Merge branch 'current' of github.com:vyos/vyos-build into current

README.md

@@ -43,7 +43,16 @@ There are several directories with their own purpose:
 
 ## Prerequisites
 
-To build a VyOS image, you need a machine that runs Debian Jessie. Other build hosts are not supported.
+To build a VyOS image, you need Debian8 "Jessie" environment (with jessie-backports repository). You can create it with [debootstrap](https://wiki.debian.org/Debootstrap) on Debian, Ubuntu and many distributions. To create Debian8 "Jessie" environment under vyos-chroot directory, run below commands.
+
+```
+$ sudo apt install debootstrap (Note: This is on Debian/Ubuntu, adjust it with your favorite distro package manager)
+$ sudo debootstrap jessie vyos-chroot
+$ sudo chroot vyos-chroot
+
+# echo "deb http://deb.debian.org/debian jessie-backports main" >> /etc/apt/sources.list
+# apt update
+```
 
 Several packages are required for building the ISO and all packages, namely python3, live-build, pbuilder, python3-pystache and devscripts.
 Individual packages may have other build dependencies. If some packages are missing, build scripts will tell you.

tools/get_latest_iso.py

@@ -0,0 +1,31 @@
+#!/usr/bin/env python3
+
+import os
+import sys
+from lxml import html
+from urllib.parse import unquote
+import requests
+
+BASE_URL = 'https://downloads.vyos.io/'
+PAGE_URL = BASE_URL+'?dir=rolling/current/amd64'
+
+
+def download():
+    page = requests.get(PAGE_URL)
+    tree = html.fromstring(page.content)
+    path = '//*[@id="directory-listing"]/li/a[1]/@href'
+    isos = [x for x in tree.xpath(path) if os.path.splitext(x)[1] == '.iso']
+    latest_iso_url = os.path.join(BASE_URL, isos[-1])
+    filename = unquote(os.path.basename(latest_iso_url))
+    print(filename)
+    if os.path.exists(filename):
+        print("{} already exists".format(filename))
+        sys.exit(0)
+    r = requests.get(latest_iso_url)
+    with open(filename, 'wb') as fd:
+        for chunk in r.iter_content(chunk_size=128):
+            fd.write(chunk)
+
+
+if __name__ == '__main__':
+    download()