "v1.2"), being the minimum version of the reference CKAN client that will read this file.

For compatibility with pre-release clients, and the v1.0 client, the special integer 1 should be used.

This document describes the CKAN specification 'v1.20'. Changes since spec 1 are marked with v1.2 through to v1.20 respectively. For maximum compatibility, using older spec versions is preferred when newer features are not required.

name

This is the human readable name of the mod, and may contain any printable characters. Eg: "Ferram Aërospace Research (FAR)", "Real Solar System".

abstract

A short, one line description of the mod and what it does.

identifier

This is the globally unique identifier for the mod, and is how the mod will be referred to by other CKAN documents. It may only consist of ASCII-letters, ASCII-digits and - (dash). Eg: "FAR" or "RealSolarSystem". This is the identifier that will be used whenever the mod is referenced (by depends, conflicts, or elsewhere).

Identifiers must be both: case sensitive for machines, and unique regardless of capitalization for human consumption and case-ignorant systems. Example: MyMod must always be expressed as MyMod, but another module cannot assume the mymod identifier.

If the mod would generate a FOR pass in ModuleManager, then the identifier should be same as the ModuleManager name. For most mods, this means the identifier should be the name of the directory in GameData in which the mod would be installed, or the name of the .dll with any version and the .dll suffix removed.

download

A fully formed URL, indicating where a machine may download the described version of the mod. Note: This field is not required if the kind is metapackage.

license

The license (v1.0), or list of licenses (v1.8), under which the mod is released. The same rules as per the Debian license specification apply, with the following modifications:

The MIT license is always taken to mean the Expat license.
The creative commons licenses are permitted without a version number, indicating the author did not specify which version applies.
Stripping of trailing zeros is not recognised.
(v1.2) WTFPL is recognised as a valid license.
(v1.18) Unlicense is recognised as a valid license.

The following license strings are also valid and indicate other licensing not described above:

open-source: Other Open Source Initiative (OSI) approved license
restricted: Requires special permission from copyright holder
unrestricted: Not an OSI approved license, but not restricted
unknown: License not provided in metadata

A single license (v1.0) , or list of licenses (v1.8) may be provided. The following are both valid, the first describing a mod released under the BSD license, the second under the user's choice of BSD-2-clause or GPL-2.0 licenses.

"license" : "BSD-2-clause"

"license" : [ "BSD-2-clause", "GPL-2.0" ]

If different assets in the mod have different licenses, the most restrictive license should be specified, which may be restricted.

A future version of the spec may provide for per-file licensing declarations.

version

The version of the mod. Versions have the format [epoch:]mod_version.

epoch

epoch is a single (generally small) unsigned integer. It may be omitted, in which case zero is assumed.

It is provided to allow mistakes in the version numbers of older versions of a package, and also a package's previous version numbering schemes, to be left behind.

mod_version

mod_version is the main part of the version number. It is usually the version number of the original mod from which the CKAN file is created. Usually this will be in the same format as that specified by the mod author(s); however, it may need to be reformatted to fit into the package management system's format and comparison scheme.

The comparison behavior of the package management system with respect to the mod_version is described below. The mod_version portion of the version number is mandatory.

While the CKAN will accept any string as a mod_version, mod authors are encouraged to restrict version names to ASCII-letters, ASCII-digits, and the characters . + - _ (full stop, plus, dash, underscore) and should start with a digit.

version ordering

When comparing two version numbers, first the epoch of each are compared, then the mod_version if epoch is equal. epoch is compared numerically. The mod_version part is compared by the package management system using the following algorithm:

The strings are compared from left to right.

First the initial part of each string consisting entirely of non-digit characters is determined. These two parts (one of which may be empty) are compared lexically. If a difference is found it is returned. The lexical comparison is a comparison of ASCII values modified so that all the letters sort earlier than all the non-letters.

Then the initial part of the remainder of each string which consists entirely of digit characters is determined. The numerical values of these two parts are compared, and any difference found is returned as the result of the comparison. For these purposes an empty string (which can only occur at the end of one or both version strings being compared) counts as zero.

These two steps (comparing and removing initial non-digit strings and initial digit strings) are repeated until a difference is found or both strings are exhausted.

Note that the purpose of epochs is to allow us to leave behind mistakes in version numbering, and to cope with situations where the version numbering scheme changes. It is not intended to cope with version numbers containing strings of letters which the package management system cannot interpret (such as ALPHA or pre-), or with silly orderings.

Optional fields

install

A list of install directives for this mod, each must contain exactly one of three source directives:

file: The file or directory root that this directive pertains to. All leading directories are stripped from the start of the filename during install. (Eg: MyMods/KSP/Foo will be installed into GameData/Foo.)
find: (v1.4) Locate the top-most directory which exactly matches the name specified. This is particularly useful when distributions have structures which change based upon each release.
find_regexp: (v1.10) Locate the top-most directory which matches the specified regular expression. This is particularly useful when distributions have structures which change based upon each release, but find cannot be used because multiple directories or files contain the same name. Directories separators will have been normalised to forward-slashes first, and the trailing slash for each directory removed before the regular expression is run. Use sparingly and with caution, it's very easy to match the wrong thing with a regular expression.

In addition a destination directive must be provided:

install_to: The target location where the matched file or directory should be installed.
- Valid values for this entry are GameData, Missions(v1.25), Ships, Ships/SPH(v1.12), Ships/VAB(v1.12), Ships/@thumbs/VAB(v1.16), Ships/@thumbs/SPH(v1.16), Tutorial, Scenarios (v1.14) and GameRoot (which should be used sparingly, if at all).
- A path to a given subfolder location can be specified only under GameData (v1.2); for example: GameData/MyMod/Plugins. The client must check this path and abort the install if any attempts to traverse up directories are found (eg: GameData/../Example).
- Subfolder paths under a matched directory will be preserved, but directories will only be created when installing to GameData, Tutorial, or Scenarios.

In addition, any number of optional directives may be provided:

as : (v1.18) The name to give the matching directory or file when installed. Allows renaming directories or files.
filter : A string, or list of strings, of file parts that should not be installed. These are treated as literal things which must match a file name or directory. Examples of filters may be Thumbs.db, or Source. Filters are considered case-insensitive.
filter_regexp : A string, or list of strings, which are treated as case-sensitive C# regular expressions which are matched against the full paths from the installing zip-file. If a file matches the regular expression, it is not installed.
include_only : (v1.24) A string, or list of strings, of file parts that should be installed. These are treated as literal things which must match a file name or directory. Examples of this may be Settings.cfg, or Plugin. These are considered case-insensitive.
include_only_regexp : (v1.24) A string, or list of strings, which are treated as case-sensitive C# regular expressions which are matched against the full paths from the installing zip-file. If a file matches the regular expression, it is installed.
find_matches_files : (v1.16) If set to true then both find and find_regexp will match files in addition to directories.

If no install sections are provided, a CKAN client must find the top-most directory in the archive that matches the module identifier, and install that with a target of GameData.

A typical install directive only has file and install_to sections:

"install" : [
    {
        "file"       : "GameData/ExampleMod",
        "install_to" : "GameData"
    }
]

comment

A comment field, if included, is ignored. It is not displayed to users, nor used by programs. It's primary use is to convey information to humans examining the CKAN file manually

author

The author, or list of authors, for this mod. No restrictions are placed upon this field.

description

A free form, long text description of the mod, suitable for displaying detailed information about the mod.

release_status

The release status of the mod, one of stable, testing or development, in order of increasing instability. If not specified, a value of stable is assumed.

ksp_version

The version of KSP this mod is targeting. This may be the string "any", a number (eg: 0.23.5) or may only contain the first two parts of the version string (eg: 0.25). In the latter case, any release starting with the ksp_version is considered acceptable.

If no KSP target version is included, a default of "any" is assumed.

ksp_version_min

The minimum version of KSP the mod requires to operate correctly. Same format as ksp_version. It is an error to include both this and the ksp_version field.

ksp_version_max

The maximum version of KSP the mod requires to operate correctly. Same format as ksp_version. It is an error to include both this and the ksp_version field.

ksp_version_strict

(v1.16)

If true, the mod will only be installed if the user's KSP version is exactly targeted by the mod.

If false, the mod will be installed if the KSP version it targets is "generally recognised" as being compatible with the KSP version the user has installed. It is up to the CKAN client to determine what is "generally recognised" as working.

As an example, a mod with a ksp_version of 1.0.3 will also install in KSP 1.0.4 (but not any other version) when ksp_version_strict is false.

This field defaults to false, including for spec_versions less than v1.16, however CKAN clients prior to v1.16 would only perform strict checking.

Relationships

Relationships are optional fields which describe this mod's relationship to other mods. They can be used to ensure that a mod is installed with one of its graphics packs, or two mods which conflicting functionality are not installed at the same time.

At its most basic, this is an array of objects, each being a name and identifier:

"depends" : [
    { "name" : "ModuleManager" },
    { "name" : "RealFuels" },
    { "name" : "RealSolarSystem" }
]

Each relationship is an array of entries, each entry must have a name.

The optional fields min_version, max_version, and version, may more precisely describe which versions are needed:

"depends" : [
    { "name" : "ModuleManager",   "min_version" : "2.1.5" },
    { "name" : "RealSolarSystem", "min_version" : "7.3"   },
    { "name" : "RealFuels" }
]

It is an error to mix version (which specifies an exact version) with either min_version or max_version in the same object.

(v1.0) Clients implementing versions of the spec older than v1.8 must allow for the optional version fields to be present, but may choose to treat them as if they were absent. (v1.8) Clients implementing the v1.8 spec and above must respect the optional version fields if present.

depends

A list of mods which are required for the current mod to operate. This mods must be installed along with the current mod being installed.

recommends

A list of mods which are recommended, but not required, for a typical user. This is a strong recommendation, and recommended mods will be installed unless the user requests otherwise.

suggests

A list of mods which are suggested for installation alongside this mod. This is a weak recommendation, and by default these mods will not be installed unless the user requests otherwise.

supports

(v1.2) A list of mods which are supported by this mod. This means that these mods may not interact or enhance this mod, but they will work correctly with it. These mods should not be installed, this is an informational field only.

conflicts

A list of mods which conflict with this mod. The current mod will not be installed if any of these mods are already on the system.

resources

The resources field describes additional information that a user or program may wish to know about the mod, but which are not required for its installation or indexing. Presently the following fields are described. Unless specified otherwise, these are URLs:

homepage : The preferred landing page for the mod.
bugtracker : The mod's bugtracker if it exists.
license : The mod's license.
repository : The repository where the module source can be found.
ci : (v1.6) Continuous Integration (e.g. Jenkins) Server where the module is being built. x_ci is an alias used in netkan.
spacedock : The mod on SpaceDock.
curse : (v1.20) The mod on Curse.
manual : The mod's manual, if it exists.

Example resources:

"resources" : {
    "homepage"     : "https://tinyurl.com/DogeCoinFlag",
    "bugtracker"   : "https://github.com/pjf/DogeCoinFlag/issues",
    "repository"   : "https://github.com/pjf/DogeCoinFlag",
    "ci"           : "https://ksp.sarbian.com/jenkins/DogecoinFlag"
    "spacedock"    : "https://spacedock.info/mod/269/Dogecoin%20Flag"
    "curse"        : "https://kerbal.curseforge.com/projects/220221"
}

While all currently defined resources are all URLs, future revisions of the spec may provide for more complex types.

It is permissible to have fields prefixed with an x_. These are considered custom use fields, and will be ignored. For example:

"x_twitter" : "https://twitter.com/pjf"

Special use fields

These fields are optional, and should only be used with good reason. Typical mods should not include these special use fields.

kind

Specifies the type of package the .ckan file delivers. This field defaults to package, the other option (and presently the only time the field is explicitly declared) is metapackage. Metapackages allow for a distributable .ckan file that has relationships to other mods while having no download of its own. v1.6

provides

A list of identifiers, that this module provides. This field is intended for use in modules which require one of a selection of texture downloads, or one of a selection of mods which provide equivalent functionality. For example:

"provides"  : [ "RealSolarSystemTextures" ]

It is recommended that this field be used sparingly, as all mods with the same provides string are essentially declaring they can be used interchangeably.

It is considered acceptable to use this field if a mod is renamed, and the old name of the mod is listed in the provides field. This allows for mods to be renamed without updating all other mods which depend upon it.

A module may both provide functionality, and conflict with the same functionality. This allows relationships that ensure only one set of assets are installed. (Eg: CustomBiomesRSS and CustomBiomesKerbal both provide and conflict with CustomBiomesData, ensuring that both cannot be installed at the same time.)

download_size

If supplied, download_size is the number of bytes to expect when downloading from the download URL. It is recommended that this field is only generated by automated tools (where it is encouraged), and not filled in by hand.

download_hash

If supplied, download_hash is an object of hash digests. Currently SHA1 and SHA256 calculated hashes of the resulting file downloaded. It is recommended that this field is only generated by automated tools (where it is encouraged), and not filled in by hand.

"download_hash": {
    "sha1": "1F4B3F21A77D4A302E3417A7C7A24A0B63740FC5",
    "sha256": "E3B0C44298FC1C149AFBF4C8996FB92427AE41E4649B934CA495991B7852B855"
}

download_content_type

If supplied, download_content_type is the content type of the file downloaded from the download URL. It is recommended that this field is only generated by automated tools (where it is encouraged), and not filled in by hand.

"download_content_type": "application/zip"

Extensions

Any field starting with x_ (an x, followed by an underscore) is considered an extension field. The CKAN tool-chain will ignore any such fields. These fields may be used to include additional machine or human-readable data in the files.

For example, one may have an x_maintained_by field, to indicate the maintainer of a CKAN file, or an x_generated_by field to indicate it's the result of a custom build process.

Extension fields are unrestricted, and may contain any sort of data, including lists and objects.

NetKAN Fields

NetKAN is the name the tool which is used to automatically generate CKAN files from a variety of sources. NetKAN consumes .netkan files to produce .ckan files. .netkan files are a strict superset of .ckan files. Every .ckan file is a valid .netkan file but not vice versa. NetKAN uses the following fields to produce .ckan files.

`$kref`

The $kref field indicates that data should be filled in from an external service provider. The following $kref values are understood. Only one $kref field may be present in a .netkan file.

`#/ckan/spacedock/:sdid`

Indicates that data should be fetched from SpaceDock, using the :sdid provided. For example: #/ckan/spacedock/269.

When used, the following fields will be auto-filled if not already present:

name
license
abstract
author
version
download
download_size
download_hash
download_content_type
resources.homepage
resources.spacedock
resources.repository
resources.x_screenshot
ksp_version

`#/ckan/curse/:cid`

Indicates that data should be fetched from Curse, using the :cid provided. For example: #/ckan/curse/220221.

When used, the following fields will be auto-filled if not already present:

name
license
author
version
download
download_size
download_hash
download_content_type
resources.curse
ksp_version

`#/ckan/github/:user/:repo[/asset_match/:filter_regexp]`

Indicates that data should be fetched from GitHub, using the :user and :repo provided. For example: #/ckan/github/pjf/DogeCoinFlag.

When used, the following fields will be auto-filled if not already present:

name
abstract
author
version
download
download_size
download_hash
download_content_type
resources.repository

Optionally, one asset :filter_regexp directive may be provided:

filter_regexp: A string which is treated as case-sensitive C# regular expressions which are matched against the name of the released artifact.

An x_netkan_github field may be provided to customize how the metadata is fetched from GitHub. It is an object with the following fields:

use_source_archive (type: boolean) (default: false)
Specifies that the source ZIP of the repository itself will be used instead of any assets in the release.

`#/ckan/jenkins/:joburl`

Indicates data should be fetched from a Jenkins CI server using the :joburl provided. For example: #/ckan/jenkins/https://jenkins.kspmods.example/job/AwesomeMod/.

The following fields will be auto-filled if not already present:

version
download
download_size
download_hash
download_content_type
resources.ci

An x_netkan_jenkins field may be provided to customize how the metadata is fetched from the Jenkins server. It is an object with the following fields:

build (type: string, enumerated) (default: "stable")
Specifies the type of build to use. Possible values are "any", "completed", "failed", "stable", "successful", "unstable", or "unsuccessful". Many of these values do not make sense to use in practice but are provided for completeness.
asset_match (type: string, regex) (default: "\\.zip$")
Specifies a regex which selects which artifact to use by filename (case-insensitively). Not having exactly one matching asset is an error.
use_filename_version (type: boolean, default: false)
Specifies if the filename of the matched artifact should be used as the value of the version property. Combined with the x_netkan_version_edit property this allows the version to be extracted from the filename itself. Otherwise the expectation is that the archive will have an AVC .version file which will be used to generate the version value.

If any options are not present their default values are used.

An example .netkan excerpt:

{
    "$kref": "#/ckan/jenkins/https://jenkins.kspmods.example/job/AwesomeMod/",
    "x_netkan_jenkins": {
        "build": "stable",
        "asset_match": "\\.zip$",
        "use_filename_version": false
    }
}

`#/ckan/http/:url`

Indicates data should be fetched from a HTTP server, using the :url provided. For example: #/ckan/http/https://ksp.marce.at/Home/DownloadMod?modId=2.

When used, the following fields will be auto-filled if not already present:

download
download_size
download_hash
download_content_type

This method depends on the existence of an AVC .version file in the download file to determine:

version

`#/ckan/netkan/:url`

Indicates that data should be fetched from another .netkan file hosted remotely. For example: #/ckan/netkan/https://www.kspmods.example/AwesomeMod.netkan.

The remote .netkan file is downloaded and used as if it were the original. .netkan files which contain such a reference are known as recursive netkans or metanetkans. They are primarily used so that mod authors can provide authoritative metadata.

The following conditions apply:

A metanekan may not reference another metanetkan, otherwise an error is produced.
Any fields specified in the metanetkan will override any fields in the target netkan file.

An example .netkan including all required fields for a valid metanetkan:

{
    "spec_version": 1,
    "identifier": "AwesomeMod",
    "$kref": "#/ckan/netkan/https://www.kspmods.example/AwesomeMod.netkan"
}

`$vref`

The $vref field indicates that version data should be filled in from an external service provider. Only one $vref field may be present in a document.

`#/ckan/ksp-avc[[/path]/avcfilename.version]`

If present, a $vref symbol of #/ckan/ksp-avc states that version information should be retrieved from an embedded KSP-AVC .version file in the file downloaded by the download field. The following conditions apply:

Only .version files that would be installed for this mod are considered. (In theory. Transformer ordering may cause files outside the installed folders being considered)
It is an error if more than one .version file would be considered.
It is an error if the .version file does not validate according to the KSP-AVC spec.
The KSP_VERSION field for the .version file will be ignored if the KSP_VERSION_MIN and KSP_VERSION_MAX fields are set.
Netkan will first attempt to use anything after ksp-avc as a literal path within the zip file, and if that fails, will use the string as a regexp to search for a matching file to use.

When used, the following fields are auto-generated:

ksp_version
ksp_version_min
ksp_version_max

Version information is generated in such a way as to ensure maximum compatibility. For example if the .version file specifies that the mod is compatible with KSP version 1.0.2 but the existing version specifies 1.0.5 then the version information generated will give a ksp_version_min of 1.0.2 and a ksp_version_max of 1.0.5.

If (and only if) no mod version number has been identified (eg a #/ckan/http/:url), then the following field will also be auto-generated:

version

`x_netkan_epoch`

The x_netkan_epoch field is used to specify a particular epoch number in the version field. Its value should be an unsigned 32-bit integer.

An example .netkan excerpt:

{
    "x_netkan_epoch": 1
}

`x_netkan_force_v`

The x_netkan_force_v field is used to specify that a v should be prepended to the version field. It is a boolean field.

A combination of x_netkan_epoch and x_netkan_version_edit should be used instead to ensure that the version field only contains the actual version string.

An example .netkan excerpt:

{
    "x_netkan_force_v": true
}

`x_netkan_version_edit`

The x_netkan_version_edit field is used to edit the final value of the version field. x_netkan_version_edit is an object with the following fields:

find (type: string, regex) (default: none)
A regex to match against the existing version field.
replace (type: string, regex substitution) (default: "${version}")
Specifies a regex substitution string which will be used as the value of the new version field.
strict (type: boolean, default: true)
Specifies if NetKAN should produce an error if find fails to produce a match against the version field.

x_netkan_version_edit can also be a string in which case its value is treated as the value the find field and the default values for the replace and strict fields are used.

An example .netkan excerpt:

{
    "$kref": "#/ckan/jenkins/https://jenkins.kspmods.example/job/AwesomeMod/",
    "x_netkan_version_edit": {
        "find": "^[vV]?(?<version>.+)$",
        "replace": "${version}",
        "strict": true
    }
}

`x_netkan_override`

The x_netkan_override field is used to override field values based on the value of the version field. x_netkan_override is an array of objects. Each object may have the following fields:

version (type: array of string, version comparison)
An array of version comparison strings that are used to match against version. Version comparison strings are of the form "[operator]<version>" where operator is one of =, <, >, <=, or >=. If no operator is given it is equivalent to specifying =. In order for the override to match all the comparisons must be true. Therefore a range may be specified as such: [ ">=1.0", "<2.0" ]. A string may also be specified instead of an array in which case it is treated as an array with a single element equal to the value of the string.
before (type: string, transformation name)
The name of a transformation this override to happen directly before.
after (type: `string:, transformation name)
The name of a transformation this override to happen directly after.
override (type: object)
An object whose fields will override the fields already present if a match occurs. No merging of values occurs, the values of the fields are entirely replaced.
delete (type: array of string)
An array of strings which are the names of fields to remove if a match occurs.

The possible values of before and after are:

$none
$all
avc
download_attributes
epoch
forced_v
generated_by
github
http
internal_ckan
jenkins
metanetkan
optimus_prime
property_sort
spacedock
curse
strip_netkan_metadata
version_edit
versioned_override

If no before or after is specified then the override occurs at a "reasonable" point in the transformation process. Most overrides should not specify a before or after unless there is a specific need to.

When any metadata changes occur which are version specific, for example a new dependency is added, overrides are the recommended means of specifying them. Overrides may also be used to stage metadata changes, for example when new dependencies are anticipated to be added in yet unreleased versions of a mod. This allows mod metadata to be up-to-date as soon as possible without requiring excessive coordination.

Files

Spec.md

Latest commit

History

Spec.md

File metadata and controls

The Comprehensive Kerbal Archive Network (CKAN)

Introduction

Design

Validation

The CKAN file

Example CKAN file

Metadata description

Mandatory fields

spec_version

name

abstract

identifier

download

license

version

epoch

mod_version

version ordering

Optional fields

install

comment

author

description

release_status

ksp_version

ksp_version_min

ksp_version_max

ksp_version_strict

tags

Relationships

depends

recommends

suggests

supports

conflicts

resources

Special use fields

kind

provides

download_size

download_hash

download_content_type

Extensions

NetKAN Fields

$kref

#/ckan/spacedock/:sdid

#/ckan/curse/:cid

#/ckan/github/:user/:repo[/asset_match/:filter_regexp]

#/ckan/jenkins/:joburl

#/ckan/http/:url

#/ckan/netkan/:url

$vref

#/ckan/ksp-avc[[/path]/avcfilename.version]

x_netkan_epoch

x_netkan_force_v

x_netkan_version_edit

x_netkan_override

`$kref`

`#/ckan/spacedock/:sdid`

`#/ckan/curse/:cid`

`#/ckan/github/:user/:repo[/asset_match/:filter_regexp]`

`#/ckan/jenkins/:joburl`

`#/ckan/http/:url`

`#/ckan/netkan/:url`

`$vref`

`#/ckan/ksp-avc[[/path]/avcfilename.version]`

`x_netkan_epoch`

`x_netkan_force_v`

`x_netkan_version_edit`

`x_netkan_override`