Self-updates and program list from the repo

Catalog.py

@@ -0,0 +1,67 @@
+"""The program catalog: the Programs/ folder (manifests, templates, icons),
+fetched from the SaraSuite repo itself, so adding a program or fixing an
+install recipe only takes a push, not a new AppImage.
+
+The latest commit of the SaraSuite repo is checked the same way programs
+are (Sources.py). When it changed, its Programs/ folder is downloaded into
+~/.cache/SaraSuite/Catalog/. LoadPrograms() then reads that, falling back
+to the AppImage's bundled copy when there's no catalog yet, when it can't be
+loaded, or when running from source: there, the local Programs/ folder
+always wins, so unpushed manifest edits work while developing.
+"""
+
+import shutil
+from pathlib import Path
+from typing import Callable, Optional
+
+from Core import BundledManifestsDir, CacheHome, IsFrozen, LoadConfig
+from Sources import ClearDownloads, Download, LatestCommit, SourceError
+
+CatalogDir = CacheHome / "SaraSuite" / "Catalog"
+_CommitFile = CatalogDir / "Commit"
+_DownloadName = "SaraSuiteCatalog"
+
+
+def ManifestsDir() -> Path:
+    if IsFrozen and (CatalogDir / "Programs").is_dir():
+        return CatalogDir / "Programs"
+    return BundledManifestsDir
+
+
+def CatalogCommit() -> str:
+    return _CommitFile.read_text().strip() if _CommitFile.is_file() else ""
+
+
+def UpdateCatalog(Log: Optional[Callable[[str], None]] = None) -> bool:
+    """Fetch the SaraSuite repo's Programs/ if it has a new commit. Returns
+    True when the catalog changed (the program list should be reloaded).
+    Does nothing when running from source, and quietly keeps the current
+    catalog when the git host can't be reached."""
+    if not IsFrozen:
+        return False
+    Log = Log or (lambda Line: None)
+    Url = f"{LoadConfig().GitHost.rstrip('/')}/SaraSuite"
+    try:
+        Commit = LatestCommit(Url)
+    except SourceError:
+        return False
+    if Commit == CatalogCommit():
+        return False
+
+    try:
+        Source = Download(_DownloadName, Url, Commit, Log) / "Programs"
+        if not Source.is_dir():
+            return False
+        Staging = CatalogDir.with_name("Catalog.new")
+        shutil.rmtree(Staging, ignore_errors=True)
+        shutil.copytree(Source, Staging / "Programs", ignore=shutil.ignore_patterns("__pycache__"))
+        (Staging / "Commit").write_text(Commit)
+        shutil.rmtree(CatalogDir, ignore_errors=True)
+        Staging.rename(CatalogDir)
+    except (SourceError, OSError) as Error:
+        Log(f"Couldn't update the program list: {Error}")
+        return False
+    finally:
+        ClearDownloads(_DownloadName)
+    Log(f"Program list updated to SaraSuite commit {Commit[:7]}")
+    return True

Cli.py

@@ -5,12 +5,16 @@
     SaraSuite update <Name>
     SaraSuite options <Name> [--option Id=on|off ...]   (no --option: list them)
     SaraSuite remove <Name> [--configs] [--keep-runtime]
+    SaraSuite self-update                               (AppImage only)
 
 Install starts from your defaults (Settings, or the manifest's) unless set.
 """
 
 import argparse
 
+import SelfUpdate
+from Catalog import UpdateCatalog
+from Core import AppVersion
 from Installer import Apply, DefaultAnswers, DefaultOptions, FetchCommit, GetStatus, Remove
 from Manifests import LoadPrograms
 
@@ -45,8 +49,19 @@ def Run(Arguments: list[str]) -> int:
     RemoveCommand.add_argument("Name")
     RemoveCommand.add_argument("--configs", action="store_true")
     RemoveCommand.add_argument("--keep-runtime", action="store_true")
+    Commands.add_parser("self-update")
     Args = Parser.parse_args(Arguments)
 
+    if Args.Command == "self-update":
+        Latest = SelfUpdate.LatestRelease()
+        if Latest is None or not SelfUpdate.IsNewer(Latest.Version):
+            print(f"SaraSuite {AppVersion} is the latest.")
+            return 0
+        SelfUpdate.Install(Latest, print)
+        return 0
+
+    UpdateCatalog(print)  # the program list from the SaraSuite repo (AppImage only)
+
     Programs = {Program.Name.lower(): Program for Program in LoadPrograms()}
     if Args.Command == "list":
         for Program in Programs.values():

Core.py

@@ -14,6 +14,10 @@ import flet as ft
 import tomlkit
 
 AppName = "SaraSuite"
+# Compared with the latest Gitea release to offer self-updates (SelfUpdate.py).
+# Bump it, then run Packaging/Release.py, to publish a new SaraSuite.
+AppVersion = "1.1.0"
+IsFrozen = bool(getattr(sys, "frozen", False))  # running from the AppImage
 # Bundled in assets/fonts and always registered, so it works as FontFamily
 # without being installed. Any other FontFamily is looked up among the
 # system's installed fonts.
@@ -45,7 +49,7 @@ DownloadsDir = CacheHome / "SaraSuite" / "Downloads"  # extracted source archive
 # Bundled read-only files (program manifests, fonts). Inside a PyInstaller
 # build they're unpacked to sys._MEIPASS rather than next to the code.
 BundleDir = Path(getattr(sys, "_MEIPASS", Path(__file__).resolve().parent))
-ManifestsDir = BundleDir / "Programs"
+BundledManifestsDir = BundleDir / "Programs"  # the AppImage's own copy; see Catalog.py
 AssetsDir = BundleDir / "assets"
 
 

Main.py

@@ -10,9 +10,11 @@ from typing import Callable
 
 import flet as ft
 
+import SelfUpdate
+from Catalog import UpdateCatalog
 from Core import (
-    AppName, ApplyAppearance, AssetsDir, BuildTheme, BundledFontFamily, ChipButtonStyle, DataDir,
-    DataHome, EffectiveSettings, LoadConfig, ManifestsDir, Palette,
+    AppName, AppVersion, ApplyAppearance, AssetsDir, BuildTheme, BundledFontFamily, ChipButtonStyle, DataDir,
+    BundledManifestsDir, DataHome, EffectiveSettings, LoadConfig, Palette,
 )
 from Dialogs import ShowInstallDialog, ShowOptionsDialog, ShowRemoveDialog, ShowUpdateDialog
 from Installer import Apply, Fetch, FetchCommit, GetStatus, PlanConfigs, PlanRemoval, Remove, SourceVersion
@@ -31,7 +33,7 @@ _MenuIcon = DataDir / "SaraSuite.png"
 def _LoadFletIdentity():
     # Lives in Programs/ (bundled as data) because installed programs get a
     # copy of the same file next to them.
-    Spec = importlib.util.spec_from_file_location("FletIdentity", ManifestsDir / "FletIdentity.py")
+    Spec = importlib.util.spec_from_file_location("FletIdentity", BundledManifestsDir / "FletIdentity.py")
     Module = importlib.util.module_from_spec(Spec)
     Spec.loader.exec_module(Module)
     return Module
@@ -85,9 +87,12 @@ def Main(Page: ft.Page) -> None:
             del LogView.controls[: len(LogView.controls) - _MaxLogLines]
         LogView.update()
 
+    # Both lists are changed in place when the program list is updated from
+    # the SaraSuite repo (Catalog.py), so everything holding them stays valid.
     Programs = LoadPrograms()
     Cards: list[ProgramCard] = []
-    State = {"Busy": False}
+    CardList = ft.ListView(Cards, expand=True, spacing=12, padding=16)
+    State = {"Busy": False, "Release": None}
 
     def RefreshCard(Card: ProgramCard) -> None:
         try:
@@ -99,17 +104,70 @@ def Main(Page: ft.Page) -> None:
         Card.ShowStatus(Current, Leftovers, State["Busy"])
         Card.update()
 
+    def BuildCards() -> None:
+        Cards[:] = [ProgramCard(Program, OnInstall, OnUpdate, OnRemove, OnOptions) for Program in Programs]
+        CardList.controls = Cards
+
     def RefreshAll() -> None:
+        # A new program list from the SaraSuite repo first, then every
+        # program's status, then whether there's a newer SaraSuite.
+        if UpdateCatalog(Log):
+            Programs[:] = LoadPrograms()
+            BuildCards()
+            CardList.update()
         for Card in Cards:
             RefreshCard(Card)
+        CheckSelfUpdate()
+
+    def CanSelfUpdate() -> bool:
+        Latest = State["Release"]
+        return Latest is not None and bool(Latest.AssetUrl) and SelfUpdate.RunningAppImage() is not None
+
+    def CheckSelfUpdate() -> None:
+        Latest = SelfUpdate.LatestRelease()
+        State["Release"] = Latest if Latest is not None and SelfUpdate.IsNewer(Latest.Version) else None
+        if State["Release"] is None:
+            SelfUpdateButton.visible = False
+        else:
+            Version = State["Release"].Version.lstrip("v")
+            # Only an AppImage can replace itself; from source, just say so.
+            SelfUpdateButton.visible = True
+            SelfUpdateButton.disabled = not CanSelfUpdate()
+            SelfUpdateButton.content = f"Update SaraSuite to {Version}"
+            SelfUpdateButton.tooltip = None if not SelfUpdateButton.disabled else "Running from source: pull and rebuild instead"
+        SelfUpdateButton.update()
+
+    def OnSelfUpdate(e) -> None:
+        Latest = State["Release"]
+        if Latest is None:
+            return
+
+        def Work() -> None:
+            SelfUpdate.Install(Latest, Log)
+            Page.show_dialog(ft.AlertDialog(
+                title="SaraSuite updated",
+                content=ft.Text(f"SaraSuite {Latest.Version.lstrip('v')} is installed. Restart now to use it?"),
+                actions=[
+                    ft.OutlinedButton(content="Later", style=ChipButtonStyle(), on_click=lambda e: Page.pop_dialog()),
+                    ft.OutlinedButton(content="Restart", style=ChipButtonStyle(), on_click=lambda e: Restart()),
+                ],
+            ))
+
+        def Restart() -> None:
+            SelfUpdate.Restart()
+            Page.run_task(Page.window.destroy)
+
+        RunOperation(None, Work)
 
     def SetBusy(Busy: bool, Working: ProgramCard | None = None) -> None:
         State["Busy"] = Busy
         RefreshButton.disabled = Busy
+        SelfUpdateButton.disabled = Busy or not CanSelfUpdate()
         for Card in Cards:
             Card.SetBusy(Busy, Card is Working)
             Card.update()
         RefreshButton.update()
+        SelfUpdateButton.update()
 
     def RunOperation(Card: ProgramCard | None, Work: Callable[[], None]) -> None:
         """Run Work in a background thread with every card locked, then
@@ -180,8 +238,7 @@ def Main(Page: ft.Page) -> None:
             ),
         )
 
-    for Program in Programs:
-        Cards.append(ProgramCard(Program, OnInstall, OnUpdate, OnRemove, OnOptions))
+    BuildCards()
 
     def ToggleMenuEntry(e) -> None:
         _SetMenuEntry(not _MenuEntry.exists())
@@ -195,6 +252,10 @@ def Main(Page: ft.Page) -> None:
         on_click=ToggleMenuEntry,
     )
 
+    SelfUpdateButton = ft.OutlinedButton(
+        content="Update SaraSuite", style=ChipButtonStyle(), visible=False, on_click=OnSelfUpdate,
+    )
+
     RefreshButton = ft.IconButton(
         icon=ft.Icons.REFRESH,
         icon_color=Palette.Mauve,
@@ -217,7 +278,9 @@ def Main(Page: ft.Page) -> None:
                 ft.Container(
                     content=ft.Row([
                         ft.Text(AppName, size=24, color=Palette.Mauve),
+                        ft.Text(AppVersion, size=12, color=Palette.Overlay0),
                         ft.Container(expand=True),
+                        SelfUpdateButton,
                         MenuButton,
                         RefreshButton,
                         SettingsButton,
@@ -226,7 +289,7 @@ def Main(Page: ft.Page) -> None:
                     bgcolor=Palette.Mantle,
                     border=ft.Border.only(bottom=ft.BorderSide(1, Palette.Surface1)),
                 ),
-                ft.ListView(Cards, expand=True, spacing=12, padding=16),
+                CardList,
                 ft.Container(
                     content=LogView,
                     height=200,

Manifests.py

@@ -11,7 +11,7 @@ from typing import Optional
 import tomlkit
 
 from Core import (
-    CacheHome, ConfigHome, CurrentDesktop, DataHome, Home, LoadConfig, ManifestsDir, ProgramsDir,
+    CacheHome, ConfigHome, CurrentDesktop, DataHome, Home, LoadConfig, ProgramsDir,
     SharedConfigDir,
 )
 
@@ -230,14 +230,22 @@ def LoadProgram(Folder: Path) -> Program:
     )
 
 
+def _LoadFrom(Folder: Path) -> list[Program]:
+    return [LoadProgram(Child) for Child in sorted(Folder.iterdir()) if (Child / "Manifest.toml").exists()]
+
+
 def LoadPrograms() -> list[Program]:
     """Alphabetical, with each program's children (Parent = its Name) right
-    after it. A child whose parent isn't there keeps its own place."""
-    Loaded = [
-        LoadProgram(Folder)
-        for Folder in sorted(ManifestsDir.iterdir())
-        if (Folder / "Manifest.toml").exists()
-    ]
+    after it. A child whose parent isn't there keeps its own place.
+    Read from the catalog fetched from the SaraSuite repo (Catalog.py) when
+    there is one, falling back to the bundled copy if that can't be loaded
+    (e.g. it uses a manifest feature this SaraSuite doesn't know yet)."""
+    from Catalog import BundledManifestsDir, ManifestsDir
+
+    try:
+        Loaded = _LoadFrom(ManifestsDir())
+    except Exception:
+        Loaded = _LoadFrom(BundledManifestsDir)
     Names = {Current.Name for Current in Loaded}
     Ordered = []
     for Current in Loaded:

Packaging/Release.py

@@ -0,0 +1,120 @@
+#!/usr/bin/env python3
+"""Publish a SaraSuite release: build the AppImage, create the Gitea release
+v<AppVersion> (from Core.py) with it attached, and copy it to the Shared
+folder. Running SaraSuites then offer to update themselves (SelfUpdate.py).
+
+    Packaging/Release.py            # after bumping AppVersion in Core.py
+    Packaging/Release.py --notes "What changed"
+
+Everything must be committed and pushed first, so the release's tag points
+at code that's actually on Gitea. The Gitea token comes from git's own
+credential store (the same one `git push` uses), so there's nothing to set up.
+"""
+
+import argparse
+import json
+import os
+import re
+import shutil
+import subprocess
+import sys
+import urllib.error
+import urllib.request
+import uuid
+from pathlib import Path
+from urllib.parse import urlsplit
+
+RepoDir = Path(__file__).resolve().parent.parent
+AppImage = RepoDir / "dist" / "SaraSuite-x86_64.AppImage"
+SharedDir = Path("/mnt/files/Shared/SaraSuite")
+
+
+def Git(*Args: str) -> str:
+    return subprocess.run(["git", *Args], cwd=RepoDir, capture_output=True, text=True, check=True).stdout.strip()
+
+
+def Fail(Message: str) -> None:
+    sys.exit(f"Release.py: {Message}")
+
+
+def Token(Host: str) -> str:
+    Result = subprocess.run(
+        ["git", "credential", "fill"], input=f"protocol=https\nhost={Host}\n\n",
+        capture_output=True, text=True, env={**os.environ, "GIT_TERMINAL_PROMPT": "0"},
+    )
+    Found = re.search(r"^password=(.+)$", Result.stdout, re.MULTILINE)
+    if not Found:
+        Fail(f"no Gitea token for {Host} in git's credential store; push once so git saves it")
+    return Found[1]
+
+
+def Api(Method: str, Url: str, TokenValue: str, Body: bytes | None = None, ContentType: str = "application/json"):
+    Request = urllib.request.Request(Url, data=Body, method=Method, headers={
+        "Authorization": f"token {TokenValue}", "Content-Type": ContentType, "Accept": "application/json",
+    })
+    try:
+        with urllib.request.urlopen(Request, timeout=300) as Response:
+            return json.loads(Response.read() or b"null")
+    except urllib.error.HTTPError as Error:
+        if Error.code == 404:
+            return None
+        Fail(f"{Method} {Url} failed: {Error.code} {Error.read().decode(errors='replace')[:300]}")
+
+
+def Main() -> None:
+    Parser = argparse.ArgumentParser(description="Publish a SaraSuite release on Gitea.")
+    Parser.add_argument("--notes", default="", help="release notes (default: the commits since the last release)")
+    Args = Parser.parse_args()
+
+    Version = re.search(r'^AppVersion = "([^"]+)"', (RepoDir / "Core.py").read_text(), re.MULTILINE)[1]
+    Tag = f"v{Version}"
+
+    # origin is e.g. https://git.srhtnin.garden/sarah/SaraSuite.git
+    Origin = urlsplit(Git("remote", "get-url", "origin"))
+    Owner, Repo = Origin.path.strip("/").removesuffix(".git").split("/")[-2:]
+    ApiBase = f"{Origin.scheme}://{Origin.netloc}/api/v1/repos/{Owner}/{Repo}"
+
+    if Git("status", "--porcelain"):
+        Fail("there are uncommitted changes; commit (and push) first")
+    Branch = Git("rev-parse", "--abbrev-ref", "HEAD")
+    Git("fetch", "--quiet", "--tags", "origin")
+    Head = Git("rev-parse", "HEAD")
+    if Head != Git("rev-parse", f"origin/{Branch}"):
+        Fail(f"{Branch} isn't pushed (or is behind origin); push first")
+    TokenValue = Token(Origin.netloc)
+    if Api("GET", f"{ApiBase}/releases/tags/{Tag}", TokenValue) is not None:
+        Fail(f"{Tag} is already released; bump AppVersion in Core.py first")
+
+    Notes = Args.notes
+    if not Notes:
+        Previous = Git("tag", "--list", "v*", "--sort=-v:refname").splitlines()
+        Range = f"{Previous[0]}..HEAD" if Previous else "HEAD"
+        Notes = Git("log", "--format=- %s", Range) or "- First release with self-updates."
+
+    print(f"== Building SaraSuite {Version}")
+    subprocess.run(["Packaging/BuildAppImage.sh"], cwd=RepoDir, check=True,
+                   env={**os.environ, "PATH": f"{Path.home()}/.local/bin:{os.environ['PATH']}"})
+
+    print(f"== Creating release {Tag}")
+    Created = Api("POST", f"{ApiBase}/releases", TokenValue, json.dumps({
+        "tag_name": Tag, "target_commitish": Head, "name": f"SaraSuite {Version}", "body": Notes,
+    }).encode())
+
+    print(f"== Uploading {AppImage.name} ({AppImage.stat().st_size // 1_000_000} MB)")
+    Boundary = uuid.uuid4().hex
+    Body = (
+        f"--{Boundary}\r\nContent-Disposition: form-data; name=\"attachment\"; filename=\"{AppImage.name}\"\r\n"
+        f"Content-Type: application/octet-stream\r\n\r\n"
+    ).encode() + AppImage.read_bytes() + f"\r\n--{Boundary}--\r\n".encode()
+    Api("POST", f"{ApiBase}/releases/{Created['id']}/assets?name={AppImage.name}", TokenValue, Body,
+        f"multipart/form-data; boundary={Boundary}")
+
+    if SharedDir.is_dir():
+        shutil.copy2(AppImage, SharedDir / AppImage.name)
+        print(f"== Copied to {SharedDir}")
+    Git("fetch", "--quiet", "--tags", "origin")  # the new tag, for the next release's notes
+    print(f"== Released {Tag}: {Origin.scheme}://{Origin.netloc}/{Owner}/{Repo}/releases/tag/{Tag}")
+
+
+if __name__ == "__main__":
+    Main()

README.md

@@ -30,6 +30,23 @@ GitHost = "https://git.srhtnin.garden/sarah"
 
 The only thing a program needs from the system is `python3` (for its venv).
 
+## Updates
+
+- **Programs** update from their own repos (see Sources above).
+- **The program list** (`Programs/`: manifests, templates, icons) is fetched from this repo
+  whenever it has a new commit, so adding a program or fixing a recipe only takes a push. It's
+  cached in `~/.cache/SaraSuite/Catalog/`; the AppImage's bundled copy is the fallback. Running
+  from source always uses the local `Programs/`.
+- **SaraSuite itself** checks this repo's latest Gitea release. When it's newer than its own
+  `AppVersion`, an "Update SaraSuite" button downloads the new AppImage, swaps it in place (same
+  path, so the app menu entry keeps working) and restarts. From a terminal:
+  `SaraSuite-x86_64.AppImage self-update`.
+
+To publish a new SaraSuite: bump `AppVersion` in `Core.py`, commit and push, then run
+`Packaging/Release.py` (optionally `--notes "..."`). It builds the AppImage, creates the release
+`v<AppVersion>` with the AppImage attached, and copies it to the Shared folder. The Gitea token
+comes from git's credential store, the same one `git push` uses.
+
 ## Shared settings
 
 Settings every SaraSuite program shares live in `~/.config/SaraSuite/Config.toml`:

SelfUpdate.py

@@ -0,0 +1,93 @@
+"""SaraSuite updating itself from its Gitea releases.
+
+Packaging/Release.py publishes a release (tag v<AppVersion>) with the
+AppImage attached. Here SaraSuite asks Gitea for the latest release, and if
+it's newer than AppVersion and SaraSuite runs as an AppImage, downloads it
+next to the running one and renames it into place (allowed while it's
+running), then restarts into it. The AppImage keeps its path, so its app
+menu entry keeps working.
+"""
+
+import os
+import subprocess
+from dataclasses import dataclass
+from pathlib import Path
+from typing import Callable, Optional
+from urllib.parse import urlsplit
+
+from Core import AppName, AppVersion, ChildEnvironment, LoadConfig
+from Sources import GetBytes, GetJson, SourceError
+
+AssetName = f"{AppName}-x86_64.AppImage"
+
+
+@dataclass
+class Release:
+    Version: str
+    AssetUrl: str  # empty if the release has no AppImage attached
+
+
+def RunningAppImage() -> Optional[Path]:
+    Value = os.environ.get("APPIMAGE", "")
+    return Path(Value) if Value else None
+
+
+def _VersionTuple(Version: str) -> tuple[int, ...]:
+    Parts = []
+    for Part in Version.strip().lstrip("vV").split("."):
+        Digits = "".join(Char for Char in Part if Char.isdigit())
+        Parts.append(int(Digits) if Digits else 0)
+    return tuple(Parts)
+
+
+def IsNewer(Version: str) -> bool:
+    return _VersionTuple(Version) > _VersionTuple(AppVersion)
+
+
+def LatestRelease() -> Optional[Release]:
+    """The latest published release, or None if there's none or the git host
+    can't be reached. GitHost looks like https://host/owner; the API lives at
+    https://host/api/v1."""
+    Parts = urlsplit(LoadConfig().GitHost.rstrip("/"))
+    Owner = Parts.path.strip("/").split("/")[-1]
+    Url = f"{Parts.scheme}://{Parts.netloc}/api/v1/repos/{Owner}/{AppName}/releases/latest"
+    try:
+        Data = GetJson(Url)
+    except SourceError:
+        return None
+    Asset = next((Item for Item in Data.get("assets", []) if Item.get("name") == AssetName), None)
+    return Release(Data.get("tag_name", ""), Asset.get("browser_download_url", "") if Asset else "")
+
+
+def Install(Latest: Release, Log: Callable[[str], None]) -> Path:
+    """Replace the running AppImage with Latest's. Raises OSError/SourceError."""
+    Target = RunningAppImage()
+    if Target is None:
+        raise OSError("SaraSuite isn't running as an AppImage, so it can't replace itself.")
+    if not Latest.AssetUrl:
+        raise OSError(f"Release {Latest.Version} has no {AssetName} attached.")
+    Log(f"== Updating {AppName} {AppVersion} -> {Latest.Version.lstrip('v')}")
+    Log(f"Downloading {Latest.AssetUrl}")
+    Data = GetBytes(Latest.AssetUrl)
+    if not Data.startswith(b"\x7fELF"):
+        raise OSError("The download isn't an AppImage; leaving the current one alone.")
+    # Same folder, so the rename is atomic; renaming over a running AppImage
+    # is fine (overwriting it in place isn't: "Text file busy").
+    Temporary = Target.with_name(Target.name + ".new")
+    Temporary.write_bytes(Data)
+    Temporary.chmod(0o755)
+    Temporary.replace(Target)
+    Log(f"== {AppName} updated; it's the new version from the next start")
+    return Target
+
+
+def Restart() -> None:
+    """Start the (new) AppImage; the caller then closes this one."""
+    Target = RunningAppImage()
+    if Target is None:
+        return
+    Environment = ChildEnvironment()
+    for Key in ("APPIMAGE", "APPDIR", "ARGV0", "OWD"):  # the new AppImage sets its own
+        Environment.pop(Key, None)
+    subprocess.Popen([str(Target)], env=Environment, start_new_session=True,
+                     stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)

Sources.py

@@ -40,6 +40,20 @@ def _Get(Url: str) -> bytes:
         raise SourceError(f"Couldn't reach {Url}: {Error}") from Error
 
 
+def GetBytes(Url: str) -> bytes:
+    return _Get(Url)
+
+
+def GetJson(Url: str):
+    """A JSON API response (e.g. Gitea's latest release), or SourceError."""
+    import json
+
+    try:
+        return json.loads(_Get(Url))
+    except ValueError as Error:
+        raise SourceError(f"{Url} didn't return JSON: {Error}") from Error
+
+
 def _RepoUrl(GitUrl: str) -> str:
     return GitUrl.rstrip("/").removesuffix(".git")