Iris/mopidy_iris/handlers.py

from datetime import datetime
from tornado.escape import json_encode, json_decode
import tornado.ioloop
import tornado.web
import tornado.websocket
import tornado.template
import logging
import json
import time
import asyncio

from .mem import iris

logger = logging.getLogger(__name__)


class WebsocketHandler(tornado.websocket.WebSocketHandler):

    # initiate (not the actual object __init__, but run shortly after)
    def initialize(self, core, config):
        self.core = core
        self.config = config
        self.ioloop = tornado.ioloop.IOLoop.current()
        iris.ioloop = self.ioloop  # Make available elsewhere in the Frontend

    def check_origin(self, origin):
        return True

    def open(self):

        # Get the client's IP. If it's local, then use it's proxy origin
        ip = self.request.remote_ip
        if ip == "127.0.0.1" and hasattr(
            self.request.headers, "X-Forwarded-For"
        ):
            ip = self.request.headers["X-Forwarded-For"]

        # Construct our initial client object, and add to our list of
        # connections
        client = {
            "connection_id": iris.generateGuid(),
            "ip": ip,
            "created": datetime.strftime(datetime.now(), "%Y-%m-%d %H:%M:%S"),
        }

        self.connection_id = client["connection_id"]

        iris.add_connection(connection=self, client=client)

    async def on_message(self, message):
        logger.debug("Iris websocket message received: " + message)

        message = json_decode(message)

        if "id" in message:
            id = message["id"]
        else:
            id = None

        if "jsonrpc" not in message:
            self.handle_result(
                id=id,
                error={
                    "id": id,
                    "code": 32602,
                    "message": (
                        "Invalid JSON-RPC request (missing ",
                        "property 'jsonrpc')",
                    ),
                },
            )

        if "params" in message:
            params = message["params"]

            # Handle hard-coded connection_id in messages
            # Otherwise include the origin connection of this message
            if "connection_id" not in params:
                message["params"]["connection_id"] = self.connection_id
        else:
            params = {}

        # call the method, as specified in payload
        if "method" in message:

            # make sure the method exists
            if hasattr(iris, message["method"]):
                try:

                    # For async methods we need to await, but it must be
                    # ommited for syncronous methods
                    if asyncio.iscoroutinefunction(
                        getattr(iris, message["method"])
                    ):
                        await getattr(iris, message["method"])(
                            ioloop=self.ioloop,
                            data=params,
                            callback=lambda response, error=False: self.handle_result(
                                id=id,
                                method=message["method"],
                                response=response,
                                error=error,
                            ),
                        )
                    else:
                        getattr(iris, message["method"])(
                            ioloop=self.ioloop,
                            data=params,
                            callback=lambda response, error=False: self.handle_result(
                                id=id,
                                method=message["method"],
                                response=response,
                                error=error,
                            ),
                        )
                except Exception as e:  # noqa: B036
                    logger.error(str(e))

            else:
                self.handle_result(
                    error={
                        "id": id,
                        "code": 32601,
                        "message": 'Method "'
                        + message["method"]
                        + '" does not exist',
                    },
                    id=id,
                )
                return
        else:
            self.handle_result(
                error={
                    "id": id,
                    "code": 32602,
                    "message": "Method key missing from request",
                },
                id=id,
            )
            return

    def on_close(self):
        iris.remove_connection(connection_id=self.connection_id)

    ##
    # Handle a response from our core
    # This is just our callback from an Async request
    ##
    def handle_result(self, *args, **kwargs):
        id = kwargs.get("id", False)
        method = kwargs.get("method", None)
        response = kwargs.get("response", None)
        error = kwargs.get("error", None)
        request_response = {"id": id, "jsonrpc": "2.0", "method": method}

        # We've been given an error
        if error:
            error["id"] = id
            request_response["error"] = error

        # We've been handed an AsyncHTTPClient callback. This is the case
        # when our request calls subsequent external requests (eg Spotify,
        # Genius)
        elif isinstance(response, tornado.httpclient.HTTPResponse):
            request_response["result"] = response.body

        # Just a regular json object, so not an external request
        else:
            request_response["result"] = response

        # Respond to the original request
        data = request_response
        data["recipient"] = self.connection_id
        iris.send_message(data=data)


class HttpHandler(tornado.web.RequestHandler):
    def set_default_headers(self):
        self.set_header("Access-Control-Allow-Origin", "*")
        self.set_header(
            "Access-Control-Allow-Headers",
            (
                "Origin, X-Requested-With, Content-Type, Accept, "
                "Authorization, Client-Security-Token, Accept-Encoding"
            ),
        )

    def initialize(self, core, config):
        self.core = core
        self.config = config
        self.ioloop = tornado.ioloop.IOLoop.current()

    # Options request
    # This is a preflight request for CORS requests
    def options(self, slug=None):
        self.set_status(204)
        self.finish()

    async def get(self, slug=None):

        id = int(time.time())

        # make sure the method exists
        if hasattr(iris, slug):
            try:

                # For async methods we need to await, but it must be ommited
                # for syncronous methods
                if asyncio.iscoroutinefunction(getattr(iris, slug)):
                    await getattr(iris, slug)(
                        ioloop=self.ioloop,
                        request=self,
                        callback=lambda response, error=False: self.handle_result(
                            id=id, method=slug, response=response, error=error
                        ),
                    )
                else:
                    getattr(iris, slug)(
                        ioloop=self.ioloop,
                        request=self,
                        callback=lambda response, error=False: self.handle_result(
                            id=id, method=slug, response=response, error=error
                        ),
                    )
            except Exception as e:  # noqa: B036
                logger.error(str(e))

        else:
            self.handle_result(
                id=id,
                error={
                    "code": 32601,
                    "message": "Method " + slug + " does not exist",
                },
            )
            return

    async def post(self, slug=None):

        id = int(time.time())

        try:
            params = json.loads(self.request.body.decode("utf-8"))
        except BaseException:  # noqa: B036
            self.handle_result(
                id=id,
                error={"code": 32700, "message": "Missing or invalid payload"},
            )
            return

        # make sure the method exists
        if hasattr(iris, slug):
            try:
                if asyncio.iscoroutinefunction(getattr(iris, slug)):
                    await getattr(iris, slug)(
                        data=params,
                        request=self.request,
                        callback=lambda response=False, error=False: self.handle_result(
                            id=id, method=slug, response=response, error=error
                        ),
                    )
                else:
                    getattr(iris, slug)(
                        data=params,
                        request=self.request,
                        callback=lambda response=False, error=False: self.handle_result(
                            id=id, method=slug, response=response, error=error
                        ),
                    )

            except tornado.web.HTTPError:
                self.handle_result(
                    id=id,
                    error={"code": 32601, "message": "Invalid JSON payload"},
                )
                return

        else:
            self.handle_result(
                id=id,
                error={
                    "code": 32601,
                    "message": "Method " + slug + " does not exist",
                },
            )
            return

    ##
    # Handle a response from our core
    # This is just our callback from an Async request
    ##
    def handle_result(self, *args, **kwargs):
        id = kwargs.get("id", None)
        method = kwargs.get("method", None)
        response = kwargs.get("response", None)
        error = kwargs.get("error", None)
        request_response = {"id": id, "jsonrpc": "2.0", "method": method}

        if error:
            request_response["error"] = error
            self.set_status(400)

        # We've been handed an AsyncHTTPClient callback. This is the case
        # when our request calls subsequent external requests.
        # We don't need to wrap non-HTTPResponse responses as these are dicts
        elif isinstance(response, tornado.httpclient.HTTPResponse):

            # Digest JSON responses into JSON
            content_type = response.headers.get("Content-Type")
            if content_type.startswith(
                "application/json"
            ) or content_type.startswith("text/json"):
                body = json.loads(response.body)

            # Non-JSON so just copy as-is
            else:
                body = json_encode(response.body)

            request_response["result"] = body

        # Regular ol successful response
        else:
            request_response["result"] = response

        # Write our response

        self.write(request_response)
        self.finish()


##
# Customised handler for react router URLS
#
# This routes all URLs to the same path, so that React can handle the path etc
##
class ReactRouterHandler(tornado.web.StaticFileHandler):
    def initialize(self, path):
        self.path = str(path)
        self.absolute_path = path
        self.dirname = path.parent
        self.filename = path.name
        super().initialize(self.dirname)

    def get(self, path=None, include_body=True):
        return super().get(self.path, include_body)