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Clojure for Tezos

• Endpoints are declared by adding an :entrypoint metadata at the function declaration, which could further extended to a defentrypoint macro.
• Due to the typed nature of Michelson, the code must be typed to properly be translated to code:
  • Type declarations should use the type function (or macro?) to declare types for namespace defined variables.
  • Extra type annotation could be done by using metadata.
  • Need for a type checker, which I don't know how to implement (I don't know to how to build a backend also, but don't tell anyone).
  • Michelson types need a correspondence for Clojure literals, while some are possible, conjunction and disjunction types are not available for Clojure.
• Some types have an extra challenge, like option and or, because Clojure doesn't have the proper idioms to deal with it, I should define a few patterns to describe how to interpret them, mainly option.
• To descrease the overhead for type inference, some literals are going to be used for natur

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FROM alpine

RUN apk add opam git musl-dev make m4 gcc bubblewrap bash coreutils pkgconfig openssl-libs-static openssl-dev
RUN opam init --disable-sandboxing
RUN opam install -y ocaml-base-compiler lambda-runtime dune

WORKDIR /app

COPY . .

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(executable
  (name server)
  (libraries ssl piaf yojson ppx_deriving_yojson.runtime)
  (preprocess (pps ppx_deriving_yojson)))

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let valid_cpf cpf =
  let aux size =
    let sum = ref 0 in
    for i = 0 to (size - 2) do
      sum := !sum + cpf.(i) * (size - i);
    done;
    !sum * 10 mod 11
  in
  (aux 10) == cpf.(9) && (aux 11) == cpf.(10)

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AWS_ACCESS_KEYID=
AWS_SECRET_KEY=
BUCKET=

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;;
;; Apesar de podermos fazer isso diretamente no `-main`, aqui
;; podemos separar a responsabilidade de interpretar as
;; opcoes e passar para os respectivos constructores dos
;; componentes.
;;
(defn system [& options]
  (let [{:keys [database-url port]} options]
    (component/system-map
     :database (new-database database-url)

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;;
;; Associa um valor `value` a um chave `key` no
;; primeiro argumento da funcao `f`.
;; 
;; Espera-se que `f` seja um handler que possa
;; ser usado com o Ring.
;;
(defn wrap-assoc [f key value]
  (fn [request] (f (assoc request key value))))

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;;
;; O web server pode seguir o mesmo protocolo
;; e principios que o banco de dados.
;;
(defrecord WebServer [port app]
  component/Lifecycle

  (start [component]
    (assoc component
      ::jetty

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;;
;; Todo o ciclo de vida do banco de dados
;; fica encapsulado em um componente.
;;
(defrecord Database [uri database connection]
  component/Lifecycle

  (start [component]
    (let [{:keys [conn db]} (mg/connect-via-uri uri)]
      (assoc component :database db

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(defrecord Database [uri database connection])

(defn create-database [uri]
  (let [{:keys [db conn]} (mg/connect-via-uri uri)]
    (map->Database {:uri uri
                    :database db
                    :connection conn})))