Enhancement/incremental community fields (#643)

* Update elm-community/list-extra

* Add structure to query multiple community fields

* Create initial structure and validate it on Community page

* Make uploads a requestable field

* Fix objectives and uploads signatures

* Introduce FieldError

* Refactor Objectives page to reload only objectives field and use new structure

* Reload objectives when entering community page, better visuals for objectives loading and error

* Only reload objectives on ActionEditor

* Requesst objectives field

* Fix Join page for logged in users

* Set fields as loading while fetching them

* Only reload objectives on ObjectiveEditor

* Remove unnecessary comment

* Remove unnecessary comment

* Use UpdateResult in CommunityPage.init

* Add docs to Field, FieldValue and FieldError

elm.json

@@ -26,7 +26,7 @@
             "elm/svg": "1.0.1",
             "elm/time": "1.0.0",
             "elm/url": "1.0.0",
-            "elm-community/list-extra": "8.2.4",
+            "elm-community/list-extra": "8.5.1",
             "elm-community/maybe-extra": "5.2.0",
             "elm-community/string-extra": "4.0.1",
             "jfmengels/elm-review": "2.3.2",

public/translations/amh-ETH.json

@@ -471,6 +471,7 @@
       "action_count": "{{actions}} ተግባራት",
       "complete": "ተጠናቅቋል",
       "edit": "አርትእ ዓላማዎችን",
+      "error_loading": "ግቦቹን ሲጭኑ አንድ የተሳሳተ ነገር ተከሰተ",
       "editor": {
         "not_found": "አልተገኘም",
         "error": "ዉይ የሆነ ችግር ተከስቷል!",

public/translations/cat-CAT.json

@@ -513,6 +513,7 @@
       "action_count": "{{actions}} accions",
       "complete": "Completat",
       "edit": "Edita l'objectiu",
+      "error_loading": "S'ha produït un error en carregar els objectius",
       "editor": {
         "not_found": "No trobat",
         "error": "Ui! Quelcom ha fallat",

public/translations/en-US.json

@@ -509,6 +509,7 @@
       "action_count": "{{actions}} actions",
       "complete": "Complete",
       "edit": "Edit objective",
+      "error_loading": "Something went wrong when loading objectives",
       "editor": {
         "not_found": "Not Found",
         "error": "Ops something went wrong!",

public/translations/es-ES.json

@@ -513,6 +513,7 @@
       "action_count": "{{actions}} acciones",
       "complete": "Terminado",
       "edit": "Editar objetivo",
+      "error_loading": "Ocurrió algo mal al cargar los objetivos",
       "editor": {
         "not_found": "No encontrado",
         "error": "¡Huy! Algo salió mal",

public/translations/pt-BR.json

@@ -517,6 +517,7 @@
       "action_count": "{{actions}} ações",
       "complete": "Completo",
       "edit": "Editar objetivo",
+      "error_loading": "Algo de errado aconteceu ao carregar os objetivos",
       "editor": {
         "not_found": "Não encontrado",
         "error": "Ops algo deu errado!",

src/elm/Community.elm

@@ -3,6 +3,9 @@ module Community exposing
     , CommunityPreview
     , CreateCommunityData
     , CreateCommunityDataInput
+    , Field(..)
+    , FieldError(..)
+    , FieldValue(..)
     , Invite
     , Metadata
     , Model
@@ -19,15 +22,24 @@ module Community exposing
     , encodeCreateObjectiveAction
     , encodeUpdateData
     , encodeUpdateObjectiveAction
+    , getField
     , inviteQuery
+    , isFieldLoading
     , isNonExistingCommunityError
     , logoBackground
+    , maybeFieldValue
+    , mergeFields
     , newCommunitySubscription
+    , queryForField
+    , queryForFields
+    , setFieldAsLoading
+    , setFieldValue
     , subdomainQuery
     , symbolQuery
     )
 
 import Action exposing (Action)
+import Api.Graphql
 import Cambiatus.Mutation as Mutation
 import Cambiatus.Object
 import Cambiatus.Object.Community as Community
@@ -52,7 +64,9 @@ import Html.Attributes exposing (class, classList, src)
 import Json.Decode as Decode exposing (Decoder)
 import Json.Decode.Pipeline exposing (required)
 import Json.Encode as Encode exposing (Value)
+import List.Extra
 import Profile
+import RemoteData exposing (RemoteData)
 import Session.Shared exposing (Shared)
 import Time exposing (Posix)
 import Utils
@@ -95,17 +109,143 @@ type alias Model =
     , productCount : Int
     , orderCount : Int
     , members : List Profile.Minimal
-    , objectives : List Objective
+    , objectives : RemoteData (Graphql.Http.Error (List Objective)) (List Objective)
     , hasObjectives : Bool
     , hasShop : Bool
     , hasKyc : Bool
     , hasAutoInvite : Bool
     , validators : List Eos.Name
-    , uploads : List String
+    , uploads : RemoteData (Graphql.Http.Error (List String)) (List String)
     , website : Maybe String
     }
 
 
+{-| In order to be able to query for fields separately from the community (such
+as objectives and uploads), we need to add a `Field` constructor to represent
+that field. The constructor's name should be the name of the field followed by
+`Field` (e.g. `ObjectivesField`).
+
+In order to have a nice API, we also need types to wrap the success and error
+cases. That's why we have `FieldValue` and `FieldError`.
+
+If you want to add a new field that isn't loaded by default (usually Lists are
+good candidates):
+
+1.  Add the field to the `Model`. It's type should be in the format
+    `RemoteData (Graphql.Http.Error field) field`
+2.  Add a new constructor to this `Field` type following the practices described above
+3.  Add a new constructor to `FieldValue` (see `FieldValue`'s documentation for
+    more info)
+4.  Fill in the functions that use `Field` and `FieldValue` (the compiler will
+    let you know which ones)
+
+Pages can use this type to request separate fields from `LoggedIn`, using
+`LoggedIn.External` messages, specifying which field they want. There are two
+variants they can use to do so:
+
+1.  `RequestedCommunityField`: Checks if the field is loaded. If so, send a
+    `BroadcastMsg` with the field. If not, queries the backend for that field,
+    and once the result comes in, sends a `BroadcastMsg`
+2.  `RequestedReloadCommunityField`: Always queries for the field, and sends the
+    result as a `BroadcastMsg`
+
+-}
+type Field
+    = ObjectivesField
+    | UploadsField
+
+
+{-| `FieldValue` is useful to wrap results of queries for fields that aren't
+loaded in by default with the community (such as objectives and uploads). The
+constructor's name should be the name of the field followed by `Value`, and
+should hold the actual value of that field (e.g. `ObjectivesValue (List Objetive)`).
+-}
+type FieldValue
+    = ObjectivesValue (List Objective)
+    | UploadsValue (List String)
+
+
+{-| When we want to extract a field that is not loaded by default with the
+community, and there is an error, we need to know if it was an error when
+fetching the community or when fetching the actual field.
+-}
+type FieldError a
+    = CommunityError (Graphql.Http.Error (Maybe Model))
+    | FieldError a
+
+
+getField :
+    RemoteData (Graphql.Http.Error (Maybe Model)) Model
+    -> (Model -> RemoteData err field)
+    -> RemoteData (FieldError err) ( Model, field )
+getField remoteDataModel accessor =
+    remoteDataModel
+        |> RemoteData.mapError CommunityError
+        |> RemoteData.andThen
+            (\model ->
+                accessor model
+                    |> RemoteData.map (\field -> ( model, field ))
+                    |> RemoteData.mapError FieldError
+            )
+
+
+setFieldValue : FieldValue -> Model -> Model
+setFieldValue fieldValue model =
+    case fieldValue of
+        ObjectivesValue objectives ->
+            { model | objectives = RemoteData.Success objectives }
+
+        UploadsValue uploads ->
+            { model | uploads = RemoteData.Success uploads }
+
+
+setFieldAsLoading : Field -> Model -> Model
+setFieldAsLoading field model =
+    case field of
+        ObjectivesField ->
+            { model | objectives = RemoteData.Loading }
+
+        UploadsField ->
+            { model | uploads = RemoteData.Loading }
+
+
+isFieldLoading : Field -> Model -> Bool
+isFieldLoading field model =
+    case field of
+        ObjectivesField ->
+            RemoteData.isLoading model.objectives
+
+        UploadsField ->
+            RemoteData.isLoading model.uploads
+
+
+maybeFieldValue : Field -> Model -> Maybe FieldValue
+maybeFieldValue field model =
+    case field of
+        ObjectivesField ->
+            model.objectives
+                |> RemoteData.toMaybe
+                |> Maybe.map ObjectivesValue
+
+        UploadsField ->
+            model.uploads
+                |> RemoteData.toMaybe
+                |> Maybe.map UploadsValue
+
+
+mergeFields : RemoteData x Model -> Model -> Model
+mergeFields loadedCommunity newCommunity =
+    case loadedCommunity of
+        RemoteData.Success oldCommunity ->
+            { newCommunity
+                | objectives = oldCommunity.objectives
+                , uploads = oldCommunity.uploads
+            }
+
+        _ ->
+            newCommunity
+
+
 
 -- GraphQL
 
@@ -141,13 +281,13 @@ communitySelectionSet =
         |> with Community.productCount
         |> with Community.orderCount
         |> with (Community.members Profile.minimalSelectionSet)
-        |> with (Community.objectives objectiveSelectionSet)
+        |> SelectionSet.hardcoded RemoteData.NotAsked
         |> with Community.hasObjectives
         |> with Community.hasShop
         |> with Community.hasKyc
         |> with Community.autoInvite
         |> with (Community.validators (Eos.nameSelectionSet Profile.account))
-        |> with (Community.uploads Upload.url)
+        |> SelectionSet.hardcoded RemoteData.NotAsked
         |> with Community.website
 
 
@@ -175,6 +315,55 @@ newCommunitySubscription symbol =
     Subscription.newcommunity args selectionSet
 
 
+selectionSetForField : Field -> SelectionSet FieldValue Cambiatus.Object.Community
+selectionSetForField field =
+    case field of
+        ObjectivesField ->
+            Community.objectives objectiveSelectionSet
+                |> SelectionSet.map ObjectivesValue
+
+        UploadsField ->
+            Community.uploads Upload.url
+                |> SelectionSet.map UploadsValue
+
+
+queryForField :
+    Eos.Symbol
+    -> Shared
+    -> String
+    -> Field
+    -> (RemoteData (Graphql.Http.Error (Maybe FieldValue)) (Maybe FieldValue) -> msg)
+    -> Cmd msg
+queryForField symbol shared authToken field toMsg =
+    Api.Graphql.query shared
+        (Just authToken)
+        (field
+            |> selectionSetForField
+            |> Query.community (\optionals -> { optionals | symbol = Present <| Eos.symbolToString symbol })
+        )
+        toMsg
+
+
+queryForFields :
+    Eos.Symbol
+    -> Shared
+    -> String
+    -> List Field
+    -> (RemoteData (Graphql.Http.Error (List FieldValue)) (List FieldValue) -> msg)
+    -> Cmd msg
+queryForFields symbol shared authToken fields toMsg =
+    Api.Graphql.query shared
+        (Just authToken)
+        (fields
+            |> List.Extra.unique
+            |> List.map selectionSetForField
+            |> SelectionSet.list
+            |> Query.community (\optionals -> { optionals | symbol = Present <| Eos.symbolToString symbol })
+            |> SelectionSet.withDefault []
+        )
+        toMsg
+
+
 symbolQuery : Eos.Symbol -> SelectionSet (Maybe Model) RootQuery
 symbolQuery symbol =
     Query.community (\optionals -> { optionals | symbol = Present <| Eos.symbolToString symbol }) communitySelectionSet

src/elm/Main.elm

@@ -823,8 +823,7 @@ updateLoggedInUResult toStatus toMsg model uResult =
                                 )
                                 updateResult.afterAuthMsg
                       }
-                    , Cmd.map toMsg updateResult.externalCmd
-                        :: Cmd.map (Page.GotLoggedInMsg >> GotPageMsg) updateResult.cmd
+                    , Cmd.map (Page.GotLoggedInMsg >> GotPageMsg) updateResult.cmd
                         :: broadcastCmd
                         :: cmds_
                     )
@@ -1225,7 +1224,7 @@ changeRouteTo maybeRoute model =
 
         Just Route.Community ->
             (\l -> CommunityPage.init l)
-                >> updateStatusWith Community GotCommunityMsg model
+                >> updateLoggedInUResult Community GotCommunityMsg model
                 |> withLoggedIn Route.Community
 
         Just Route.CommunitySettings ->
@@ -1275,12 +1274,12 @@ changeRouteTo maybeRoute model =
 
         Just (Route.NewAction objectiveId) ->
             (\l -> ActionEditor.init l objectiveId Nothing)
-                >> updateStatusWith ActionEditor GotActionEditorMsg model
+                >> updateLoggedInUResult ActionEditor GotActionEditorMsg model
                 |> withLoggedIn (Route.NewAction objectiveId)
 
         Just (Route.EditAction objectiveId actionId) ->
             (\l -> ActionEditor.init l objectiveId (Just actionId))
-                >> updateStatusWith ActionEditor GotActionEditorMsg model
+                >> updateLoggedInUResult ActionEditor GotActionEditorMsg model
                 |> withLoggedIn (Route.EditAction objectiveId actionId)
 
         Just (Route.Claim objectiveId actionId claimId) ->