added Invoice creation, void, list, resolve functions

README.md

@@ -13,6 +13,7 @@ The official PHP library for the [Coinbase Commerce API](https://commerce.coinba
    * [Usage](#usage)
       * [Checkouts](#checkouts)
       * [Charges](#charges)
+      * [Invoices](#invoices)
       * [Events](#events)
       * [Webhooks](#webhooks)
       * [Warnings](#warnings)
@@ -264,6 +265,82 @@ if ($chargeObj) {
 }
 ```
 
+## Invoices
+[Invoices API docs](https://commerce.coinbase.com/docs/api/#invoices)
+More examples on how to use charges can be found in the [`examples/Resources/InvoiceExample.php`](examples/Resources/InvoiceExample.php) file
+
+### Load invoice resource class
+``` php
+use CoinbaseCommerce\Resources\Invoice;
+```
+### Retrieve
+``` php
+$invoiceObj = Invoice::retrieve(<invoice_id>);
+```
+### Create
+``` php
+$invoiceData = [
+    'business_name' => 'Crypto Account LLC',
+    'customer_email' => 'customer@test.com',
+    'customer_name' => 'Test Customer',
+    'local_price' => [
+        'amount' => '100.00',
+        'currency' => 'USD'
+    ],
+    'memo' => 'Taxes and Accounting Services'
+];
+Invoice::create($invoiceData);
+
+// or
+$invoiceObj = new Invoice();
+
+$invoiceObj->business_name = 'Crypto Account LLC';
+$invoiceObj->customer_email = 'customer@test.com';
+$invoiceObj->customer_name = 'Test Customer';
+$invoiceObj->local_price = [
+    'amount' => '100.00',
+    'currency' => 'USD'
+];
+$invoiceObj->memo = 'Taxes and Accounting Services';
+$invoiceObj->save();
+```
+### List
+``` php
+$list = Invoice::getList();
+
+foreach($list as $invoice) {
+    var_dump($list);
+}
+
+$pagination = $list->getPagination();
+```
+### Get all invoices
+``` php
+$allInvoices = Invoice::getAll();
+```
+
+### Resolve an invoice
+Resolve an invoice that has been previously marked as unresolved. 
+```
+$invoiceObj = Invoice::retrieve(<charge_id>);
+
+if ($invoiceObj) {
+    $invoiceObj->resolve();
+}
+```
+
+### Void an invoice
+Voids an invoice that has been previously created. 
+Note: Only new or viewed invoices can be successfully voided. Once payment is detected, invoice can no longer be canceled.
+
+```
+$invoiceObj = Invoice::retrieve(<invoice_id>);
+
+if ($invoiceObj) {
+    $invoiceObj->void();
+}
+```
+
 ## Events
 [Events API Docs](https://commerce.coinbase.com/docs/api/#events)
 More examples on how to use events can be found in the [`examples/Resources/EventExample.php`](examples/Resources/EventExample.php) file

examples/Resources/InvoiceExample.php

@@ -0,0 +1,87 @@
+<?php
+require_once __DIR__ . "/vendor/autoload.php";
+
+use CoinbaseCommerce\ApiClient;
+use CoinbaseCommerce\Resources\Invoice;
+
+/**
+ * Init ApiClient with your Api Key
+ * Your Api Keys are available in the Coinbase Commerce Dashboard.
+ * Make sure you don't store your API Key in your source code!
+ */
+ApiClient::init("API_KEY");
+
+$invoiceObj = new Invoice(
+	[
+	    'business_name' => 'Crypto Account LLC',
+	    'customer_email' => 'customer@test.com',
+	    'customer_name' => 'Test Customer',
+	    'local_price' => [
+	        'amount' => '100.00',
+	        'currency' => 'USD'
+	    ],
+	    'memo' => 'Taxes and Accounting Services'
+	];
+);
+
+try {
+    $invoiceObj->save();
+    echo sprintf("Successfully created new invoice with id: %s \n", $invoiceObj->id);
+} catch (\Exception $exception) {
+    echo sprintf("Enable to create invoice. Error: %s \n", $exception->getMessage());
+}
+
+if ($invoiceObj->id) {
+    // Retrieve invoice by "id"
+    try {
+        $retrievedInvoice = Invoice::retrieve($invoiceObj->id);
+        echo sprintf("Successfully retrieved invoice\n");
+        echo $retrievedInvoice;
+    } catch (\Exception $exception) {
+        echo sprintf("Enable to retrieve invoice. Error: %s \n", $exception->getMessage());
+    }
+}
+
+try {
+    $list = Invoice::getList(["limit" => 5]);
+    echo sprintf("Successfully got list of invoices\n");
+
+    if (count($list)) {
+        echo sprintf("Invoices in list:\n");
+
+        foreach ($list as $invoice) {
+            echo $invoice;
+        }
+    }
+
+    echo sprintf("List's pagination:\n");
+    print_r($list->getPagination());
+
+    echo sprintf("Number of all invoices - %s \n", $list->countAll());
+} catch (\Exception $exception) {
+    echo sprintf("Enable to get list of invoices. Error: %s \n", $exception->getMessage());
+}
+
+if (isset($list) && $list->hasNext()) {
+    // Load next page with previous settings (limit=5)
+    try {
+        $list->loadNext();
+        echo sprintf("Next page of invoices: \n");
+        foreach ($list as $invoice) {
+            echo $invoice;
+        }
+    } catch (\Exception $exception) {
+        echo sprintf("Enable to get new page of invoices. Error: %s \n", $exception->getMessage());
+    }
+}
+
+// Load all available invoices
+try {
+    $allInvoice = Invoice::getAll();
+    echo sprintf("Successfully got all invoices:\n");
+    foreach ($allInvoice as $invoice) {
+        echo $invoice;
+    }
+} catch (\Exception $exception) {
+    echo sprintf("Enable to get all invoices. Error: %s \n", $exception->getMessage());
+}

src/Resources/Invoice.php

@@ -0,0 +1,38 @@
+<?php
+namespace CoinbaseCommerce\Resources;
+
+use CoinbaseCommerce\Resources\Operations\CreateMethodTrait;
+use CoinbaseCommerce\Resources\Operations\ReadMethodTrait;
+use CoinbaseCommerce\Resources\Operations\SaveMethodTrait;
+use CoinbaseCommerce\Util;
+
+class Invoice extends ApiResource implements ResourcePathInterface
+{
+    use ReadMethodTrait, CreateMethodTrait, SaveMethodTrait;
+
+    /**
+     * @return string
+     */
+    public static function getResourcePath()
+    {
+        return 'invoices';
+    }
+
+    public function void($headers = [])
+    {
+        $id = $this->id;
+        $path = Util::joinPath(static::getResourcePath(), $id, 'void');
+        $client = static::getClient();
+        $response = $client->put($path, [], $headers);
+        $this->refreshFrom($response);
+    }
+
+    public function resolve($headers = [])
+    {
+        $id = $this->id;
+        $path = Util::joinPath(static::getResourcePath(), $id, 'resolve');
+        $client = static::getClient();
+        $response = $client->post($path, [], $headers);
+        $this->refreshFrom($response);
+    }
+}