exoscale/yummy

YAML configuration for Clojure application

yummy: YAML configuration for Clojure application

Yummy allows reading in configuration from YAML files and provides optional facilities for:

• Environment based configuration
• Validation through clojure.spec

Yummy only provides YAML parsing, no generation facilities are present.

Using

Auto determined configuration file paths:

(spec/def ::config (spec/keys :req-un [::http ::logging ::database]))
(yummy.config/load-config {:program-name :mydaemon :spec ::config})

Yummy will look for a configuration-file path in the mydaemon.configuration system property or the MYDAEMON_CONFIGURATION environment variable.

A path can outright be given as well:

(spec/def ::config (spec/keys :req-un [::http ::logging ::database]))
(yummy.config/load-config {:path "/etc/mydaemon.yml" :spec ::config})

Alternately configuration can be loaded from a string:

(yummy.config/load-config-string "a: b" {})

Additional YAML Tags

To make integration as simple as possible, Yummy understands a number of custom tag parsers, namely:

• envdir: loads a map from a directory, treating file names as keys and content as values
• envvar: loads a value from the environment, optionally taking in defaults
• keyword: coerce a string to a keyword
• envfmt: produce a string from a format string and environment variables to pull in
• slurp: produce a string from the given file content
• uuid: produce a UUID from the given string

Example

a: !keyword b
b: !envvar HOME
c: !envvar [NOPE, hello]
d: !envdir /tmp/foo
e: !envfmt ["user=%s, home=%s", USER, HOME]
f: !slurp "/etc/hostname"
g: !uuid fc716a9b-fb1e-4ebd-b781-5ca13039aa55

Documentation

http://exoscale.github.io/yummy

Installation

    [[exoscale/yummy "0.2.6"]]

yummy's Issues

Bump outdated vulnerable deps?

Hey,
just wanted to ask if there are any plans to bump project's dependencies?
I am particularly concerned with org.yaml/snakeyaml that got 8 vulns including critical one.
Thanks

add !slurp

use case

kubernetes:
  bearer: !slurp "/var/secrets/.../token"

spec/conform instead of spec/assert?

At the moment, yummy performs spec/assert against the data. This is fine, but there is no chance to coerce the data as spec/conform does. Imagine I've got a date string in my yaml file or a regex pattern. There aren't such tags in yummy so far as well as I believe this is wrong way to extend yummy when we have spec.

My suggestion is to use spec/conform for validation and return the final value with coerced types. In my example, the string pattern might be adapted with ease:

(s/def ::pattern (s/conformer re-pattern))

If the result of conforming was ::invalid, we do explain-data and raise an ex-info manually.

Would you like me to submit a PR?