This page contains guidelines for writing package providers.
One of the most important features of Salt is package management. There is no
shortage of package managers, so in the interest of providing a consistent
experience in pkg
states, there are certain functions
that should be present in a package provider. Note that these are subject to
change as new features are added or existing features are enhanced.
This function should declare an empty dict, and then add packages to it by
calling pkg_resource.add_pkg
, like
so:
__salt__["pkg_resource.add_pkg"](ret, name, version)
The last thing that should be done before returning is to execute
pkg_resource.sort_pkglist
. This
function does not presently do anything to the return dict, but will be used in
future versions of Salt.
__salt__["pkg_resource.sort_pkglist"](ret)
list_pkgs
returns a dictionary of installed packages, with the keys being
the package names and the values being the version installed. Example return
data:
{"foo": "1.2.3-4", "bar": "5.6.7-8"}
Accepts an arbitrary number of arguments. Each argument is a package name. The return value for a package will be an empty string if the package is not found or if the package is up-to-date. The only case in which a non-empty string is returned is if the package is available for new installation (i.e. not already installed) or if there is an upgrade available.
If only one argument was passed, this function return a string, otherwise a dict of name/version pairs is returned.
This function must also accept **kwargs
, in order to receive the
fromrepo
and repo
keyword arguments from pkg states. Where supported,
these arguments should be used to find the install/upgrade candidate in the
specified repository. The fromrepo
kwarg takes precedence over repo
, so
if both of those kwargs are present, the repository specified in fromrepo
should be used. However, if repo
is used instead of fromrepo
, it should
still work, to preserve backwards compatibility with older versions of Salt.
Like latest_version
, accepts an arbitrary number of arguments and
returns a string if a single package name was passed, or a dict of name/value
pairs if more than one was passed. The only difference is that the return
values are the currently-installed versions of whatever packages are passed. If
the package is not installed, an empty string is returned for that package.
Deprecated and destined to be removed. For now, should just do the following:
def myfunc():
return __salt__["pkg.latest_version"](name) != ""
The following arguments are required and should default to None
:
name (for single-package pkg states)
pkgs (for multiple-package pkg states)
sources (for binary package file installation)
The first thing that this function should do is call
pkg_resource.parse_targets
(see below). This function will convert the SLS input into a more easily parsed
data structure.
pkg_resource.parse_targets
may
need to be modified to support your new package provider, as it does things
like parsing package metadata which cannot be done for every package management
system.
pkg_params, pkg_type = __salt__["pkg_resource.parse_targets"](name, pkgs, sources)
Two values will be returned to the install function. The first of them will be a dictionary. The keys of this dictionary will be package names, though the values will differ depending on what kind of installation is being done:
If name was provided (and pkgs was not), then there will
be a single key in the dictionary, and its value will be None
. Once the
data has been returned, if the version keyword argument was
provided, then it should replace the None
value in the dictionary.
If pkgs was provided, then name is ignored, and the
dictionary will contain one entry for each package in the pkgs
list. The values in the dictionary will be None
if a version was not
specified for the package, and the desired version if specified. See the
Multiple Package Installation Options section of the
pkg.installed
state for more info.
If sources was provided, then name is ignored, and the dictionary values will be the path/URI for the package.
The second return value will be a string with two possible values:
repository
or file
. The install function can use this value
(if necessary) to build the proper command to install the targeted package(s).
Both before and after the installing the target(s), you should run
list_pkgs to obtain a list of the installed packages. You should then
return the output of salt.utils.data.compare_dicts()
:
def myfunc():
return salt.utils.data.compare_dicts(old, new)
Removes the passed package and return a list of the packages removed.
There are some functions provided by pkg
which are specific to package
repositories, and not to packages themselves. When writing modules for new
package managers, these functions should be made available as stated below, in
order to provide compatibility with the pkgrepo
state.
All repo functions should accept a basedir option, which defines which directory repository configuration should be found in. The default for this is dictated by the repo manager that is being used, and rarely needs to be changed.
basedir = "/etc/yum.repos.d"
__salt__["pkg.list_repos"](basedir)
Lists the repositories that are currently configured on this system.
__salt__["pkg.list_repos"]()
Returns a dictionary, in the following format:
{'reponame': 'config_key_1': 'config value 1',
'config_key_2': 'config value 2',
'config_key_3': ['list item 1 (when appropriate)',
'list item 2 (when appropriate)]}
Displays all local configuration for a specific repository.
__salt__["pkg.get_repo"](repo="myrepo")
The information is formatted in much the same way as list_repos, but is specific to only one repo.
{'config_key_1': 'config value 1',
'config_key_2': 'config value 2',
'config_key_3': ['list item 1 (when appropriate)',
'list item 2 (when appropriate)]}
Removes the local configuration for a specific repository. Requires a repo argument, which must match the locally configured name. This function returns a string, which informs the user as to whether or not the operation was a success.
__salt__["pkg.del_repo"](repo="myrepo")
Modify the local configuration for one or more option for a configured repo. This is also the way to create new repository configuration on the local system; if a repo is specified which does not yet exist, it will be created.
The options specified for this function are specific to the system; please refer to the documentation for your specific repo manager for specifics.
__salt__["pkg.mod_repo"](repo="myrepo", url="http://myurl.com/repo")
In general, the standard package functions as describes above will meet your needs. These functions use the system's native repo manager (for instance, yum or the apt tools). In most cases, the repo manager is actually separate from the package manager. For instance, yum is usually a front-end for rpm, and apt is usually a front-end for dpkg. When possible, the package functions that use those package managers directly should do so through the low package functions.
It is normal and sane for pkg
to make calls to lowpkgs
, but lowpkg
must never make calls to pkg
. This is affects functions which are required
by both pkg
and lowpkg
, but the technique in pkg
is more performant
than what is available to lowpkg
. When this is the case, the lowpkg
function that requires that technique must still use the lowpkg
version.
Returns a dict of packages installed, including the package name and version. Can accept a list of packages; if none are specified, then all installed packages will be listed.
installed = __salt__["lowpkg.list_pkgs"]("foo", "bar")
Example output:
{"foo": "1.2.3-4", "bar": "5.6.7-8"}
Many (but not all) package management systems provide a way to verify that the files installed by the package manager have or have not changed. This function accepts a list of packages; if none are specified, all packages will be included.
installed = __salt__["lowpkg.verify"]("httpd")
Example output:
{
"/etc/httpd/conf/httpd.conf": {
"mismatch": ["size", "md5sum", "mtime"],
"type": "config",
}
}
Lists all of the files installed by all packages specified. If not packages are specified, then all files for all known packages are returned.
installed = __salt__["lowpkg.file_list"]("httpd", "apache")
This function does not return which files belong to which packages; all files are returned as one giant list (hence the file_list function name. However, This information is still returned inside of a dict, so that it can provide any errors to the user in a sane manner.
{
"errors": ["package apache is not installed"],
"files": ["/etc/httpd", "/etc/httpd/conf", "/etc/httpd/conf.d", "...SNIP..."],
}
Lists all of the files installed by all packages specified. If not packages are specified, then all files for all known packages are returned.
installed = __salt__["lowpkg.file_dict"]("httpd", "apache", "kernel")
Unlike file_list, this function will break down which files belong to which packages. It will also return errors in the same manner as file_list.
{
"errors": ["package apache is not installed"],
"packages": {
"httpd": ["/etc/httpd", "/etc/httpd/conf", "...SNIP..."],
"kernel": [
"/boot/.vmlinuz-2.6.32-279.el6.x86_64.hmac",
"/boot/System.map-2.6.32-279.el6.x86_64",
"...SNIP...",
],
},
}