WooCommerce REST API authentication: Use Oauth 1 and the WooCommerce REST API to retrieve order details. https://www.damiencarbery.com/2019/06/woocommerce-rest-api-authentication/

order-details.txt

{
    "id": 7755,
    "parent_id": 0,
    "number": "7755",
    "order_key": "wc_order_YjITxJBWgJIFu",
    "created_via": "programatically",
    "version": "3.6.4",
    "status": "completed",
    "currency": "EUR",
    "date_created": "2019-06-11T08:58:35",
    "date_created_gmt": "2019-06-11T08:58:35",
    "date_modified": "2019-06-11T08:58:36",
    "date_modified_gmt": "2019-06-11T08:58:36",
    "discount_total": "0.00",
    "discount_tax": "0.00",
    "shipping_total": "0.00",
    "shipping_tax": "0.00",
    "cart_tax": "0.00",
    "total": "42.00",
    "total_tax": "0.00",
    "prices_include_tax": false,
    "customer_id": 8,
    "customer_ip_address": "::1",
    "customer_user_agent": "PostmanRuntime/7.13.0",
    "customer_note": "",
    "billing": {
        "first_name": "John",
        "last_name": "Smith",
        "company": "",
        "address_1": "1234 Main Street",
        "address_2": "",
        "city": "Auckland",
        "state": "NA",
        "postcode": "3345",
        "country": "NZ",
        "email": "jsmith@example.com",
        "phone": ""
    },
    "shipping": {
        "first_name": "",
        "last_name": "",
        "company": "",
        "address_1": "",
        "address_2": "",
        "city": "",
        "state": "",
        "postcode": "",
        "country": ""
    },
    "payment_method": "bacs",
    "payment_method_title": "Direct bank transfer",
    "transaction_id": "",
    "date_paid": "2019-06-11T08:58:36",
    "date_paid_gmt": "2019-06-11T08:58:36",
    "date_completed": "2019-06-11T08:58:36",
    "date_completed_gmt": "2019-06-11T08:58:36",
    "cart_hash": "",
    "meta_data": [],
    "line_items": [
        {
            "id": 20,
            "name": "Hoodie",
            "product_id": 33,
            "variation_id": 0,
            "quantity": 1,
            "tax_class": "",
            "subtotal": "42.00",
            "subtotal_tax": "0.00",
            "total": "42.00",
            "total_tax": "0.00",
            "taxes": [],
            "meta_data": [],
            "sku": "",
            "price": 42
        }
    ],
    "tax_lines": [],
    "shipping_lines": [],
    "fee_lines": [],
    "coupon_lines": [],
    "refunds": [],
    "_links": {
        "self": [
            {
                "href": "http://localhost/storefront/wp-json/wc/v3/orders/7755"
            }
        ],
        "collection": [
            {
                "href": "http://localhost/storefront/wp-json/wc/v3/orders"
            }
        ],
        "customer": [
            {
                "href": "http://localhost/storefront/wp-json/wc/v3/customers/8"
            }
        ]
    }
}

show-single-order-rest-api.php

<?php

function join_params( $params ) {
	$query_params = array();

	foreach ( $params as $param_key => $param_value ) {
		$string = $param_key . '=' . $param_value;
		$query_params[] = str_replace( array( '+', '%7E' ), array( ' ', '~' ), rawurlencode( $string ) );
	}
	
	return implode( '%26', $query_params );
}


// WooCommerce REST API keys. Update these with your keys.
$consumer_key = 'ck_8d8b5e0ee1d65081f1270736db585dc62d3a3e88';
$consumer_secret = 'cs_c483bc1b79a0e81c15763cc990bdf8f2cb7f0020';

// Request URI.
$request_uri = 'http://localhost/storefront/wp-json/wc/v3/orders/7753';


// Unique once-off parameters.
$nonce = uniqid();
$timestamp = time();

$oauth_signature_method = 'HMAC-SHA1';

$hash_algorithm = strtolower( str_replace( 'HMAC-', '', $oauth_signature_method ) ); // sha1
$secret = $consumer_secret . '&';

$http_method = 'GET';
$base_request_uri = rawurlencode( $request_uri );
$params = array( 'oauth_consumer_key' => $consumer_key, 'oauth_nonce' => $nonce, 'oauth_signature_method' => 'HMAC-SHA1', 'oauth_timestamp' => $timestamp );
$query_string = join_params( $params );

$string_to_sign = $http_method . '&' . $base_request_uri . '&' . $query_string;
$oauth_signature = base64_encode( hash_hmac( $hash_algorithm, $string_to_sign, $secret, true ) );


$curl = curl_init();

curl_setopt_array($curl, array(
  CURLOPT_URL => $request_uri,
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => $http_method,
  CURLOPT_HTTPHEADER => array(
    "Accept: */*",
    "Authorization: OAuth oauth_consumer_key=\"".$consumer_key."\",oauth_signature_method=\"".$oauth_signature_method."\",oauth_timestamp=\"".$timestamp."\",oauth_nonce=\"".$nonce."\",oauth_signature=\"".$oauth_signature."\"",
    "Cache-Control: no-cache",
    "Connection: keep-alive",
    "Host: localhost",
    "User-Agent: PostmanRuntime/7.13.0",
    "accept-encoding: gzip, deflate",
    "cache-control: no-cache"
  ),
));

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}