pandemonium_engine_docs/usage/networking/http_client_class.md

4.1 KiB

HTTP client class

HTTPClient provides low-level access to HTTP communication. For a higher-level interface, you may want to take a look at HTTPRequest first, which has a tutorial available here ( doc_http_request_class ).

Warning:

When exporting to Android, make sure to enable the `INTERNET`
permission in the Android export preset before exporting the project or
using one-click deploy. Otherwise, network communication of any kind will be
blocked by Android.

Here's an example of using the HTTPClient class. It's just a script, so it can be run by executing:

console GDScript

    c:\pandemonium> pandemonium -s http_test.gd

It will connect and fetch a website.

gdscript GDScript

    extends SceneTree

    # HTTPClient demo
    # This simple class can do HTTP requests; it will not block, but it needs to be polled.

    func _init():
        var err = 0
        var http = HTTPClient.new() # Create the Client.

        err = http.connect_to_host("www.php.net", 80) # Connect to host/port.
        assert(err == OK) # Make sure connection is OK.

        # Wait until resolved and connected.
        while http.get_status() == HTTPClient.STATUS_CONNECTING or http.get_status() == HTTPClient.STATUS_RESOLVING:
            http.poll()
            print("Connecting...")
            if not OS.has_feature("web"):
                OS.delay_msec(500)
            else:
                yield(Engine.get_main_loop(), "idle_frame")

        assert(http.get_status() == HTTPClient.STATUS_CONNECTED) # Check if the connection was made successfully.

        # Some headers
        var headers = [
            "User-Agent: Pirulo/1.0 (Pandemonium)",
            "Accept: */*"
        ]

        err = http.request(HTTPClient.METHOD_GET, "/ChangeLog-5.php", headers) # Request a page from the site (this one was chunked..)
        assert(err == OK) # Make sure all is OK.

        while http.get_status() == HTTPClient.STATUS_REQUESTING:
            # Keep polling for as long as the request is being processed.
            http.poll()
            print("Requesting...")
            if OS.has_feature("web"):
                # Synchronous HTTP requests are not supported on the web,
                # so wait for the next main loop iteration.
                yield(Engine.get_main_loop(), "idle_frame")
            else:
                OS.delay_msec(500)

        assert(http.get_status() == HTTPClient.STATUS_BODY or http.get_status() == HTTPClient.STATUS_CONNECTED) # Make sure request finished well.

        print("response? ", http.has_response()) # Site might not have a response.

        if http.has_response():
            # If there is a response...

            headers = http.get_response_headers_as_dictionary() # Get response headers.
            print("code: ", http.get_response_code()) # Show response code.
            print("**headers:\\n", headers) # Show headers.

            # Getting the HTTP Body

            if http.is_response_chunked():
                # Does it use chunks?
                print("Response is Chunked!")
            else:
                # Or just plain Content-Length
                var bl = http.get_response_body_length()
                print("Response Length: ", bl)

            # This method works for both anyway

            var rb = PoolByteArray() # Array that will hold the data.

            while http.get_status() == HTTPClient.STATUS_BODY:
                # While there is body left to be read
                http.poll()
                # Get a chunk.
                var chunk = http.read_response_body_chunk()
                if chunk.size() == 0:
                    if not OS.has_feature("web"):
                        # Got nothing, wait for buffers to fill a bit.
                        OS.delay_usec(1000)
                    else:
                        yield(Engine.get_main_loop(), "idle_frame")
                else:
                    rb = rb + chunk # Append to read buffer.
            # Done!

            print("bytes got: ", rb.size())
            var text = rb.get_string_from_ascii()
            print("Text: ", text)

        quit()