Add Pacman module

pasch/__init__.py

@@ -1,5 +1,5 @@
 from . import modules
-from .cmd import run_capture, run_check
+from .cmd import run_capture, run_execute
 from .orchestrator import Module, Orchestrator
 
 __all__: list[str] = [
@@ -7,5 +7,5 @@ __all__: list[str] = [
     "Orchestrator",
     "modules",
     "run_capture",
-    "run_check",
+    "run_execute",
 ]

pasch/cmd.py

@@ -5,12 +5,12 @@ from rich import print
 from rich.markup import escape
 
 
-def run_check(*cmd: str) -> None:
+def run_execute(*cmd: str) -> None:
     print(f"[bright_black]$ {escape(shlex.join(cmd))}")
     subprocess.run(cmd, check=True)
 
 
 def run_capture(*cmd: str) -> str:
-    print(f"[bright_black]$ {escape(shlex.join(cmd))}")
+    print(f"[bright_black italic]$ {escape(shlex.join(cmd))}")
     result = subprocess.run(cmd, check=True, capture_output=True, encoding="utf-8")
     return result.stdout

pasch/modules/__init__.py

@@ -1,5 +1,7 @@
 from .echo import Echo
+from .pacman import Pacman
 
 __all__: list[str] = [
     "Echo",
+    "Pacman",
 ]

pasch/modules/echo.py

@@ -1,4 +1,4 @@
-from pasch.cmd import run_check
+from pasch.cmd import run_execute
 from pasch.orchestrator import Module, Orchestrator
 
 
@@ -11,4 +11,4 @@ class Echo(Module):
         self.args.append(arg)
 
     def realize(self) -> None:
-        run_check("echo", *self.args)
+        run_execute("echo", *self.args)

pasch/modules/pacman.py

@@ -0,0 +1,98 @@
+from dataclasses import dataclass, field
+
+from rich import print
+from rich.markup import escape
+
+from pasch.cmd import run_capture, run_execute
+from pasch.orchestrator import Module, Orchestrator
+
+
+@dataclass
+class PacmanPackage:
+    name: str
+    exclude: set[str] = field(default_factory=set)
+
+
+class Pacman(Module):
+    def __init__(self, orchestrator: Orchestrator) -> None:
+        super().__init__(orchestrator)
+        self.binary: str = "pacman"
+        self.packages: set[str] = set()
+        self.excluded: dict[str, set[str]] = {}
+
+    def install(self, *packages: str) -> None:
+        self.packages.update(packages)
+
+    def exclude(self, group: str, *packages: str) -> None:
+        self.excluded.setdefault(group, set()).update(packages)
+
+    def realize(self) -> None:
+        groups = self._get_groups()
+
+        installed = self._get_explicitly_installed_packages()
+        target = self._resolve_packages(groups, self.packages)
+
+        to_install = target - installed
+        to_uninstall = installed - target
+
+        for package in sorted(to_install):
+            print(f"[bold green]+[/] {escape(package)}")
+        for package in sorted(to_uninstall):
+            print(f"[bold red]-[/] {escape(package)}")
+
+        self._install_packages(to_install)
+        self._uninstall_packages(to_uninstall)
+
+    def _pacman_capture(self, *args: str) -> str:
+        return run_capture(self.binary, *args)
+
+    def _pacman_execute(self, *args: str) -> None:
+        if self.binary == "paru":
+            run_execute(self.binary, *args)  # Calls sudo itself
+        else:
+            run_execute("sudo", self.binary, *args)
+
+    def _get_explicitly_installed_packages(self) -> set[str]:
+        return set(self._pacman_capture("-Qqe").splitlines())
+
+    def _get_groups(self) -> dict[str, set[str]]:
+        groups = {}
+        for line in self._pacman_capture("-Sgg").splitlines():
+            group, package = line.split(" ", maxsplit=1)
+            groups.setdefault(group, set()).add(package)
+        return groups
+
+    def _resolve_packages(
+        self,
+        groups: dict[str, set[str]],
+        packages: set[str],
+    ) -> set[str]:
+        result = set()
+        for package in packages:
+            result.update(self._resolve_package(groups, package))
+        return result
+
+    def _resolve_package(self, groups: dict[str, set[str]], package: str) -> set[str]:
+        packages = groups.get(package)
+        if packages is None:
+            return {package}
+        packages = packages - self.excluded.get(package, set())
+        return self._resolve_packages(groups, packages)
+
+    def _install_packages(self, packages: set[str]) -> None:
+        if self.orchestrator.dry_run:
+            return
+        if not packages:
+            return
+
+        self._pacman_execute("-S", "--needed", *sorted(packages))
+        self._pacman_execute("-D", "--asexplicit", *sorted(packages))
+
+    def _uninstall_packages(self, packages: set[str]) -> None:
+        if self.orchestrator.dry_run:
+            return
+        if not packages:
+            return
+
+        self._pacman_execute("-D", "--asdeps", *sorted(packages))
+        self._pacman_execute("-Rsn", *self._pacman_capture("-Qqdt").splitlines())

pasch/orchestrator.py

@@ -2,6 +2,9 @@ from __future__ import annotations
 
 from abc import ABC, abstractmethod
 
+from rich import print
+from rich.markup import escape
+
 
 class Module(ABC):
     def __init__(self, orchestrator: Orchestrator) -> None:
@@ -13,16 +16,19 @@ class Module(ABC):
 
 
 class Orchestrator:
-    def __init__(self) -> None:
+    def __init__(self, dry_run: bool = False) -> None:
-        self.frozen: bool = False
+        self.dry_run = dry_run
-        self.modules: list[Module] = []
+
+        self._frozen: bool = False
+        self._modules: list[Module] = []
 
     def register(self, module: Module) -> None:
-        if self.frozen:
+        if self._frozen:
             raise Exception("registering module wile orchestrator is frozen")
-        self.modules.append(module)
+        self._modules.append(module)
 
     def realize(self) -> None:
-        self.frozen = True
+        self._frozen = True
-        for module in reversed(self.modules):
+        for module in reversed(self._modules):
+            print(f"[bold bright_magenta]\\[{escape(type(module).__name__)}]")
             module.realize()