Accesing dictionary option not working as expected

[Aleksey Shirokih]

hi, i have such a template

{% set shard = printf("shard_%s", getenv("SHARD", 1)) %}
{% set config = getv("/shard_config") | parseYAML %}
{{ config.shard_1.machine }}
{% set shard_config = config.shard %}
{{ shard_config }}

And such key in consul

shard_1:
  machine: n1-standard-1
shard_2:
  machine: n1-standard-1

the problem is in last two lines of template, i'm expecting that will get data from {{ config.shard_1.machine }} but got empty string instead.

[Rene Kaufmann]

How are you setting the values in confd?

If i set it like this:

curl -X PUT http://172.17.0.2:8500/v1/kv/shard_config -d 'shard_1:                                                                                                                                                                              :(
  machine: n1-standard-1
shard_2:
  machine: n1-standard-1'

and use this template:

{% set shard = printf("shard_%s", getenv("SHARD", "1")) %}
{% set config = getv("/shard_config") | parseYAML %}
{{ config.shard_1.machine }}
{% set shard_config = config.shard_2.machine %}
{{ shard_config }}

i get this result:

n1-standard-1
n1-standard-1

[Aleksey Shirokih]

here {% set shard_config = config.shard_2.machine %} you are using hardcoded shard_2 but in template
i want to use shard variable that i get previously instead.

[Rene Kaufmann]

You can't access map keys like this config.shard because the map has no value "shard".
You would need a template filter in this case.

The simplest filter could be:

cat getMapValue.js

In[Param];

and the template:

{% set shard = printf("shard_%s", getenv("SHARD", "1")) %}
{% set config = getv("/shard_config") | parseYAML %}
{{ config.shard_1.machine }}
{% set shard_config = config | getMapValue:shard %}
{{ shard_config.machine }}

[Aleksey Shirokih]

oh. i see.
How that should be assembled? am i have to put getMapValue.js to templates directory ? have i load it in template ?

[Rene Kaufmann]

just create the file getMapValue.js wherever you want and set the filter directory in your config.

Here is my config
cat /etc/remco/config

log_level   = "debug"
log_format  = "text"
filter_dir  = "/etc/remco/filter.d"
include_dir = "/etc/rputemco/resource.d"

and /etc/remco/filter.d is my filter_dir with all my js filters.

[Rene Kaufmann]

 rkaufmann  rkaufmann  etc  remco  filter.d  %  ls
getMapValue.js  jsrev.js  toEnv.js
 rkaufmann  rkaufmann  etc  remco  filter.d  %  cat getMapValue.js
In[Param];

[Aleksey Shirokih]

thx. looks like it working!

But i have few questions :)
why it is called js ?
what should i read about writing new filters ?
seems links in pongo2 dead flosch/pongo2#180
and, don't you think that filter should be build in ?

[Rene Kaufmann]

why it is called js ?

because they are really javascript files :)
I use https://github.com/dop251/goja as the pure go javascript engine.
Take a look at https://heavyhorst.github.io/remco/template/template-filters/ to get a first impression.

don't you think that filter should be build in

Yes I will add it.

[Rene Kaufmann]

I added a filter to the latest master:

{{ getv("/some_yaml_config") | parseYAML | mapValue:"key" }}