matlab.rest_function_service.client.MWHttpClient Class

R2026b

Python client interface for calling MATLAB REST function service

Since R2026b

Description

The Python^® class matlab.rest_function_service.client.MWHttpClient creates an object for calling MATLAB^® functions in a REST function service. Use this object in your Python client applications to pass inputs to MATLAB functions using native Python data types. Data is passed synchronously using the HTTPS request-response model.

Creation

Before creating a matlab.rest_function_service.client.MWHttpClient object, follow these steps to make the class accessible from your Python application:

1. Install the Python Client for MATLAB REST Function Service package from the Python Package Index (PyPI). At the operating system command line, run this command.

   python -m pip install matlab-restfcnservice-client

2. In your Python application, import the matlab package and MWHttpClient class from Python Client for REST Function Service.

   import matlab
   from matlab.rest_function_service.client import MWHttpClient

Then create an object of the matlab.rest_function_service.client.MWHttpClient class using one of the syntaxes shown below.

Description

client = MWHttpClient(base_url=url,rest_personal_access_token=token,certificate=cert) creates an object for calling the MATLAB REST function service at the specified URL. The service authenticates the client using the specified access token and certificate file.

client = MWHttpClient(___,timeout_sec=timeout) also specifies how many seconds the Python application waits for a response from the MATLAB REST function service before timing out. Specify the timeout value after all the input arguments from the previous syntax.

Input Arguments

url — HTTPS request URL

Python string scalar

HTTPS request URL used to call the MATLAB REST function service, specified as a Python string scalar. Obtain this URL from the RequestUrl property of the ClientRequestInfo object that MATLAB returns when you start the service. For more details, see Create MATLAB REST Function Services.

Do not include the service name in url. For example, if the RequestUrl property is "https://localhost:9920/feval/v1/myService", then specify url as "https://localhost:9920/feval/v1".

Trailing slashes in url are ignored.

Example: "https://localhost:9920/feval/v1"

Example: "https://localhost:9920/feval/v1/"

Data Types: str

token — Personal access token

Python string scalar

Personal access token required to call the MATLAB REST function service, specified as a Python string scalar. Obtain this token from the RESTPersonalAccessToken property of the ClientRequestInfo object that MATLAB returns when you start the service. For more details, see Create MATLAB REST Function Services.

Example: "AQIDBAUGBwgJCgsMDQ4PEBESExQVFhcYGRobHB0eHyA="

Data Types: str

cert — Certificate file

Python string scalar

Certificate file required to call the MATLAB REST function service, specified as a Python string scalar representing the full path to a PEM file. Obtain this file path from the CertificateLocation property of the ClientRequestInfo object that MATLAB returns when you start the service. For more details, see Create MATLAB REST Function Services.

To prevent Python from interpreting Windows^® backslashes as escape characters, format cert as a raw string.

Example: r"C:\Users\username\AppData\Roaming\MathWorks\restfcnconnector\publickey.pem"

Data Types: str

timeout — Timeout value (s)

120 (2 minutes) (default) | positive Python integer

Timeout value, in seconds, specified as a positive Python integer. If the client application does not receive a response from the MATLAB REST function service after this number of seconds, the request times out with an error.

Example: 15

Data Types: int

Methods

Specialized Operators and Functions

The MWHttpClient interface object, client, provides a method for calling MATLAB functions running on the REST service.

Syntax

response = client.serviceName.functionName(*args, **kwargs)

Description

response = client.serviceName.functionName(*args, **kwargs) calls MATLAB function functionName running on MATLAB REST function service serviceName and returns the function response data. The response data is returned as native Python data types.

Input Arguments

• *args — Positional input arguments used to call the MATLAB function, specified as any Python data type listed in Data Type Conversions Between MATLAB REST Function Services and Python.

• **kwargs — Optional keyword arguments used to call the MATLAB function, which include:

  • nargout — Number of output arguments that the client application expects the MATLAB function to return, specified as a nonnegative integer. The default is 1.

  • Pass all other keyword arguments as name-value arguments to the MATLAB function. Specify them as any Python data type listed in Data Type Conversions Between MATLAB REST Function Services and Python.

Examples

From MATLAB REST function service myService, call MATLAB function myFunc with input X.

out = client.myService.myFunc(X)

Pass a name-value argument to the function.

out = client.myService.myFunc(X,myName=myValue)

Return two outputs from the function.

out1, out2 = client.myService.myFunc(X,myName=myValue,nargout=2)

For more examples, see Call MATLAB Functions from Python Using REST.

Examples

Create Python REST Client

In your Python application file, create a Python REST client for calling a MATLAB REST function service.

import matlab
from matlab.rest_function_service.client import MWHttpClient

url = "https://localhost:9920/matlab/feval/v1"
token = "AQIDBAUGBwgJCgsMDQ4PEBESExQVFhcYGRobHB0eHyA="
cert = r"C:\Users\user\AppData\Roaming\MathWorks\restfcnconnector\publickey.pem"

client = MWHttpClient(
            base_url=url,
            rest_personal_access_token=token,
            certificate=cert)

For an example of how to call MATLAB functions using this client, see Call MATLAB Functions from Python Using REST.

Set Timeout Value in Python REST Client

In your Python application file, create a Python REST client that times out if it does not receive a response from the MATLAB REST function service after one minute.

import matlab
from matlab.rest_function_service.client import MWHttpClient

url = "https://localhost:9920/matlab/feval/v1"
token = "AQIDBAUGBwgJCgsMDQ4PEBESExQVFhcYGRobHB0eHyA="
cert = r"C:\Users\user\AppData\Roaming\MathWorks\restfcnconnector\publickey.pem"
timeout = 60

client = MWHttpClient(
            base_url=url,
            rest_personal_access_token=token,
            certificate=cert,
            timeout_sec=timeout)

More About

Exceptions

matlab.rest_function_service.exceptions.InvalidSchemeError	Raised if the request URL has a scheme other than https.
FileNotFoundError	Raised if the certificate file is not found.
TypeError	Raised if the timeout value is not an integer.
ValueError	Raised if the timeout value is less than or equal to zero.
HTTPException	Raised if the MATLAB REST function service returns a 4xx or 5xx HTTP status code.
matlab.rest_function_service.exceptions.MATLABException	Raised if the requested MATLAB function returns an error.

Version History

Introduced in R2026b