cve-update-db: Use std library instead of urllib3

urllib3 was used in this recipe but it was not set as a
dependency. As it is not specifically needed, rewrite the recipe with
urllib from the standard library.

(From OE-Core rev: c0eabd30d7b9c2517f4ec9229640be421ecc8a5e)

Signed-off-by: Pierre Le Magourou <pierre.lemagourou@softbankrobotics.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/meta/cve-update-db.bb

@@ -19,7 +19,7 @@ python do_populate_cve_db() {
     Update NVD database with json data feed
     """
 
-    import sqlite3, urllib3, shutil, gzip, re
+    import sqlite3, urllib, shutil, gzip, re
     from datetime import date
 
     BASE_URL = "https://nvd.nist.gov/feeds/json/cve/1.0/nvdcve-1.0-"
@@ -33,16 +33,14 @@ python do_populate_cve_db() {
 
     initialize_db(c)
 
-    http = urllib3.PoolManager()
-
     for year in range(YEAR_START, date.today().year + 1):
         year_url = BASE_URL + str(year)
         meta_url = year_url + ".meta"
         json_url = year_url + ".json.gz"
 
         # Retrieve meta last modified date
-        with http.request('GET', meta_url, preload_content=False) as r:
-            date_line = str(r.data.splitlines()[0])
+        with urllib.request.urlopen(meta_url) as r:
+            date_line = str(r.read().splitlines()[0])
             last_modified = re.search('lastModifiedDate:(.*)', date_line).group(1)
 
         # Compare with current db last modified date
@@ -50,7 +48,7 @@ python do_populate_cve_db() {
         meta = c.fetchone()
         if not meta or meta[0] != last_modified:
             # Update db with current year json file
-            with http.request('GET', json_url, preload_content=False) as r, open(JSON_TMPFILE, 'wb') as tmpfile:
+            with urllib.request.urlopen(json_url) as r, open(JSON_TMPFILE, 'wb') as tmpfile:
                 shutil.copyfileobj(r, tmpfile)
             with gzip.open(JSON_TMPFILE, 'rt') as jsonfile:
                 update_db(c, jsonfile)