add db queries

11 files changed, 266 insertions, 34 deletions

diff --git a/bin/dune b/bin/dune
index a186150..9c34236 100644
--- a/bin/dune
+++ b/bin/dune
@@ -5,17 +5,9 @@
    (:standard -cclib -static -cclib -no-pie))
  (libraries
    rinha
-
    piaf
    routes
    eio_main
-   caqti-driver-postgresql
    logs.fmt
    fmt.tty
-   logs.threaded
-   caqti-eio
-   caqti
-   ppx_rapper_eio)
-
- (preprocess
-  (pps ppx_rapper)))
+   logs.threaded))
diff --git a/bin/main.ml b/bin/main.ml
index 7e537a7..99cc0e0 100644
--- a/bin/main.ml
+++ b/bin/main.ml
@@ -4,9 +4,9 @@ open! StdLabels
 open Eio
 open Piaf
 
-let request_handler Server.{ request; _ } =
+let request_handler ~db_pool Server.{ request; _ } =
   match Rinha.Router.match_route request.meth request.target with
-  | Some handler -> handler request
+  | Some handler -> handler db_pool request
   | None -> Response.create `Not_found
 ;;
 
@@ -17,10 +17,16 @@ let () =
   @@ fun sw ->
   let config =
     let interface = Net.Ipaddr.V4.any in
-    let port = 3000 in
+    let port = 8080 in
     `Tcp (interface, port)
   in
   let config = Server.Config.create config in
-  let server = Server.create ~config request_handler in
+  let db_uri =
+    Uri.make ~scheme:"postgres" ~userinfo:"admin:123" ~host:"db" ~path:"rinha" ()
+  in
+  let db_pool =
+    Result.get_ok @@ Caqti_eio.connect_pool ~sw ~stdenv:(env :> Caqti_eio.stdenv) db_uri
+  in
+  let server = Server.create ~config (request_handler ~db_pool) in
   ignore @@ Server.Command.start ~sw env server
 ;;
diff --git a/lib/client.ml b/lib/client.ml
new file mode 100644
index 0000000..80a11b7
--- /dev/null
+++ b/lib/client.ml
@@ -0,0 +1,4 @@
+type t =
+  { id : int
+  ; mov_limit : int
+  }
diff --git a/lib/dune b/lib/dune
index 837c7b7..6c8a064 100644
--- a/lib/dune
+++ b/lib/dune
@@ -1,3 +1,5 @@
 (library
  (name rinha)
- (libraries piaf routes yojson))
+ (libraries piaf routes yojson caqti caqti-driver-postgresql caqti-eio ppx_rapper_eio)
+ (preprocess
+  (pps ppx_rapper)))
diff --git a/lib/operation.ml b/lib/operation.ml
new file mode 100644
index 0000000..1fb1dd5
--- /dev/null
+++ b/lib/operation.ml
@@ -0,0 +1,49 @@
+module TransactionType = struct
+  type t =
+    | Credit
+    | Debit
+
+  let t =
+    let encode = function
+      | Credit -> "credit"
+      | Debit -> "debit"
+    in
+    let decode = function
+      | "credit" -> Ok Credit
+      | "debit" -> Ok Debit
+      | _ -> Error "Invalid transaction type"
+    in
+    Caqti_type.(enum ~encode ~decode "transaction_type")
+  ;;
+end
+
+type t =
+  | Transaction of
+      { transaction_type : TransactionType.t
+      ; value : int
+      ; description : string
+      }
+  | Balance of { client_id : int }
+
+type transaction =
+  { id : int
+  ; client_id : int
+  ; value : int
+  ; transaction_type : TransactionType.t
+  ; description : string
+  ; created_at : Ptime.t
+  }
+
+let decoder =
+  let open Utils.Decoder in
+  let open Syntax in
+  let transaction_type_decoder =
+    literal "c" *> return TransactionType.Credit
+    <|> literal "d" *> return TransactionType.Debit
+  in
+  (fun value transaction_type description ->
+    Transaction { value; description; transaction_type })
+  <$> ("valor" <: int)
+  <*> ("tipo" <: transaction_type_decoder)
+  <*> ("descricao" <: string)
+;;
diff --git a/lib/query.ml b/lib/query.ml
new file mode 100644
index 0000000..0fb6f7e
--- /dev/null
+++ b/lib/query.ml
@@ -0,0 +1,37 @@
+type pool = ((module Rapper_helper.CONNECTION), Caqti_error.t) Caqti_eio.Pool.t
+
+let transaction_query =
+  [%rapper
+    execute
+      {sql|
+        INSERT INTO transactions (client_id, value, type, description)
+        VALUES (%int{client_id}, %int{value}, %Operation.TransactionType{transaction_type}, %string{description})
+      |sql}]
+;;
+
+let client_query =
+  let open Client in
+  [%rapper
+    get_opt
+      {sql|
+    SELECT @int{id}, @int{mov_limit} FROM clients WHERE id = %int{id}
+  |sql}
+      record_out]
+;;
+
+let execute_operation ~client_id ~(op : Operation.t) pool =
+  match op with
+  | Transaction data ->
+    Caqti_eio.Pool.use
+      (fun conn ->
+        transaction_query
+          ~client_id
+          ~value:data.value
+          ~transaction_type:data.transaction_type
+          ~description:data.description
+          conn)
+      pool
+  | _ -> failwith "TODO"
+;;
+
+let find_client id pool = Caqti_eio.Pool.use (fun conn -> client_query ~id conn) pool
diff --git a/lib/router.ml b/lib/router.ml
index cbff9fb..35cef34 100644
--- a/lib/router.ml
+++ b/lib/router.ml
@@ -14,16 +14,35 @@ module R = Map.Make (struct
     ;;
   end)
 
-let transactions_route =
-  let handler client_id (request : Request.t) =
-    let json : Yojson.Safe.t = `Assoc [ "limite", `Int 100000; "saldo", `Int (-9098) ] in
-    Response.of_string ~body:(Yojson.Safe.to_string json) `OK
-  in
-  (s "clientes" / int / s "transacoes" /? nil) @--> handler
-;;
+module Handler = struct
+  let transaction client_id (db_pool : Query.pool) (request : Request.t) =
+    let client_opt =
+      Option.join @@ Result.to_option @@ Query.find_client client_id db_pool
+    in
+    match client_opt with
+    | Some client ->
+      let insert_result =
+        let body = Result.to_option @@ Body.to_string request.body in
+        let json = Option.map Yojson.Safe.from_string body in
+        let decoded_op = Option.bind json (Utils.Decoder.decode Operation.decoder) in
+        match decoded_op with
+        | Some op ->
+          (match Query.execute_operation ~client_id ~op db_pool with
+           | Ok _ as ok -> ok
+           | Error e -> Error (`DB e))
+        | None -> Error (`Decoder "Invalid operation")
+      in
+      (match insert_result with
+       | Ok () ->
+         let json : Yojson.Safe.t =
+           `Assoc [ "limite", `Int 100000; "saldo", `Int (-9098) ]
+         in
+         Response.of_string ~body:(Yojson.Safe.to_string json) `OK
+       | Error _ -> Response.create (`Code 422))
+    | None -> Response.create `Not_found
+  ;;
 
-let balance_route =
-  let handler client_id (request : Request.t) =
+  let balance client_id (db_pool : Query.pool) (request : Request.t) =
     let json : Yojson.Safe.t =
       let balance =
         let total = `Int (-9098) in
@@ -35,15 +54,16 @@ let balance_route =
       `Assoc [ "saldo", balance; "ultimas_transacoes", last_transactions ]
     in
     Response.of_string ~body:(Yojson.Safe.to_string json) `OK
-  in
-  (s "clientes" / int / s "extrato" /? nil) @--> handler
-;;
+  ;;
+end
 
 let routes =
   List.fold_left
     ~f:(fun acc (v, r) -> R.add_to_list v r acc)
-    [ `GET, balance_route; `POST, transactions_route; `POST, balance_route ]
     ~init:R.empty
+    [ `GET, (s "clientes" / int / s "extrato" /? nil) @--> Handler.balance
+    ; `POST, (s "clientes" / int / s "transacoes" /? nil) @--> Handler.transaction
+    ]
 ;;
 
 let router = R.map one_of routes
diff --git a/lib/router.mli b/lib/router.mli
deleted file mode 100644
index c0b5915..0000000
--- a/lib/router.mli
+++ /dev/null
@@ -1 +0,0 @@
-val match_route : Piaf.Method.t -> string -> (Piaf.Request.t -> Piaf.Response.t) option
diff --git a/lib/utils.ml b/lib/utils.ml
new file mode 100644
index 0000000..00e003a
--- /dev/null
+++ b/lib/utils.ml
@@ -0,0 +1,121 @@
+module Decoder : sig
+  type 'a decoder
+
+  val decode : 'a decoder -> Yojson.Safe.t -> 'a option
+  val return : 'a -> 'a decoder
+  val fail : 'a decoder
+  val bind : 'a decoder -> ('a -> 'b decoder) -> 'b decoder
+  val map : ('a -> 'b) -> 'a decoder -> 'b decoder
+  val string : string decoder
+  val literal : string -> string decoder
+  val int : int decoder
+  val field : string -> 'a decoder -> 'a decoder
+  val list : 'a decoder -> 'a list decoder
+  val one_of : 'a decoder list -> 'a decoder
+
+  module Syntax : sig
+    val ( *> ) : 'a decoder -> 'b decoder -> 'b decoder
+    val ( <* ) : 'a decoder -> 'b decoder -> 'a decoder
+    val ( >>= ) : 'a decoder -> ('a -> 'b decoder) -> 'b decoder
+    val ( >>| ) : 'a decoder -> ('a -> 'b) -> 'b decoder
+    val ( <*> ) : ('a -> 'b) decoder -> 'a decoder -> 'b decoder
+    val ( <$> ) : ('a -> 'b) -> 'a decoder -> 'b decoder
+    val ( <: ) : string -> 'a decoder -> 'a decoder
+    val ( <|> ) : 'a decoder -> 'a decoder -> 'a decoder
+  end
+end = struct
+  type 'a decoder = Yojson.Safe.t -> 'a option
+
+  let decode decoder json = decoder json
+  let return v _ = Some v
+  let fail _ = None
+
+  let map f decoder json =
+    match decoder json with
+    | Some d -> Some (f d)
+    | None -> None
+  ;;
+
+  let bind decoder f json =
+    match decoder json with
+    | Some x -> f x `Null
+    | None -> None
+  ;;
+
+  let rec one_of decoders json =
+    match decoders with
+    | [] -> None
+    | decoder :: tl ->
+      (match decoder json with
+       | Some _ as x -> x
+       | None -> one_of tl json)
+  ;;
+
+  let string = function
+    | `String str -> Some str
+    | _ -> None
+  ;;
+
+  let literal str = function
+    | `String s when String.equal s str -> Some s
+    | _ -> None
+  ;;
+
+  let int = function
+    | `Int int -> Some int
+    | _ -> None
+  ;;
+
+  let field key decoder json =
+    try decoder @@ Yojson.Safe.Util.member key json with
+    | _ -> None
+  ;;
+
+  let list decoder json =
+    let rec helper acc = function
+      | [] -> Some []
+      | hd :: tl ->
+        (match decoder hd with
+         | Some _ as x -> helper (x :: acc) tl
+         | None -> None)
+    in
+    match json with
+    | `List list -> Option.map List.rev (helper [] list)
+    | _ -> None
+  ;;
+
+  module Syntax = struct
+    let ( *> ) decoder_a decoder_b yojson =
+      match decoder_a yojson with
+      | Some _ -> decoder_b yojson
+      | None -> None
+    ;;
+
+    let ( <* ) decoder_a decoder_b yojson =
+      match decoder_a yojson with
+      | Some value -> Option.map (fun _ -> value) (decoder_b yojson)
+      | None -> None
+    ;;
+
+    let ( >>= ) = bind
+    let ( >>| ) decoder f yojson = map f decoder yojson
+
+    let ( <*> ) decoder_a decoder_b input =
+      match decoder_a input with
+      | Some f ->
+        (match decoder_b input with
+         | Some x -> Some (f x)
+         | None -> None)
+      | None -> None
+    ;;
+
+    let ( <$> ) f decoder = decoder >>| f
+    let ( <: ) = field
+
+    let ( <|> ) decoder_a decoder_b input =
+      match decoder_a input with
+      | Some _ as value -> value
+      | None -> decoder_b input
+    ;;
+  end
+end
diff --git a/nginx.conf b/nginx.conf
index 60b677f..fc8933d 100644
--- a/nginx.conf
+++ b/nginx.conf
@@ -12,7 +12,7 @@ http {
     }
 
     server {
-        listen 9999; # Lembra da porta 9999 obrigatória?
+        listen 9999;
         
         location / {
             proxy_pass http://api;
diff --git a/script.sql b/script.sql
index f5da315..25e5ffe 100644
--- a/script.sql
+++ b/script.sql
@@ -1,14 +1,14 @@
 CREATE TABLE clients (
   id SERIAL PRIMARY KEY,
   name VARCHAR(50) NOT NULL,
-  limit INTEGER NOT NULL
+  mov_limit INTEGER NOT NULL
 );
 
-CREATE TYPE transaction_type AS ENUM ('c', 'd');
+CREATE TYPE transaction_type AS ENUM ('credit', 'debit');
 
 CREATE TABLE transactions (
   id SERIAL PRIMARY KEY,
-  client_id REFERENCES clients,
+  client_id INTEGER REFERENCES clients,
   value INTEGER NOT NULL,
   type transaction_type NOT NULL,
   description VARCHAR(10) NOT NULL,
@@ -17,12 +17,13 @@ CREATE TABLE transactions (
 
 CREATE TABLE balances (
   id SERIAL PRIMARY KEY,
-  client_id REFERENCES clients,
+  client_id INTEGER REFERENCES clients,
   value INTEGER NOT NULL
 );
 
+DO $$
 BEGIN
-  INSERT INTO clients (name, limit)
+  INSERT INTO clients (name, mov_limit)
   VALUES
       ('naruto', 1000 * 100),
       ('mob', 800 * 100),
@@ -31,3 +32,4 @@ BEGIN
   INSERT INTO balances (client_id, value)
       SELECT id, 0 FROM clients;
 END;
+$$