primeiro hangout da Clojurers https://t.me/clojurebrasil

core.clj

;; Deve estar em `src/clojurebrasil/core.clj`
;; Execute `lein repl` na pasta do project.clj e tudo deve funcionar

(ns clojurebrasil.core
  (:require [datomic.api :as d]
            [cheshire.core :as cheshire]
            [io.pedestal.http :as http]))

(def schema
  [{:db/doc         "id do usuário"
    :db/ident       :user/id
    :db/index       true
    :db/valueType   :db.type/uuid
    :db/cardinality :db.cardinality/one
    :db/unique      :db.unique/identity
    :db/id          (d/tempid :db.part/db)}
   {:db/doc         "nome do usuário"
    :db/ident       :user/name
    :db/index       true
    :db/fulltext    true
    :db/valueType   :db.type/string
    :db/cardinality :db.cardinality/one
    :db/id          (d/tempid :db.part/db)}
   {:db/doc         "todos do usuário"
    :db/ident       :user/todos
    :db/index       true
    :db/valueType   :db.type/ref
    :db/cardinality :db.cardinality/many
    :db/id          (d/tempid :db.part/db)}
   {:db/doc         "o todo esta completo?"
    :db/ident       :todo/done?
    :db/index       true
    :db/valueType   :db.type/boolean
    :db/cardinality :db.cardinality/one
    :db/id          (d/tempid :db.part/db)}
   {:db/doc         "texto do todo"
    :db/ident       :todo/text
    :db/index       true
    :db/fulltext    true
    :db/valueType   :db.type/string
    :db/cardinality :db.cardinality/one
    :db/id          (d/tempid :db.part/db)}
   {:db/doc         "headers"
    :db/ident       :audit/headers
    :db/index       true
    :db/fulltext    true
    :db/valueType   :db.type/string
    :db/cardinality :db.cardinality/one
    :db/id          (d/tempid :db.part/db)}
   {:db/doc         "texto do todo"
    :db/ident       :todo/id
    :db/index       true
    :db/valueType   :db.type/uuid
    :db/unique      :db.unique/identity
    :db/cardinality :db.cardinality/one
    :db/id          (d/tempid :db.part/db)}])

(def db-uri "datomic:mem://clojurebrasil")

(defonce conn (atom nil))

(defn init-db! []
  (d/delete-database db-uri)
  (d/create-database db-uri)
  (reset! conn (d/connect db-uri))
  @(d/transact @conn schema)))

(defonce http-srv (atom nil))

(defn db-get-users
  [db search pattern]
  (d/q '[:find [(pull ?e pattern) ...]
         :in $ pattern ?search
         :where
         [?e :user/name ?n]
         [(clojure.string/includes? ?n ?search)]]
       db pattern (or search "")))


(defn get-users
  [{{:keys [search]} :query-params}]
  (prn search)
  (let [db (d/db @conn)
        users (db-get-users db search [:user/name :user/id])]
    {:body   users
     :status 200}))

(defn db-create-user
  [tempid name]
  [{:db/id     tempid
    :user/id   (d/squuid)
    :user/name name}])


(defn create-user
  [{:keys [body headers]}]
  (let [{:keys [name]} (cheshire/parse-string (slurp body) true)
        temp (d/tempid :db.part/user)
        tx-data (concat (db-create-user temp name)
                        [{:db/id         (d/tempid :db.part/tx)
                          :audit/headers (str headers)}])
        {:keys [db-after tempids]} @(d/transact @conn tx-data)
        id (d/resolve-tempid db-after tempids temp)]
    {:body   (d/pull db-after [:user/name :user/id] id)
     :status 200}))

(def ->json
  {:name  ::->json
   :leave (fn [ctx] (update-in ctx [:response :body] cheshire/generate-string {:key-fn name}))})

(def routes
  #{["/user" :get [->json get-users] :route-name ::get-users]
    ["/user" :post [->json create-user] :route-name ::create-user]})

(def service
  {:env          :dev
   ::http/type   :jetty
   ::http/routes routes
   ::http/join?  false
   ::http/port   8080})


(defn -main
  "The entry-point for 'lein run-dev'"
  [& args]
  (->> service
       http/default-interceptors
       http/dev-interceptors
       http/create-server
       http/start
       (reset! http-srv)))

project.clj

(defproject clojurebrasil "0.1.0-SNAPSHOT"
  :dependencies [[org.clojure/clojure "1.9.0"]
                 [io.pedestal/pedestal.service "0.5.3"]
                 [io.pedestal/pedestal.jetty "0.5.3"]
                 [com.datomic/datomic-free "0.9.5656"]]
  :source-paths ["src"]
  :main clojurebrasil.core)