Return custom HTTP responses#

Define returned HTTP status codes#

Using the DkuCustomApiException class, you can control which HTTP status code and message are returned by a deployed API endpoint. This is helpful when you want to handle unexpected response states.

The DkuCustomApiException exception’s constructor has two parameters:

message - mandatory
http_status_code - optional with the default value of 500

Python function#

def api_py_function(p1, p2, p3):
    http_headers = dku_http_request_metadata.headers

    # Your custom logic for handling specific header values
    if not http_headers.get("Authorization"):
        raise DkuCustomApiException("The caller is not authorized", http_status_code=401)

    # Python function logic
    result = ...

    return result

Custom prediction (classification)#

The DkuCustomApiException class is only accessible from the predict method

from  dataiku.apinode.predict.predictor import ClassificationPredictor
import pandas as pd
    def predict(self, features_df):
        http_headers = dku_http_request_metadata.headers

        # Your custom logic for handling specific header values
        if not http_headers.get("Authorization"):
            raise DkuCustomApiException("The caller is not authorized", http_status_code=401)

        # Prediction logic
        ...

Custom prediction (regression)#

The DkuCustomApiException class is only accessible from the predict method

from  dataiku.apinode.predict.predictor import RegressionPredictor
import pandas as pd
class MyPredictor(RegressionPredictor):
    def predict(self, features_df):
        http_headers = dku_http_request_metadata.headers

        # Your custom logic for handling specific header values
        if not http_headers.get("Authorization"):
            raise DkuCustomApiException("The caller is not authorized", http_status_code=401)

        # Prediction logic
        ...

Customize HTTP response content#

Warning: this feature is only available for Python function endpoints.

The DkuCustomHttpResponse can help define the response content type and HTTP headers returned by a deployed Python function API endpoint.

The feature is disabled by default and can be enabled in Python function endpoint settings by checking the “Returns custom response” option. Only the Static Dataiku API node and Kubernetes cluster infrastructure types support this feature.

Text response#

from dataiku.apinode import DkuCustomHttpResponse

def api_py_function():
    response = DkuCustomHttpResponse.create_text_response("Hello, World!")
    return response

XML response#

import xml.etree.ElementTree as ET
from dataiku.apinode import DkuCustomHttpResponse

def api_py_function():
    root = ET.Element("person")
    name = ET.SubElement(root, "name")
    name.text = "John Doe"
    age = ET.SubElement(root, "age")
    age.text = str(42)
    xml_string = ET.tostring(root, encoding="unicode")
    response = DkuCustomHttpResponse.create_text_response(xml_string, content_type="text/xml")
    return response

JSON response#

from dataiku.apinode import DkuCustomHttpResponse

def api_py_function():
    my_values = dict()
    my_values["a"] = "b"
    my_values["c"] = ["e", 42]
    return DkuCustomHttpResponse.create_json_response(my_values, content_type="application/json")

Image response#

You can use a content type that reflects the type of the image: image/png, image/jpg, etc. All common MIME types can be found here.

import base64
from dataiku.apinode import DkuCustomHttpResponse

def api_py_function():
    obj = base64.b64decode("<your-image-encoded-with-base64>")
    response = DkuCustomHttpResponse.create_binary_response(obj, content_type="image/png")
    return response

Extra headers#

from dataiku.apinode import DkuCustomHttpResponse

def api_py_function():
    response = DkuCustomHttpResponse.create_text_response("Hello, World!")
    # Add headers after instantiation
    response.headers["Machin"] = "Truc"
    # Using the add_header method, define multiple headers with the same key. Valid in a limited set of cases, such as Set-Cookie
    response.add_header("Set-Cookie", "chocolate")
    response.add_header("Set-Cookie", "pecan")
    return response

Using the direct initialization of `DkuCustomHttpResponse`#

from dataiku.apinode import DkuCustomHttpResponse

def api_py_function():
    response = DkuCustomHttpResponse(
        200,
        "Hello No Helper World", {
        "Content-Type": "text/plain",
        "Content-Encoding": "utf-8"
        }
    )
    return response