Allow specifying rules to perform arbitrary actions in kitty when opening URLs

kitty/boss.py

@@ -1016,9 +1016,17 @@ class Boss:
             tab.set_active_window(window_id)
 
     def open_url(self, url: str, program: Optional[Union[str, List[str]]] = None, cwd: Optional[str] = None) -> None:
-        if url:
-            if isinstance(program, str):
-                program = to_cmdline(program)
+        if not url:
+            return
+        if isinstance(program, str):
+            program = to_cmdline(program)
+        found_action = False
+        if program is None:
+            from .open_actions import actions_for_url
+            for action in actions_for_url(url):
+                found_action = True
+                self.dispatch_action(action)
+        if not found_action:
             open_url(url, program or self.opts.open_url_with, cwd=cwd)
 
     def destroy(self) -> None:

kitty/open_actions.py

@@ -0,0 +1,180 @@
+#!/usr/bin/env python
+# vim:fileencoding=utf-8
+# License: GPLv3 Copyright: 2020, Kovid Goyal <kovid at kovidgoyal.net>
+
+
+import os
+import posixpath
+from contextlib import suppress
+from functools import lru_cache
+from typing import Generator, Iterable, List, NamedTuple, Optional, Tuple, cast
+from urllib.parse import ParseResult, unquote, urlparse
+
+from .conf.utils import to_bool, to_cmdline
+from .config import KeyAction, parse_key_action
+from .constants import config_dir
+from .typing import MatchType
+from .utils import expandvars, log_error
+
+
+class MatchCriteria(NamedTuple):
+    type: MatchType
+    value: str
+
+
+class OpenAction(NamedTuple):
+    match_criteria: Tuple[MatchCriteria, ...]
+    actions: Tuple[KeyAction, ...]
+
+
+def parse(lines: Iterable[str]) -> Generator[OpenAction, None, None]:
+    match_criteria: List[MatchCriteria] = []
+    actions: List[KeyAction] = []
+
+    for line in lines:
+        line = line.strip()
+        if line.startswith('#'):
+            continue
+        if not line:
+            if match_criteria and actions:
+                yield OpenAction(tuple(match_criteria), tuple(actions))
+            match_criteria = []
+            actions = []
+            continue
+        parts = line.split(maxsplit=1)
+        if len(parts) != 2:
+            continue
+        key, rest = parts
+        key = key.lower()
+        if key == 'action':
+            with to_cmdline.filter_env_vars('URL', 'FILE_PATH', 'FILE', 'FRAGMENT'):
+                x = parse_key_action(rest)
+            if x is not None:
+                actions.append(x)
+        elif key in ('mime', 'ext', 'protocol', 'file', 'path', 'url', 'has_fragment'):
+            if key != 'url':
+                rest = rest.lower()
+            match_criteria.append(MatchCriteria(cast(MatchType, key), rest))
+        else:
+            log_error(f'Ignoring malformed open actions line: {line}')
+
+    if match_criteria and actions:
+        yield OpenAction(tuple(match_criteria), tuple(actions))
+
+
+def url_matches_criterion(purl: 'ParseResult', url: str, mc: MatchCriteria) -> bool:
+    if mc.type == 'url':
+        import re
+        try:
+            pat = re.compile(mc.value)
+        except re.error:
+            return False
+        return pat.search(url) is not None
+
+    if mc.type == 'mime':
+        import fnmatch
+        from mimetypes import guess_type
+        try:
+            mt = guess_type(purl.path)[0]
+        except Exception:
+            return False
+        if mt is None:
+            return False
+        mt = mt.lower()
+        for mpat in mc.value.split(','):
+            mpat = mpat.strip()
+            with suppress(Exception):
+                if fnmatch.fnmatchcase(mt, mpat):
+                    return True
+        return False
+
+    if mc.type == 'ext':
+        if not purl.path:
+            return False
+        path = purl.path.lower()
+        for ext in mc.value.split(','):
+            ext = ext.strip()
+            if path.endswith('.' + ext):
+                return True
+        return False
+
+    if mc.type == 'protocol':
+        protocol = (purl.scheme or 'file').lower()
+        for key in mc.value.split(','):
+            if key.strip() == protocol:
+                return True
+        return False
+
+    if mc.type == 'has_fragment':
+        return to_bool(mc.value) == bool(purl.fragment)
+
+    if mc.type == 'path':
+        import fnmatch
+        try:
+            return fnmatch.fnmatchcase(purl.path.lower(), mc.value)
+        except Exception:
+            return False
+
+    if mc.type == 'file':
+        import fnmatch
+        import posixpath
+        try:
+            fname = posixpath.basename(purl.path)
+        except Exception:
+            return False
+        try:
+            return fnmatch.fnmatchcase(fname.lower(), mc.value)
+        except Exception:
+            return False
+
+
+def url_matches_criteria(purl: 'ParseResult', url: str, criteria: Iterable[MatchCriteria]) -> bool:
+    for x in criteria:
+        try:
+            if not url_matches_criterion(purl, url, x):
+                return False
+        except Exception:
+            return False
+    return True
+
+
+def actions_for_url_from_list(url: str, actions: Iterable[OpenAction]) -> Generator[KeyAction, None, None]:
+    try:
+        purl = urlparse(url)
+    except Exception:
+        return
+    path = unquote(purl.path)
+
+    env = {
+        'URL': url,
+        'FILE_PATH': path,
+        'FILE': posixpath.basename(path),
+        'FRAGMENT': purl.fragment
+    }
+
+    def expand(x: str) -> str:
+        return expandvars(x, env, fallback_to_os_env=False)
+
+    for action in actions:
+        if url_matches_criteria(purl, url, action.match_criteria):
+            for ac in action.actions:
+                yield ac._replace(args=tuple(map(expand, ac.args)))
+            return
+
+
+@lru_cache(maxsize=2)
+def load_open_actions() -> Tuple[OpenAction, ...]:
+    try:
+        f = open(os.path.join(config_dir, 'open-actions.conf'))
+    except FileNotFoundError:
+        return ()
+    with f:
+        return tuple(parse(f))
+
+
+def actions_for_url(url: str, actions_spec: Optional[str] = None) -> Generator[KeyAction, None, None]:
+    if actions_spec is None:
+        actions = load_open_actions()
+    else:
+        actions = tuple(parse(actions_spec.splitlines()))
+    yield from actions_for_url_from_list(url, actions)

kitty/typing.py

@@ -18,4 +18,5 @@ TermManagerType = LoopType = Debug = GraphicsCommandType = None
 CompletedProcess = Tuple
 TypedDict = dict
 EdgeLiteral = str
+MatchType = str
 Protocol = object

kitty/typing.pyi

@@ -43,6 +43,7 @@ from .config import (  # noqa; noqa
 )
 
 EdgeLiteral = Literal['left', 'top', 'right', 'bottom']
+MatchType = Literal['mime', 'ext', 'protocol', 'file', 'path', 'url', 'has_fragment']
 GRT_a = Literal['t', 'T', 'q', 'p', 'd']
 GRT_f = Literal[24, 32, 100]
 GRT_t = Literal['d', 'f', 't', 's']

kitty_tests/open_actions.py

@@ -0,0 +1,57 @@
+#!/usr/bin/env python3
+# vim:fileencoding=utf-8
+# License: GPL v3 Copyright: 2018, Kovid Goyal <kovid at kovidgoyal.net>
+
+
+import os
+from contextlib import contextmanager
+
+from . import BaseTest
+
+
+@contextmanager
+def patch_env(**kw):
+    orig = os.environ.copy()
+    for k, v in kw.items():
+        if v is None:
+            os.environ.pop(k, None)
+        else:
+            os.environ[k] = v
+    yield
+    os.environ.clear()
+    os.environ.update(orig)
+
+
+class TestOpenActions(BaseTest):
+
+    def test_parsing_of_open_actions(self):
+        from kitty.open_actions import actions_for_url, KeyAction
+        spec = '''
+protocol file
+mime text/*
+has_fragment yes
+AcTion launch $EDITOR $FILE_PATH $FRAGMENT
+action
+
+protocol file
+mime text/*
+action ignored
+
+ext py,txt
+action one
+action two
+'''
+
+        def actions(url):
+            with patch_env(EDITOR='editor', FILE_PATH='notgood'):
+                return tuple(actions_for_url(url, spec))
+
+        def single(url, func, *args):
+            acts = actions(url)
+            self.ae(len(acts), 1)
+            self.ae(acts[0].func, func)
+            self.ae(acts[0].args, args)
+
+        single('file://hostname/tmp/moo.txt#23', 'launch', 'editor', '/tmp/moo.txt', '23')
+        single('some thing.txt', 'ignored')
+        self.ae(actions('x:///a.txt'), (KeyAction('one', ()), KeyAction('two', ())))