duct.core — duct/core 0.7.0

Core functions required by a Duct application.

add-shutdown-hook clj

(add-shutdown-hook key func)

Set a function to be executed when the current process shuts down. The key argument should be unique, and is used in remove-shutdown-hook.

await-daemons clj

(await-daemons system)

If the supplied system has keys deriving from :duct/daemon, block the current thread indefinitely and add a shutdown hook to halt the system.

build-config clj

(build-config config)

(build-config config profiles)

Build an Integrant configuration from a configuration of modules. A collection of profile keys may optionally be supplied that govern which profiles to use (see profile-keys). Omitting the profiles or using the :all keyword in their stead will result in all keys being used.

exec-config clj

(exec-config config)

(exec-config config profiles)

(exec-config config profiles keys)

Build, prep and initiate a configuration of modules, then block the thread (see await-daemons). By default it only runs profiles derived from :duct.profile/prod and keys derived from :duct/daemon.

This function is designed to be called from -main when standalone operation is required.

fold-modules clj

(fold-modules system)

Fold a system map of modules into an Integrant configuration. A module is a pure function that transforms a configuration map. The modules are traversed in dependency order and applied to iteratively to a blank map in order to build the final configuration.

load-hierarchy clj

(load-hierarchy)

Search the base classpath for files named duct_hierarchy.edn, and use them to extend the global derive hierarchy. This allows a hierarchy to be constructed without needing to load every namespace.

The duct_hierarchy.edn file should be an edn map that maps child keywords to vectors of parents. For example:

{:example/child [:example/father :example/mother]}

This is equivalent to writing:

(derive :example/child :example/father)
(derive :example/child :example/mother)

This function should be called once when the application is started.

merge-configs clj

(merge-configs & configs)

Intelligently merge multiple configurations. Uses meta-merge and will merge configurations in order from left to right. Generic top-level keys are merged into more specific descendants, if the descendants exist.

parse-keys clj

(parse-keys args)

Parse config keys from a sequence of command line arguments.

prep-config clj

(prep-config config)

(prep-config config profiles)

Load, build and prep a configuration of modules into an Integrant configuration that's ready to be initiated. This function loads in relevant namespaces based on key names, so is side-effectful (though idempotent).

profile-keys clj

(profile-keys config profiles)

Return a collection of keys for a configuration that excludes any profile not present in the supplied colleciton of profiles. Profiles may be specified as namespaced keywords, or as un-namespaced keywords, in which case only the name will matched (e.g. :dev will match :duct.profile/dev). If the :all keyword is supplied instead of a profile collection, all keys are returned.

read-config clj

(read-config source)

(read-config source readers)

Read an edn configuration from a slurpable source. An optional map of data readers may be supplied. By default the following five readers are supported:

#duct/env : an environment variable, see duct.core.env/env

#duct/include : substitute for a configuration on the classpath

#duct/resource : a resource path string, see resource

#ig/ref : an Integrant reference to another key

#ig/refset : an Integrant reference to a set of keys

remove-shutdown-hook clj

(remove-shutdown-hook key)

Remove a shutdown hook identified by the specified key.

resource clj

(resource path)

Return an record that represents a resource on the classpath, compatible with clojure.java.io functions like reader, input-stream and as-url. When printed, the record returns a string tagged with #duct/resource. This makes it more useful than a bare URL object when printing a configuration. If the resource does not exist, nil is returned.

target-path clj

A path to place generated files in. Typically used by compilers. Can be set via the duct.target.path system property.