server.py

#!/usr/bin/env python
# -*- coding: utf8 -*-

__author__ = "Viktor Petersson"
__copyright__ = "Copyright 2012, WireLoad Inc"
__license__ = "Dual License: GPLv2 and Commercial License"
__version__ = "0.1.4"
__email__ = "vpetersson@wireload.net"

from datetime import datetime, timedelta
from functools import wraps
from hurry.filesize import size
from os import path, makedirs, getloadavg, statvfs, mkdir, getenv
from re import split as re_split
from sh import git
from subprocess import check_output
from uptime import uptime
import json
import os
import traceback
import uuid

from bottle import route, run, request, error, static_file, response
from bottle import HTTPResponse
from bottlehaml import haml_template

import db
import queries
import assets_helper

from utils import json_dump
from utils import get_node_ip
from utils import validate_url
from utils import url_fails
from utils import get_video_duration

from settings import settings, DEFAULTS
################################
# Utilities
################################


def make_json_response(obj):
    response.content_type = "application/json"
    return json_dump(obj)


def api_error(error):
    response.content_type = "application/json"
    response.status = 500
    return json_dump({'error': error})


def is_up_to_date():
    """
    Determine if there is any update available.
    Used in conjunction with check_update() in viewer.py.
    """

    sha_file = path.join(settings.get_configdir(), 'latest_screenly_sha')

    # Until this has been created by viewer.py, let's just assume we're up to date.
    if not os.path.exists(sha_file):
        return True

    try:
        with open(sha_file, 'r') as f:
            latest_sha = f.read().strip()
    except:
        latest_sha = None

    if latest_sha:
        try:
            check_sha = git('branch', '--contains', latest_sha)
            return 'master' in check_sha
        except:
            return False

    # If we weren't able to verify with remote side,
    # we'll set up_to_date to true in order to hide
    # the 'update available' message
    else:
        return True


def template(template_name, **context):
    """Screenly template response generator. Shares the
    same function signature as Bottle's template() method
    but also injects some global context."""

    # Add global contexts
    context['up_to_date'] = is_up_to_date()
    context['default_duration'] = settings['default_duration']
    context['use_24_hour_clock'] = settings['use_24_hour_clock']

    return haml_template(template_name, **context)


################################
# Model
################################


################################
# API
################################

def prepare_asset(request):

    data = request.POST or request.FORM or {}

    if 'model' in data:
        data = json.loads(data['model'])

    def get(key):
        val = data.get(key, '')
        if isinstance(val, unicode):
            return val.strip()
        elif isinstance(val, basestring):
            return val.strip().decode('utf-8')
        else:
            return val

    if all([get('name'),
            get('uri') or (request.files.file_upload != ""),
            get('mimetype')]):

        asset = {
            'name': get('name'),
            'mimetype': get('mimetype'),
            'asset_id': get('asset_id'),
            'is_enabled': get('is_enabled'),
            'nocache': get('nocache'),
        }

        uri = get('uri') or False

        if not asset['asset_id']:
            asset['asset_id'] = uuid.uuid4().hex

        try:
            file_upload = request.files.file_upload
            filename = file_upload.filename
        except AttributeError:
            file_upload = None
            filename = None

        if filename and 'web' in asset['mimetype']:
            raise Exception("Invalid combination. Can't upload a web resource.")

        if uri and filename:
            raise Exception("Invalid combination. Can't select both URI and a file.")

        if uri and not uri.startswith('/'):
            if not validate_url(uri):
                raise Exception("Invalid URL. Failed to add asset.")
            else:
                asset['uri'] = uri
        else:
            asset['uri'] = uri

        if filename:
            asset['uri'] = path.join(settings['assetdir'], asset['asset_id'])

            with open(asset['uri'], 'w') as f:
                while True:
                    chunk = file_upload.file.read(1024)
                    if not chunk:
                        break
                    f.write(chunk)

        if "video" in asset['mimetype']:
            video_duration = get_video_duration(asset['uri'])
            if video_duration:
                asset['duration'] = int(video_duration.total_seconds())
            else:
                asset['duration'] = 'N/A'
        else:
            # Crashes if it's not an int. We want that.
            asset['duration'] = int(get('duration'))

        if get('start_date'):
            asset['start_date'] = datetime.strptime(get('start_date').split(".")[0], "%Y-%m-%dT%H:%M:%S")
        else:
            asset['start_date'] = ""

        if get('end_date'):
            asset['end_date'] = datetime.strptime(get('end_date').split(".")[0], "%Y-%m-%dT%H:%M:%S")
        else:
            asset['end_date'] = ""

        if not asset['asset_id']:
            raise Exception

        if not asset['uri']:
            raise Exception

        return asset
    else:
        raise Exception("Not enough information provided. Please specify 'name', 'uri', and 'mimetype'.")


@route('/api/assets', method="GET")
def api_assets():
    assets = assets_helper.read(db_conn)
    return make_json_response(assets)


# api view decorator. handles errors
def api(view):
    @wraps(view)
    def api_view(*args, **kwargs):
        try:
            return make_json_response(view(*args, **kwargs))
        except HTTPResponse:
            raise
        except Exception as e:
            traceback.print_exc()
            return api_error(unicode(e))
    return api_view


@route('/api/assets', method="POST")
@api
def add_asset():
    asset = prepare_asset(request)
    if url_fails(asset['uri']):
        raise Exception("Could not retrieve file. Check the asset URL.")
    return assets_helper.create(db_conn, asset)


@route('/api/assets/:asset_id', method="GET")
@api
def edit_asset(asset_id):
    return assets_helper.read(db_conn, asset_id)


@route('/api/assets/:asset_id', method=["PUT", "POST"])
@api
def edit_asset(asset_id):
    return assets_helper.update(db_conn, asset_id, prepare_asset(request))


@route('/api/assets/:asset_id', method="DELETE")
@api
def remove_asset(asset_id):
    asset = assets_helper.read(db_conn, asset_id)
    try:
        if asset['uri'].startswith(settings['assetdir']):
            os.remove(asset['uri'])
    except OSError:
        pass
    assets_helper.delete(db_conn, asset_id)
    response.status = 204  # return an OK with no content


@route('/api/assets/order', method="POST")
@api
def playlist_order():
    "Receive a list of asset_ids in the order they should be in the playlist"
    for play_order, asset_id in enumerate(request.POST.get('ids', '').split(',')):
        assets_helper.update(db_conn, asset_id, {'asset_id': asset_id, 'play_order': play_order})

################################
# Views
################################


@route('/')
def viewIndex():
    return template('index')


@route('/settings', method=["GET", "POST"])
def settings_page():

    context = {'flash': None}

    if request.method == "POST":
        for field, default in DEFAULTS['viewer'].items():
            value = request.POST.get(field, default)
            if isinstance(default, bool):
                value = value == 'on'
            settings[field] = value
        try:
            settings.save()
            context['flash'] = {'class': "success", 'message': "Settings were successfully saved."}
        except IOError as e:
            context['flash'] = {'class': "error", 'message': e}
    else:
        settings.load()
    for field, default in DEFAULTS['viewer'].items():
        context[field] = settings[field]

    return template('settings', **context)


@route('/system_info')
def system_info():
    viewer_log_file = '/tmp/screenly_viewer.log'
    if path.exists(viewer_log_file):
        viewlog = check_output(['tail', '-n', '20', viewer_log_file]).split('\n')
    else:
        viewlog = ["(no viewer log present -- is only the screenly server running?)\n"]

    # Get load average from last 15 minutes and round to two digits.
    loadavg = round(getloadavg()[2], 2)

    try:
        run_tvservice = check_output(['tvservice', '-s'])
        display_info = re_split('\||,', run_tvservice.strip('state:'))
    except:
        display_info = False

    # Calculate disk space
    slash = statvfs("/")
    free_space = size(slash.f_bavail * slash.f_frsize)

    # Get uptime
    uptime_in_seconds = uptime()
    system_uptime = timedelta(seconds=uptime_in_seconds)

    return template('system_info', viewlog=viewlog, loadavg=loadavg, free_space=free_space, uptime=system_uptime, display_info=display_info)


@route('/splash_page')
def splash_page():
    my_ip = get_node_ip()
    if my_ip:
        ip_lookup = True
        url = "http://{}:{}".format(my_ip, settings.get_listen_port())
    else:
        ip_lookup = False
        url = "Unable to look up your installation's IP address."

    return template('splash_page', ip_lookup=ip_lookup, url=url)


@error(403)
def mistake403(code):
    return 'The parameter you passed has the wrong format!'


@error(404)
def mistake404(code):
    return 'Sorry, this page does not exist!'


################################
# Static
################################

@route('/static/:path#.+#', name='static')
def static(path):
    return static_file(path, root='static')


if __name__ == "__main__":
    # Make sure the asset folder exist. If not, create it
    if not path.isdir(settings['assetdir']):
        mkdir(settings['assetdir'])
    # Create config dir if it doesn't exist
    if not path.isdir(settings.get_configdir()):
        makedirs(settings.get_configdir())

    with db.conn(settings['database']) as conn:
        global db_conn
        db_conn = conn
        with db.cursor(db_conn) as c:
            c.execute(queries.exists_table)
            if c.fetchone() is None:
                c.execute(assets_helper.create_assets_table)
        run(host=settings.get_listen_ip(),
            port=settings.get_listen_port(), fast=True,
            reloader=True)