Update scraper.py

scraper.py

@@ -1,51 +1,141 @@
 # -*- coding: utf-8 -*-
 
+#### IMPORTS 1.0
+
+import os
+import re
 import scraperwiki
 import urllib2
 from datetime import datetime
 from bs4 import BeautifulSoup
 
-# Set up variables
+#### FUNCTIONS 1.0
+
+def validateFilename(filename):
+    filenameregex = '^[a-zA-Z0-9]+_[a-zA-Z0-9]+_[a-zA-Z0-9]+_[0-9][0-9][0-9][0-9]_[0-9QY][0-9]$'
+    dateregex = '[0-9][0-9][0-9][0-9]_[0-9QY][0-9]'
+    validName = (re.search(filenameregex, filename) != None)
+    found = re.search(dateregex, filename)
+    if not found:
+        return False
+    date = found.group(0)
+    now = datetime.now()
+    year, month = date[:4], date[5:7]
+    validYear = (2000 <= int(year) <= now.year)
+    if 'Q' in date:
+        validMonth = (month in ['Q0', 'Q1', 'Q2', 'Q3', 'Q4'])
+    elif 'Y' in date:
+        validMonth = (month in ['Y1'])
+    else:
+        try:
+            validMonth = datetime.strptime(date, "%Y_%m") < now
+        except:
+            return False
+    if all([validName, validYear, validMonth]):
+        return True
+
+
+def validateURL(url):
+    try:
+        r = urllib2.urlopen(url)
+        count = 1
+        while r.getcode() == 500 and count < 4:
+            print ("Attempt {0} - Status code: {1}. Retrying.".format(count, r.status_code))
+            count += 1
+            r = urllib2.urlopen(url)
+        sourceFilename = r.headers.get('Content-Disposition')
+
+        if sourceFilename:
+            ext = os.path.splitext(sourceFilename)[1].replace('"', '').replace(';', '').replace(' ', '')
+        else:
+            ext = os.path.splitext(url)[1]
+        validURL = r.getcode() == 200
+        validFiletype = ext.lower() in ['.csv', '.xls', '.xlsx']
+        return validURL, validFiletype
+    except:
+        print ("Error validating URL.")
+        return False, False
+
+
+def validate(filename, file_url):
+    validFilename = validateFilename(filename)
+    validURL, validFiletype = validateURL(file_url)
+    if not validFilename:
+        print filename, "*Error: Invalid filename*"
+        print file_url
+        return False
+    if not validURL:
+        print filename, "*Error: Invalid URL*"
+        print file_url
+        return False
+    if not validFiletype:
+        print filename, "*Error: Invalid filetype*"
+        print file_url
+        return False
+    return True
+
+
+def convert_mth_strings ( mth_string ):
+    month_numbers = {'JAN': '01', 'FEB': '02', 'MAR':'03', 'APR':'04', 'MAY':'05', 'JUN':'06', 'JUL':'07', 'AUG':'08', 'SEP':'09','OCT':'10','NOV':'11','DEC':'12' }
+    for k, v in month_numbers.items():
+        mth_string = mth_string.replace(k, v)
+    return mth_string
+
+#### VARIABLES 1.0
+
 entity_id = "E5036_ELBC_gov"
 url = "http://www.ealing.gov.uk/info/200687/council_budgets_and_spending/864/council_spending_over_500"
+errors = 0
+data = []
+
+#### READ HTML 1.0
 
-# Set up functions
-def convert_mth_strings ( mth_string ):
-	month_numbers = {'JAN': '01', 'FEB': '02', 'MAR':'03', 'APR':'04', 'MAY':'05', 'JUN':'06', 'JUL':'07', 'AUG':'08', 'SEP':'09','OCT':'10','NOV':'11','DEC':'12' }
-	#loop through the months in our dictionary
-	for k, v in month_numbers.items():
-		#then replace the word with the number
-		mth_string = mth_string.replace(k, v)
-	return mth_string
-
-# pull down the content from the webpage
 html = urllib2.urlopen(url)
-soup = BeautifulSoup(html)
+soup = BeautifulSoup(html, 'lxml')
+
+
+#### SCRAPE DATA
 
-# find all entries with the required class
 pageLinks = soup.findAll('a', href=True)
 
 for pageLink in pageLinks:
-	href = pageLink['href']
-	if '/downloads/download/' in href:
-	  	# add the right prefix onto the url
-	  	pageUrl = href.replace("/downloads","http://www.ealing.gov.uk/downloads")
-	  	html2 = urllib2.urlopen(pageUrl)
-	  	soup2 = BeautifulSoup(html2)
-	  	linkBlock = soup2.find('ul',{'class':'list'})
-	  	links = linkBlock.findAll('a')
-	  	for link in links:
-		  	fileUrl = link['href']
-		  	title = link.contents[0]
-			title = title.upper().strip()
-			if '2010/11' in title:
-				print 'not single months'
-			else:
-				# create the right strings for the new filename
-				csvYr = title.split(' ')[1]
-				csvMth = title.split(' ')[0][:3]
-				csvMth = convert_mth_strings(csvMth);
-		  		filename = entity_id + "_" + csvYr + "_" + csvMth
-		  		todays_date = str(datetime.now())
-		  		scraperwiki.sqlite.save(unique_keys=['l'], data={"l": fileUrl, "f": filename, "d": todays_date })
-		  		print filename
+    href = pageLink['href']
+    if '/downloads/download/' in href:
+        pageUrl = href.replace("/downloads","http://www.ealing.gov.uk/downloads")
+        html2 = urllib2.urlopen(pageUrl)
+        soup2 = BeautifulSoup(html2, 'lxml')
+        linkBlock = soup2.find('ul',{'class':'list'})
+        links = linkBlock.findAll('a')
+        for link in links:
+            fileUrl = link['href']
+            title = link.contents[0]
+            title = title.upper().strip()
+            if '2010/11' in title:
+                pass
+            else:
+                csvYr = title.split(' ')[1]
+                csvMth = title.split(' ')[0][:3]
+                csvMth = convert_mth_strings(csvMth.upper())
+                data.append([csvYr, csvMth, fileUrl])
+
+#### STORE DATA 1.0
+
+for row in data:
+    csvYr, csvMth, url = row
+    filename = entity_id + "_" + csvYr + "_" + csvMth
+    todays_date = str(datetime.now())
+    file_url = url.strip()
+
+    valid = validate(filename, file_url)
+
+    if valid == True:
+        scraperwiki.sqlite.save(unique_keys=['l'], data={"l": file_url, "f": filename, "d": todays_date })
+        print filename
+    else:
+        errors += 1
+
+if errors > 0:
+    raise Exception("%d errors occurred during scrape." % errors)
+
+
+#### EOF