Allow providing manual signature hint to commands

* Add CommandResolverInterface to resolve commands.
* Replace single CommandRegistry with CommandResolverInterface[]
  in CommandBus.
* Make CommandRegistry implement CommandResolverInterface.

LICENSE

@@ -0,0 +1,607 @@
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+To do so, attach the following notices to the program. It is safest to attach
+them to the start of each source file to most effectively state the exclusion of
+warranty; and each file should have at least the “copyright” line and a
+pointer to where the full notice is found.
+
+     <one line to give the program's name and a brief idea of what it does.>
+     Copyright (C) <year>  <name of author>
+
+     This program is free software: you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the Free
+Software Foundation, either version 3 of the License, or (at your option) any
+later version.
+
+     This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+     You should have received a copy of the GNU General Public License along
+with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program does terminal interaction, make it output a short notice like
+this when it starts in an interactive mode:
+
+     <program>  Copyright (C) <year>  <name of author>
+     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+     This is free software, and you are welcome to redistribute it under certain
+conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands might be
+different; for a GUI interface, you would use an “about box”.
+
+You should also get your employer (if you work as a programmer) or school, if
+any, to sign a “copyright disclaimer” for the program, if necessary. For
+more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+The GNU General Public License does not permit incorporating your program into
+proprietary programs. If your program is a subroutine library, you may consider
+it more useful to permit linking proprietary applications with the library. If
+this is what you want to do, use the GNU Lesser General Public License instead
+of this License. But first, please read
+<https://www.gnu.org/philosophy/why-not-lgpl.html>.

Makefile

@@ -0,0 +1,17 @@
+.DEFAULT_GOAL := help
+
+.PHONY: help
+help:
+	@echo "Available Targets:"; grep -E '(^[a-zA-Z_-]+:.*?##.*$$)|(^##)' $(MAKEFILE_LIST) | awk 'BEGIN {FS = ":.*?## "}; {printf "  \033[32m%-20s\033[0m %s\n", $$1, $$2}' | sed -e 's/\[32m##/[33m/'
+
+.PHONY: phpstan
+phpstan: ## Run static analysis
+	@phpstan --no-progress
+
+.PHONY: phpunit
+phpunit: ## Run unit tests
+	@phpunit --testdox --no-progress --display-warnings
+
+.PHONY: coverage
+coverage: ## Code coverage
+	@XDEBUG_MODE=coverage phpunit --coverage-text --no-progress

README.md

@@ -45,3 +45,20 @@ $bus->execute('hello', ['name'=>'Bob'])->then(
     }
 );
 ```
+
+## License
+
+Copyright (C) 2024, NoccyLabs
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.

examples/local.php

@@ -9,6 +9,7 @@ use React\EventLoop\Loop;
 use React\Promise\Promise;
 
 $commands = new CommandRegistry();
+
 // Register some function to call. The name here is "hello", and it will
 // receive a Context holding the call context. Any passed data will be
 // available as properties on the Context object.
@@ -21,23 +22,28 @@ $commands->register("hello", function (Context $context) {
         });
     });
 });
-$commands->register("hello2", function (Context $context) {
+
+// Note how the arguments can be unwrapped. You can still add Context as
+// an argument to get the full context. Values will be cast to match the
+// type, so keep this in mind when feeding strings like 'false' into a
+// boolean argument. It is also a good idea to make the arguments nullable.
+$commands->register("hello2", function (?string $name, ?string $phrase, ?string $missing) {
     // Just returning the value works just fine!
-    return "Hello2, {$context->name}";
+    return "Greetings, {$name}. {$phrase} to you too!";
 });
 
 // Create the bus
 $bus = new CommandBus($commands);
 
 // And execute some commands!
-$bus->execute('hello', ['name'=>'Bob'])->then(
+$bus->execute('hello', ['name'=>'Bob'])
-    function ($result) {
+    ->then(function ($result) {
         var_dump($result);
     }
 );
 
-$bus->execute('hello2', ['name'=>'Bob'])->then(
+$bus->execute('hello2', ['name'=>'Bob','phrase'=>'Good day'])
-    function ($result) {
+    ->then(function ($result) {
         var_dump($result);
     }
 );

phpunit.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/11.0/phpunit.xsd"
+         bootstrap="vendor/autoload.php"
+         cacheDirectory=".phpunit.cache"
+         executionOrder="depends,defects"
+         requireCoverageMetadata="true"
+         beStrictAboutCoverageMetadata="true"
+         beStrictAboutOutputDuringTests="true"
+         failOnRisky="true"
+         failOnWarning="true">
+    <testsuites>
+        <testsuite name="default">
+            <directory>tests</directory>
+        </testsuite>
+    </testsuites>
+
+    <source restrictDeprecations="true" restrictNotices="true" restrictWarnings="true">
+        <include>
+            <directory>src</directory>
+        </include>
+    </source>
+</phpunit>

src/Command.php

@@ -2,6 +2,8 @@
 
 namespace NoccyLabs\React\CommandBus;
 
+use ReflectionFunction;
+use ReflectionNamedType;
 use React\Promise\Deferred;
 use React\Promise\Promise;
 use React\Promise\PromiseInterface;
@@ -17,10 +19,13 @@ class Command
     /** @var callable $handler The handler */
     private $handler;
 
-    public function __construct(string $name, callable $handler)
+    private ?array $signature;
+
+    public function __construct(string $name, callable $handler, ?array $signature = null)
     {
         $this->name = $name;
         $this->handler = $handler;
+        $this->signature = $signature;
     }
 
     public function getName(): string
@@ -31,10 +36,43 @@ class Command
     public function call(Context $context): PromiseInterface
     {
         return new Promise(function (callable $resolve) use ($context) {
-            $resolve(call_user_func($this->handler, $context));
+            $args = $context->toMethodParameters($this->handler);
+            $resolve(call_user_func($this->handler, ...$args));
+            //$resolve(call_user_func($this->handler, $context));
             return;
         });
     }
 
+    public function parameters(): array
+    {
+        $refl = new ReflectionFunction($this->handler);
+        $args = [];
+
+        foreach ($refl->getParameters() as $parameter) {
+            $name = $parameter->getName();
+            $type = null;
+            if (!$parameter->hasType()) {
+                $type = 'any';
+            } else {
+                $type = $parameter->getType();
+                if ($type instanceof ReflectionNamedType && $type->isBuiltin()) {
+                    $type = ($type->allowsNull() ? "?" : "") . $type->getName();
+                } else {
+                    $type = null;
+                }
+            }
+            
+            if ($parameter->isDefaultValueAvailable()) $type = "{$type}=".\json_encode($parameter->getDefaultValue(),\JSON_UNESCAPED_SLASHES);
+            if ($type !== null) $args[$name] = $type;
+        }
+
+        return $args;
+    }
+
+    public function getSignature(): array
+    {
+        return $this->signature ?? $this->parameters();
+    }
+
 }
 

src/CommandBus.php

@@ -13,25 +13,97 @@ class CommandBus implements CommandBusInterface
 {
     use EventEmitterTrait;
 
-    private CommandRegistry $commandRegistry;
+    /** @var array<CommandResolverInterface> */
+    private $resolvers = [];
 
     private SplObjectStorage $connections;
 
     private SplObjectStorage $servers;
 
-    public function __construct(CommandRegistry $commandRegistry)
+    public function __construct(?CommandResolverInterface $commands=null)
     {
-        $this->commandRegistry = $commandRegistry;
+        if ($commands) {
+            $this->resolvers[] = $commands;
+        }
         $this->connections = new SplObjectStorage();
         $this->servers = new SplObjectStorage();
     }
 
+    /**
+     * Get the command registry
+     * 
+     * @deprecated Use getCommandNames() instead
+     * @return null
+     */
+    public function getRegistry(): ?CommandRegistry
+    {
+        return null; // $this->commandRegistry;
+    }
+
+    /**
+     * Add a CommandResolver
+     *
+     * @param CommandResolverInterface $resolver
+     * @return void
+     */
+    public function addResolver(CommandResolverInterface $resolver): void
+    {
+        $this->resolvers[] = $resolver;
+    }
+
+    public function removeResolver(CommandResolverInterface $resolver): void
+    {
+        // FIXME implement
+    }
+
+    /**
+     * Get the names of defined commands
+     *
+     * @return array
+     */
+    public function getCommandNames(): array
+    {
+        $commands = [];
+        foreach ($this->resolvers as $resolver) {
+            $commands = array_merge($commands, $resolver->getCommandNames());
+        }
+        sort($commands);
+        return array_unique($commands);
+    }
+
+    /**
+     * Find a command by searching through the resolvers
+     *
+     * @param string $command
+     * @return Command|null
+     */
+    public function findCommand(string $command): ?Command
+    {
+        foreach ($this->resolvers as $resolver) {
+            if ($found = $resolver->findCommand($command))
+                return $found;
+        }
+        return null;
+    }
+
+    /**
+     * Add a server listener
+     *
+     * @param ServerInterface $server
+     * @return void
+     */
     public function addServer(ServerInterface $server): void
     {
         $this->servers->attach($server);
         $server->on('connection', $this->onServerConnection(...));
     }
 
+    /**
+     * Remove a server listener
+     *
+     * @param ServerInterface $server
+     * @return void
+     */
     public function removeServer(ServerInterface $server): void
     {
         $server->close();
@@ -39,6 +111,11 @@ class CommandBus implements CommandBusInterface
         $this->servers->detach($server);
     }
 
+    /**
+     * Close and shutdown the servers
+     *
+     * @return void
+     */
     public function close(): void
     {
         foreach ($this->servers as $server) {
@@ -101,7 +178,7 @@ class CommandBus implements CommandBusInterface
 
     private function executeContext(Context $context): PromiseInterface
     {
-        $command = $this->commandRegistry->find($context->getCommandName());
+        $command = $this->findCommand($context->getCommandName());
         if (!$command) return new Promise(function (callable $resolve) use ($context) {
             throw new \RuntimeException("Unable to resolve command: ".$context->getCommandName());
         });

src/CommandBusClient.php

@@ -38,8 +38,8 @@ class CommandBusClient implements CommandBusInterface
     {
         $this->commandRegistry = $commandRegistry;
         if ($commandRegistry) {
-            $commandRegistry->on(CommandRegistry::EVENT_REGISTERED, $this->onCommandRegistered(...));
+            $this->commandRegistry->on(CommandRegistry::EVENT_REGISTERED, $this->onCommandRegistered(...));
-            $commandRegistry->on(CommandRegistry::EVENT_UNREGISTERED, $this->onCommandUnregistered(...));
+            $this->commandRegistry->on(CommandRegistry::EVENT_UNREGISTERED, $this->onCommandUnregistered(...));
         }
         $this->connector = $connector??new TcpConnector();
     }
@@ -127,7 +127,7 @@ class CommandBusClient implements CommandBusInterface
                 $this->emit(self::EVENT_NOTIFY, [ $event, $data ]);
                 break;
             case Message::MSGTYPE_ERROR: // error
-                var_dump($message);
+                //var_dump($message);
                 $uuid = $message->getUuid();
                 $error = $message->getData()['error'];
                 if ($uuid && array_key_exists($uuid, $this->pending)) {

src/CommandRegistry.php

@@ -8,7 +8,7 @@ use Evenement\EventEmitterTrait;
  * A collection of commands that can be executed via CommandBusInterface
  *
  */
-class CommandRegistry implements EventEmitterInterface
+class CommandRegistry implements CommandResolverInterface, EventEmitterInterface
 {
     use EventEmitterTrait;
 
@@ -40,12 +40,12 @@ class CommandRegistry implements EventEmitterInterface
         $this->emit(self::EVENT_UNREGISTERED, [ $command ]);
     }
 
-    public function find(string $command): ?Command
+    public function findCommand(string $command): ?Command
     {
         return $this->commands[$command] ?? null;
     }
 
-    public function getNames(): array
+    public function getCommandNames(): array
     {
         return array_keys($this->commands);
     }

src/CommandResolverInterface.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace NoccyLabs\React\CommandBus;
+use Evenement\EventEmitterInterface;
+use Evenement\EventEmitterTrait;
+
+/**
+ * A collection of commands that can be executed via CommandBusInterface
+ *
+ */
+interface CommandResolverInterface
+{
+    
+    public function findCommand(string $command): ?Command;
+
+    public function getCommandNames(): array;
+
+}
+

src/CommandResolverTrait.php

@@ -0,0 +1,52 @@
+<?php
+
+namespace NoccyLabs\React\CommandBus;
+use Evenement\EventEmitterInterface;
+use Evenement\EventEmitterTrait;
+
+/**
+ * A collection of commands that can be executed via CommandBusInterface
+ *
+ */
+trait CommandResolverTrait
+{
+
+    const EVENT_REGISTERED = 'registered';
+    const EVENT_UNREGISTERED = 'unregistered';
+
+    /** @var array<string,Command> */
+    private array $commands = [];
+
+    public function registerCommand(string $command, callable $handler): void
+    {
+        $isNew = !array_key_exists($command, $this->commands);
+
+        $this->commands[$command] = new Command($command, $handler);
+
+        if ($isNew) {
+            $this->emit(self::EVENT_REGISTERED, [ $command ]);
+        }
+    }
+
+    public function unregisterCommand(string $command): void
+    {
+        if (!array_key_exists($command, $this->commands)) {
+            return;
+        }
+
+        unset($this->commands[$command]);
+
+        $this->emit(self::EVENT_UNREGISTERED, [ $command ]);
+    }
+
+    public function findCommand(string $command): ?Command
+    {
+        return $this->commands[$command] ?? null;
+    }
+
+    public function getCommandNames(): array
+    {
+        return array_keys($this->commands);
+    }
+}
+

src/Context.php

@@ -2,6 +2,10 @@
 
 namespace NoccyLabs\React\CommandBus;
 
+use ReflectionFunction;
+use ReflectionIntersectionType;
+use ReflectionNamedType;
+use ReflectionUnionType;
 
 /**
  * The context contains all the data relating to calling a command. It has an
@@ -37,5 +41,55 @@ class Context
     {
         return $this->payload[$name] ?? null;   
     }
+
+    public function toMethodParameters(callable $callable): array
+    {
+        $refl = new ReflectionFunction($callable);
+        $args = [];
+        // Go over the arguments
+        foreach ($refl->getParameters() as $parameter) {
+            $name = $parameter->getName();
+            if (!$parameter->hasType()) {
+                // use name
+                $args[] = isset($this->payload[$name]) 
+                        ? $this->payload[$name] 
+                        : ($parameter->isDefaultValueAvailable() ? $parameter->getDefaultValue() : null);
+            } else {
+                // use name and type
+                $type = $parameter->getType();
+                if ($type instanceof ReflectionNamedType && $type->isBuiltin()) {
+                    $typeName = $type->getName();
+                    $arg = isset($this->payload[$name]) 
+                            ? $this->payload[$name] 
+                            : ($parameter->isDefaultValueAvailable() ? $parameter->getDefaultValue() : null);
+                    $args[] = match ($typeName) {
+                        'string' => strval($arg),
+                        'boolean' => boolval($arg),
+                        'array' => (array)$arg,
+                        'object' => (object)$arg,
+                        'integer' => intval($arg),
+                        'float' => floatval($arg),
+                        default => $arg,
+                    };
+                } elseif ($type instanceof ReflectionNamedType) {
+                    $typeName = $type->getName();
+                    switch ($typeName) {
+                        case Context::class:
+                            $args[] = $this;
+                            break;
+                        default:
+                        $args[] = null; // FIXME how to handle this?
+                    }
+                    
+                } elseif ($type instanceof ReflectionUnionType) {
+                    $args[] = null; // FIXME how to handle this?
+                } elseif ($type instanceof ReflectionIntersectionType) {
+                    $args[] = null; // FIXME how to handle this?
+                }
+                
+            }
+        }
+        return $args;
+    }
 }
 

tests/CommandRegistryTest.php

@@ -0,0 +1,67 @@
+<?php
+
+namespace NoccyLabs\React\CommandBus;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(CommandRegistry::class)]
+class CommandRegistryTest extends \PHPUnit\Framework\TestCase
+{
+
+    public function testAddingNewCommandEmitsEvent()
+    {
+        $count = 0;
+
+        $reg = new CommandRegistry();
+        $reg->on(CommandRegistry::EVENT_REGISTERED, function ($data) use (&$count){
+            $this->assertEquals('foo', $data);
+            $count++;
+        });
+        $reg->register('foo', function () {});
+        $reg->register('foo', function () {});
+
+        $this->assertEquals(1, $count);
+    }
+
+    public function testRemovingCommandEmitsEvent()
+    {
+        $count = 0;
+
+        $reg = new CommandRegistry();
+        $reg->on(CommandRegistry::EVENT_UNREGISTERED, function ($data) use (&$count){
+            $this->assertEquals('foo', $data);
+            $count++;
+        });
+        $reg->register('foo', function () {});
+        $reg->unregister('foo');
+        $reg->unregister('foo');
+
+        $this->assertEquals(1, $count);
+    }
+
+    public function testFindingCommands()
+    {
+        $cmda = function () {};
+        $cmdb = function () {};
+
+        $reg = new CommandRegistry();
+        $reg->register('a', $cmda);
+        $reg->register('b', $cmdb);
+
+        $this->assertEquals('a', $reg->findCommand('a')?->getName());
+        $this->assertEquals('b', $reg->findCommand('b')?->getName());
+    }
+
+    public function testGettingCommandNames()
+    {
+        $cmda = function () {};
+        $cmdb = function () {};
+
+        $reg = new CommandRegistry();
+        $reg->register('a', $cmda);
+        $reg->register('b', $cmdb);
+
+        $this->assertEquals(['a','b'], $reg->getCommandNames());
+    }
+
+}

tests/CommandTest.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace NoccyLabs\React\CommandBus;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(Command::class)]
+class CommandTest extends \PHPUnit\Framework\TestCase
+{
+
+    public function testCommandName()
+    {
+        $command = new Command("foobar", function () {});
+
+        $this->assertEquals('foobar', $command->getName());
+    }
+
+    public function testCommandExecution()
+    {
+        $hit = false;
+        $command = new Command("foobar", function () use (&$hit) { $hit=true; });
+        $context = new Context("foobar", []);
+
+        $command->call($context);
+
+        $this->assertEquals(true, $hit);
+    }
+
+    public function testCommandReflection()
+    {
+        $command = new Command("test", function (string $a, ?int $b, bool $c = false) { });
+        $expect = [
+            'a' => 'string',
+            'b' => '?int',
+            'c' => 'bool=false'
+        ];
+        $this->assertEquals($expect, $command->parameters());
+    }
+}

tests/ContextTest.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace NoccyLabs\React\CommandBus;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+
+#[CoversClass(Context::class)]
+class ContextTest extends \PHPUnit\Framework\TestCase
+{
+
+    public function testContextPropertyAccess()
+    {
+        $context = new Context("", [ 'foo'=>true, 'bar'=>'hello' ]);
+
+        $this->assertEquals(true, $context->foo);
+        $this->assertEquals('hello', $context->bar);
+    }
+
+    public function testMakingParameters()
+    {
+        $func1 = function () {};
+        $func2 = function (Context $context) {};
+        $func3 = function ($a, ?int $b, ?string $c, $d) {};
+
+        $context = new Context("", [ 'a'=>true, 'b'=>42, 'c'=>'hello' ]);
+
+        $expect1 = [];
+        $expect2 = [$context];
+        $expect3 = [true,42,'hello',null];
+
+        $args1 = $context->toMethodParameters($func1);
+        $this->assertEquals($expect1, $args1);
+
+        $args2 = $context->toMethodParameters($func2);
+        $this->assertEquals($expect2, $args2);
+
+        $args3 = $context->toMethodParameters($func3);
+        $this->assertEquals($expect3, $args3);
+    }
+}