SaltStack grains error

Question

I have a strange problem with my Saltstack minions. I installed the minions on Ubuntu 16.04 and the connection to the master works fine. But as soon I try to make on my minion a state.apply I get a Jinja template error:

jenkins01-prod:
      Data failed to compile:
----------
Rendering SLS 'base:salt.minion' failed: Jinja error: coercing to Unicode: need string or buffer, int found
 /var/cache/salt/minion/files/base/salt/map.jinja(43):
 ---
   [...]
 {##
 Setup variable using grains['os_family'] based logic, only add 
key:values here
that differ from whats in defaults.yaml
 ##}
  {% set osrelease = salt['grains.get']('osrelease') %}
 {% set os_family_map = salt['grains.filter_by']({    <======================
'Debian':  {
  'pkgrepo': 'deb http://repo.saltstack.com/apt/' +
  salt['grains.get']('os')|lower + '/' + salt['grains.get']('osmajorrelease', osrelease) + '/amd64/latest ' + salt['grains.get']('oscodename') + ' main',
  'key_url': 'https://repo.saltstack.com/apt/' + salt['grains.get']('os')|lower + '/' + salt['grains.get']('osmajorrelease', osrelease) + '/amd64/latest/SALTSTACK-GPG-KEY.pub',
  'libgit2': 'libgit2-22',
 [...]
---
Traceback (most recent call last):

self._body_stream = list(template.root_render_func(context))
 File "/var/cache/salt/minion/files/base/salt/map.jinja", line 43, in top-level template code
{% set os_family_map = salt['grains.filter_by']({
TypeError: coercing to Unicode: need string or buffer, int found

I checked the grain items on the minion:

  os:
       Ubuntu
   os_family:
       Debian
   osarch:
       amd64
   oscodename:
       xenial
   osfinger:
       Ubuntu-16.04
   osfullname:
       Ubuntu
   osmajorrelease:
       16
   osrelease:
       16.04
   osrelease_info:
       - 16
       - 4

The hosts are EC2 instances, on a other host with the same setup it works fine. Attached you find the salt --versions-report: Salt Version:

         Salt: 2017.5.0-191-gb43b89c

 Dependency Versions:
       cffi: Not Installed
   cherrypy: Not Installed
   dateutil: 2.4.2
  docker-py: Not Installed
      gitdb: Not Installed
  gitpython: Not Installed
      ioflo: Not Installed
     Jinja2: 2.8
    libgit2: Not Installed
    libnacl: Not Installed
   M2Crypto: Not Installed
       Mako: 1.0.3
  msgpack-pure: Not Installed
msgpack-python: 0.4.6
mysql-python: Not Installed
  pycparser: Not Installed
   pycrypto: 2.6.1
pycryptodome: Not Installed
     pygit2: Not Installed
     Python: 2.7.12 (default, Nov 19 2016, 06:48:10)
python-gnupg: Not Installed
     PyYAML: 3.11
      PyZMQ: 15.2.0
       RAET: Not Installed
      smmap: Not Installed
    timelib: Not Installed
    Tornado: 4.2.1
        ZMQ: 4.1.4

  System Versions:
       dist: Ubuntu 16.04 xenial
    machine: x86_64
    release: 4.4.0-78-generic
     system: Linux
    version: Ubuntu 16.04 xenial

Answer 1

In recent Salt versions osmajorrelease grain was converted from string to integer (https://github.com/saltstack/salt/issues/35972). The error you get is saying that your Jinja template expects string but gets integer instead ( TypeError: coercing to Unicode: need string or buffer, int found ).

I'm not sure what exactly is being done inside of the state but one way to solve this would be to convert integer into string inside of your .jinja file. For example like this:

{% set osrelease = salt['grains.get']('osrelease')|string %}

Hope this helps!