Clojure(Script) tools for clojure.spec. Like Schema-tools but for spec.
Status: Alpha (as spec is still alpha too).
Blogs:
Requires Java 1.8 & Clojure 1.9.0-alpha17
and/or ClojureScript 1.9.562
.
To support spec metadata and extensions like dynamic conforming, Spec-tools introduces extendable Spec Records, Spec
s. They wrap specs and act like specs or 1-arity functions. Specs are created with spec-tools.core/spec
macro of with the underlying spec-tools.core/create-spec
function.
The following Spec keys having a special meaning:
Key | Description |
---|---|
:spec |
The wrapped spec (predicate). |
:form |
The wrapped spec form. |
:type |
Type hint of the Spec, mostly auto-resolved. Used in runtime conformation. |
:name |
Name of the spec. Maps to title in JSON Schema. |
:description |
Description of the spec. Maps to description in JSON Schema. |
:gen |
Generator function for the Spec (set via s/with-gen ) |
:keys |
Set of map keys that the spec defines. Extracted from s/keys Specs. |
:reason |
Value is added to s/explain-data problems under key :reason |
:json-schema/... |
Extra data that is merged with unqualifed keys into json-schema |
The following are all equivalent:
(require '[spec-tools.core :as st])
;; using type inference
(st/spec integer?)
;; with explicit type
(st/spec integer? {:type :long})
;; map form
(st/spec {:spec integer?})
(st/spec {:spec integer?, :type :long})
;; function
(st/create-spec
{:spec integer?
:form `integer?
:type :long})
;; function, with type and form inference
(st/create-spec
{:spec integer?})
;; ... resulting in:
; #Spec{:type :long,
; :form clojure.core/integer?}
(require '[clojure.spec.alpha :as s])
(def my-integer? (st/spec integer?))
my-integer?
; #Spec{:type :long
; :form clojure.core/integer?}
(my-integer? 1)
; true
(s/valid? my-integer? 1)
; true
(assoc my-integer? :description "It's a int")
; #Spec{:type :long
; :form clojure.core/integer?
; :description "It's a int"}
(eval (s/form (st/spec integer? {:description "It's a int"})))
; #Spec{:type :long
; :form clojure.core/integer?
; :description "It's a int"}
For most core predicates, :type
can be resolved automatically using the spec-tools.type/resolve-type
multimethod.
For most core predicates, :form
can be resolved automatically using the spec-tools.form/resolve-form
multimethod.
Most clojure.core
predicates have a predefined Spec Record instance in spec-tools.spec
.
(require '[spec-tools.spec :as spec])
spec/boolean?
; #Spec{:type :boolean
; :form clojure.core/boolean?}
(spec/boolean? true)
; true
(s/valid? spec/boolean? false)
; true
(assoc spec/boolean? :description "it's an bool")
; #Spec{:type :boolean
; :form clojure.core/boolean?
; :description "It's a bool"}
Can be added to a Spec via the key :reason
(s/explain (st/spec pos-int? {:reason "positive"}) -1)
; val: -1 fails predicate: pos-int?, positive
(s/explain-data (st/spec pos-int? {:reason "positive"}) -1)
; #:clojure.spec.alpha{:problems [{:path [], :pred pos-int?, :val -1, :via [], :in [], :reason "positive"}]}
Spec-tools loans from the awesome Schema by separating specs (what) from conformers (how). Spec Record has a dynamical conformer, which can be instructed at runtime to use a suitable conforming function for that spec. This enables same Specs to conform differently in different runtime conditions, e.g. when reading data from JSON vs Transit.
Spec Record conform is by default a no-op. Binding a dynamic var spec-tools.core/*conforming*
with a function of spec => spec-conformer
will cause the Spec to be conformed with the selected spec-conformer. spec-tools.core
has helper functions for setting the binding: explain
, explain-data
, conform
and conform!
.
Spec-conformers are arity2 functions taking the Spec Records and the value and should return either conformed value or :clojure.spec.alpha/invalid
.
A common way to do dynamic conforming is to select conformer based on the spec's :type
. By default, the following types are supported (and mostly, auto-resolved): :long
, :double
, :boolean
, :string
, :keyword
, :symbol
, :uuid
, :uri
, :bigdec
, :date
, :ratio
, :map
, :set
and :vector
.
The following type-based conforming are found in spec-tools.core
:
Name | Description |
---|---|
string-conforming |
Conforms all specs from strings (things like :query , :header & :path -parameters). |
json-conforming |
JSON Conforming (numbers and booleans not conformed). |
strip-extra-keys-conforming |
Strips out extra keys of s/keys Specs. |
fail-on-extra-keys-conforming |
Fails if s/keys Specs have extra keys. |
nil |
No extra conforming (EDN & Transit). |
(s/def ::age (s/and spec/integer? #(> % 18)))
;; no conforming
(s/conform ::age "20")
(st/conform ::age "20")
(st/conform ::age "20" nil)
; ::s/invalid
;; json-conforming
(st/conform ::age "20" st/json-conforming)
; ::s/invalid
;; string-conforming
(st/conform ::age "20" st/string-conforming)
; 20
(s/def ::name string?)
(s/def ::birthdate spec/inst?)
(s/def ::languages
(s/coll-of
(s/and spec/keyword? #{:clj :cljs})
:into {}))
(s/def ::user
(s/keys
:req-un [::name ::languages ::age]
:opt-un [::birthdate]))
(def data
{:name "Ilona"
:age "48"
:languages ["clj" "cljs"]
:birthdate "1968-01-02T15:04:05Z"})
;; no conforming
(st/conform ::user data)
; ::s/invalid
;; json-conforming doesn't conform numbers
(st/conform ::user data st/json-conforming)
; ::s/invalid
;; string-conforming for the rescue
(st/conform ::user data st/string-conforming)
; {:name "Ilona"
; :age 48
; :languages #{:clj :cljs}
; :birthdate #inst"1968-01-02T15:04:05.000-00:00"}
To strip out extra keys from a keyset:
(s/def ::street string?)
(s/def ::address (st/spec (s/keys :req-un [::street])))
(s/def ::user (st/spec (s/keys :req-un [::name ::street])))
(def inkeri
{:name "Inkeri"
:age 102
:address {:street "Satamakatu"
:city "Tampere"}})
(st/conform
::user
inkeri
st/strip-extra-keys-conforming)
; {:name "Inkeri"
; :address {:street "Satamakatu"}}
Inspired by the Schema-tools, there are also a select-spec
to achieve the same:
(st/select-spec ::user inkeri)
; {:name "Inkeri"
; :address {:street "Satamakatu"}}
(require '[clojure.string :as str])
(def my-string-conforming
(st/type-conforming
(assoc
conform/string-type-conforming
:keyword
(fn [_ value]
(-> value
str/upper-case
str/reverse
keyword))))
(st/conform spec/keyword? "kikka")
; ::s/invalid
(st/conform spec/keyword? "kikka" st/string-conforming)
; :kikka
(st/conform spec/keyword? "kikka" my-string-conforming)
; :AKKIK
Type-based conforming mappings are defined as data, so they are easy to combine and extend:
(require '[spec-tools.conform :as conform])
(def strict-json-conforming
(st/type-conforming
(merge
conform/json-type-conforming
conform/strip-extra-keys-type-conforming)))
(require '[spec-tools.data-spec :as ds])
Data Specs offers an alternative, Schema-like data-driven syntax to define simple nested collection specs. Rules:
- Just data, no macros
- Can be transformed into vanilla specs with valid forms (via form inference)
- Vectors and Sets are homogeneous, and must contains exactly one spec
- Maps have either a single spec key (homogeneous keys) or any number keyword keys.
- With homogeneous keys, keys are also conformed
- Map (keyword) keys
- can be qualified or non-qualified (a qualified name will be generated for it)
- are required by default
- can be wrapped into
ds/opt
ords/req
for making them optional or required.
- Map values
- can be functions, specs, qualified spec names or nested collections.
- wrapping value into
ds/maybe
makes its/nillable
NOTE: to avoid macros, current implementation uses the undocumented functional core of clojure.spec.alpha
: every-impl
, tuple-impl
, map-spec-impl
& nilable-impl
.
(s/def ::age spec/pos-int?)
;; a data-spec
(def person
{::id integer?
::age ::age
:boss boolean?
(ds/req :name) string?
(ds/opt :description) string?
:languages #{keyword?}
:orders [{:id int?
:description string?}]
:address (ds/maybe
{:street string?
:zip string?})})
;; it's just data.
(def new-person
(dissoc person ::id))
- to turn a data-spec into a Spec, call
ds/spec
on it, providing a qualified keyword describing the root spec name - used to generate unique names for sub-specs that will be registered.
;; transform into specs
(def person-spec
(ds/spec ::person person))
(def new-person-spec
(ds/spec ::person new-person))
- the following specs are now registered:
(keys (st/registry #"user.*"))
; (:user/id
; :user/age
; :user$person/boss
; :user$person/name
; :user$person/description
; :user$person/languages
; :user$person/orders
; :user$person$orders/description
; :user$person$orders/id
; :user$person/address
; :user$person$address/street
; :user$person$address/zip)
- and now we have specs:
(s/valid?
new-person-spec
{::age 63
:boss true
:name "Liisa"
:languages #{:clj :cljs}
:orders [{:id 1, :description "cola"}
{:id 2, :description "kebab"}]
:description "Liisa is a valid boss"
:address {:street "Amurinkatu 2"
:zip "33210"}})
; true
- all generated specs are wrapped into Specs Records so dynamic conforming works out of the box:
(st/conform!
new-person-spec
{::age "63"
:boss "true"
:name "Liisa"
:languages ["clj" "cljs"]
:orders [{:id "1", :description "cola"}
{:id "2", :description "kebab"}]
:description "Liisa is a valid boss"
:address nil}
st/string-conforming)
; {::age 63
; :boss true
; :name "Liisa"
; :languages #{:clj :cljs}
; :orders [{:id 1, :description "cola"}
; {:id 2, :description "kebab"}]
; :description "Liisa is a valid boss"
; :address nil}
A tool to walk over and transform specs using the Visitor-pattern. There is a example visitor to collect all the registered specs linked to a spec. The JSON Schema -generation uses this.
(require '[spec-tools.visitor :as visitor])
;; visitor to collect all registered specs
(let [specs (atom {})]
(visitor/visit
person-spec
(fn [_ spec _]
(if-let [s (s/get-spec spec)]
(swap! specs assoc spec (s/form s))
@specs))))
; {:user/id (spec-tools.core/spec
; {:spec clojure.core/integer?
; :type :long})
; :user/age (spec-tools.core/spec
; {:spec clojure.core/pos-int?
; :type :long})
; :user$person/boss (spec-tools.core/spec
; {:spec clojure.core/boolean?
; :type :boolean})
; :user$person/name (spec-tools.core/spec
; {:spec clojure.core/string?
; :type :string})
; :user$person/languages (spec-tools.core/spec
; {:spec (clojure.spec.alpha/coll-of
; (spec-tools.core/spec
; {:spec clojure.core/keyword?
; :type :keyword})
; :into #{})
; :type :set})
; :user$person$orders/id (spec-tools.core/spec
; {:spec clojure.core/int?
; :type :long})
; :user$person$orders/description (spec-tools.core/spec
; {:spec clojure.core/string?
; :type :string})
; :user$person/orders (spec-tools.core/spec
; {:spec (clojure.spec.alpha/coll-of
; (spec-tools.core/spec
; {:spec (clojure.spec.alpha/keys
; :req-un [:user$person$orders/id :user$person$orders/description])
; :type :map
; :keys #{:id :description}})
; :into [])
; :type :vector})
; :user$person$address/street (spec-tools.core/spec
; {:spec clojure.core/string?
; :type :string})
; :user$person$address/zip (spec-tools.core/spec
; {:spec clojure.core/string?
; :type :string})
; :user$person/address (spec-tools.core/spec
; {:spec (clojure.spec.alpha/nilable
; (spec-tools.core/spec
; {:spec (clojure.spec.alpha/keys
; :req-un [:user$person$address/street :user$person$address/zip])
; :type :map
; :keys #{:street :zip}}))
; :type nil})
; :user$person/description (spec-tools.core/spec
; {:spec clojure.core/string?
; :type :string})}
NOTE: due to CLJ-2152, s/&
& s/keys*
can't be visited.
Generating JSON Schemas from arbitrary specs (and Spec Records).
(require '[spec-tools.json-schema :as jsc])
(jsc/transform person-spec)
; {:type "object"
; :properties {"user/id" {:type "integer"}
; "user/age" {:type "integer", :format "int64", :minimum 1}
; "boss" {:type "boolean"}
; "name" {:type "string"}
; "languages" {:type "array", :items {:type "string"}, :uniqueItems true}
; "orders" {:type "array"
; :items {:type "object"
; :properties {"id" {:type "integer", :format "int64"}
; "description" {:type "string"}}
; :required ["id" "description"]}}
; "address" {:oneOf [{:type "object"
; :properties {"street" {:type "string"}
; "zip" {:type "string"}}
; :required ["street" "zip"]}
; {:type "null"}]}
; "description" {:type "string"}}
; :required ["user/id" "user/age" "boss" "name" "languages" "orders" "address"]}
Extra data from Spec records is used to populate the data:
(jsc/transform
(st/spec
{:spec integer?
:name "integer"
:description "it's an int"
:json-schema/default 42}))
; {:type "integer"
; :title "integer"
; :description "it's an int"
; :default 42}
Related:
Copyright © 2016-2017 Metosin Oy
Distributed under the Eclipse Public License, the same as Clojure.