feat: Improved handle_on alternative #1484. (#2113)

client.go

@@ -46,7 +46,8 @@ var (
 // BootMsg represents the initial message sent to an app when a client first connects to it.
 type BootMsg struct {
 	Data struct {
-		Hash string `json:"#,omitempty"` // location hash
+		Hash           string `json:"#,omitempty"`                        // location hash
+		SubmissionName string `json:"__wave_submission_name__,omitempty"` // mark the cause of the serve invocation
 	} `json:"data"`
 	Headers http.Header `json:"headers"` // forwarded headers
 }
@@ -171,6 +172,7 @@ func (c *Client) listen() {
 
 				if len(m.data) > 0 { // location hash
 					boot.Data.Hash = string(m.data)
+					boot.Data.SubmissionName = "#"
 				}
 
 				body, err := json.Marshal(boot)

py/examples/hash_routing_parameters.py

@@ -2,7 +2,7 @@
 # Use the browser's [location hash](https://developer.mozilla.org/en-US/docs/Web/API/Location/hash)
 # for #routing using URLs, with parameters.
 # ---
-from h2o_wave import main, app, Q, ui, on, handle_on
+from h2o_wave import main, app, Q, ui, on, run_on
 
 air_passengers_fields = ['Year', 'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun']
 air_passengers_rows = [
@@ -62,6 +62,6 @@ async def serve(q: Q):
             content='Click on a cell in the table above!',
         )
 
-    await handle_on(q)
+    await run_on(q)
 
     await q.page.save()

py/examples/plot_events_routing.py

@@ -1,7 +1,7 @@
 # Plot / Events / Routing
 # Handle #events on a #plot card using routing.
 # ---
-from h2o_wave import main, app, on, handle_on, Q, ui, data
+from h2o_wave import main, app, on, run_on, Q, ui, data
 
 
 @on('pricing.select_marks')
@@ -32,4 +32,4 @@ async def serve(q: Q):
         )
         await q.page.save()
     else:
-        await handle_on(q)
+        await run_on(q)

py/examples/routing.py

@@ -1,7 +1,7 @@
 # Routing
-# Use `on` and `handle_on` to simplify query handling by #routing queries to designated functions.
+# Use `on` and `run_on` to simplify query handling by #routing queries to designated functions.
 # ---
-from h2o_wave import main, app, Q, ui, on, handle_on
+from h2o_wave import main, app, Q, ui, on, run_on
 
 
 # This function is called when q.args['empty_cart'] is True.
@@ -60,4 +60,4 @@ async def serve(q: Q):
             ],
         )
         await q.page.save()
-    await handle_on(q)
+    await run_on(q)

py/examples/routing_predicates.py

@@ -1,7 +1,7 @@
 # Routing / Predicates
-# Use `on` and `handle_on` with predicates to handle routing with custom conditions.
+# Use `on` and `run_on` with predicates to handle routing with custom conditions.
 # ---
-from h2o_wave import main, app, Q, ui, on, handle_on
+from h2o_wave import main, app, Q, ui, on, run_on
 
 
 # This function is called when q.args['temperature'] < 15.
@@ -29,7 +29,7 @@ async def serve(q: Q):
         q.args.temperature = 20
         await show_slider(q, "")
     else:
-        await handle_on(q)
+        await run_on(q)
 
 
 async def show_slider(q: Q, message: str):

py/examples/tour.py

@@ -14,7 +14,7 @@
 from typing import Dict, List, Optional, Tuple
 from urllib.parse import urlparse
 
-from h2o_wave import Q, app, handle_on, main, on, ui
+from h2o_wave import Q, app, run_on, main, on, ui
 
 example_dir = os.path.dirname(os.path.realpath(__file__))
 tour_tmp_dir = os.path.join(example_dir, '_tour_apps_tmp')
@@ -416,7 +416,7 @@ async def serve(q: Q):
         q.client.path = uuid.uuid4()
         await setup_page(q)
 
-    await handle_on(q)
+    await run_on(q)
 
     search = q.args[q.args['#'] or default_example_name]
     if search and not q.events.editor:

py/h2o_lightwave/h2o_lightwave/__init__.py

@@ -23,7 +23,7 @@
 
 from .core import Ref, data, pack, Expando, expando_to_dict, clone_expando, copy_expando
 from .server import Q, wave_serve
-from .routing import on, handle_on
+from .routing import on, run_on, handle_on
 from .types import *
 from .version import __version__
 

py/h2o_lightwave/h2o_lightwave/routing.py

@@ -14,7 +14,6 @@
 
 from typing import Optional, Callable
 from inspect import signature
-import asyncio
 import logging
 from starlette.routing import compile_path
 from .core import expando_to_dict
@@ -25,6 +24,8 @@
 _event_handlers = {}  # dictionary of event_source => [(event_type, predicate, handler)]
 _arg_handlers = {}  # dictionary of arg_name => [(predicate, handler)]
 _path_handlers = []
+_arg_with_params_handlers = []
+_handle_on_deprecated_warning_printed = False
 
 
 def _get_arity(func: Callable) -> int:
@@ -86,9 +87,8 @@ def wrap(func):
         # if not asyncio.iscoroutinefunction(func):
         #    raise ValueError(f"@on function '{func_name}' must be async")
 
-        if predicate:
-            if not callable(predicate):
-                raise ValueError(f"@on predicate must be callable for '{func_name}'")
+        if predicate and not callable(predicate):
+            raise ValueError(f"@on predicate must be callable for '{func_name}'")
         if isinstance(arg, str) and len(arg):
             if arg.startswith('#'):  # location hash
                 rx, _, conv = compile_path(arg[1:])
@@ -100,6 +100,9 @@ def wrap(func):
                 if not len(event):
                     raise ValueError(f"@on event type cannot be empty in '{arg}' for '{func_name}'")
                 _add_event_handler(source, event, func, predicate)
+            elif "{" in arg and "}" in arg:
+                rx, _, conv = compile_path(arg)
+                _arg_with_params_handlers.append((predicate, func, _get_arity(func), rx, conv))
             else:
                 _add_handler(arg, func, predicate)
         else:
@@ -110,28 +113,32 @@ def wrap(func):
     return wrap
 
 
-async def _invoke_handler(func: Callable, arity: int, q: Q, arg: any):
+async def _invoke_handler(func: Callable, arity: int, q: Q, arg: any, **params: any):
     if arity == 0:
         await func()
     elif arity == 1:
         await func(q)
-    else:
+    elif len(params) == 0:
         await func(q, arg)
+    elif arity == len(params) + 1:
+        await func(q, **params)
+    else:
+        await func(q, arg, **params)
 
 
-async def _match_predicate(predicate: Callable, func: Callable, arity: int, q: Q, arg: any) -> bool:
+async def _match_predicate(predicate: Callable, func: Callable, arity: int, q: Q, arg: any, **params: any) -> bool:
     if predicate:
         if predicate(arg):
-            await _invoke_handler(func, arity, q, arg)
+            await _invoke_handler(func, arity, q, arg, **params)
             return True
     else:
-        if arg:
-            await _invoke_handler(func, arity, q, arg)
+        if arg is not None:
+            await _invoke_handler(func, arity, q, arg, **params)
             return True
     return False
 
 
-async def handle_on(q: Q) -> bool:
+async def run_on(q: Q) -> bool:
     """
     Handle the query using a query handler (a function annotated with `@on()`).
 
@@ -141,6 +148,67 @@ async def handle_on(q: Q) -> bool:
     Returns:
         True if a matching query handler was found and invoked, else False.
     """
+    submitted = str(q.args['__wave_submission_name__'])
+
+    # Event handlers.
+    for event_source in expando_to_dict(q.events):
+        for entry in _event_handlers.get(event_source, []):
+            event_type, predicate, func, arity = entry
+            event = q.events[event_source]
+            if event_type in event:
+                arg_value = event[event_type]
+                if await _match_predicate(predicate, func, arity, q, arg_value):
+                    return True
+
+    # Hash handlers.
+    if submitted == '#':
+        for rx, conv, func, arity in _path_handlers:
+            match = rx.match(q.args[submitted])
+            if match:
+                params = match.groupdict()
+                for key, value in params.items():
+                    params[key] = conv[key].convert(value)
+                if len(params):
+                    if arity <= 1:
+                        await _invoke_handler(func, arity, q, None)
+                    else:
+                        await func(q, **params)
+                else:
+                    await _invoke_handler(func, arity, q, None)
+                return True
+
+    # Arg handlers.
+    for entry in _arg_handlers.get(submitted, []):
+        predicate, func, arity = entry
+        if await _match_predicate(predicate, func, arity, q, q.args[submitted]):
+            return True
+    for predicate, func, arity, rx, conv in _arg_with_params_handlers:
+        match = rx.match(submitted)
+        if match:
+            params = match.groupdict()
+            for key, value in params.items():
+                params[key] = conv[key].convert(value)
+            if await _match_predicate(predicate, func, arity, q, q.args[submitted], **params):
+                return True
+
+    return False
+
+
+async def handle_on(q: Q) -> bool:
+    """
+    DEPRECATED: Handle the query using a query handler (a function annotated with `@on()`).
+
+    Args:
+        q: The query context.
+
+    Returns:
+        True if a matching query handler was found and invoked, else False.
+    """
+    global _handle_on_deprecated_warning_printed
+    if not _handle_on_deprecated_warning_printed:
+        print('\033[93m' + 'WARNING: handle_on() is deprecated, use run_on() instead.' + '\033[0m')
+        _handle_on_deprecated_warning_printed = True
+
     event_sources = expando_to_dict(q.events)
     for event_source in event_sources:
         event = q.events[event_source]

py/h2o_wave/h2o_wave/__init__.py

@@ -31,7 +31,7 @@
 """
 from .core import Site, AsyncSite, site, Page, Ref, data, pack, Expando, expando_to_dict, clone_expando, copy_expando
 from .server import Q, app, main
-from .routing import on, handle_on
+from .routing import on, handle_on, run_on
 from .db import connect, WaveDBConnection, WaveDB, WaveDBError
 from .types import *
 from .test import cypress, Cypress

py/h2o_wave/h2o_wave/cli.py

@@ -147,17 +147,17 @@ def run(app: str, no_reload: bool, no_autostart: bool):
     else:
         autostart = os.environ.get('H2O_WAVE_NO_AUTOSTART', 'false').lower() in ['false', '0', 'f']
 
-    waved = 'waved.exe' if IS_WINDOWS else './waved'
+    waved_path = os.path.join(sys.exec_prefix, 'waved.exe' if IS_WINDOWS else 'waved')
     # OS agnostic wheels do not include waved - needed for HAC.
-    is_waved_present = os.path.isfile(os.path.join(sys.exec_prefix, waved))
+    is_waved_present = os.path.isfile(waved_path)
 
     try:
         if autostart and is_waved_present and server_not_running:
             kwargs = {}
             if IS_WINDOWS:
                 kwargs['creationflags'] = subprocess.CREATE_NEW_PROCESS_GROUP
 
-            waved_process = subprocess.Popen([waved], cwd=sys.exec_prefix, env=os.environ.copy(), **kwargs)
+            waved_process = subprocess.Popen([waved_path], cwd=sys.exec_prefix, env=os.environ.copy(), **kwargs)
             time.sleep(1)
             server_not_running = _scan_free_port(server_port) == server_port
             retries = 3
@@ -166,21 +166,22 @@ def run(app: str, no_reload: bool, no_autostart: bool):
                 time.sleep(2)
                 server_not_running = _scan_free_port(server_port) == server_port
                 retries = retries - 1
-    finally:
+
         if autostart and server_not_running:
             print('Could not connect to Wave server. Please start the Wave server (waved or waved.exe) prior to running any app.')
             return
-        try:
-            if not os.environ.get('H2O_WAVE_WAVED_DIR') and is_waved_present:
-                os.environ['H2O_WAVE_WAVED_DIR'] = sys.exec_prefix
-            reload_exclude = os.environ.get('H2O_WAVE_RELOAD_EXCLUDE', None)
-            if reload_exclude:
-                reload_exclude = reload_exclude.split(os.pathsep)
-            uvicorn.run(f'{app}:main', host=host, port=port, reload=not no_reload, reload_excludes=reload_exclude)
-        except Exception as e:
-            if waved_process:
-                waved_process.kill()
-            raise e
+
+        if not os.environ.get('H2O_WAVE_WAVED_DIR') and is_waved_present:
+            os.environ['H2O_WAVE_WAVED_DIR'] = sys.exec_prefix
+        reload_exclude = os.environ.get('H2O_WAVE_RELOAD_EXCLUDE', None)
+        if reload_exclude:
+            reload_exclude = reload_exclude.split(os.pathsep)
+        uvicorn.run(f'{app}:main', host=host, port=port, reload=not no_reload, reload_excludes=reload_exclude)
+    except Exception as e:
+        raise e
+    finally:
+        if waved_process:
+            waved_process.kill()
 
 
 @main.command()