Append Custom Shipping method to list of methods

Question

In Magento 2.3 I want to append a shipping method to my collection of methods but it's not working. This is what I'm doing:

1. I'm selecting the cheapest rate from the collection of rates with $cheapestRate = $this->getResult()->getCheapestRate().
2. Then, I reset the original collection with $this->getResult()->reset()

3. I append the cheapest rate to the now clean collection of methods with $method->setCarrier($cheapestRate['carrier']); $method->setCarrierTitle($cheapestRate['carrier_title']); $method->setMethod($cheapestRate['method']); $method->setMethodTitle($cheapestRate['method_title']); $method->setCost($cheapestRate['cost']); $method->setPrice($cheapestRate['price']); $result->append($method); $this->getResult()->append($result);

4. I'm displaying the cheapest rate so far. Now, I want to add a custom method with a cost of $0.00. This is what I do: private function addCustomShippingToMethods($method, $result) { $method->setCarrier('custom_shipping'); $method->setCarrierTitle('custom_shipping'); $method->setMethod('custom_shipping'); $method->setMethodTitle('custom_shipping'); $method->setPrice(0); $method->setCost(0); $result->append($method); return $this; }

5. So, to insert the custom method in step 4, I call addCustomShippingToMethods right after the last line in step 3 like this $this->addCustomShippingToMethods($method, $result);

The problem is that I only see the custom method in the checkout page but not the cheapest one. If I remove the call to add the custom method then I only see the cheapest one.

In a few words, all the shipping options I want to see in the checkout page are the cheapest rate and the custom shipping at $0.00.

What am I doing wrong?

Thanks for any advice.

Answer 1

So, in order to make it work I had to change step 4. It goes like this:

private function addCustomShippingToMethods() {
    $method = $this->_rateMethodFactory->create();
    $result = $this->_rateResultFactory->create();

    $method->setCarrier('custom_shipping');
    $method->setCarrierTitle('custom_shipping');
    $method->setMethod('custom_shipping');
    $method->setMethodTitle('custom_shipping');
    $method->setPrice(0);
    $method->setCost(0);
    $result->append($method);

    return $result;
}

Then I change step 5 with this:

$this->addCustomShippingToMethods();

Silly me. I thought I didn't need to create a $method and a $result for the custom shipping method since they were already there. I also had to return $result, not $this.

I hope this helps somebody.