add support for outputting sitemap index

README.md

@@ -83,6 +83,12 @@ $ python3 main.py --domain https://blog.lesite.us --num-workers 4
 $ python3 main.py --domain https://blog.lesite.us --auth
 ```
 
+#### Output sitemap index file
+***Sitemaps with over 50,000 URLs should be split into an index file that points to sitemap files that each contain 50,000 URLs or fewer.  Outputting as an index requires specifying an output file.  An index will only be output if a crawl has more than 50,000 URLs:***
+```
+$ python3 main.py --domain https://blog.lesite.us --as-index --output sitemap.xml
+```
+
 ## Docker usage
 
 #### Build the Docker image:

config.py

@@ -8,6 +8,11 @@
 """
 xml_footer = "</urlset>"
 
+sitemapindex_header = """<?xml version="1.0" encoding="UTF-8"?>
+<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
+"""
+sitemapindex_footer = "</sitemapindex>"
+
 crawler_user_agent = 'Sitemap crawler'
 
 # if used with --auth you have to provide username and password here for basic auth

crawler.py

@@ -2,6 +2,7 @@
 import concurrent.futures
 import base64
 from copy import copy
+import math
 
 import config
 import logging
@@ -21,6 +22,8 @@ class IllegalArgumentError(ValueError):
 
 class Crawler:
 
+	MAX_URLS_PER_SITEMAP = 50000
+
 	# Variables
 	parserobots = False
 	output 	= None
@@ -37,6 +40,7 @@ class Crawler:
 	auth = False
 
 	urls_to_crawl = set([])
+	url_strings_to_output = []
 	crawled_or_crawling = set([])
 	excluded = set([])
 
@@ -61,7 +65,7 @@ class Crawler:
 
 	def __init__(self, num_workers=1, parserobots=False, output=None,
 				 report=False ,domain="", exclude=[], skipext=[], drop=[],
-				 debug=False, verbose=False, images=False, auth=False):
+				 debug=False, verbose=False, images=False, auth=False, as_index=False):
 		self.num_workers = num_workers
 		self.parserobots = parserobots
 		self.output 	= output
@@ -73,7 +77,8 @@ def __init__(self, num_workers=1, parserobots=False, output=None,
 		self.debug		= debug
 		self.verbose    = verbose
 		self.images     = images
-		self.auth = auth
+		self.auth       = auth
+		self.as_index   = as_index
 
 		if self.debug:
 			log_level = logging.DEBUG
@@ -85,6 +90,7 @@ def __init__(self, num_workers=1, parserobots=False, output=None,
 		logging.basicConfig(level=log_level)
 
 		self.urls_to_crawl = {self.clean_link(domain)}
+		self.url_strings_to_output = []
 		self.num_crawled = 0
 
 		if num_workers <= 0:
@@ -104,10 +110,11 @@ def __init__(self, num_workers=1, parserobots=False, output=None,
 			except:
 				logging.error ("Output file not available.")
 				exit(255)
+		elif self.as_index:
+			logging.error("When specifying an index file as an output option, you must include an output file name")
+			exit(255)
 
 	def run(self):
-		print(config.xml_header, file=self.output_file)
-
 		if self.parserobots:
 			self.check_robots()
 
@@ -129,7 +136,8 @@ def run(self):
 
 		logging.info("Crawling has reached end of all found links")
 
-		print (config.xml_footer, file=self.output_file)
+		self.write_sitemap_output()
+
 
 
 	async def crawl_all_pending_urls(self, executor):
@@ -260,10 +268,8 @@ def __crawl(self, current_url):
 		lastmod = ""
 		if date:
 			lastmod = "<lastmod>"+date.strftime('%Y-%m-%dT%H:%M:%S+00:00')+"</lastmod>"
-
-		print ("<url><loc>"+self.htmlspecialchars(url.geturl())+"</loc>" + lastmod + image_list + "</url>", file=self.output_file)
-		if self.output_file:
-			self.output_file.flush()
+		url_string = "<url><loc>"+self.htmlspecialchars(url.geturl())+"</loc>" + lastmod + image_list + "</url>"
+		self.url_strings_to_output.append(url_string)
 
 		# Found links
 		links = self.linkregex.findall(msg)
@@ -333,6 +339,74 @@ def __crawl(self, current_url):
 
 			self.urls_to_crawl.add(link)
 
+	def write_sitemap_output(self):
+		are_multiple_sitemap_files_required = \
+			len(self.url_strings_to_output) > self.MAX_URLS_PER_SITEMAP
+
+		# When there are more than 50,000 URLs, the sitemap specification says we have
+		# to split the sitemap into multiple files using an index file that points to the
+		# location of each sitemap file.  For now, we require the caller to explicitly
+		# specify they want to create an index, even if there are more than 50,000 URLs,
+		# to maintain backward compatibility.
+		#
+		# See specification here:
+		# https://support.google.com/webmasters/answer/183668?hl=en
+		if are_multiple_sitemap_files_required and self.as_index:
+			self.write_index_and_sitemap_files()
+		else:
+			self.write_single_sitemap()
+
+	def write_single_sitemap(self):
+		self.write_sitemap_file(self.output_file, self.url_strings_to_output)
+
+	def write_index_and_sitemap_files(self):
+		sitemap_index_filename, sitemap_index_extension = os.path.splitext(self.output)
+
+		num_sitemap_files = math.ceil(len(self.url_strings_to_output) / self.MAX_URLS_PER_SITEMAP)
+		sitemap_filenames = []
+		for i in range(0, num_sitemap_files):
+			# name the individual sitemap files based on the name of the index file
+			sitemap_filename = sitemap_index_filename + '-' + str(i) + sitemap_index_extension
+			sitemap_filenames.append(sitemap_filename)
+
+		self.write_sitemap_index(sitemap_filenames)
+
+		for i, sitemap_filename in enumerate(sitemap_filenames):
+			self.write_subset_of_urls_to_sitemap(sitemap_filename, i * self.MAX_URLS_PER_SITEMAP)
+
+	def write_sitemap_index(self, sitemap_filenames):
+		sitemap_index_file = self.output_file
+		print(config.sitemapindex_header, file=sitemap_index_file)
+		for sitemap_filename in sitemap_filenames:
+			sitemap_url = urlunsplit([self.scheme, self.target_domain, sitemap_filename, '', ''])
+			print("<sitemap><loc>" + sitemap_url + "</loc>""</sitemap>", file=sitemap_index_file)
+		print(config.sitemapindex_footer, file=sitemap_index_file)
+
+	def write_subset_of_urls_to_sitemap(self, filename, index):
+		# Writes a maximum of self.MAX_URLS_PER_SITEMAP urls to a sitemap file
+		#
+		# filename: name of the file to write the sitemap to
+		# index:    zero-based index from which to start writing url strings contained in
+		#           self.url_strings_to_output
+		try:
+			sitemap_file = open(filename, 'w')
+		except:
+			logging.error("Could not open sitemap file that is part of index.")
+			exit(255)
+
+		start_index = index
+		end_index = (index + self.MAX_URLS_PER_SITEMAP)
+		sitemap_url_strings = self.url_strings_to_output[start_index:end_index]
+		self.write_sitemap_file(sitemap_file, sitemap_url_strings)
+
+	@staticmethod
+	def write_sitemap_file(file, url_strings):
+		print(config.xml_header, file=file)
+
+		for url_string in url_strings:
+			print (url_string, file=file)
+
+		print (config.xml_footer, file=file)
 
 	def clean_link(self, link):
 		parts = list(urlsplit(link))

main.py

@@ -15,6 +15,7 @@
 parser.add_argument('--auth', action="store_true", default=False, help="Enable basic authorisation while crawling")
 parser.add_argument('-v', '--verbose', action="store_true", help="Enable verbose output")
 parser.add_argument('--output', action="store", default=None, help="Output file")
+parser.add_argument('--as-index', action="store_true", default=False, required=False, help="Outputs sitemap as index and multiple sitemap files if crawl results in more than 50,000 links (uses filename in --output as name of index file)")
 parser.add_argument('--exclude', action="append", default=[], required=False, help="Exclude Url if contain")
 parser.add_argument('--drop', action="append", default=[], required=False, help="Drop a string from the url")
 parser.add_argument('--report', action="store_true", default=False, required=False, help="Display a report")