update.py

#!/usr/bin/python2
import os
import subprocess
import time
import json
import plistlib


def oneDaySinceLastCheck():
    '''
    Check whether it's been 24 hours since the last github query.
    We keep track of this through the modification time of this file,
    which is updated every time we query github.
    '''
    lastCheck = os.path.getmtime(__file__)
    if time.time() > 24*60*60 + lastCheck:
        subprocess.call(['/usr/bin/touch', __file__])
        return True
    else:
        return False


def updateAvailable(latestVersion):
    '''
    Check whether the latest version is ahead of the current version.
    '''
    currentVersion = plistlib.readPlist(os.path.dirname(__file__) + '/info.plist')['version']    
    if str(currentVersion).lower().strip() == str(latestVersion).lower().strip():
        return False
    else:
        return True


def userWantsUpdate(updateNotes):
    '''
    Show user a confirmation dialog.
    '''
    retval = subprocess.call(['/usr/bin/osascript', '-e', 'display dialog "An update is available for the Alfred Search Notes workflow. You can disable automatic update checks by editing the workflow.\n\nInformation about this release:\n\n%s" with title "Alfred Search Notes Workflow" buttons {"Cancel", "Download"} default button "Download" cancel button "Cancel"' % updateNotes, '2>/dev/null'])
    if retval == 0:
        return True
    else:
        return False
        
        
def update(updateUrl):
    '''
    Download and open new version of workflow.
    '''
    updateFile = '/tmp/Search.Notes.alfredworkflow'
    # --location is required in order to follow redirects
    curlRet = subprocess.call(['/usr/bin/curl', '--silent', '--location', '--output', updateFile, updateUrl])
    openRet = 1
    if curlRet == 0:
        openRet = subprocess.call(['/usr/bin/open', updateFile])
    if curlRet != 0 or openRet != 0:
        subprocess.call(['/usr/bin/osascript', '-e', 'display alert "Alfred Search Notes workflow failed to update." as critical', '2>/dev/null'])
    
    
if oneDaySinceLastCheck():
    latestUrl = 'https://api.github.com/repos/sballin/alfred-search-notes-app/releases/latest'
    latestFile = '/tmp/search_notes_latest_release.json'
    retval = subprocess.call(['/usr/bin/curl', '--silent', '--max-time', '30', '--output', latestFile, latestUrl])
    if retval == 0:
        with open(latestFile, 'r') as f:
            latest = json.load(f)
        latestVersion = latest['tag_name']
        updateNotes = latest['body']
        updateUrl = latest['assets'][0]['browser_download_url']
        
        if updateAvailable(latestVersion): 
            if userWantsUpdate(updateNotes):
                update(updateUrl)