Watch dotenvs and automatically refreshing

docs/CHANGELOG.md

@@ -1,10 +1,16 @@
 ## 1.13.0 [8th September 2024]
 
+### Added
+
+- New `collection_browser.show_on_startup` config to control whether the collection browser is shown on startup.
+- Watch for changes to loaded dotenv files and reload UI elements that depend on them when they change.
+
 ### Changed
 
 - Upgraded all dependencies
 - Remove `pydantic-settings` crash workaround on empty config files.
 - Renaming `App.maximized` as it now clashes with a Textual concept.
+- Removed "using default collection" message from startup.
 
 ### Fixed
 

docs/guide/configuration.md

@@ -110,6 +110,7 @@ The table below lists all available configuration options and their environment
 | `theme_directory` (`POSTING_THEME_DIRECTORY`) | (Default: `${XDG_DATA_HOME}/posting/themes`) | The directory containing user themes. |
 | `layout` (`POSTING_LAYOUT`) | `"vertical"`, `"horizontal"` (Default: `"horizontal"`) | Sets the layout of the application. |
 | `use_host_environment` (`POSTING_USE_HOST_ENVIRONMENT`) | `true`, `false` (Default: `false`) | Allow/deny using environment variables from the host machine in requests via `$env:` syntax. When disabled, only variables defined explicitly in `.env` files will be available for use. |
+| `watch_env_files` (`POSTING_WATCH_ENV_FILES`) | `true`, `false` (Default: `true`) | If enabled, automatically reload environment files when they change. |
 | `animation` (`POSTING_ANIMATION`) | `"none"`, `"basic"`, `"full"` (Default: `"none"`) | Controls the animation level. |
 | `response.prettify_json` (`POSTING_RESPONSE__PRETTIFY_JSON`) | `true`, `false` (Default: `true`) | If enabled, JSON responses will be pretty-formatted. |
 | `response.show_size_and_time` (`POSTING_RESPONSE__SHOW_SIZE_AND_TIME`) | `true`, `false` (Default: `true`) | If enabled, the size and time taken for the response will be displayed in the response area border subtitle. |
@@ -118,6 +119,7 @@ The table below lists all available configuration options and their environment
 | `heading.show_version` (`POSTING_HEADING__SHOW_VERSION`) | `true`, `false` (Default: `true`) | Show/hide the version in the app header. |
 | `url_bar.show_value_preview` (`POSTING_URL_BAR__SHOW_VALUE_PREVIEW`) | `true`, `false` (Default: `true`) | Show/hide the variable value preview below the URL bar. |
 | `collection_browser.position` (`POSTING_COLLECTION_BROWSER__POSITION`) | `"left"`, `"right"` (Default: `"left"`) | The position of the collection browser on screen. |
+| `collection_browser.show_on_startup` (`POSTING_COLLECTION_BROWSER__SHOW_ON_STARTUP`) | `true`, `false` (Default: `true`) | Show/hide the collection browser on startup. Can always be toggled using the command palette. |
 | `pager` (`POSTING_PAGER`) | (Default: `$PAGER`) | Command to use for paging text. |
 | `pager_json` (`POSTING_PAGER_JSON`) | (Default: `$PAGER`) | Command to use for paging JSON. |
 | `editor` (`POSTING_EDITOR`) | (Default: `$EDITOR`) | Command to use for opening files in an external editor. |

docs/guide/index.md

@@ -49,7 +49,7 @@ This introduction will show you how to create a simple POST request to the [JSON
 
 A *collection* is simply a directory which may contain requests saved by Posting.
 
-If you launch Posting without specifying a collection, any requests you create will be saved in the "default" collection.
+If you launch Posting without specifying a collection, any requests you create will be saved in the `"default"` collection.
 This is a directory reserved by Posting on your filesystem, and unrelated to the directory you launched Posting from.
 
 This is fine for quick throwaway requests, but you'll probably want to create a new collection for each project you work on so that you can check it into version control.

pyproject.toml

@@ -17,6 +17,7 @@ dependencies = [
     "python-dotenv==1.0.1",
     "textual[syntax]==0.79.1",
     "textual-autocomplete==3.0.0a9",
+    "watchfiles>=0.24.0",
 ]
 readme = "README.md"
 requires-python = ">= 3.11"

src/posting/__main__.py

@@ -1,3 +1,4 @@
+import asyncio
 from pathlib import Path
 import click
 
@@ -13,6 +14,7 @@
     default_collection_directory,
     theme_directory,
 )
+from posting.variables import load_variables
 
 
 def create_config_file() -> None:
@@ -132,5 +134,6 @@ def make_posting(
 
     env_paths = tuple(Path(e).resolve() for e in env)
     settings = Settings(_env_file=env_paths)  # type: ignore[call-arg]
+    asyncio.run(load_variables(env_paths, settings.use_host_environment))
 
     return Posting(settings, env_paths, collection_tree, not using_default_collection)

src/posting/app.py

@@ -23,6 +23,7 @@
 )
 from textual.widgets._tabbed_content import ContentTab
 from textual.widgets.text_area import TextAreaTheme
+from watchfiles import awatch
 from posting.collection import (
     Collection,
     Cookie,
@@ -145,7 +146,6 @@ def __init__(
         self._initial_layout: PostingLayout = layout
         self.environment_files = environment_files
         self.settings = SETTINGS.get()
-        load_variables(self.environment_files, self.settings.use_host_environment)
 
     def on_mount(self) -> None:
         self.layout = self._initial_layout
@@ -168,7 +168,11 @@ def compose(self) -> ComposeResult:
         yield AppHeader()
         yield UrlBar()
         with AppBody():
-            yield CollectionBrowser(collection=self.collection)
+            collection_browser = CollectionBrowser(collection=self.collection)
+            collection_browser.display = (
+                self.settings.collection_browser.show_on_startup
+            )
+            yield collection_browser
             yield RequestEditor()
             yield ResponseArea()
         yield Footer(show_command_palette=False)
@@ -628,10 +632,26 @@ def __init__(
         self.collection = collection
         self.collection_specified = collection_specified
         self.animation_level = settings.animation
+        self.env_changed_signal = Signal[None](self, "env-changed")
 
     theme: Reactive[str] = reactive("galaxy", init=False)
     _jumping: Reactive[bool] = reactive(False, init=False, bindings=True)
 
+    @work(exclusive=True, group="environment-watcher")
+    async def watch_environment_files(self) -> None:
+        async for changes in awatch(*self.environment_files):
+            await load_variables(
+                self.environment_files,
+                self.settings.use_host_environment,
+                avoid_cache=True,
+            )
+            self.env_changed_signal.publish(None)
+            self.notify(
+                title="Environment changed",
+                message=f"Reloaded {len(changes)} dotenv files",
+                timeout=3,
+            )
+
     def on_mount(self) -> None:
         self.jumper = Jumper(
             {
@@ -653,20 +673,15 @@ def on_mount(self) -> None:
         )
         self.theme_change_signal = Signal[Theme](self, "theme-changed")
         self.theme = self.settings.theme
+        if self.settings.watch_env_files:
+            self.watch_environment_files()
 
     def get_default_screen(self) -> MainScreen:
         self.main_screen = MainScreen(
             collection=self.collection,
             layout=self.settings.layout,
             environment_files=self.environment_files,
         )
-        if not self.collection_specified:
-            self.notify(
-                "Using the default collection directory.",
-                title="No collection specified",
-                severity="warning",
-                timeout=7,
-            )
         return self.main_screen
 
     def get_css_variables(self) -> dict[str, str]:

src/posting/commands.py

@@ -45,28 +45,28 @@ def commands(
 
             # Change the available commands depending on what is currently
             # maximized on the main screen.
-            maximized = screen.maximized
             reset_command = (
                 "view: reset",
-                partial(screen.maximize_section, None),
+                partial(screen.expand_section, None),
                 "Reset section sizes to default",
                 True,
             )
             expand_request_command = (
                 "view: expand request",
-                partial(screen.maximize_section, "request"),
+                partial(screen.expand_section, "request"),
                 "Expand the request section",
                 True,
             )
             expand_response_command = (
                 "view: expand response",
-                partial(screen.maximize_section, "response"),
+                partial(screen.expand_section, "response"),
                 "Expand the response section",
                 True,
             )
-            if maximized == "request":
+            expanded_section = screen.expanded_section
+            if expanded_section == "request":
                 commands_to_show.extend([reset_command, expand_response_command])
-            elif maximized == "response":
+            elif expanded_section == "response":
                 commands_to_show.extend([reset_command, expand_request_command])
             else:
                 commands_to_show.extend(

src/posting/config.py

@@ -89,6 +89,9 @@ class CollectionBrowserSettings(BaseModel):
     position: Literal["left", "right"] = Field(default="left")
     """The position of the collection browser on screen."""
 
+    show_on_startup: bool = Field(default=True)
+    """If enabled, the collection browser will be shown on startup."""
+
 
 class Settings(BaseSettings):
     model_config = SettingsConfigDict(
@@ -122,6 +125,9 @@ class Settings(BaseSettings):
     using the `${VARIABLE_NAME}` syntax. When disabled, you are restricted to variables
     defined in any `.env` files explicitly supplied via the `--env` option."""
 
+    watch_env_files: bool = Field(default=True)
+    """If enabled, automatically reload environment files when they change."""
+
     text_input: TextInputSettings = Field(default_factory=TextInputSettings)
     """General configuration for inputs and text area widgets."""
 

src/posting/variables.py

@@ -6,31 +6,45 @@
 import os
 from pathlib import Path
 from dotenv import dotenv_values
+from asyncio import Lock
 
 
 _VARIABLES_PATTERN = re.compile(
     r"\$(?:([a-zA-Z_][a-zA-Z0-9_]*)|{([a-zA-Z_][a-zA-Z0-9_]*)})"
 )
 
-_initial_variables: dict[str, str | None] = {}
-VARIABLES: ContextVar[dict[str, str | None]] = ContextVar(
-    "variables", default=_initial_variables
-)
+
+class SharedVariables:
+    def __init__(self):
+        self._variables: dict[str, str | None] = {}
+        self._lock = Lock()
+
+    def get(self) -> dict[str, str | None]:
+        return self._variables.copy()
+
+    async def set(self, variables: dict[str, str | None]) -> None:
+        async with self._lock:
+            self._variables = variables
+
+
+VARIABLES = SharedVariables()
 
 
 def get_variables() -> dict[str, str | None]:
     return VARIABLES.get()
 
 
-def load_variables(
-    environment_files: tuple[Path, ...], use_host_environment: bool
+async def load_variables(
+    environment_files: tuple[Path, ...],
+    use_host_environment: bool,
+    avoid_cache: bool = False,
 ) -> dict[str, str | None]:
     """Load the variables that are currently available in the environment.
 
     This will make them available via the `get_variables` function."""
 
-    existing_variables = VARIABLES.get()
-    if existing_variables:
+    existing_variables = get_variables()
+    if existing_variables and not avoid_cache:
         return {key: value for key, value in existing_variables}
 
     variables: dict[str, str | None] = {
@@ -42,7 +56,7 @@ def load_variables(
         host_env_variables = {key: value for key, value in os.environ.items()}
         variables = {**variables, **host_env_variables}
 
-    VARIABLES.set(variables)
+    await VARIABLES.set(variables)
     return variables
 
 
@@ -162,6 +176,7 @@ def get_variable_at_cursor(cursor: int, text: str) -> str | None:
     return text[start:end]
 
 
+@lru_cache()
 def extract_variable_name(variable_text: str) -> str:
     """
     Extract the variable name from a variable reference.

src/posting/widgets/request/url_bar.py

@@ -152,6 +152,10 @@ def __init__(
         self.cached_base_urls: list[str] = []
         self._trace_events: set[Event] = set()
 
+    def on_env_changed(self, _: None) -> None:
+        self._display_variable_at_cursor()
+        self.url_input.refresh()
+
     def compose(self) -> ComposeResult:
         with Horizontal():
             yield MethodSelector(id="method-selector")
@@ -161,6 +165,7 @@ def compose(self) -> ComposeResult:
             )
             yield Label(id="trace-markers")
             yield SendRequestButton("Send")
+
         variable_value_bar = Label(id="variable-value-bar")
         if SETTINGS.get().url_bar.show_value_preview:
             yield variable_value_bar
@@ -175,19 +180,34 @@ def on_mount(self) -> None:
 
         self.on_theme_change(self.app.themes[self.app.theme])
         self.app.theme_change_signal.subscribe(self, self.on_theme_change)
+        self.app.env_changed_signal.subscribe(self, self.on_env_changed)
 
     @on(Input.Changed)
     def on_change(self, event: Input.Changed) -> None:
-        self.variable_value_bar.update("")
+        try:
+            self.variable_value_bar.update("")
+        except NoMatches:
+            return
 
     @on(UrlInput.Blurred)
     def on_blur(self, event: UrlInput.Blurred) -> None:
-        self.variable_value_bar.update("")
+        try:
+            self.variable_value_bar.update("")
+        except NoMatches:
+            return
 
     @on(UrlInput.CursorMoved)
     def on_cursor_moved(self, event: UrlInput.CursorMoved) -> None:
+        self._display_variable_at_cursor()
+
+    def _display_variable_at_cursor(self) -> None:
+        url_input = self.url_input
+
+        cursor_position = url_input.cursor_position
+        value = url_input.value
+        variable_at_cursor = get_variable_at_cursor(cursor_position, value)
+
         variables = get_variables()
-        variable_at_cursor = get_variable_at_cursor(event.cursor_position, event.value)
         try:
             variable_bar = self.variable_value_bar
         except NoMatches:

src/posting/widgets/variable_input.py

@@ -1,6 +1,10 @@
+from textual import on
+from textual.widgets import Input
+from textual_autocomplete import DropdownItem, TargetState
 from posting.help_screen import HelpData
 from posting.highlighters import VariableHighlighter
 from posting.themes import Theme
+from posting.variables import get_variables
 from posting.widgets.input import PostingInput
 
 from posting.widgets.variable_autocomplete import VariableAutoComplete
@@ -22,12 +26,11 @@ def on_mount(self) -> None:
         self.highlighter = VariableHighlighter()
         self.auto_complete = VariableAutoComplete(
             candidates=[],
+            variable_candidates=self._get_variable_candidates,
             target=self,
         )
         self.screen.mount(self.auto_complete)
 
-        # Trigger the callback to set the initial highlighter
-
     def on_theme_change(self, theme: Theme) -> None:
         """Callback which fires when the app-level theme changes in order
         to update the color scheme of the variable highlighter.
@@ -39,3 +42,6 @@ def on_theme_change(self, theme: Theme) -> None:
         if theme.variable:
             self.highlighter.variable_styles = theme.variable.fill_with_defaults(theme)
             self.refresh()
+
+    def _get_variable_candidates(self, target_state: TargetState) -> list[DropdownItem]:
+        return [DropdownItem(main=f"${variable}") for variable in get_variables()]

tests/sample-configs/custom_theme.yaml

@@ -8,3 +8,5 @@ heading:
   show_version: false
 text_input:
   blinking_cursor: false
+watch_env_files: false
+

tests/sample-configs/custom_theme2.yaml

@@ -8,3 +8,4 @@ heading:
   show_version: false
 text_input:
   blinking_cursor: false
+watch_env_files: false

tests/sample-configs/general.yaml

@@ -7,3 +7,4 @@ heading:
   show_version: false
 text_input:
   blinking_cursor: false
+watch_env_files: false

tests/sample-configs/modified_config.yaml

@@ -10,4 +10,5 @@ focus:
 heading:
   visible: false
 text_input:
-  blinking_cursor: false
+  blinking_cursor: false
+watch_env_files: false