java - Could someone explain what purpose an Interface inside an Azure function's parameter serves? - Stack Overflow

I'm working with Azure functions, and I noticed that the request parameter has the type of an Interface called HttpRequestMessage (see (1)). What exactly does this request variable contain? Is the HttpRequestMessage Interface prefix just a recipe for what the request variable should contain?

@FunctionName("Sales")
public HttpResponseMessage run(
        @HttpTrigger(
            name = "req",
            methods = {HttpMethod.POST}, 
            authLevel = AuthorizationLevel.ANONYMOUS) 
        (1) HttpRequestMessage<Optional<String>> request,
            @RequestParameterMap
        final ExecutionContext context) 

This post is somewhat related to a previous post I made: azure function test fails.

I'm working with Azure functions, and I noticed that the request parameter has the type of an Interface called HttpRequestMessage (see (1)). What exactly does this request variable contain? Is the HttpRequestMessage Interface prefix just a recipe for what the request variable should contain?

@FunctionName("Sales")
public HttpResponseMessage run(
        @HttpTrigger(
            name = "req",
            methods = {HttpMethod.POST}, 
            authLevel = AuthorizationLevel.ANONYMOUS) 
        (1) HttpRequestMessage<Optional<String>> request,
            @RequestParameterMap
        final ExecutionContext context) 

This post is somewhat related to a previous post I made: azure function test fails.

• java
• azure
• azure-functions

Share Improve this question Follow edited Jan 22 at 12:21 Admir asked Jan 21 at 14:49 AdmirAdmir 144 bronze badges 1

• Refer learn.microsoft.com/en-us/java/api/…. – Pravallika KV Commented Jan 22 at 3:34

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1 Answer 1

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As mentioned in MSDOC, the HttpRequestMessage<T> in Azure Functions represents a request which provides methods and properties to access the details of the HTTP request like:

• HTTP headers, allowing to access information like Content-Type, Authorization, etc.,
• Query parameters included in the HTTP request.

query = request.getQueryParameters().get("name");

• The HTTP methods like GET, POST, PUT, DELETE used for the request.
• URI for the request with the path and query string, which can be accessed through the RequestUri property.
• Body content of the HTTP request, which can be accessed using the getBody() method.

name = request.getBody().orElse(query);

Function code:

@FunctionName("HttpExample")
    public HttpResponseMessage run(
            @HttpTrigger(
                name = "req",
                methods = {HttpMethod.GET, HttpMethod.POST},
                authLevel = AuthorizationLevel.ANONYMOUS)
                HttpRequestMessage<Optional<String>> request,
            final ExecutionContext context) {
        context.getLogger().info("Java HTTP trigger processed a request.");

        final String query = request.getQueryParameters().get("name");
        final String name = request.getBody().orElse(query);

        if (name == null) {
            return request.createResponseBuilder(HttpStatus.BAD_REQUEST).body("Please pass a name on the query string or in the request body").build();
        } else {
            return request.createResponseBuilder(HttpStatus.OK).body("Hello, " + name).build();
        }
    }

Response:

Functions:

        HttpExample: [GET,POST] http://localhost:7071/api/HttpExample

For detailed output, run func with --verbose flag.
[2025-01-22T08:58:16.984Z] Worker process started and initialized.
[2025-01-22T08:58:20.063Z] Host lock lease acquired by instance ID '000000000000000000000000F72731CC'.
[2025-01-22T08:58:22.798Z] Executing 'Functions.HttpExample' (Reason='This function was programmatically called via the host APIs.', Id=20f02fae-1209-4bf5-b49e-e0c2e01e6e73)
[2025-01-22T08:58:23.117Z] Function "HttpExample" (Id: 20f02fae-1209-4bf5-b49e-e0c2e01e6e73) invoked by Java Worker
[2025-01-22T08:58:23.117Z] Java HTTP trigger processed a request.
[2025-01-22T08:58:23.331Z] Executed 'Functions.HttpExample' (Succeeded, Id=20f02fae-1209-4bf5-b49e-e0c2e01e6e73, Duration=590ms)