Merge pull request #1 from byjg/4.0

Add feature to filter resulting anydataset
byjg · Oct 31, 2021 · 98843c7 · 98843c7
2 parents 6013985 + 2df4a83
commit 98843c7
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Showing 3 changed files with 268 additions and 24 deletions.
diff --git a/README.md b/README.md
@@ -17,7 +17,26 @@ See more about Anydataset [here](https://opensource.byjg.com/anydataset).
 
 ```php
 <?php
-$json = '[{"name":"Joao","surname":"Magalhaes","age":"38"},{"name":"John","surname":"Doe","age":"20"},{"name":"Jane","surname":"Smith","age":"18"}]';
+$json = <<<EOF
+[
+   {
+      "name":"Joao",
+      "surname":"Magalhaes",
+      "age":"38"
+   },
+   {
+      "name":"John",
+      "surname":"Doe",
+      "age":"20"
+   },
+   {
+      "name":"Jane",
+      "surname":"Smith",
+      "age":"18"
+   }
+]
+EOF;
+
 
 $dataset = new \ByJG\AnyDataset\Json\JsonDataset($json);
 
@@ -33,7 +52,23 @@ foreach ($iterator as $row) {
 
 ```php
 <?php
-$json = '{"menu": {"header": "SVG Viewer", "items": [ {"id": "Open"}, {"id": "OpenNew", "label": "Open New"} ]}}';
+$json = <<<EOF
+{
+   "menu":{
+      "header":"SVG Viewer",
+      "items":[
+         {
+            "id":"Open"
+         },
+         {
+            "id":"OpenNew",
+            "label":"Open New"
+         }
+      ]
+   }
+}
+EOF;
+
 
 $dataset = new \ByJG\AnyDataset\Json\JsonDataset($json);
 
@@ -44,6 +79,95 @@ foreach ($iterator as $row) {
 }
 ```
 
+### Extracting Fields
+
+```php
+$json = <<<EOF
+{
+   "menu":{
+      "header":"SVG Viewer",
+      "items":[
+         {
+            "id":"Open",
+            "metadata":{
+               "version":"1",
+               "date":"NA"
+            }
+         },
+         {
+            "id":"OpenNew",
+            "label":"Open New",
+            "metadata":{
+               "version":"2",
+               "date":"2021-10-01"
+            }
+         }
+      ]
+   }
+}
+EOF;
+
+
+$dataset = new \ByJG\AnyDataset\Json\JsonDataset($json);
+
+$iterator = $dataset->getIterator("/menu/items")
+                        ->withFields([
+                            "name" => "id",
+                            "version" => "metadata/version"
+                        ]);
+foreach ($iterator as $row) {
+    echo $row->get('name');       // Print "Open", "OpenNew"
+    echo $row->get('version');    // Print "1", "2"
+}
+```
+
+### Extract fields with wild mask
+
+```php
+$json = <<<EOF
+{
+   "menu":{
+      "header":"SVG Viewer",
+      "items":[
+         {
+            "id":"Open",
+            "metadata":[
+               {
+                  "version":"1",
+                  "date":"NA"
+               },
+               {
+                  "version":"beta",
+                  "date":"soon"
+               }
+            ]
+         },
+         {
+            "id":"OpenNew",
+            "label":"Open New",
+            "metadata":[
+               {
+                  "version":"2",
+                  "date":"2021-10-01"
+               }
+            ]
+         }
+      ]
+   }
+}
+EOF;
+
+$iterator = $dataset->getIterator("/menu/items")
+                        ->withFields([
+                            "name" => "id", 
+                            "version" => "metadata/*/version"
+                        ]);
+foreach ($iterator as $row) {
+    echo $row->get('name');       // Print "Open", "OpenNew"
+    echo $row->get('version');    // Print ["1", "Beta"], ["2"]
+}
+```
+
 ## Install
 
 Just type: `composer require "byjg/anydataset-json=4.0.*"`
@@ -56,3 +180,4 @@ vendor/bin/phpunit
 
 ----
 [Open source ByJG](http://opensource.byjg.com)
+k
diff --git a/src/JsonIterator.php b/src/JsonIterator.php
@@ -22,6 +22,8 @@ class JsonIterator extends GenericIterator
      */
     private $current = 0;
 
+    private $fieldDefinition = [];
+
     /**
      * JsonIterator constructor.
      *
@@ -36,31 +38,20 @@ public function __construct($jsonObject, $path = "", $throwErr = false)
             throw new InvalidArgumentException("Invalid JSON object");
         }
 
-        if ($path != "") {
-            if ($path[0] == "/") {
-                $path = substr($path, 1);
-            }
-
-            $pathAr = explode("/", $path);
-
-            $newjsonObject = $jsonObject;
+        $this->current = 0;
 
-            foreach ($pathAr as $key) {
-                if (array_key_exists($key, $newjsonObject)) {
-                    $newjsonObject = $newjsonObject[$key];
-                } elseif ($throwErr) {
-                    throw new IteratorException("Invalid path '$path' in JSON Object");
-                } else {
-                    $newjsonObject = array();
-                    break;
-                }
-            }
-            $this->jsonObject = $newjsonObject;
-        } else {
+        if (empty($path)) {
             $this->jsonObject = $jsonObject;
+            return;
         }
 
-        $this->current = 0;
+        $this->jsonObject = $this->parseField($jsonObject, explode("/", ltrim("$path/*", "/")));
+        if (is_null($this->jsonObject)) {
+            if ($throwErr) {
+                throw new IteratorException("Invalid path '$path' in JSON Object");
+            }
+            $this->jsonObject = [];
+        }
     }
 
     public function count()
@@ -93,11 +84,51 @@ public function moveNext()
             throw new IteratorException("No more records. Did you used hasNext() before moveNext()?");
         }
 
-        return new Row($this->jsonObject[$this->current++]);
+        return new Row($this->parseFields($this->jsonObject[$this->current++]));
+    }
+
+    private function parseFields($jsonObject) {
+        if (empty($this->fieldDefinition)) {
+            return $jsonObject;
+        }
+
+        $valueList = [];
+        foreach ($this->fieldDefinition as $field => $path) {
+            $pathList = explode("/", ltrim($path, "/"));
+            $valueList[$field] = $this->parseField($jsonObject, $pathList);
+        }
+
+        return $valueList;
+    }
+
+    private function parseField($record, $pathList)
+    {
+        $value = $record;
+        while($pathElement = array_shift($pathList)) {
+            if ($pathElement == "*") {
+                $result = [];
+                foreach ($value as $item) {
+                    $result[] = $this->parseField($item, $pathList);
+                }
+                $value = $result;
+                break;
+            }
+            if (!isset($value[$pathElement])) {
+                $value = null;
+                break;
+            }
+            $value = $value[$pathElement];
+        }
+        return $value;
     }
 
     public function key()
     {
         return $this->current;
     }
+
+    public function withFields($definition) {
+        $this->fieldDefinition = $definition;
+        return $this;
+    }
 }
diff --git a/tests/JsonDatasetWithFieldsTest.php b/tests/JsonDatasetWithFieldsTest.php
@@ -0,0 +1,88 @@
+<?php
+
+namespace Tests\AnyDataset\Json;
+
+use ByJG\AnyDataset\Core\IteratorInterface;
+use ByJG\AnyDataset\Json\JsonDataset;
+use ByJG\AnyDataset\Core\Row;
+use PHPUnit\Framework\TestCase;
+
+class JsonDatasetWithFieldsTest extends TestCase
+{
+
+    const JSON_OK = '{"menu": {"header": "SVG Viewer", "items": [ {"id": "Open", "metadata": {"version": "1", "date": "NA"} }, {"id": "OpenNew", "label": "Open New", "metadata": {"version": "2", "date": "2021-10-01"}} ]}}';
+
+    protected $iterator;
+    protected $arrTest = array();
+
+    // Run before each test case
+    public function setUp()
+    {
+        $this->arrTest = array();
+        $this->arrTest[] = array("name" => "Open", "version" => "1");
+        $this->arrTest[] = array("name" => "OpenNew", "version" => "2");
+
+        $jsonDataset = new JsonDataset(JsonDatasetWithFieldsTest::JSON_OK);
+        $this->iterator = $jsonDataset->getIterator("/menu/items")->withFields(["name" => "id", "version" => "metadata/version"]);
+    }
+
+    // Run end each test case
+    public function teardown()
+    {
+        $this->iterator = null;
+    }
+
+    public function testcreateJsonIterator()
+    {
+        $this->assertTrue($this->iterator instanceof IteratorInterface); //, "Resultant object must be an interator");
+        $this->assertTrue($this->iterator->hasNext()); // "hasNext() method must be true");
+        $this->assertEquals(2, $this->iterator->Count()); //, "Count() method must return 2");
+    }
+
+    public function testnavigateJsonIterator()
+    {
+        $count = 0;
+        while ($this->iterator->hasNext()) {
+            $this->assertSingleRow($this->iterator->moveNext(), $count++);
+        }
+
+        $this->assertEquals(2, $this->iterator->count(), 2); //, "Count() method must return 2");
+    }
+
+    public function testnavigateJsonIterator2()
+    {
+        $this->assertEquals($this->arrTest, $this->iterator->toArray());
+    }
+
+    public function testArrayFieldDefinition()
+    {
+        $jsonDataset = new JsonDataset('{"menu": {"header": "SVG Viewer", "items": [ {"id": "Open", "metadata": [{"version": "1", "date": "NA"}, {"version": "beta", "date": "soon"}] }, {"id": "OpenNew", "label": "Open New", "metadata": [{"version": "2", "date": "2021-10-01"}] } ]}}');
+
+        $iterator = $jsonDataset->getIterator("/menu/items")->withFields(["name" => "id", "version" => "metadata/*/version"]);
+
+        $this->assertEquals([
+            ["name" => "Open", "version" => ["1", "beta"]],
+            ["name" => "OpenNew", "version" => ["2"]]
+        ], $iterator->toArray());
+    }
+
+    public function testNonExistentFieldDefinition()
+    {
+        $jsonDataset = new JsonDataset(JsonDatasetWithFieldsTest::JSON_OK);
+        $iterator = $jsonDataset->getIterator("/menu/items")->withFields(["name" => "none", "version" => "metadata/version/nonexistantfield"]);
+
+        $this->assertEquals([
+            ["name" => null, "version" => null],
+            ["name" => null, "version" => null]
+        ], $iterator->toArray());
+    }
+
+    /**
+     * @param Row $sr
+     */
+    public function assertSingleRow($sr, $count)
+    {
+        $this->assertEquals($sr->get("name"), $this->arrTest[$count]["name"]);
+        $this->assertEquals($sr->get("version"), $this->arrTest[$count]["version"]);
+    }
+}