New Feature: support for autoFetch of urls deemed as pages by history api (pywb part) (#497)

* auto-fetch page fetch support:
- check for X-Wombat-History-Page header to indicate page url
- set title from X-Wombat-History-Title header, and attempt to parse <title> from response
- update auto-fetch workers in wombat
- update changelist, bump to 2.3.4

CHANGES.rst

@@ -1,3 +1,12 @@
+pywb 2.3.4 changelist
+~~~~~~~~~~~~~~~~~~~~~
+
+* Improvements to auto-fetch to support page fetch (webrecroder/wombat#5, #497)
+  - Support fetching page with ``X-Wombat-History-Page`` and title ``X-Wombat-History-Title`` headers present.
+  - Attempt to extract title and pass along with cdx to ``_add_history_page()`` callback in RewriterApp, to indicate a url is a page.
+  - General auto-fetch fixes: queue messages if worker not yet inited (in proxy mode), only parse <link> stylesheet hrefs as sheets.
+
+
 pywb 2.3.3 changelist
 ~~~~~~~~~~~~~~~~~~~~~
 

pywb/apps/rewriterapp.py

@@ -3,7 +3,7 @@ from io import BytesIO
 import requests
 from fakeredis import FakeStrictRedis
 
-from six.moves.urllib.parse import urlencode, urlsplit, urlunsplit
+from six.moves.urllib.parse import urlencode, urlsplit, urlunsplit, unquote
 from warcio.bufferedreaders import BufferedReader
 from warcio.recordloader import ArcWarcRecordLoader
 from warcio.timeutils import http_date_to_timestamp, timestamp_to_http_date
@@ -222,6 +222,13 @@ class RewriterApp(object):
         if proto:
             environ['wsgi.url_scheme'] = proto
 
+        history_page = environ.pop('HTTP_X_WOMBAT_HISTORY_PAGE', '')
+        if history_page:
+            wb_url.url = history_page
+            is_ajax = True
+        else:
+            is_ajax = self.is_ajax(environ)
+
         is_timegate = self._check_accept_dt(wb_url, environ)
 
         host_prefix = self.get_host_prefix(environ)
@@ -358,8 +365,6 @@ class RewriterApp(object):
         if self._add_range(record, wb_url, range_start, range_end):
             wb_url.mod = 'id_'
 
-        is_ajax = self.is_ajax(environ)
-
         if is_ajax:
             head_insert_func = None
             urlrewriter.rewrite_opts['is_ajax'] = True
@@ -392,6 +397,17 @@ class RewriterApp(object):
 
         status_headers, gen, is_rw = result
 
+        if history_page:
+            title = DefaultRewriter._extract_title(gen)
+            if not title:
+                title = unquote(environ.get('HTTP_X_WOMBAT_HISTORY_TITLE', ''))
+
+            if not title:
+                title = history_page
+
+            self._add_history_page(cdx, kwargs, title)
+            return WbResponse.json_response({'title': title})
+
         if setcookie_headers:
             status_headers.headers.extend(setcookie_headers)
 
@@ -660,6 +676,9 @@ class RewriterApp(object):
         else:
             return None
 
+    def _add_history_page(self, cdx, kwargs, doc_title):
+        pass
+
     def _add_custom_params(self, cdx, headers, kwargs, record):
         pass
 

pywb/rewrite/content_rewriter.py

@@ -18,6 +18,21 @@ WORKER_MODS = {"wkr_", "sw_"}  # type: Set[str]
 class BaseContentRewriter(object):
     CHARSET_REGEX = re.compile(b'<meta[^>]*?[\s;"\']charset\s*=[\s"\']*([^\s"\'/>]*)')
 
+    TITLE = re.compile(r'<\s*title\s*>(.*)<\s*\/\s*title\s*>', re.M | re.I | re.S)
+
+    @classmethod
+    def _extract_title(cls, gen):
+        title_res = list(gen)
+        if not title_res or not title_res[0]:
+            return
+
+        m = cls.TITLE.search(title_res[0].decode('utf-8'))
+        if not m:
+            return
+
+        title_res = m.group(1)
+        return title_res.strip()
+
     def __init__(self, rules_file, replay_mod=''):
         self.rules = []
         self.all_rewriters = []

pywb/static/autoFetchWorker.js

@@ -101,27 +101,36 @@ function fetchDoneOrErrored() {
   fetchFromQ();
 }
 
-function fetchURL(urlToBeFetched) {
+function fetchURL(toBeFetched) {
   runningFetches += 1;
-  fetch(urlToBeFetched)
+
+  var url;
+  var options;
+
+  if (typeof toBeFetched === 'object') {
+    url = toBeFetched.url;
+    options = toBeFetched.options;
+  } else {
+    url = toBeFetched;
+  }
+
+  fetch(url, options)
     .then(fetchDoneOrErrored)
     .catch(fetchDoneOrErrored);
 }
 
-function queueOrFetch(urlToBeFetched) {
-  if (
-    !urlToBeFetched ||
-    urlToBeFetched.indexOf(DataURLPrefix) === 0 ||
-    seen[urlToBeFetched] != null
-  ) {
+function queueOrFetch(toBeFetched) {
+  var url = typeof toBeFetched === 'object' ? toBeFetched.url : toBeFetched;
+
+  if (!url || url.indexOf(DataURLPrefix) === 0 || seen[url] != null) {
     return;
   }
-  seen[urlToBeFetched] = true;
+  seen[url] = true;
   if (runningFetches >= MaxRunningFetches) {
-    queue.push(urlToBeFetched);
+    queue.push(toBeFetched);
     return;
   }
-  fetchURL(urlToBeFetched);
+  fetchURL(toBeFetched);
 }
 
 function fetchFromQ() {

pywb/version.py

@@ -1,4 +1,4 @@
-__version__ = '2.3.3'
+__version__ = '2.3.4'
 
 if __name__ == '__main__':
     print(__version__)

wombat

@@ -1 +1 @@
-Subproject commit acfb37a74bee00c4c483befd7f756551b45b9333
+Subproject commit 5fdacc6cd4c89ee8cd1fcbd3fccd4907069050e3