Magento 2 REST API Get TaxRate by Tax Class ID

Question

i'm using RestSharp in C# to connect with Magento2 REST API.

Everythings fine, except one simple thing:

lets say i've got a product, in its JSON-DATA there is a tax_class_id "4". Inside of this tax_class_id theres a tax rate of 19% integrated. How do i get the taxrate "19" from the tax_class_id "4"?

here's the call:

var response = new RestRequest("/rest/default/V1/products/SampleProduct",Method.GET);
response.RequestFormat = DataFormat.JSON;
response.AddHeader("Authorization","Bearer " + Token);
response.AddHeader("Accept","application/json");

here's the json-data from the response (all unnessary data like meta data etc. are cropped). I added some annotation "<<" for better understanding what i need

{
  "items": [
    {
      "id": 1,
      "sku": "SampleProduct",
      "name": "a Simple Sample Product",
      "attribute_set_id": 4,
      "price": 4.99,            << this is with tax, i need the taxrate to get the price without tax aswell 
      "status": 1,
      "visibility": 4,
      "type_id": "simple",
      "created_at": "2017-10-04 12:11:03",
      "updated_at": "2017-10-24 10:02:50",
      "product_links": [

      ],
      "tier_prices": [

      ],
      "custom_attributes": [
        {
          "attribute_code": "tax_class_id",
          "value": "4"      << i've got the class_id, now i must have the taxrate. Its 19% but how do i get the value "19"
        }
      ]
    }
  ],
  "total_count": 1
}

what can't be done:

- using PHP to do the Task
- changing some files to get it to work

what i have:

- the Magento 2.2 REST API
- C# as programming language to work with
- a Magento Shop with Access Token for REST API Requests, but no other physical access
- the product and all its data (except the taxrate ^^)
- the tax_class_id of the product
- the information that tax_class_id in *this* Shop for *this* product , id = 4 is 19% taxrate
- it must work with every other shop, every other tax_class_id, every other product as well, where e.g. id = 1 is 19% and id = 4 is like 7%

what i can use to get to it:

- the {TAXCLASSID} which is not the same as the {TAXRATEID}

what i need:

- the {TAXRATEID} to get the rate (e.g. 19 or 8.25)

Hope someone can help me with that task. Thanks in advantage.

Answer 1

Looking at the swagger documentation could you not use

taxTaxRateRepositoryV1

Do a GET to this -

rest/V1/taxRates/{TAXRATEID}

to get an example response like -

{
     "id": 1,
     "tax_country_id": "US",
     "tax_region_id": 12,
     "region_name": "CA",
     "tax_postcode": "*",
     "rate": 8.25,
     "code": "US-CA-*-Rate 1",
     "titles": []
}

Rate I assume is the value you would need from this.

Answer 2

After hours of wobbling around the Swagger documentation i figured it out myself:

There is no {TAXCLASSID} to {TAXRATEID} Function. You must iterate over the taxRule Repository with the following searchCriteria

field = id
value = 0
condition_type = gt

after this there is a node called "product_tax_class_ids". The Array-Index corresponds to the Array-Index in the next node "tax_rate_ids".

After that you'll have the tax_rate_id that fits to your products tax_class_id. With this you can use the Answer from BigDaddyL, edited by Manoj in this Question to get the rate by opening

rest/V1/taxRates/{yourTaxRateID}

and read the value in field "rate"

Thanks for you Help ;)