1 files changed, 53 insertions, 0 deletions
diff --git a/elm/Lib/Api.elm b/elm/Lib/Api.elm
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+module Lib.Api exposing (..)
+
+import Json.Encode as JE
+import Http
+
+import Gen.Api exposing (..)
+
+
+-- Handy state enum for forms
+type State
+  = Normal
+  | Loading
+  | Error Response
+
+
+-- User-friendly error message if the response isn't what the code expected.
+-- (Technically a good chunk of this function could also be automatically
+-- generated by Elm.pm, but that wouldn't really have all that much value).
+showResponse : Response -> String
+showResponse res =
+  let unexp = "Unexpected response, please report a bug."
+  in case res of
+    HTTPError (Http.Timeout)        -> "Network timeout, please try again later."
+    HTTPError (Http.NetworkError)   -> "Network error, please try again later."
+    HTTPError (Http.BadStatus r)    -> "Server error " ++ String.fromInt r ++ ", please try again later, or report an issue if this persists."
+    HTTPError (Http.BadBody r)      -> "Invalid response from the server, please report a bug (debug info: " ++ r ++")."
+    HTTPError (Http.BadUrl _)       -> unexp
+    Success                         -> unexp
+    CSRF                            -> "Invalid CSRF token, please refresh the page and try again."
+    Invalid                         -> "Invalid form data, please report a bug."
+    Unauth                          -> "You do not have the permission to perform this action."
+    Unchanged                       -> "No changes"
+    Changed _ _                     -> unexp
+    Content _                       -> unexp
+
+
+expectResponse : (Response -> msg) -> Http.Expect msg
+expectResponse msg =
+  let
+    res r = msg <| case r of
+      Err e -> HTTPError e
+      Ok v -> v
+  in Http.expectJson res decode
+
+
+-- Send a POST request with a JSON body to the VNDB API and get a Response back.
+post : String -> JE.Value -> (Response -> msg) -> Cmd msg
+post url body msg =
+  Http.post
+    { url = url
+    , body = Http.jsonBody body
+    , expect = expectResponse msg
+    }