Tracking API implemented

Author: rgodiyal

src/Tracking.php

@@ -0,0 +1,73 @@
+<?php
+
+namespace RahulGodiyal\PhpUpsApiWrapper;
+
+use RahulGodiyal\PhpUpsApiWrapper\Auth;
+use RahulGodiyal\PhpUpsApiWrapper\Utils\HttpClient;
+
+class Tracking extends Auth
+{
+    private const QUERY = [
+        "locale" => "en_US",
+        "returnSignature" => "false",
+        "returnMilestones" => "false",
+        "returnPOD" => "false"
+    ];
+    private static ?string $trackingNumber;
+
+    public static function setTrackingNumber(string $trackingNumber): self
+    {
+        self::$trackingNumber = $trackingNumber;
+        return new self;
+    }
+
+    public function fetch(string $client_id, string $client_secret): array
+    {
+        $auth = $this->authenticate($client_id, $client_secret);
+
+        if ($auth['status'] == 'fail') {
+            return $auth;
+        }
+
+        $access_token = $auth['access_token'];
+
+        $httpClient = new HttpClient();
+        $httpClient->setHeader([
+            "Authorization: Bearer $access_token",
+            "transId: string",
+            "transactionSrc: testing"
+        ]);
+        $httpClient->setUrl($this->_getAPIBaseURL() . "/api/track/v1/details/" . self::$trackingNumber . "?" . http_build_query(self::QUERY));
+        $httpClient->setMethod("GET");
+        $res = $httpClient->fetch();
+
+        if (!isset($res->trackResponse)) {
+            if (isset($res->response)) {
+                $error = $res->response->errors[0]->message;
+            } else {
+                $error = "Fetching tracking details failed! Please try again.";
+            }
+            return ['status' => 'fail', 'msg' => $error];
+        }
+
+        if (!isset($res->trackResponse->shipment)) {
+            return ['status' => 'fail', 'msg' => "Invalid Tracking Number."];
+        }
+
+        if (isset($res->trackResponse->shipment[0]->warnings)) {
+            $error_arr = $res->trackResponse->shipment[0]->warnings;
+            if (isset($error_arr[0]->message)) {
+                return ['status' => 'fail', 'msg' => $error_arr[0]->message];
+            }
+        }
+
+        $trackingDetails = $res->trackResponse->shipment;
+        return ['status' => 'success', 'data' => $trackingDetails];
+    }
+    
+    public function setMode(string $mode): self
+    {
+        parent::setMode($mode);
+        return $this;
+    }
+}