sysvitals/api/server.py

#!/usr/bin/env python

import copy
import datetime
import errno
import json
import os
from os import path
import traceback
import urlparse
import warnings

warnings.filterwarnings('ignore', 'libevent')
import gevent.pywsgi

import fileio
import reloader

DATA_DIR = path.expanduser('~/sysvitals_data')
handlers = None

def main():
	global handlers
	handlers = {
		'data': get_data,
		'datum': post_datum,
	}
	server = gevent.pywsgi.WSGIServer(('0.0.0.0', 8892), application)
	reloader.init(server)
	server.serve_forever()

def application(environ, start_response):
	try:
		split = environ['PATH_INFO'][1:].split('/')
		qs = environ['QUERY_STRING']
		if qs:
			query = urlparse.parse_qs(qs, True, True)
			for k, v in query.items():
				if len(v) > 1:
					start_response('400 Bad Request', [('Content-type', 'text/plain')])
					return ['duplicate query parameter: ' + k]
				query[k] = v[0]
		else:
			query = {}
		if split[0] == 'v1':
			handler = handlers.get(split[2])
			if handler:
				body = json.dumps(handler(split, query, environ))
				start_response('200 OK', [('Content-type', 'application/json')])
				return [body]
			else:
				print 'no handler for', split
		else:
			print 'split was', split
		start_response('404 Not Found', [('Content-type', 'text/plain')])
		return ['404 Not Found']
	except:
		traceback.print_exc()
		start_response('500 Internal Server Error', [('Content-type', 'text/plain')])
		return ['ruh roh']

def get_data(split, query, environ):
	group = int(split[1])
	server_id = int(split[3])
	start = datetime.datetime.strptime(query['start'], '%Y-%m-%d').date()
	end = datetime.datetime.strptime(query['end'], '%Y-%m-%d').date()

	server_dir = path.join(DATA_DIR, str(group), str(server_id))
	rval = {}
	c = start
	while c <= end:
		date_str = c.isoformat()
		with open(path.join(server_dir, date_str), 'r') as f:
			stats = fileio.read_stats(f)
			rval[date_str] = stats
		c += datetime.timedelta(days=1)
	return rval

def post_datum(split, query, environ):
	group = int(split[1])
	server_id = int(split[3])
	body = json.load(environ['wsgi.input'])

	server_dir = path.join(DATA_DIR, str(group), str(server_id))
	try:
		os.makedirs(server_dir)
	except OSError as e:
		if e.errno != errno.EEXIST:
			raise

	# we floor to the minute, so this rounds to the nearest minute
	now = datetime.datetime.utcnow() + datetime.timedelta(seconds=29)
	data_path = path.join(server_dir, now.date().isoformat())
	try:
		with open(data_path, 'r') as f:
			stats = fileio.read_stats(f)
	except IOError as e:
		if e.errno != errno.ENOENT:
			raise
		stats = copy.deepcopy(fileio.TEMPLATE)

	index = now.hour * 60 + now.minute
	data = {}
	for field, subfields in stats.items():
		field_data = {}
		if field == 'disk':
			disk = stats['disk']
			for mountpoint, datum in body['disk'].items(): # iterate through body to get new mountpoints
				disk.setdefault(mountpoint, {'total': [-1] * 1440, 'used': [-1] * 1440})
				field_data[mountpoint] = {}
				for subfield, array in disk[mountpoint].items():
					array = list(array)
					array[index] = datum[subfield]
					field_data[mountpoint][subfield] = array
		else:
			for subfield, array in subfields.items():
				array = list(array)
				array[index] = body[field][subfield]
				field_data[subfield] = array
		data[field] = field_data

	with open(data_path, 'w') as f:
		fileio.write_datum(f, data)
	return {'status': 'ok'}

main()