---json
{
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        { "path": ":docs:conf:variable" }
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---
====== Attribute ======


===== About =====
''attributes'' are [[:docs:resource:metadata|metadata]] key pair values that are used:
  * to configure the behavior of tabulify (known as parameter)
  * or as [[template|template variable]] 





===== Type =====
There is 3 kinds of attributes:
  * [[parameter|parameters]]: fixed value that you can set
  * ''literal'': literal value retrieved from a [[:docs:system:system|system]] (Example: creation date, ...)
  * ''computed'': value derived through computation (Example: [[:docs:resource:count|count]], digest, ...)


===== Value =====

The value of an attribute may be:
  * [[:docs:tabul:vault:encrypt|encrypted]]
  * an [[docs:conf:global_env|environment variable]]
  * or a literal (ie not derived, the raw value)
===== Key Casing =====

==== Case Input: Independent sensitivity ====

Attribute names are ''case independent'' meaning that all these names are equivalent
  * ''UserCount / userCount'' - Camel Case
  * ''user_count / USER_COUNT'' - Snake Case
  * ''user-count / USER-COUNT'' - Kebab/Hyphen Case

But the following are not:
  * ''dataset'' and ''dataSet''
  * ''uSerCount'' and ''userCount'' 

Why ? We parse the attribute name into words using as separators: 
  * uppercase
  * spaces, 
  * underscores
  * and any non alphanumeric character

Therefore:
  * ''dataset'' is 1 word: ''dataset''
  * ''dataSet'''is 2 words:  ''data'' and ''set''
  * ''userCount'' is 2 words: ''user'' and ''count''
  * ''uSerCount'' is 3 words: ''u'', ''ser'' and ''count'' 



==== Casing output ====

Casing is a matter of:
  * visual taste
  * convention
  * specification and [[:docs:flow:target|target system]]  (ie SQL does not allow a `-` minus in a name if not quoted)


We try to follow the following conventions when printing or serializing:

  * [[:docs:op:print|Print]] Value: UPPER_SNAKE_CASE (mostly to show that they can be set via [[:docs:conf:os|os environment variable]]
  * [[:docs:op:print|Print]] Header / [[:docs:resource:column|Column]] Name: ''lower_snake_case'' because 
    * lowercase is the standard state on a keyboard (one key press won, is one key press less)
    * and we don't like shouting
  * [[:docs:common:yaml|Yaml]] file: kebab-case (ie hyphen)