datomic-schema

Simplified writing of Datomic schemas.

Installation

Add [ivarref/datomic-schema "0.1.6"] to your dependency vector.

Syntax

The syntax is

#d/schema[[attribute-name cardinality? type toggles* docstring?]*]

attribute-name = The name of your attribute
cardinality    = :one or :many. Defaults to :one
type           = A type from the list below
toggles        = Zero or more toggles
docstring      = An optional documentation string

type           = :bigdec  |
                 :bigint  |
                 :boolean |
                 :bytes   |
                 :double  |
                 :float   |
                 :instant |
                 :keyword |
                 :long    |
                 :ref     |
                 :string  |
                 :uri     |
                 :uuid

toggles        = :component  |
                 :fulltext   |
                 :id         | ; alias for :identity
                 :identity   |
                 :index      |
                 :no-history |
                 :unique

All arguments except docstring must be Clojure keywords.

Enums are also supported: #d/schema [[attribute-name :enum]]

Example usage from REPL

(require 'datomic-schema.core)

#d/schema [[:entity/attr :one :string "Documentation"]]
=>
[{:db/id #db/id[:db.part/db -1000001],
  :db/ident :entity/attr,
  :db/valueType :db.type/string,
  :db/cardinality :db.cardinality/one,
  :db.install/_attribute :db.part/db,
  :db/doc "Documentation"}]

#d/schema [[:entity/attr :many :long :unique]]
=>
[{:db/id #db/id[:db.part/db -1000002],
  :db/ident :entity/attr,
  :db/valueType :db.type/long,
  :db/cardinality :db.cardinality/many,
  :db.install/_attribute :db.part/db,
  :db/unique :db.unique/value}]
  
#d/schema [[:entity/attr :enum]]
=>
[{:db/ident :entity/attr}]

and so forth.

Example usage with conformity

In order to use this library with conformity, you will need to require the namespace so that the reader literal is loaded before conformity runs.

Add the following file to resources/:

;; resources/something.edn
{:my-project/something-schema
 {:txes [#d/schema[[:something/title :one :string]
                   [:something/author :one :uuid]]]}}

Then in your code:

(ns my-project.something
  (:require [datomic-schema.core] ; namespace needs to be required so that reader literal is loaded
            [io.rkn.conformity :as c]
            [datomic.api :as d]))

(def uri "datomic:mem://my-project")
(d/create-database uri)
(def conn (d/connect uri))

(def norms-map (c/read-resource "something.edn"))

(println (str "Has attribute? " (c/has-attribute? (d/db conn) :something/title)))
(c/ensure-conforms conn norms-map [:my-project/something-schema])
(println (str "Has attribute? " (c/has-attribute? (d/db conn) :something/title)))

Notes

This project is derived from cognitect-labs/vase.

License

Copyright © 2015-2017 Cognitect, Inc. All rights reserved.

Copyright © 2018 Ivar Refsdal.

Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.