Merge pull request #76 from fsprojects/optional-defaultarg

Add support for same-attribute if-not-exists updates

build.fsx

@@ -24,7 +24,7 @@ System.Environment.GetCommandLineArgs()
 #r "nuget: Fake.IO.FileSystem"
 #r "nuget: Fake.Api.GitHub"
 #r "nuget: Octokit"
-#r "nuget: MSBuild.StructuredLogger, Version=2.1.820"
+#r "nuget: MSBuild.StructuredLogger, Version=2.2.243"
 
 open Fake.Core
 open Fake.DotNet

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "8.0.100",
+    "version": "8.0.302",
     "rollForward": "latestMajor"
   }
 }

src/FSharp.AWS.DynamoDB/Expression/UpdateExpr.fs

@@ -295,7 +295,9 @@ let extractUpdateOps (exprs: IntermediateUpdateExprs) =
         | SpecificCall2 <@ List.append @> (None, _, _, [ left; right ]) ->
             UpdateValue.EList_Append (extractOperand pickler left) (extractOperand pickler right)
 
-        | SpecificCall2 <@ defaultArg @> (None, _, _, [ AttributeGet attr; operand ]) ->
+        | SpecificCall2 <@ defaultArg @> (None, _, _, [ AttributeGet attr; operand ])
+        | OptionSome(SpecificCall2 <@ defaultArg @> (None, _, _, [ AttributeGet attr; operand ]))
+        | SpecificCall2 <@ defaultArg @> (None, _, _, [ OptionSome(AttributeGet attr); operand ]) ->
             match extractOperand attr.Pickler operand with
             | Undefined -> invalidExpr ()
             | op -> If_Not_Exists(attr.Id, op)

src/FSharp.AWS.DynamoDB/Utils/Utils.fs

@@ -233,6 +233,16 @@ module internal Utils =
                 None
         | _ -> None
 
+    let (|OptionSome|_|) (e: Expr) =
+        match e with
+        | NewUnionCase(uci, [ v ]) ->
+            let dt = uci.DeclaringType
+            if dt.IsGenericType && dt.GetGenericTypeDefinition() = typedefof<_ option> && uci.Name = (nameof Some) then
+                Some v
+            else
+                None
+        | _ -> None
+
     type Async with
 
         /// Raise an exception

tests/FSharp.AWS.DynamoDB.Tests/UpdateExpressionTests.fs

@@ -243,6 +243,35 @@ type ``Update Expression Tests``(fixture: TableFixture) =
         let item' = table.UpdateItem(key, <@ fun (r: R) -> { r with String = defaultArg r.Optional "<undefined>" } @>)
         test <@ "<undefined>" = item'.String @>
 
+    [<Fact>]
+    let ``Update using defaultArg combinator on the same optional attribute (None)`` () =
+        let item = { mkItem () with Optional = None }
+        let key = table.PutItem item
+        let item' = table.UpdateItem(key, <@ fun (r: R) -> { r with Optional = defaultArg r.Optional "<undefined>" |> Some } @>)
+        test <@ Some "<undefined>" = item'.Optional @>
+
+    [<Fact>]
+    let ``Update using defaultArg combinator on the same optional attribute (Some)`` () =
+        let item = { mkItem () with Optional = Some(guid ()) }
+        let key = table.PutItem item
+        let item' = table.UpdateItem(key, <@ fun (r: R) -> { r with Optional = defaultArg r.Optional "<undefined>" |> Some } @>)
+        test <@ item.Optional = item'.Optional @>
+
+    [<Fact>]
+    let ``Update using defaultArg combinator on the same non-optional attribute (None)`` () =
+        let item = mkItem ()
+        let key = table.PutItem item
+        clearAttribute table key "String"
+        let item' = table.UpdateItem(key, <@ fun (r: R) -> { r with String = defaultArg (Some r.String) "<undefined>" } @>)
+        test <@ "<undefined>" = item'.String @>
+
+    [<Fact>]
+    let ``Update using defaultArg combinator on the same non-optional attribute (Some)`` () =
+        let item = mkItem ()
+        let key = table.PutItem item
+        let item' = table.UpdateItem(key, <@ fun (r: R) -> { r with String = defaultArg (Some r.String) "<undefined>" } @>)
+        test <@ item.String = item'.String @>
+
     [<Fact>]
     let ``Update int set with add element`` () =
         let item = { mkItem () with IntSet = set [ 1L; 2L ] }

tests/FSharp.AWS.DynamoDB.Tests/Utils.fs

@@ -2,6 +2,7 @@
 
 open System
 open System.IO
+open System.Collections.Generic
 
 open FsCheck
 open Swensen.Unquote
@@ -10,6 +11,7 @@ open Xunit
 open FSharp.AWS.DynamoDB
 
 open Amazon.DynamoDBv2
+open Amazon.DynamoDBv2.Model
 open Amazon.Runtime
 
 [<AutoOpen>]
@@ -28,6 +30,19 @@ module Utils =
         new AmazonDynamoDBClient(credentials, config) :> IAmazonDynamoDB
 
 
+    let clearAttribute (table: TableContext<'T>) (key: TableKey) (attribute: string) =
+        let keyAttr = table.Template.ToAttributeValues key
+        table.Client.UpdateItemAsync(
+            new UpdateItemRequest(
+                TableName = table.TableName,
+                Key = keyAttr,
+                AttributeUpdates = Dictionary(Map.ofSeq [ attribute, new AttributeValueUpdate(Action = AttributeAction.DELETE) ])
+            )
+        )
+        |> Async.AwaitTask
+        |> Async.RunSynchronously
+        |> ignore
+
     type FsCheckGenerators =
         static member MemoryStream =
             Arb.generate<byte[] option>