Prototype sending multiple mime types (for Plotly initially)

#142

Author: cgravill

Diff for: src/IfSharp.Kernel/App.fs

@@ -48,13 +48,12 @@ module App =
 
         if value <> null then
             if sbPrint.Length > 0 then
-                Kernel.Value.SendDisplayData("text/plain", sbPrint.ToString())
+                Kernel.Value.SendDisplayData( Map.ofList [("text/plain", sbPrint.ToString() :> obj)])
                 sbPrint.Clear() |> ignore
 
             let printer = Printers.findDisplayPrinter (value.GetType())
-            let (_, callback) = printer
-            let callbackValue = callback(value)
-            Kernel.Value.SendDisplayData(callbackValue.ContentType, callbackValue.Data)
+            let callbackValue = printer(value)
+            Kernel.Value.SendDisplayData callbackValue
 
     /// Global help function
     let Help (value : obj) = 

Diff for: src/IfSharp.Kernel/Kernel.fs

@@ -85,7 +85,7 @@ type IfSharpKernel(connectionInformation : ConnectionInformation) =
     /// Serializes any object into JSON
     let serialize (obj) =
         let ser = JsonSerializer()
-        let sw = new StringWriter()
+        use sw = new StringWriter()
         ser.Serialize(sw, obj)
         sw.ToString()
 
@@ -214,17 +214,14 @@ type IfSharpKernel(connectionInformation : ConnectionInformation) =
         sendMessage shellSocket msg "kernel_info_reply" content
 
     /// Sends display data information immediately
-    let sendDisplayData (contentType) (displayItem) (messageType) =        
+    let sendDisplayData (data: Map<string, obj>) (messageType) =        
         if lastMessage.IsSome then
 
-            let d = Dictionary<string,obj>()
-            d.Add(contentType, displayItem)
-
-            let reply = { execution_count = executionCount; data = d; metadata = Dictionary<string,obj>() }
+            let reply = { execution_count = executionCount; data = data; metadata = Dictionary<string,obj>() }
             sendMessage ioSocket lastMessage.Value messageType reply
 
     /// Sends a message to pyout
-    let pyout (message) = sendDisplayData "text/plain" message "pyout"
+    let pyout (message) = sendDisplayData (Map.ofList[("text/plain", message)]) "pyout"
 
     /// Preprocesses the code and evaluates it
     let preprocessCode(code) = 
@@ -343,9 +340,9 @@ type IfSharpKernel(connectionInformation : ConnectionInformation) =
                             if it.ReflectionType <> typeof<unit> then
                                 let printer =
                                     Printers.findDisplayPrinter it.ReflectionType
-                                let (_, callback) = printer
-                                let callbackValue = callback(it.ReflectionValue)
-                                sendDisplayData callbackValue.ContentType callbackValue.Data "pyout"
+                                let callbackValue = printer(it.ReflectionValue)
+                                sendDisplayData callbackValue "pyout"
+
 
                         | None -> ()
 
@@ -360,7 +357,7 @@ type IfSharpKernel(connectionInformation : ConnectionInformation) =
                 sendError err
 
         if sbPrint.Length > 0 then
-            sendDisplayData "text/plain" (sbPrint.ToString()) "display_data"
+            sendDisplayData (Map.ofList[("text/plain", sbPrint.ToString() :> obj)]) "display_data"
 
         // we are now idle
         sendStateIdle msg
@@ -431,7 +428,7 @@ type IfSharpKernel(connectionInformation : ConnectionInformation) =
             |]
             |> Array.filter (fun x -> x.Subcategory <> "parse")
 
-        sendDisplayData "errors" newErrors "display_data"
+        sendDisplayData (Map.ofList[("errors", newErrors :> obj)]) "display_data"
         sendMessage (shellSocket) (msg) ("complete_reply") (newContent)
 
     /// Handles a 'connect_request' message
@@ -533,8 +530,8 @@ type IfSharpKernel(connectionInformation : ConnectionInformation) =
         payload.Add( { html = ""; source = "page"; start_line_number = 1; text = text })
 
     /// Adds display data to the list of display data to send to the client
-    member __.SendDisplayData (contentType, displayItem) =
-        sendDisplayData contentType displayItem "display_data"
+    member __.SendDisplayData data =
+        sendDisplayData data "display_data"
 
     /// Starts the kernel asynchronously
     member __.StartAsync() = 

Diff for: src/IfSharp.Kernel/Printers.fs

@@ -6,18 +6,24 @@ open System.Web
 
 module Printers =
 
-    let mutable internal displayPrinters : list<Type * (obj -> BinaryOutput)> = []
+    let mutable internal displayPrinters : list<Type * (obj -> Map<string,obj>)> = []
+    let mutable internal displayMultiPrinters : list<Type * (obj -> Map<string,obj>)> = []
 
     /// Convenience method for encoding a string within HTML
     let internal htmlEncode(str) = HttpUtility.HtmlEncode(str)
 
     /// Adds a custom display printer for extensibility
     let addDisplayPrinter(printer : 'T -> BinaryOutput) =
-        displayPrinters <- (typeof<'T>, (fun (x:obj) -> printer (unbox x))) :: displayPrinters
+        displayPrinters <- (typeof<'T>, (fun (x:obj) ->
+                                            let binaryOutput = printer (unbox x)
+                                            Map.ofList [(binaryOutput.ContentType, binaryOutput.Data)])) :: displayPrinters
+
+    let addDisplayMultiPrinter(printer : 'T -> Map<string,obj>) =
+        displayMultiPrinters <- (typeof<'T>, (fun (x:obj) -> printer (unbox x))) :: displayMultiPrinters
 
     /// Default display printer
     let defaultDisplayPrinter(x) =
-        { ContentType = "text/plain"; Data = sprintf "%A" x }
+        Map.ofList [("text/plain", sprintf "%A" x :> obj)]
 
     //https://technet.microsoft.com/en-us/ee353649(v=vs.85)
     let mapToFSharpAliases fullType name =
@@ -59,7 +65,7 @@ module Printers =
 
     let functionPrinter(func:obj) =
         let funcArguments = possiblyAFuncAsString (func.GetType())
-        { ContentType = "text/plain"; Data = sprintf "%A : %s" func funcArguments }
+        Map.ofList [("text/plain", sprintf "%A : %s" func funcArguments :> obj)]
 
     /// Finds a display printer based off of the type
     let findDisplayPrinter(findType) =
@@ -70,19 +76,27 @@ module Printers =
             |> Seq.map (fun (t, p) -> t, fun o -> 
                 let extras, html = p o
                 let extras = extras |> Seq.map snd |> String.concat ""
-                { ContentType = "text/html"; Data = extras + html })
+                //let binaryOutput = { ContentType = "text/html"; Data = extras + html }
+                Map.ofList [("text/html", (extras + html) :> obj)])
 
         let printers =
             Seq.append displayPrinters extraPrinters
             |> Seq.filter (fun (t, _) -> t.IsAssignableFrom(findType))
             |> Seq.toList
 
+        let multiPrinters =
+            displayMultiPrinters
+            |> Seq.filter (fun (t, _) -> t.IsAssignableFrom(findType))
+            |> Seq.toList
+
         if printers.Length > 0 then
-            printers.Head
+            snd printers.Head
+        elif multiPrinters.Length > 0 then
+            snd multiPrinters.Head
         elif FSharp.Reflection.FSharpType.IsFunction findType then
-            (typeof<Type>, functionPrinter)
+            functionPrinter
         else
-            (typeof<obj>, defaultDisplayPrinter)
+            defaultDisplayPrinter
 
     /// Adds default display printers
     let addDefaultDisplayPrinters() =

Diff for: src/IfSharp.Kernel/ShellMessages.fs

@@ -450,7 +450,7 @@ type Pyout =
         // # data and metadata are identical to a display_data message.
         // # the object being displayed is that passed to the display hook,
         // # i.e. the *result* of the execution.
-        data: Dictionary<string,obj>;
+        data: Map<string,obj>;
         metadata: Dictionary<string,obj>;
     }
 

Diff for: src/IfSharp.Kernel/helpers/XPlot.Plotly.fsx

@@ -8,6 +8,7 @@ open IfSharp.Kernel.Globals
 
 do
     Printers.addDisplayPrinter(fun (plot: PlotlyChart) ->
+        
         { ContentType = "text/html"; Data = plot.GetInlineHtml() })
 
     //System.Net.ServicePointManager.SecurityProtocol <- System.Net.SecurityProtocolType.Tls12