Added query_global_state rpc call

Signed-off-by: Roman Bylbas <romka.bulbas@gmail.com>

Author: Roman Bylbas

docs/API/RpcClientAPI.md

@@ -204,3 +204,20 @@ Returns an item from a Dictionary ([StoredValue](../Entity/StoredValue.md) objec
 | `$stateRootHash` | `string` | Hex-encoded hash of the state root | Yes |
 | `$dictionaryItemKey` | `string` | The dictionary item key formatted as a string | Yes |
 | `$seedUref` | `string` | The dictionary's seed URef | Yes |
+
+---
+## Get global state
+```php
+getGlobalState(
+    string $blockHash,
+    string $key,
+    array $path
+): GlobalState
+```
+Returns an [GlobalState](../Entity/GlobalState.md) object by the given block hash and key
+### Parameters
+| Name | Type | Description | Required |
+|---|------|-------------|----|
+| `$blockHash` | `string` | Hex-encoded hash of the block | Yes |
+| `$key` | `string` | `casper_types::Key` as formatted string | Yes |
+| `$path` | `array` | The path components starting from the key as base | No |

docs/Entity/GlobalState.md

@@ -0,0 +1,12 @@
+# GlobalState
+
+```php
+getBlockHeader(): BlockHeader
+```
+Returns [BlockHeader](BlockHeader.md) object
+
+---
+```php
+getStoredValue(): StoredValue
+```
+Returns [StoredValue](StoredValue.md) object

src/Entity/GlobalState.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace Casper\Entity;
+
+class GlobalState
+{
+    private BlockHeader $blockHeader;
+
+    private StoredValue $storedValue;
+
+    public function __construct(BlockHeader $blockHeader, StoredValue $storedValue)
+    {
+        $this->blockHeader = $blockHeader;
+        $this->storedValue = $storedValue;
+    }
+
+    public function getBlockHeader(): BlockHeader
+    {
+        return $this->blockHeader;
+    }
+
+    public function getStoredValue(): StoredValue
+    {
+        return $this->storedValue;
+    }
+}

src/Rpc/RpcClient.php

@@ -8,6 +8,7 @@
 use Casper\Serializer\CLPublicKeySerializer;
 use Casper\Serializer\CLURefSerializer;
 use Casper\Serializer\EraSummarySerializer;
+use Casper\Serializer\GlobalStateSerializer;
 use Casper\Serializer\PeerSerializer;
 use Casper\Serializer\BlockSerializer;
 use Casper\Serializer\DeploySerializer;
@@ -24,6 +25,7 @@
 use Casper\Entity\Block;
 use Casper\Entity\Deploy;
 use Casper\Entity\EraSummary;
+use Casper\Entity\GlobalState;
 use Casper\Entity\Peer;
 use Casper\Entity\Status;
 use Casper\Entity\StoredValue;
@@ -50,6 +52,7 @@ class RpcClient
     private const RPC_METHOD_GET_ACCOUNT_BALANCE = 'state_get_balance';
     private const RPC_METHOD_GET_ERA_INFO_BY_SWITCH_BLOCK = 'chain_get_era_info_by_switch_block';
     private const RPC_METHOD_GET_DICTIONARY_ITEM = 'state_get_dictionary_item';
+    private const RPC_METHOD_QUERY_GLOBAL_STATE = 'query_global_state';
 
     private string $nodeUrl;
 
@@ -348,6 +351,25 @@ public function getDictionaryItemByURef(
         return StoredValueSerializer::fromJson($response['stored_value']);
     }
 
+    /**
+     * @throws RpcError
+     */
+    public function getGlobalState(string $blockHash, string $key, array $path = []): GlobalState
+    {
+        $response = $this->rpcCallMethod(
+            self::RPC_METHOD_QUERY_GLOBAL_STATE,
+            array(
+                'state_identifier' => array(
+                    'BlockHash' => $blockHash
+                ),
+                'key' => $key,
+                'path' => $path,
+            )
+        );
+
+        return GlobalStateSerializer::fromJson($response);
+    }
+
     /**
      * @throws RpcError
      */

src/Serializer/GlobalStateSerializer.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace Casper\Serializer;
+
+use Casper\Entity\GlobalState;
+
+class GlobalStateSerializer extends JsonSerializer
+{
+    /**
+     * @param GlobalState $globalState
+     */
+    public static function toJson($globalState): array
+    {
+        return array(
+            'node_id' => BlockHeaderSerializer::toJson($globalState->getBlockHeader()),
+            'address' => StoredValueSerializer::toJson($globalState->getStoredValue()),
+        );
+    }
+
+    public static function fromJson(array $json): GlobalState
+    {
+        return new GlobalState(
+            BlockHeaderSerializer::fromJson($json['block_header']),
+            StoredValueSerializer::fromJson($json['stored_value'])
+        );
+    }
+}

tests/Functional/Rpc/RpcClientTest.php

@@ -240,4 +240,13 @@ public function testGetEraSummaryBySwitchBlockHeight(): void
         $this->assertEquals('de8649985929090b7cb225e35a5a7b4087fb8fcb3d18c8c9a58da68e4eda8a2e', strtolower($eraSummary->getBlockHash()));
         $this->assertNotNull($eraSummary->getStoredValue()->getEraInfo());
     }
+
+    public function testGetGlobalState(): void
+    {
+        $blockHashFromTheTestnet = '009516c04e6cb56d1d9b43070fd45cd80bf968739d39555282d8e66a8194e2e3';
+        $deployHashFromTheTestnet = 'deploy-39cf80560c87af0e69eb4a2c49f2404842244eafc63c497a6c8eb92f89b3c102';
+
+        $globalState = $this->rpcClient->getGlobalState($blockHashFromTheTestnet, $deployHashFromTheTestnet);
+        $this->assertEquals($deployHashFromTheTestnet, 'deploy-' . $globalState->getStoredValue()->getDeployInfo()->getDeployHash());
+    }
 }