`meta_package_manager.managers.snap` module¶

class meta_package_manager.managers.snap.Snap[source]¶

Bases: PackageManager

Canonical’s snap installs sandboxed, self-updating packages.

snaps refresh themselves on a schedule, so upgrade merely forces a snap refresh sooner. Mutating operations escalate through sudo by default: the privileged work happens in the snapd daemon, but the daemon refuses state changes from an unprivileged client (snap install as a plain user is denied with a hint to retry with sudo), which is why the Snap store documents sudo snap install as the canonical invocation. A host authenticated against the store with snap login (or granted a polkit rule) can drop the wrap with --no-sudo or a [mpm.overrides.snap] sudo = false override.

Initialize cli_errors list.

operation_notes: ClassVar = {'outdated': 'The `refresh --list` output reports only the available version, so each installed version is looked up separately.', 'search': 'The `snap find` command matches summaries as well as names, so `mpm` refilters the results.'}¶

Per-operation hints rendered in the Notes column of the manager page’s Operations table.

Keyed by the Operations member name, each value is a single short sentence explaining why the manager lacks the operation, or what makes its implementation partial: the pointer a reader needs to judge whether the gap is one they could help close. Each sentence starts with a capital and closes with a period, and starts on a word rather than a code span, so the cell reads standalone beside its row. A blank cell stays silent: a manager documenting nothing documents no gap.

The full rationale never lives here: it belongs in a comment beside the implementing method (or beside this declaration, for an operation with no method to hang it on), so the sentence on the page stays a hint and the code keeps the story. The class docstring follows the same split: it keeps only what a user needs to run the tool day to day, never how mpm wraps it.

Validated by test_operation_notes, which also checks every key matches a real operation: a key outside the enum’s vocabulary would never reach a page.

homepage_url: str | None = 'https://snapcraft.io'¶

Home page of the project, only used in documentation for reference.

Left unset when the home page is the project’s repository, which repository_url names on its own, and when it is the project’s manual, which documentation_url names. Never inherited, like the other links.

documentation_url: str | None = 'https://snapcraft.io/docs/'¶

Entry point of the project’s own documentation, or None when it has none.

The manual, the documentation site, or the man page of the CLI mpm drives: whichever page a user reads to learn the commands this manager wraps. Listed between homepage_url and repository_url in the links of the manager’s page, so a reader reaching for the tool’s reference finds it in the box of facts rather than in the prose below it.

Left unset where a link would state a fact twice or invent one: a tool documenting itself in its repository alone, whose README repository_url already reaches. A page about the ecosystem rather than the tool does not qualify either.

Where a project’s only site is its manual, that address belongs here and homepage_url stays unset: the slot names what the page is, and a reader reaching for the reference looks under the documentation link.

Never inherited, like every other link: the AUR helpers extending pacman each document themselves.

repository_url: str | None = 'https://github.com/canonical/snapd'¶

Repository holding the project’s code, or None when it has no public one.

Linked from the manager’s documentation page. Also what the weekly metrics sample reads: docs/docs_update.py writes it into the [tool.repomatic.metrics] subjects of pyproject.toml when its forge answers the sampler, through a mirror for a forge that does not.

Never inherited, for the same reason as wikipedia_url: the AUR helpers extending pacman each live in a repository of their own.

wikipedia_url: str | None = 'https://en.wikipedia.org/wiki/Snap_(software)'¶

English Wikipedia article about the project, or None when it has none.

Listed last in the links of the manager’s documentation page. The article covers the project that home page names, or is a redirect Wikipedia keeps under the project’s name, landing on the part of a broader article that describes it: Cargo_(software) opens the Cargo section of the Rust article. An article that merely mentions the project does not count, nor does one about a related subject: lazy is a Neovim plugin manager, and the Neovim article is not about it.

Never inherited: the metaclass resets it to None on any class not declaring its own. A subclass often wraps a distinct project, like the six AUR helpers extending pacman, and would otherwise present pacman’s article as its own. Documentation-only, like homepage_url.

logo: str | None = 'snapcraft'¶

Slug of the brand mark standing for this manager in the documentation.

Names an SVG vendored under docs/assets/managers/, whose provenance and license are recorded in docs/assets/managers/logos.yaml. Inlined at the top of the manager’s page by meta_package_manager._docs; a manager leaving it unset keeps the page’s default package glyph.

Several managers legitimately share one slug, either because they wrap the same upstream (brew and cask) or because the tool has no mark of its own and its ecosystem’s stands in (apt under Debian’s swirl, cargo under Rust’s gear). Documentation-only, like homepage_url: no CLI output reads it.

keywords: tuple[str, ...] = ('snapcraft',)¶

Well-known names for this manager that its id does not already carry.

Merged into the PyPI keywords of pyproject.toml by update_keywords() of docs/docs_update.py, alongside every manager ID and the globally curated KEYWORDS_EXTRAS. Declare an alias here rather than in that tuple whenever it names this manager: an alias living beside the class it describes cannot outlive it, where a central entry silently rots once the manager is renamed or dropped.

Reserve KEYWORDS_EXTRAS for terms belonging to no manager in particular, like cyclonedx or package manager. Documentation-only: no CLI output reads it.

Each keyword also becomes a content rule of the issue labeller, so its precision bar applies here: see generate_content_rules(). A subclass inherits the terms of its parent without claiming them, since test_manager_keywords_have_one_owner reads what a class declares itself.

platforms: frozenset[Platform] | Group | Platform | Iterable[Platform | Group] = frozenset({Platform(id='aix', name='IBM AIX'), Platform(id='almalinux', name='AlmaLinux'), Platform(id='alpine', name='Alpine Linux'), Platform(id='altlinux', name='ALT Linux'), Platform(id='amzn', name='Amazon Linux'), Platform(id='android', name='Android'), Platform(id='arch', name='Arch Linux'), Platform(id='buildroot', name='Buildroot'), Platform(id='cachyos', name='CachyOS'), Platform(id='centos', name='CentOS'), Platform(id='chromeos', name='ChromeOS'), Platform(id='clearlinux', name='Clear Linux OS'), Platform(id='cloudlinux', name='CloudLinux OS'), Platform(id='crux', name='CRUX'), Platform(id='cygwin', name='Cygwin'), Platform(id='debian', name='Debian'), Platform(id='dragonfly_bsd', name='DragonFly BSD'), Platform(id='endeavouros', name='EndeavourOS'), Platform(id='exherbo', name='Exherbo Linux'), Platform(id='fedora', name='Fedora'), Platform(id='freebsd', name='FreeBSD'), Platform(id='generic_linux', name='Generic Linux'), Platform(id='gentoo', name='Gentoo Linux'), Platform(id='guix', name='Guix System'), Platform(id='haiku', name='Haiku'), Platform(id='hurd', name='GNU/Hurd'), Platform(id='ibm_powerkvm', name='IBM PowerKVM'), Platform(id='illumos', name='illumos'), Platform(id='kali', name='Kali Linux'), Platform(id='kvmibm', name='KVM for IBM z Systems'), Platform(id='linuxmint', name='Linux Mint'), Platform(id='mageia', name='Mageia'), Platform(id='mandriva', name='Mandriva Linux'), Platform(id='manjaro', name='Manjaro Linux'), Platform(id='midnightbsd', name='MidnightBSD'), Platform(id='netbsd', name='NetBSD'), Platform(id='nixos', name='NixOS'), Platform(id='nobara', name='Nobara'), Platform(id='nutyx', name='NuTyX'), Platform(id='openbsd', name='OpenBSD'), Platform(id='opensuse', name='openSUSE'), Platform(id='openwrt', name='OpenWrt'), Platform(id='oracle', name='Oracle Linux'), Platform(id='os400', name='IBM i'), Platform(id='parallels', name='Parallels'), Platform(id='pidora', name='Pidora'), Platform(id='pikaos', name='PikaOS'), Platform(id='raspbian', name='Raspbian'), Platform(id='rhel', name='RedHat Enterprise Linux'), Platform(id='rocky', name='Rocky Linux'), Platform(id='scientific', name='Scientific Linux'), Platform(id='slackware', name='Slackware'), Platform(id='sles', name='SUSE Linux Enterprise Server'), Platform(id='slitaz', name='SliTaz GNU/Linux'), Platform(id='solaris', name='Solaris'), Platform(id='solus', name='Solus'), Platform(id='sourcemage', name='Source Mage GNU/Linux'), Platform(id='sunos', name='SunOS'), Platform(id='tuxedo', name='Tuxedo OS'), Platform(id='ubuntu', name='Ubuntu'), Platform(id='ultramarine', name='Ultramarine'), Platform(id='void', name='Void Linux'), Platform(id='wsl1', name='Windows Subsystem for Linux v1'), Platform(id='wsl2', name='Windows Subsystem for Linux v2'), Platform(id='xenserver', name='XenServer')})¶

List of platforms supported by the manager.

Allows for a mishmash of platforms and groups of platforms. Will be normalized into a frozenset of Platform instances at instantiation.

default_sudo: bool = True¶

Built-in escalation default, used when sudo is None.

False on the base: most managers install into user-writable trees and never need root. The system package managers whose privileged operations require root (apt, dnf, pacman, zypper, …) set this to True so their build_cli(..., sudo=True) operations escalate out of the box, while staying switchable off through sudo (--no-sudo or config) for rootless setups.

privileged_operations: ClassVar[frozenset[str]] = frozenset({'install', 'remove', 'upgrade', 'upgrade_all'})¶

Operations with at least one command this manager marks privileged.

Keyed by the Operations member name, like operation_notes. An operation belongs here when a method implementing it passes sudo=True to run_cli() or build_cli(), with the method-to-operation map of METHOD_OPERATIONS. Those commands are the only ones the escalation policy (sudo, else default_sudo) wraps in the escalator. A definition derives the set from the operations it marks sudo = true.

prime_sudo() reads it to prompt only for the managers that escalate a command of the current run. With [mpm.overrides.gem] sudo = true, mpm sync asks for no password: the gem sources --update command of sync carries no marker. test_privileged_operations holds the set to the markers in the method bodies.

requirement: str | None = '>=2.0.0'¶

Version requirement specifier.

Supports a comma-separated range of constraints (e.g. ">=1.20.0,<2.0.0"). A bare version string like "1.20.0" is treated as >=1.20.0.

Parsed by meta_package_manager.version.VersionRange.

Defaults to None, which deactivates version check entirely.

post_args: tuple[str, ...] = ('--color=never',)¶

Global list of options used before and after the invoked package manager CLI.

Automatically added to each meta_package_manager.execution.CLIExecutor.run_cli() call.

Essentially used to force silencing, low verbosity or no-color output.

version_regexes: tuple[str, ...] = ('snap\\s+(?P<version>\\S+)',)¶

$ snap --version
snap       2.44.1
snapd      2.44.1
series     16
linuxmint  19.3
kernel     4.15.0-91-generic

property installed: Iterator[Package]¶

Fetch installed packages.

$ snap list --color=never
Name    Version    Rev   Aufzeichnung   Herausgeber     Hinweise
core    16-2.44.1  8935  latest/stable  canonical✓      core
wechat  2.0        7     latest/stable  ubuntu-dawndiy  -
pdftk   2.02-4     9     latest/stable  smoser          -

property outdated: Iterator[Package]¶

Fetch outdated packages.

$ snap refresh --list --color=never
Name            Version  Rev  Herausgeber     Hinweise
standard-notes  3.3.5    8    standardnotes✓  -

search(query, extended, exact)[source]¶

Fetch matching packages.

Caution

Search is extended by default. So we return the best subset of results and let meta_package_manager.manager.PackageManager.refiltered_search() refine them.

$ snap find doc --color=never
Name       Version      Herausgeber  Hinweise  Zusammenfassung
journey    2.14.3       2appstudio   -         Your private diary.
nextcloud  17.0.5snap1  nextcloud✓   -         Nextcloud Server
skype      8.58.0.93    skype✓       classic   One Skype for all.

Return type:: Iterator[Package]

install(package_id, version=None)[source]¶

Install one package.

$ sudo snap install standard-notes --color=never

Return type:: str

upgrade_all_cli()[source]¶

Generates the CLI to upgrade all outdated packages.

$ sudo snap refresh --color=never

Return type:: tuple[str, ...]

upgrade_one_cli(package_id, version=None)[source]¶

Generates the CLI to upgrade the provided package.

$ sudo snap refresh standard-notes --color=never

Return type:: tuple[str, ...]

cli_names: tuple[str, ...] = ('snap',)¶

List of CLI names the package manager is known as.

This list of recognized CLI names is ordered by priority. That way we can influence the search of the right binary.

..hint::: This was helpful in the case of the Python transition from 2.x to 3.x, where multiple versions of the same executable were named python or python3.

By default, this property’s value is derived from the manager’s ID (see the MetaPackageManager.__init__ method above).

id: str = 'snap'¶

Package manager’s ID.

Derived by defaults from the lower-cased class name in which underscores _ are replaced by dashes -.

This ID must be unique among all package manager definitions and lower-case, as they’re used as feature flags for the mpm CLI.

name: str = 'Snap'¶

Return package manager’s common name.

Default value is based on class name.

remove(package_id)[source]¶

Remove one package.

Unlike list, find, refresh and install, snap’s remove subcommand rejects the global --color flag (error: unknown flag ‘color’`). Its output is not parsed, so the``–color=never` post-arg is dropped here with auto_post_args=False.

$ sudo snap remove standard-notes

Return type:: str

virtual: bool = False¶

Should we expose the package manager to the user?

Virtual package manager are just skeleton classes used to factorize code among managers of the same family.

meta_package_manager.managers.snap module¶

`meta_package_manager.managers.snap` module¶