From 6ef9711f23f39dbb2dd52af21275110e51cdd011 Mon Sep 17 00:00:00 2001
From: Shish <shish@shishnet.org>
Date: Sun, 15 Nov 2020 11:57:14 +0000
Subject: [PATCH] JSON RPC extension

---
 ext/json_rpc/info.php |  13 ++++++
 ext/json_rpc/main.php | 106 ++++++++++++++++++++++++++++++++++++++++++
 ext/json_rpc/test.php |  12 +++++
 3 files changed, 131 insertions(+)
 create mode 100644 ext/json_rpc/info.php
 create mode 100644 ext/json_rpc/main.php
 create mode 100644 ext/json_rpc/test.php

diff --git a/ext/json_rpc/info.php b/ext/json_rpc/info.php
new file mode 100644
index 00000000..c61608b9
--- /dev/null
+++ b/ext/json_rpc/info.php
@@ -0,0 +1,13 @@
+<?php declare(strict_types=1);
+
+class JsonRpcInfo extends ExtensionInfo
+{
+    public const KEY = "json_rpc";
+
+    public $key = self::KEY;
+    public $name = "JSON RPC API";
+    public $url = self::SHIMMIE_URL;
+    public $authors = self::SHISH_AUTHOR;
+    public $license = self::LICENSE_GPLV2;
+    public $description = "An entry point for a JSON RPC interface";
+}
diff --git a/ext/json_rpc/main.php b/ext/json_rpc/main.php
new file mode 100644
index 00000000..31565617
--- /dev/null
+++ b/ext/json_rpc/main.php
@@ -0,0 +1,106 @@
+<?php
+declare(strict_types=1);
+
+class ApiRequestEvent extends Event
+{
+    public $method;  // string
+    public $params;  // array|object
+    public $id;  // int|string
+    public $result;  // any
+
+    public function __construct(string $method, $params, $id)
+    {
+        parent::__construct();
+        $this->method = $method;
+        $this->params = $params;
+        $this->id = $id;
+        $this->result = null;
+    }
+
+    public static function from_array(array $req)
+    {
+        $method = $req["method"];
+        $params = $req["params"] ?? [];
+        $id = $req["id"];
+        return new ApiRequestEvent($method, $params, $id);
+    }
+}
+
+class JsonRpc extends Extension
+{
+    public function onPageRequest(PageRequestEvent $event)
+    {
+        global $page;
+        if ($event->page_matches("api/json")) {
+            $page->set_mode(PageMode::DATA);
+            $in = json_decode(file_get_contents('php://input'), true);
+
+            // $in is a request
+            if (array_key_exists("jsonrpc", $in)) {
+                $out = $this->get_response($in);
+                if (!is_null($out)) {
+                    $page->set_data(json_encode($out));
+                }
+            }
+            // assume $in is a list of requests
+            else {
+                $out = [];
+                foreach ($in as $req) {
+                    $res = $this->get_response($req);
+                    if (!is_null($res)) {
+                        $out[] = $res;
+                    }
+                }
+                $page->set_data(json_encode($out));
+            }
+        }
+    }
+
+    public function onCommand(CommandEvent $event)
+    {
+        if ($event->cmd == "help") {
+            print "\tjson-rpc <method> <params>\n";
+            print "\t\teg 'json-rpc get-posts'\n\n";
+        }
+        if ($event->cmd == "json-rpc") {
+            print(json_encode($this->get_response([
+                "id" => 1,
+                "method" => $event->args[0],
+                "params" => json_decode($event->args[1] ?? "[]"),
+            ]), JSON_PRETTY_PRINT) . "\n");
+        }
+    }
+
+    private function get_response(array $req): ?array
+    {
+        $evt = ApiRequestEvent::from_array($req);
+        try {
+            send_event($evt);
+            if (is_null($evt->id)) {
+                return null;
+            }
+            return [
+                "jsonrpc" => "2.0",
+                "result" => $evt->result,
+                "id" => $evt->id,
+            ];
+        } catch (Throwable $e) {
+            return [
+                "jsonrpc" => "2.0",
+                "error" => [
+                    "code" => -1,
+                    "message" => $e->getMessage(),
+                    "data" => null,
+                ],
+                "id" => $evt->id,
+            ];
+        }
+    }
+
+    public function onApiRequest(ApiRequestEvent $event)
+    {
+        if ($event->method == "echo") {
+            $event->result = $event->params;
+        }
+    }
+}
diff --git a/ext/json_rpc/test.php b/ext/json_rpc/test.php
new file mode 100644
index 00000000..9749eeea
--- /dev/null
+++ b/ext/json_rpc/test.php
@@ -0,0 +1,12 @@
+<?php declare(strict_types=1);
+
+class JsonRpcTest extends ShimmiePHPUnitTestCase
+{
+    public function testEcho()
+    {
+        $evt = new ApiRequestEvent("echo", ["foo"=>"bar"], 1);
+        send_event($evt);
+        $this->assertEquals(1, $evt->id);
+        $this->assertEquals(["foo"=>"bar"], $evt->result);
+    }
+}