add modifiable config options

Author: rmorshea

.pre-commit-config.yaml

@@ -7,11 +7,6 @@ repos:
     rev: 3.7.9
     hooks:
       - id: flake8
-  - repo: https://github.com/kynan/nbstripout
-    rev: 0.3.9
-    hooks:
-      - id: nbstripout
-        files: ".ipynb"
   - repo: https://github.com/pycqa/isort
     rev: 5.6.3
     hooks:

docs/source/package-api.rst

@@ -100,3 +100,10 @@ Useful Tools
 
 .. automodule:: idom.utils
     :members:
+
+
+Configuration Options
+---------------------
+
+.. automodule:: idom.config
+    :members:

src/idom/__init__.py

@@ -7,7 +7,7 @@
     # package is not installed
     __version__ = "0.0.0"
 
-from . import log
+from . import config, log
 from .client.module import Import, Module, install
 from .core import hooks
 from .core.component import Component, component
@@ -58,4 +58,5 @@
     "client",
     "install",
     "log",
+    "config",
 ]

src/idom/_option.py

@@ -0,0 +1,37 @@
+import os
+from typing import Callable, Generic, TypeVar
+
+_O = TypeVar("_O")
+
+
+class Option(Generic[_O]):
+    """An option that can be set using an environment variable of the same name"""
+
+    def __init__(
+        self,
+        name: str,
+        default: _O,
+        allow_changes: bool = True,
+        from_string: Callable[[str], _O] = lambda x: x,
+    ) -> None:
+        self.name = name
+        self._default = default
+        self._allow_changes = allow_changes
+        assert name == name.upper()
+        if name not in os.environ:
+            self._value = default
+        else:
+            self._value = from_string(os.environ[name])
+
+    def get(self) -> _O:
+        return self._value
+
+    def set(self, new: _O) -> _O:
+        if not self._allow_changes:
+            raise ValueError(f"{self.name} cannot be modified.")
+        old = self._value
+        self._value = new
+        return old
+
+    def reset(self) -> _O:
+        return self.set(self._default)

src/idom/_options.py

@@ -1,4 +1,3 @@
 node_modules
 web_modules
 build
-src/user-packages.js

src/idom/client/app/.gitignore

@@ -6,28 +6,36 @@
 from tempfile import TemporaryDirectory
 from typing import List, Sequence, Set, Union
 
+from idom.config import IDOM_CLIENT_BUILD_DIR
+
 from .utils import find_js_module_exports_in_source, get_package_name
 
 logger = getLogger(__name__)
 
 
-THIS_DIR = Path(__file__).parent
-# these directories are never modified
-APP_DIR = THIS_DIR / "app"
-BACKUP_BUILD_DIR = APP_DIR / "build"
+_THIS_DIR = Path(__file__).parent
+_APP_DIR = _THIS_DIR / "app"
+_BACKUP_BUILD_DIR = _APP_DIR / "build"
 # these directory are modified when users install packages
-BUILD_DIR = THIS_DIR / "build"
-WEB_MODULES_DIR = BUILD_DIR / "_snowpack" / "pkg"
+
+
+def _build_dir() -> Path:
+    return IDOM_CLIENT_BUILD_DIR.get()
+
+
+def _web_modules_dir() -> Path:
+    return _build_dir() / "_snowpack" / "pkg"
 
 
 def _copy_to_build_dir(source: Path) -> None:
-    if BUILD_DIR.exists():
-        shutil.rmtree(BUILD_DIR)
-    shutil.copytree(source, BUILD_DIR, symlinks=True)
+    target = _build_dir()
+    if target.exists():
+        shutil.rmtree(target)
+    shutil.copytree(source, target, symlinks=True)
 
 
-if not BUILD_DIR.exists():  # coverage: skip
-    _copy_to_build_dir(BACKUP_BUILD_DIR)
+if not _build_dir().exists():  # coverage: skip
+    _copy_to_build_dir(_BACKUP_BUILD_DIR)
 
 
 def web_module_exports(package_name: str) -> List[str]:
@@ -48,8 +56,9 @@ def web_module_exists(package_name: str) -> bool:
 
 def web_module_names() -> Set[str]:
     names = []
-    for pth in WEB_MODULES_DIR.glob("**/*.js"):
-        rel_pth = pth.relative_to(WEB_MODULES_DIR)
+    web_mod_dir = _web_modules_dir()
+    for pth in web_mod_dir.glob("**/*.js"):
+        rel_pth = pth.relative_to(web_mod_dir)
         if Path("common") in rel_pth.parents:
             continue
         module_path = str(rel_pth.as_posix())
@@ -70,7 +79,7 @@ def add_web_module(package_name: str, source: Union[Path, str]) -> str:
 
 
 def web_module_path(package_name: str, must_exist: bool = False) -> Path:
-    path = WEB_MODULES_DIR.joinpath(*(package_name + ".js").split("/"))
+    path = _web_modules_dir().joinpath(*(package_name + ".js").split("/"))
     if must_exist and not path.exists():
         raise ValueError(
             f"Web module {package_name!r} does not exist at path {str(path)!r}"
@@ -79,7 +88,7 @@ def web_module_path(package_name: str, must_exist: bool = False) -> Path:
 
 
 def restore() -> None:
-    _copy_to_build_dir(BACKUP_BUILD_DIR)
+    _copy_to_build_dir(_BACKUP_BUILD_DIR)
 
 
 def build(packages_to_install: Sequence[str], clean_build: bool = False) -> None:
@@ -92,7 +101,7 @@ def build(packages_to_install: Sequence[str], clean_build: bool = False) -> None
         package_json_path = temp_app_dir / "package.json"
 
         # copy over the whole APP_DIR directory into the temp one
-        shutil.copytree(APP_DIR, temp_app_dir, symlinks=True)
+        shutil.copytree(_APP_DIR, temp_app_dir, symlinks=True)
 
         package_names_to_install = {get_package_name(p) for p in packages_to_install}
 

src/idom/client/manage.py

@@ -1,8 +1,5 @@
-import json
 import re
-from contextlib import contextmanager
-from pathlib import Path
-from typing import Any, Iterator, List, Tuple
+from typing import List, Tuple
 
 
 def get_package_name(pkg: str) -> str:
@@ -24,17 +21,6 @@ def split_package_name_and_version(pkg: str) -> Tuple[str, str]:
         return pkg, ""
 
 
-@contextmanager
-def open_modifiable_json(path: Path) -> Iterator[Any]:
-    with path.open() as f:
-        data = json.loads(f.read().strip() or "{}")
-
-    yield data
-
-    with path.open("w") as f:
-        json.dump(data, f)
-
-
 _JS_MODULE_EXPORT_PATTERN = re.compile(
     r";?\s*export\s*{([0-9a-zA-Z_$\s,]*)}\s*;", re.MULTILINE
 )

src/idom/client/utils.py

@@ -0,0 +1,24 @@
+from pathlib import Path
+
+from ._option import Option
+
+IDOM_DEBUG_MODE = Option(
+    "IDOM_DEBUG_MODE",
+    default=False,
+    allow_changes=False,
+    from_string=lambda x: bool(int(x)),
+)
+"""Turn on/off debug mode"""
+
+IDOM_CLIENT_BUILD_DIR = Option(
+    "IDOM_CLIENT_BUILD_DIR",
+    default=Path(__file__).parent / "client" / "build",
+    from_string=Path,
+)
+"""The location IDOM will use for its client application"""
+
+IDOM_CLIENT_WEB_MODULE_BASE_URL = Option(
+    "IDOM_CLIENT_WEB_MODULE_BASE_URL",
+    default="./_snowpack/pkg",
+)
+"""The base URL where all user-installed web modules reside"""

src/idom/config.py

@@ -18,7 +18,7 @@
 
 from jsonpatch import apply_patch, make_patch
 
-from idom._options import IDOM_DEBUG_MODE
+from idom.config import IDOM_DEBUG_MODE
 
 from .component import AbstractComponent
 from .events import EventHandler, EventTarget
@@ -102,7 +102,7 @@ async def render(self) -> LayoutUpdate:
             if self._has_component_state(component):
                 return self._create_layout_update(component)
 
-    if IDOM_DEBUG_MODE:
+    if IDOM_DEBUG_MODE.get():
         _debug_render = render
 
         @wraps(_debug_render)

src/idom/core/layout.py

@@ -2,7 +2,7 @@
 import sys
 from logging.config import dictConfig
 
-from ._options import IDOM_DEBUG_MODE
+from .config import IDOM_DEBUG_MODE
 
 root_logger = logging.getLogger("idom")
 
@@ -12,7 +12,7 @@
     "disable_existing_loggers": False,
     "loggers": {
         "idom": {
-            "level": "DEBUG" if IDOM_DEBUG_MODE else "INFO",
+            "level": "DEBUG" if IDOM_DEBUG_MODE.get() else "INFO",
             "handlers": ["console"],
         },
     },