
Conflicts: - doc/ref/configuration/master.rst - doc/ref/modules/all/index.rst - doc/topics/grains/index.rst - doc/topics/releases/2016.3.4.rst - doc/topics/spm/spm_formula.rst - doc/topics/tutorials/cron.rst - doc/topics/tutorials/index.rst - doc/topics/tutorials/stormpath.rst - salt/engines/slack.py - salt/log/handlers/fluent_mod.py - salt/modules/cyg.py - salt/modules/junos.py - salt/modules/namecheap_dns.py - salt/modules/namecheap_domains.py - salt/modules/namecheap_ns.py - salt/modules/namecheap_ssl.py - salt/modules/namecheap_users.py - salt/modules/reg.py - salt/modules/tomcat.py - salt/modules/vault.py - salt/modules/win_file.py - salt/modules/zpool.py - salt/output/highstate.py - salt/renderers/pass.py - salt/runners/cache.py - salt/states/boto_apigateway.py - salt/states/boto_iam.py - salt/states/boto_route53.py - salt/states/msteams.py - salt/states/reg.py - salt/states/win_iis.py - tests/integration/modules/test_cmdmod.py - tests/integration/states/test_user.py - tests/support/helpers.py - tests/unit/cloud/clouds/test_openstack.py - tests/unit/fileserver/test_gitfs.py - tests/unit/modules/test_junos.py - tests/unit/pillar/test_git.py - tests/unit/states/test_win_path.py - tests/unit/test_pillar.py - tests/unit/utils/test_format_call.py - tests/unit/utils/test_utils.py - tests/unit/utils/test_warnings.py
34 KiB
Understanding Jinja
Jinja is the default templating language in SLS files.
Jinja in States
Jinja is evaluated before YAML, which means it is evaluated before the States are run.
The most basic usage of Jinja in state files is using control structures to wrap conditional or redundant state elements:
{% if grains['os'] != 'FreeBSD' %}
tcsh:
pkg:
- installed
{% endif %}
motd:
file.managed:
{% if grains['os'] == 'FreeBSD' %}
- name: /etc/motd
{% elif grains['os'] == 'Debian' %}
- name: /etc/motd.tail
{% endif %}
- source: salt://motd
In this example, the first if block will only be evaluated on minions that aren't running FreeBSD, and the second block changes the file name based on the os grain.
Writing if-else blocks can lead to very redundant
state files however. In this case, using pillars<pillar>
, or using a previously defined
variable might be easier:
{% set motd = ['/etc/motd'] %}
{% if grains['os'] == 'Debian' %}
{% set motd = ['/etc/motd.tail', '/var/run/motd'] %}
{% endif %}
{% for motdfile in motd %}
{{ motdfile }}:
file.managed:
- source: salt://motd
{% endfor %}
Using a variable set by the template, the for loop will iterate over the list of MOTD files to update, adding a state block for each file.
The filter_by function can also be used to set variables based on grains:
{% set auditd = salt['grains.filter_by']({
'RedHat': { 'package': 'audit' },
'Debian': { 'package': 'auditd' },
}) %}
Include and Import
Includes and imports can be used to share common, reusable state configuration between state files and between files.
{% from 'lib.sls' import test %}
This would import the test
template variable or macro,
not the test
state element, from the file
lib.sls
. In the case that the included file performs checks
against grains, or something else that requires context, passing the
context into the included file is required:
{% from 'lib.sls' import test with context %}
Including Context During Include/Import
By adding with context
to the include/import directive,
the current context can be passed to an included/imported template.
{% import 'openssl/vars.sls' as ssl with context %}
Macros
Macros are helpful for eliminating redundant code. Macros are most useful as mini-templates to repeat blocks of strings with a few parameterized variables. Be aware that stripping whitespace from the template block, as well as contained blocks, may be necessary to emulate a variable return from the macro.
# init.sls
{% from 'lib.sls' import pythonpkg with context %}
python-virtualenv:
pkg.installed:
- name: {{ pythonpkg('virtualenv') }}
python-fabric:
pkg.installed:
- name: {{ pythonpkg('fabric') }}
# lib.sls
{% macro pythonpkg(pkg) -%}
{%- if grains['os'] == 'FreeBSD' -%}
py27-{{ pkg }}
{%- elif grains['os'] == 'Debian' -%}
python-{{ pkg }}
{%- endif -%}
{%- endmacro %}
This would define a macro that would return a string of the full package name, depending on the packaging system's naming convention. The whitespace of the macro was eliminated, so that the macro would return a string without line breaks, using whitespace control.
Template Inheritance
Template inheritance works fine from state files and files. The search path starts at the root of the state tree or pillar.
Errors
Saltstack allows raising custom errors using the raise
jinja function.
{{ raise('Custom Error') }}
When rendering the template containing the above statement, a
TemplateError
exception is raised, causing the rendering to
fail with the following message:
TemplateError: Custom Error
Filters
Saltstack extends builtin filters with these custom filters:
strftime
Converts any time related object into a time based string. It
requires valid strftime directives. An exhaustive list can be found
here
<strftime-strptime-behavior>
in the Python
documentation.
{% set curtime = None | strftime() %}
Fuzzy dates require the timelib Python module is installed.
{{ "2002/12/25"|strftime("%y") }}
{{ "1040814000"|strftime("%Y-%m-%d") }}
{{ datetime|strftime("%u") }}
{{ "tomorrow"|strftime }}
sequence
Ensure that parsed data is a sequence.
yaml_encode
Serializes a single object into a YAML scalar with any necessary handling for escaping special characters. This will work for any scalar YAML data type: ints, floats, timestamps, booleans, strings, unicode. It will not work for multi-objects such as sequences or maps.
{%- set bar = 7 %}
{%- set baz = none %}
{%- set zip = true %}
{%- set zap = 'The word of the day is "salty"' %}
{%- load_yaml as foo %}
bar: {{ bar|yaml_encode }}
baz: {{ baz|yaml_encode }}
baz: {{ zip|yaml_encode }}
baz: {{ zap|yaml_encode }}
{%- endload %}
In the above case {{ bar }}
and
{{ foo.bar }}
should be identical and
{{ baz }}
and {{ foo.baz }}
should be
identical.
yaml_dquote
Serializes a string into a properly-escaped YAML double-quoted string. This is useful when the contents of a string are unknown and may contain quotes or unicode that needs to be preserved. The resulting string will be emitted with opening and closing double quotes.
{%- set bar = '"The quick brown fox . . ."' %}
{%- set baz = 'The word of the day is "salty".' %}
{%- load_yaml as foo %}
bar: {{ bar|yaml_dquote }}
baz: {{ baz|yaml_dquote }}
{%- endload %}
In the above case {{ bar }}
and
{{ foo.bar }}
should be identical and
{{ baz }}
and {{ foo.baz }}
should be
identical. If variable contents are not guaranteed to be a string then
it is better to use yaml_encode
which handles all YAML
scalar types.
yaml_squote
Similar to the yaml_dquote
filter but with single
quotes. Note that YAML only allows special escapes inside double quotes
so yaml_squote
is not nearly as useful (viz. you likely
want to use yaml_encode
or yaml_dquote
).
to_bool
2017.7.0
Returns the logical value of an element.
Example:
{{ 'yes' | to_bool }}
{{ 'true' | to_bool }}
{{ 1 | to_bool }}
{{ 'no' | to_bool }}
Will be rendered as:
True
True
True
False
exactly_n_true
2017.7.0
Tests that exactly N items in an iterable are "truthy" (neither None, False, nor 0).
Example:
{{ ['yes', 0, False, 'True'] | exactly_n_true(2) }}
Returns:
True
exactly_one_true
2017.7.0
Tests that exactly one item in an iterable is "truthy" (neither None, False, nor 0).
Example:
{{ ['yes', False, 0, None] | exactly_one_true }}
Returns:
True
quote
2017.7.0
This text will be wrapped in quotes.
regex_search
2017.7.0
Scan through string looking for a location where this regular
expression produces a match. Returns None
in case there
were no matches found
Example:
{{ 'abcdefabcdef' | regex_search('BC(.*)', ignorecase=True) }}
Returns:
'defabcdef',) (
regex_match
2017.7.0
If zero or more characters at the beginning of string match this
regular expression, otherwise returns None
.
Example:
{{ 'abcdefabcdef' | regex_match('BC(.*)', ignorecase=True) }}
Returns:
None
uuid
2017.7.0
Return a UUID.
Example:
{{ 'random' | uuid }}
Returns:
3652b285-26ad-588e-a5dc-c2ee65edc804
is_list
2017.7.0
Return if an object is list.
Example:
{{ [1, 2, 3] | is_list }}
Returns:
True
is_iter
2017.7.0
Return if an object is iterable.
Example:
{{ [1, 2, 3] | is_iter }}
Returns:
True
min
2017.7.0
Return the minimum value from a list.
Example:
{{ [1, 2, 3] | min }}
Returns:
1
max
2017.7.0
Returns the maximum value from a list.
Example:
{{ [1, 2, 3] | max }}
Returns:
3
avg
2017.7.0
Returns the average value of the elements of a list
Example:
{{ [1, 2, 3] | avg }}
Returns:
2
union
2017.7.0
Return the union of two lists.
Example:
{{ [1, 2, 3] | union([2, 3, 4]) | join(', ') }}
Returns:
1, 2, 3, 4
intersect
2017.7.0
Return the intersection of two lists.
Example:
{{ [1, 2, 3] | intersect([2, 3, 4]) | join(', ') }}
Returns:
2, 3
difference
2017.7.0
Return the difference of two lists.
Example:
{{ [1, 2, 3] | difference([2, 3, 4]) | join(', ') }}
Returns:
1
symmetric_difference
2017.7.0
Return the symmetric difference of two lists.
Example:
{{ [1, 2, 3] | symmetric_difference([2, 3, 4]) | join(', ') }}
Returns:
1, 4
is_sorted
2017.7.0
Return is an iterable object is already sorted.
Example:
{{ [1, 2, 3] | is_sorted }}
Returns:
True
compare_lists
2017.7.0
Compare two lists and return a dictionary with the changes.
Example:
{{ [1, 2, 3] | compare_lists([1, 2, 4]) }}
Returns:
'new': 4, 'old': 3} {
compare_dicts
2017.7.0
Compare two dictionaries and return a dictionary with the changes.
Example:
{{ {'a': 'b'} | compare_lists({'a': 'c'}) }}
Returns:
'a': {'new': 'c', 'old': 'b'}} {
is_hex
2017.7.0
Return True if the value is hexazecimal.
Example:
{{ '0xabcd' | is_hex }}
{{ 'xyzt' | is_hex }}
Returns:
True
False
contains_whitespace
2017.7.0
Return True if a text contains whitespaces.
Example:
{{ 'abcd' | contains_whitespace }}
{{ 'ab cd' | contains_whitespace }}
Returns:
False
True
substring_in_list
2017.7.0
Return is a substring is found in a list of string values.
Example:
{{ 'abcd' | substring_in_list(['this', 'is', 'an abcd example']) }}
Returns:
True
check_whitelist_blacklist
2017.7.0
Check a whitelist and/or blacklist to see if the value matches it.
This filter can be used with either a whitelist or a blacklist individually, or a whitelist and a blacklist can be passed simultaneously.
If whitelist is used alone, value membership is checked against the
whitelist only. If the value is found, the function returns
True
. Otherwise, it returns False
.
If blacklist is used alone, value membership is checked against the
blacklist only. If the value is found, the function returns
False
. Otherwise, it returns True
.
If both a whitelist and a blacklist are provided, value membership in
the blacklist will be examined first. If the value is not found in the
blacklist, then the whitelist is checked. If the value isn't found in
the whitelist, the function returns False
.
Whitelist Example:
{{ 5 | check_whitelist_blacklist(whitelist=[5, 6, 7]) }}
Returns:
True
Blacklist Example:
{{ 5 | check_whitelist_blacklist(blacklist=[5, 6, 7]) }}
False
date_format
2017.7.0
Converts unix timestamp into human-readable string.
Example:
{{ 1457456400 | date_format }}
{{ 1457456400 | date_format('%d.%m.%Y %H:%M') }}
Returns:
2017-03-08
08.03.2017 17:00
to_num
2017.7.0
2018.3.0 Renamed from str_to_num
to
to_num
.
Converts a string to its numerical value.
Example:
{{ '5' | to_num }}
Returns:
5
to_bytes
2017.7.0
Converts string-type object to bytes.
Example:
{{ 'wall of text' | to_bytes }}
Note
This option may have adverse effects when using the default renderer,
yaml_jinja
. This is due to the fact that YAML requires
proper handling in regard to special characters. Please see the section
on YAML ASCII
support <yaml_plain_ascii>
in the YAML Idiosyncracies
<yaml-idiosyncrasies>
documentation for more
information.
json_encode_list
2017.7.0
2018.3.0 Renamed from json_decode_list
to
json_encode_list
. When you encode something you get bytes,
and when you decode, you get your locale's encoding (usually a
unicode
type). This filter was incorrectly-named when it
was added. json_decode_list
will be supported until the
Neon release.
Recursively encodes all string elements of the list to bytes.
Example:
{{ [1, 2, 3] | json_encode_list }}
Returns:
1, 2, 3] [
json_encode_dict
2017.7.0
2018.3.0 Renamed from json_decode_dict
to
json_encode_dict
. When you encode something you get bytes,
and when you decode, you get your locale's encoding (usually a
unicode
type). This filter was incorrectly-named when it
was added. json_decode_dict
will be supported until the
Neon release.
Recursively encodes all string items in the dictionary to bytes.
Example:
Assuming that pillar['foo']
contains
{u'a': u'\u0414'}
, and your locale is
en_US.UTF-8
:
{{ pillar['foo'] | json_encode_dict }}
Returns:
'a': '\xd0\x94'} {
random_hash
2017.7.0
2018.3.0 Renamed from rand_str
to
random_hash
to more accurately describe what the filter
does. rand_str
will be supported until the Neon
release.
Generates a random number between 1 and the number passed to the
filter, and then hashes it. The default hash type is the one specified
by the minion's hash_type
config option, but an alternate hash
type can be passed to the filter as an argument.
Example:
{% set num_range = 99999999 %}
{{ num_range | random_hash }}
{{ num_range | random_hash('sha512') }}
Returns:
43ec517d68b6edd3015b3edc9a11367b
d94a45acd81f8e3107d237dbc0d5d195f6a52a0d188bc0284c0763ece1eac9f9496fb6a531a296074c87b3540398dace1222b42e150e67c9301383fde3d66ae5
md5
2017.7.0
Return the md5 digest of a string.
Example:
{{ 'random' | md5 }}
Returns:
7ddf32e17a6ac5ce04a8ecbf782ca509
sha256
2017.7.0
Return the sha256 digest of a string.
Example:
{{ 'random' | sha256 }}
Returns:
a441b15fe9a3cf56661190a0b93b9dec7d04127288cc87250967cf3b52894d11
sha512
2017.7.0
Return the sha512 digest of a string.
Example:
{{ 'random' | sha512 }}
Returns:
811a90e1c8e86c7b4c0eef5b2c0bf0ec1b19c4b1b5a242e6455be93787cb473cb7bc9b0fdeb960d00d5c6881c2094dd63c5c900ce9057255e2a4e271fc25fef1
base64_encode
2017.7.0
Encode a string as base64.
Example:
{{ 'random' | base64_encode }}
Returns:
cmFuZG9t
base64_decode
2017.7.0
Decode a base64-encoded string.
{{ 'Z2V0IHNhbHRlZA==' | base64_decode }}
Returns:
get salted
hmac
2017.7.0
Verify a challenging hmac signature against a string / shared-secret. Returns a boolean value.
Example:
{{ 'get salted' | hmac('shared secret', 'eBWf9bstXg+NiP5AOwppB5HMvZiYMPzEM9W5YMm/AmQ=') }}
Returns:
True
http_query
2017.7.0
Return the HTTP reply object from a URL.
Example:
{{ 'http://jsonplaceholder.typicode.com/posts/1' | http_query }}
Returns:
{'body': '{
"userId": 1,
"id": 1,
"title": "sunt aut facere repellat provident occaecati excepturi option reprehenderit",
"body": "quia et suscipit\\nsuscipit recusandae consequuntur expedita et cum\\nreprehenderit molestiae ut ut quas totam\\nnostrum rerum est autem sunt rem eveniet architecto"
'
}}
Networking Filters
The following networking-related filters are supported:
is_ip
2017.7.0
Return if a string is a valid IP Address.
{{ '192.168.0.1' | is_ip }}
Additionally accepts the following options:
- global
- link-local
- loopback
- multicast
- private
- public
- reserved
- site-local
- unspecified
Example - test if a string is a valid loopback IP address.
{{ '192.168.0.1' | is_ip(options='loopback') }}
is_ipv4
2017.7.0
Returns if a string is a valid IPv4 address. Supports the same
options as is_ip
.
{{ '192.168.0.1' | is_ipv4 }}
is_ipv6
2017.7.0
Returns if a string is a valid IPv6 address. Supports the same
options as is_ip
.
{{ 'fe80::' | is_ipv6 }}
ipaddr
2017.7.0
From a list, returns only valid IP entries. Supports the same options
as is_ip
. The list can contains also IP
interfaces/networks.
Example:
{{ ['192.168.0.1', 'foo', 'bar', 'fe80::'] | ipaddr }}
Returns:
'192.168.0.1', 'fe80::'] [
ipv4
2017.7.0
From a list, returns only valid IPv4 entries. Supports the same
options as is_ip
. The list can contains also IP
interfaces/networks.
Example:
{{ ['192.168.0.1', 'foo', 'bar', 'fe80::'] | ipv4 }}
Returns:
'192.168.0.1'] [
ipv6
2017.7.0
From a list, returns only valid IPv6 entries. Supports the same
options as is_ip
. The list can contains also IP
interfaces/networks.
Example:
{{ ['192.168.0.1', 'foo', 'bar', 'fe80::'] | ipv6 }}
Returns:
'fe80::'] [
network_hosts
2017.7.0
Return the list of hosts within a networks. This utility works for both IPv4 and IPv6.
Note
When running this command with a large IPv6 network, the command will take a long time to gather all of the hosts.
Example:
{{ '192.168.0.1/30' | network_hosts }}
Returns:
'192.168.0.1', '192.168.0.2'] [
network_size
2017.7.0
Return the size of the network. This utility works for both IPv4 and IPv6.
Example:
{{ '192.168.0.1/8' | network_size }}
Returns:
16777216
gen_mac
2017.7.0
Generates a MAC address with the defined OUI prefix.
Common prefixes:
00:16:3E
-- Xen00:18:51
-- OpenVZ00:50:56
-- VMware (manually generated)52:54:00
-- QEMU/KVMAC:DE:48
-- PRIVATE
Example:
{{ '00:50' | gen_mac }}
Returns:
00:50:71:52:1C
mac_str_to_bytes
2017.7.0
Converts a string representing a valid MAC address to bytes.
Example:
{{ '00:11:22:33:44:55' | mac_str_to_bytes }}
Note
This option may have adverse effects when using the default renderer,
yaml_jinja
. This is due to the fact that YAML requires
proper handling in regard to special characters. Please see the section
on YAML ASCII support <yaml_plain_ascii>
in the
YAML Idiosyncracies <yaml-idiosyncrasies>
documentation for more information.
dns_check
2017.7.0
Return the ip resolved by dns, but do not exit on failure, only raise an exception. Obeys system preference for IPv4/6 address resolution.
Example:
{{ 'www.google.com' | dns_check(port=443) }}
Returns:
'172.217.3.196'
File filters
is_text_file
2017.7.0
Return if a file is text.
Uses heuristics to guess whether the given file is text or binary, by reading a single block of bytes from the file. If more than 30% of the chars in the block are non-text, or there are NUL ('x00') bytes in the block, assume this is a binary file.
Example:
{{ '/etc/salt/master' | is_text_file }}
Returns:
True
is_binary_file
2017.7.0
Return if a file is binary.
Detects if the file is a binary, returns bool. Returns True if the file is a bin, False if the file is not and None if the file is not available.
Example:
{{ '/etc/salt/master' | is_binary_file }}
Returns:
False
is_empty_file
2017.7.0
Return if a file is empty.
Example:
{{ '/etc/salt/master' | is_empty_file }}
Returns:
False
file_hashsum
2017.7.0
Return the hashsum of a file.
Example:
{{ '/etc/salt/master' | file_hashsum }}
Returns:
02d4ef135514934759634f10079653252c7ad594ea97bd385480c532bca0fdda
list_files
2017.7.0
Return a recursive list of files under a specific path.
Example:
{{ '/etc/salt/' | list_files | join('\n') }}
Returns:
/etc/salt/master
/etc/salt/proxy
/etc/salt/minion
/etc/salt/pillar/top.sls
/etc/salt/pillar/device1.sls
path_join
2017.7.0
Joins absolute paths.
Example:
{{ '/etc/salt/' | path_join('pillar', 'device1.sls') }}
Returns:
/etc/salt/pillar/device1.sls
which
2017.7.0
Python clone of /usr/bin/which.
Example:
{{ 'salt-master' | which }}
Returns:
/usr/local/salt/virtualenv/bin/salt-master
Tests
Saltstack extends builtin tests with these custom tests:
equalto
Tests the equality between two values.
Can be used in an if
statement directly:
{% if 1 is equalto(1) %}
< statements >
{% endif %}
If clause evaluates to True
or with the selectattr
filter:
{{ [{'value': 1}, {'value': 2} , {'value': 3}] | selectattr('value', 'equalto', 3) | list }}
Returns:
'value': 3}] [{
match
Tests that a string matches the regex passed as an argument.
Can be used in a if
statement directly:
{% if 'a' is match('[a-b]') %}
< statements >
{% endif %}
If clause evaluates to True
or with the selectattr
filter:
{{ [{'value': 'a'}, {'value': 'b'}, {'value': 'c'}] | selectattr('value', 'match', '[b-e]') | list }}
Returns:
'value': 'b'}, {'value': 'c'}] [{
Test supports additional optional arguments: ignorecase
,
multiline
Escape filters
regex_escape
2017.7.0
Allows escaping of strings so they can be interpreted literally by another function.
Example:
regex_escape = {{ 'https://example.com?foo=bar%20baz' | regex_escape }}
will be rendered as:
regex_escape = https\:\/\/example\.com\?foo\=bar\%20baz
Set Theory Filters
unique
2017.7.0
Performs set math using Jinja filters.
Example:
unique = {{ ['foo', 'foo', 'bar'] | unique }}
will be rendered as:
unique = ['foo', 'bar']
Jinja in Files
Jinja can be used in the same way in managed files:
# redis.sls
/etc/redis/redis.conf:
file.managed:
- source: salt://redis.conf
- template: jinja
- context:
bind: 127.0.0.1
# lib.sls
{% set port = 6379 %}
# redis.conf
{% from 'lib.sls' import port with context %}
port {{ port }}
bind {{ bind }}
As an example, configuration was pulled from the file context and from an external template file.
Note
Macros and variables can be shared across templates. They should not be starting with one or more underscores, and should be managed by one of the following tags: macro, set, load_yaml, load_json, import_yaml and import_json.
Escaping Jinja
Occasionally, it may be necessary to escape Jinja syntax. There are two ways to do this in Jinja. One is escaping individual variables or strings and the other is to escape entire blocks.
To escape a string commonly used in Jinja syntax such as
{{
, you can use the following syntax:
{{ '{{' }}
For larger blocks that contain Jinja syntax that needs to be escaped, you can use raw blocks:
{% raw %}
some text that contains jinja characters that need to be escaped
{% endraw %}
See the Escaping section of Jinja's documentation to learn more.
A real-word example of needing to use raw tags to escape a larger
block of code is when using file.managed
with the
contents_pillar
option to manage files that contain
something like consul-template, which shares a syntax subset with Jinja.
Raw blocks are necessary here because the Jinja in the pillar would be
rendered before the file.managed is ever called, so the Jinja syntax
must be escaped:
{% raw %}
- contents_pillar: |
job "example-job" {
<snipped>
task "example" {
driver = "docker"
config {
image = "docker-registry.service.consul:5000/example-job:{{key "nomad/jobs/example-job/version"}}"
<snipped>
{% endraw %}
Calling Salt Functions
The Jinja renderer provides a shorthand lookup syntax for the
salt
dictionary of execution function <Execution Function>
.
2014.7.0
# The following two function calls are equivalent.
{{ salt['cmd.run']('whoami') }}
{{ salt.cmd.run('whoami') }}
Debugging
The show_full_context
function can be used to output all
variables present in the current Jinja context.
2014.7.0
Context is: {{ show_full_context()|yaml(False) }}
Logs
2017.7.0
Yes, in Salt, one is able to debug a complex Jinja template using the logs. For example, making the call:
{%- do salt.log.error('testing jinja logging') -%}
Will insert the following message in the minion logs:
2017-02-01 01:24:40,728 [salt.module.logmod][ERROR ][3779] testing jinja logging
Python Methods
A powerful feature of jinja that is only hinted at in the official jinja documentation is that you can use the native python methods of the variable type. Here is the python documentation for string methods.
{% set hostname,domain = grains.id.partition('.')[::2] %}{{ hostname }}
{% set strings = grains.id.split('-') %}{{ strings[0] }}
Custom Execution Modules
Custom execution modules can be used to supplement or replace complex Jinja. Many tasks that require complex looping and logic are trivial when using Python in a Salt execution module. Salt execution modules are easy to write and distribute to Salt minions.
Functions in custom execution modules are available in the Salt execution module dictionary just like the built-in execution modules:
{{ salt['my_custom_module.my_custom_function']() }}
How to Convert Jinja Logic to an Execution Module <tutorial-jinja_to_execution-module>
Writing Execution Modules <writing-execution-modules>
Custom Jinja filters
Given that all execution modules are available in the Jinja template, one can easily define a custom module as in the previous paragraph and use it as a Jinja filter. However, please note that it will not be accessible through the pipe.
For example, instead of:
{{ my_variable | my_jinja_filter }}
The user will need to define my_jinja_filter
function
under an extension module, say my_filters
and use as:
{{ salt.my_filters.my_jinja_filter(my_variable) }}
The greatest benefit is that you are able to access thousands of existing functions, e.g.:
get the DNS AAAA records for a specific address using the
dnsutil <salt.modules.dnsutil>
:{{ salt.dnsutil.AAAA('www.google.com') }}
retrieve a specific field value from a
Redis <salt.modules.modredis>
hash:{{ salt.redis.hget('foo_hash', 'bar_field') }}
get the routes to
0.0.0.0/0
using theNAPALM route <salt.modules.napalm_route>
:{{ salt.route.show('0.0.0.0/0') }}