How to parse and extract key value pairs from the Textract response in PHP in JSON format

Thanks for reaching out regarding tables. Amazon Textract can extract tables and cells inside the tables. Please refer to the documentation here to know more about the table block type and cell block types and their relationships.

Following is sample code for extract table block type:

$blocksMap = array();
   $tableBlocks = array();
   foreach ($result["Blocks"] as $block) {
      $blocksMap[$block["Id"]] = $block;
      if ($block["BlockType"]=="TABLE") {
         array_push($tableBlocks, $block);
      }
   }

Using the blocksMap and tableBlocks cell blocks can be extracted:

foreach ($tableBlocks as $table) {
      foreach($table["Relationships"] as $relationship) {
         if ($relationship["Type"]=="CHILD") {
            $rowsMap=array();
            foreach($relationship["Ids"] as $childId) {
               $cell = $blocksMap[$childId];
               if (!is_null($cell) && isset($cell["BlockType"]) && $cell["BlockType"]=="CELL") {
                  $rowIndex = $cell["RowIndex"];
                  $colIndex = $cell["ColumnIndex"];
                  if (!isset($rowsMap[$rowIndex])) {
                     $rowsMap[$rowIndex] = array();
                  }
                  $rowsMap[$rowIndex][$colIndex] = $cell;
               }
            }
            print_r($rowsMap);
         }
      }
   }

Similar idea can be applied to get to words and extract the text of the cell. Please refer to sample code in python (see here) regarding the same.

Thank you for using Amazon Textract.

The response can be extracted using code like:

print($result["DocumentMetadata"]["Pages"]);

foreach ($result["Blocks"] as $value) {
      if ($value["BlockType"]=='KEY_VALUE_SET') {
         print_r($value);
      }
}

The response structure for AnalyzeExpense (refer here) is different from the response structure of AnalyzeDocument (refer here).

In order to extract the key value pairs in AnalyzeDocument response please refer to logic presented in the sample python code (see here). You can take reference from there in order to code the extraction for key value pairs.

Hi,

As per your help and direction i followed the python code example(as per the linked share) But I'm not getting the expected result as per the below file uploaded: http://drnko.rs-technology.co.in/aws/receipt16.jpg

What am i missing??

Below is the code in PHP:

$result = $client->analyzeDocument($options);

$blocksMap = array();
   $tableBlocks = array();
   
   foreach ($result["Blocks"] as $block) {
      $blocksMap[$block["Id"]] = $block;
      if ($block["BlockType"]=="TABLE") {
         array_push($tableBlocks, $block);
      }
   }
   
foreach ($tableBlocks as $table) {
      foreach($table["Relationships"] as $relationship) {
         if ($relationship["Type"]=="CHILD") {
            $rowsMap=array();
            foreach($relationship["Ids"] as $childId) {
               $cell = $blocksMap[$childId];
               if (!is_null($cell) && isset($cell["BlockType"]) && $cell["BlockType"]=="CELL") {
                  $rowIndex = $cell["RowIndex"];
                  $colIndex = $cell["ColumnIndex"];
                  if (!isset($rowsMap[$rowIndex])) {
                     $rowsMap[$rowIndex] = array();
                  }
                  $rowsMap[$rowIndex][$colIndex] = getText($cell, $blocks_map);
                  
               }
            }
            print_r(json_encode($rowsMap));
         }
      }
   }
   
   function getText($cells, $blocks_map){
       $text = '';
        if (isset($cells["Relationships"])) {
            foreach($cells["Relationships"] as $relationship){
                
                if($relationship["Type"] == "CHILD") {
                    foreach($relationship["Ids"] as $child_id){    
                        $word = $blocks_map[$child_id];
                    if($word["BlockType"] == "WORD"){
                        $text += $word["Text"] + ' ';
                        print_r($text . '\n');
                    }
                    if($word["BlockType"] == "SELECTION_ELEMENT"){
                        if($word["SelectionStatus"] =="SELECTED"){
                            $text +=  'X ';
                        }
                    }
                    }
                }
            }
    return $text;
      
   }

}

Result output:

{"1":{"1":null,"2":null},"2":{"1":null,"2":null},"3":{"1":null,"2":null}}{"1":{"1":null,"2":null},"2":{"1":null,"2":null},"3":{"1":null,"2":null}}{"1":{"1":null,"2":null,"3":null},"2":{"1":null,"2":null,"3":null},"3":{"1":null,"2":null,"3":null}}{"1":{"1":null,"2":null,"3":null},"2":{"1":null,"2":null,"3":null},"3":{"1":null,"2":null,"3":null}}

<?php
#Here is the code for textract key and value pair using php
function ParserFile($filename)
{
    $Val = get_kv_map($filename);
    $key_map = $Val["key_map"];
    $value_map = $Val["value_map"];
    $block_map = $Val["block_map"];
    $kvs = get_kv_relationship($key_map, $value_map, $block_map);
    print_r($kvs);
    die();
}

function get_kv_relationship($key_map, $value_map, $block_map)
{
    foreach ($key_map as $block_id => $key_block) {
        $value_block = find_value_block($key_block, $value_map);
        $key = get_text($key_block, $block_map);
        $val = get_text($value_block, $block_map);
        $kvs[$key] = $val;
    }
    return $kvs;
}

function find_value_block($key_block, $value_map)
{
    foreach ($key_block["Relationships"] as $relationship) {
        if ($relationship["Type"] == "VALUE") {
            foreach ($relationship["Ids"] as $value_id) {
                $value_block = $value_map[$value_id];
                return $value_block;
            }
        }
    }
}
function get_text($result, $blocks_map)
{
    $text = "";
    if (array_key_exists("Relationships", $result)) {
        foreach ($result["Relationships"] as $relationship) {
            if ($relationship["Type"] == "CHILD") {
                foreach ($relationship["Ids"] as $child_id) {
                    $word = $blocks_map[$child_id];
                    if ($word["BlockType"] == "WORD") {
                        $text = $word["Text"];
                    }
                    if ($word["BlockType"] == "SELECTION_ELEMENT") {
                        if ($word["SelectionStatus"] == "SELECTED") {
                            $text = "X ";
                        }
                    }
                }
            }
        }
    }

    return $text;
}
function get_kv_map($filename)
{
    $client = new TextractClient([
        "region" => $ClientRegion,
        "version" => $ClientVersion,
        "credentials" => [
            "key" => $Accesskey,
            "secret" => $EncryptedKey,
        ],
    ]);
    $file = fopen($filename, "rb");
    $contents = fread($file, filesize($filename));
    fclose($file);
    fclose($file);
    $options = [
        "Document" => [
            "Bytes" => $contents,
        ],
        "FeatureTypes" => ["FORMS", "TABLES"], // REQUIRED
    ];
    $result = $client->analyzeDocument($options);

    $blocks = $result["Blocks"];

    $key_map = [];
    $value_map = [];
    $block_map = [];
    foreach ($blocks as $block) {
        $block_id = $block["Id"];
        $block_map[$block_id] = $block;
        if ($block["BlockType"] == "KEY_VALUE_SET") {
            if (in_array("KEY", $block["EntityTypes"])) {
                $key_map[$block_id] = $block;
            } else {
                $value_map[$block_id] = $block;
            }
        }
    }

    return [
        "key_map" => $key_map,
        "value_map" => $value_map,
        "block_map" => $block_map,
    ];
}

$filename = "imagedir.png";
ParserFile($filename);