calcurse: one-click Google login renewal

On expiry calcurse-sync starts calcurse-relogin, a notification that opens the consent page when clicked and catches the OAuth code on 127.0.0.1:8749. dunst's left-click now runs a notification's action before closing it.

.local/bin/calcurse-relogin

@@ -0,0 +1,101 @@
+#!/usr/bin/env python3
+"""Renew calcurse-caldav's Google login: catch the OAuth redirect on 127.0.0.1 and hand the code to calcurse-sync.
+
+--prompt shows a notification first and logs in when it is clicked.
+"""
+
+import argparse
+import configparser
+import os
+import subprocess
+import sys
+import time
+import urllib.parse
+from http.server import BaseHTTPRequestHandler, HTTPServer
+from pathlib import Path
+
+CONFIG = Path(os.environ.get("XDG_CONFIG_HOME", Path.home() / ".config")) / "calcurse" / "caldav" / "config"
+WAIT_SECONDS = 300
+
+
+def notify(summary: str, body: str = "", *extra: str) -> str:
+    """Send a calcurse notification; with actions in extra, wait and return the chosen action's name."""
+    cmd = ["notify-send", "-a", "calcurse", "-i", "x-office-calendar", *extra, summary, body]
+    return subprocess.run(cmd, capture_output=True, text=True).stdout.strip()
+
+
+def redirect_port() -> int:
+    parser = configparser.RawConfigParser()
+    parser.read(CONFIG)
+    uri = urllib.parse.urlparse(parser.get("OAuth2", "RedirectURI", fallback=""))
+    if uri.hostname != "127.0.0.1" or uri.port is None:
+        sys.exit(f"RedirectURI in {CONFIG} must be http://127.0.0.1:<port>")
+    return uri.port
+
+
+def ui_running() -> bool:
+    ttys = subprocess.run(["ps", "-C", "calcurse", "-o", "tty="], capture_output=True, text=True).stdout.split()
+    return any(tty != "?" for tty in ttys)
+
+
+class RedirectHandler(BaseHTTPRequestHandler):
+    result: dict[str, str] = {}
+
+    def do_GET(self) -> None:
+        query = urllib.parse.parse_qs(urllib.parse.urlparse(self.path).query)
+        for key in ("code", "error"):
+            if key in query:
+                RedirectHandler.result[key] = query[key][0]
+        done = bool(RedirectHandler.result)
+        self.send_response(200 if done else 404)
+        self.send_header("Content-Type", "text/plain; charset=utf-8")
+        self.end_headers()
+        if done:
+            self.wfile.write(b"calcurse: login received, you can close this tab.\n")
+
+    def log_message(self, format: str, *args: object) -> None:
+        pass
+
+
+def login() -> int:
+    if ui_running():
+        notify("Google Calendar login", "Close calcurse first, then log in again.", "-u", "critical")
+        return 1
+    server = HTTPServer(("127.0.0.1", redirect_port()), RedirectHandler)
+    # With an expired login calcurse-caldav opens the consent page and exits; with a valid one it just syncs.
+    if subprocess.run(["calcurse-caldav"], capture_output=True).returncode == 0:
+        notify("Google Calendar login", "Already logged in.")
+        return 0
+    deadline = time.monotonic() + WAIT_SECONDS
+    while not RedirectHandler.result and (left := deadline - time.monotonic()) > 0:
+        server.timeout = left
+        server.handle_request()
+    server.server_close()
+    code = RedirectHandler.result.get("code")
+    if not code:
+        reason = RedirectHandler.result.get("error", "no answer from the browser")
+        notify("Google Calendar login failed", reason, "-u", "critical")
+        return 1
+    # The user manager's PATH lacks ~/.local/bin: call calcurse-sync from this script's folder.
+    calcurse_sync = Path(__file__).resolve().with_name("calcurse-sync")
+    sync = subprocess.run([calcurse_sync, "--authcode", code], capture_output=True, text=True)
+    if sync.returncode != 0:
+        last_line = (sync.stdout.strip().splitlines() or [""])[-1]
+        notify("Google Calendar login failed", last_line, "-u", "critical")
+        return 1
+    notify("Google Calendar login renewed", "Synced again.")
+    return 0
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description=__doc__.splitlines()[0])
+    parser.add_argument("--prompt", action="store_true", help="ask with a notification before logging in")
+    if parser.parse_args().prompt:
+        body = "Click to log in again, then click Allow in the browser."
+        if notify("Google Calendar login expired", body, "-u", "critical", "-A", "default=Log in") != "default":
+            return 0
+    return login()
+
+
+if __name__ == "__main__":
+    sys.exit(main())

.local/bin/calcurse-sync

@@ -1,13 +1,18 @@
 #!/bin/bash
-# Sync calcurse with Google Calendar via calcurse-caldav; notify once when the weekly OAuth login expires.
+# Sync calcurse with Google Calendar via calcurse-caldav; start the login prompt when the weekly OAuth login expires.
 # --now: called from the UI's pre-load hook (skip the UI check, shorter timeout, no daemon restart).
+# --authcode CODE: finish a login (from calcurse-relogin, which checks for the UI itself).
 set -uo pipefail
 
 data=${XDG_DATA_HOME:-$HOME/.local/share}/calcurse
 state=${XDG_STATE_HOME:-$HOME/.local/state}/calcurse-sync
 expired_flag=$state/login-expired
 now=false
-[[ ${1:-} == --now ]] && now=true
+authcode=()
+case ${1:-} in
+--now) now=true ;;
+--authcode) authcode=(--authcode "$2") ;;
+esac
 
 # The UI keeps the data in memory, so syncing under it would lose changes; its post-save hook syncs after it exits.
 ui_running() {
@@ -15,22 +20,22 @@ ui_running() {
     ps -C calcurse -o tty= | grep -qv '?'
 }
 
-if ! $now && ui_running; then
+if ! $now && ((${#authcode[@]} == 0)) && ui_running; then
     echo "calcurse UI is running, skipping"
     exit 0
 fi
 
 mkdir -p "$state"
 # BROWSER=true: an expired login must not open browser tabs on its own.
-out=$(BROWSER=true timeout "$($now && echo 15 || echo 60)" calcurse-caldav 2>&1)
+out=$(BROWSER=true timeout "$($now && echo 15 || echo 60)" calcurse-caldav "${authcode[@]}" 2>&1)
 rc=$?
 printf '%s\n' "$out"
 
 if ((rc != 0)); then
     if grep -q 'Access token is missing or refresh token is expired' <<<"$out"; then
-        if [[ ! -e $expired_flag ]]; then
-            notify-send -a calcurse -u critical -i x-office-calendar "Google Calendar login expired" \
-                "Run calcurse-caldav in a terminal, allow access in the browser, then calcurse-caldav --authcode '<code>'."
+        # Prompt via calcurse-relogin, again daily if the prompt was dismissed.
+        if [[ ! -e $expired_flag || -n $(find "$expired_flag" -mmin +1440) ]]; then
+            systemctl --user start --no-block calcurse-relogin.service
             touch "$expired_flag"
         fi
     elif grep -q 'Another synchronization instance' <<<"$out"; then