Merge #11564

11564: [sdk/dotnet/nodejs] Add InvokeSingle variants to dotnet and nodejs SDKs r=Zaid-Ajaj a=Zaid-Ajaj

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# Description

Needed for #11418 where we have invoke calls that return a simple type (such as `number`) but the runtime and engine _require_ the outputs to be a struct (as per the RPC definition) so here we are adding variants of `invoke` that unwraps the returned object and gets the first value from that object.

For example, a provider with a schema `outputs: { type: "number" }` will have an invoke implementation that returns `{ __result: 42.0 }`, in these case (non-object return types) we use `InvokeSingle` instead of `Invoke`

> It doesn't matter what the name of the key is, we always get the first value by first key.

## Checklist

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- [ ] I have added tests that prove my fix is effective or that my feature works
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User-facing changes require a CHANGELOG entry.
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- [x] I have run `make changelog` and committed the `changelog/pending/<file>` documenting my change
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- [ ] Yes, there are changes in this PR that warrants bumping the Pulumi Service API version
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Co-authored-by: Zaid Ajaj <zaid.naom@gmail.com>

changelog/pending/20221206--sdk-dotnet-nodejs--add-inokesingle-variants-to-dotnet-and-nodejs-sdks.yaml

@@ -0,0 +1,4 @@
+changes:
+- type: feat
+  scope: sdk/dotnet,nodejs
+  description: Add InvokeSingle variants to dotnet and nodejs SDKs

sdk/dotnet/Pulumi/Deployment/DeploymentInstance.cs

@@ -50,6 +50,22 @@ internal DeploymentInstance(IDeployment deployment)
         public Output<T> Invoke<T>(string token, InvokeArgs args, InvokeOptions? options = null)
             => _deployment.Invoke<T>(token, args, options);
 
+        /// <summary>
+        /// Dynamically invokes the function '<paramref name="token"/>', which is offered by a
+        /// provider plugin.
+        /// <para/>
+        /// The result of <see cref="InvokeSingle"/> will be a <see cref="Output"/> resolved to the
+        /// result value of the provider plugin.
+        /// <para/>
+        /// Similar to the earlier <see cref="InvokeSingleAsync"/>, but supports passing input values
+        /// and returns an Output value.
+        /// <para/>
+        /// The <paramref name="args"/> inputs can be a bag of computed values(including, `T`s,
+        /// <see cref="Task{TResult}"/>s, <see cref="Output{T}"/>s etc.).
+        /// </summary>
+        public Output<T> InvokeSingle<T>(string token, InvokeArgs args, InvokeOptions? options = null)
+            => _deployment.InvokeSingle<T>(token, args, options);
+
         /// <summary>
         /// Dynamically invokes the function '<paramref name="token"/>', which is offered by a
         /// provider plugin.
@@ -63,6 +79,19 @@ public Output<T> Invoke<T>(string token, InvokeArgs args, InvokeOptions? options
         public Task<T> InvokeAsync<T>(string token, InvokeArgs args, InvokeOptions? options = null)
             => _deployment.InvokeAsync<T>(token, args, options);
 
+        /// <summary>
+        /// Dynamically invokes the function '<paramref name="token"/>', which is offered by a
+        /// provider plugin.
+        /// <para/>
+        /// The result of <see cref="InvokeSingleAsync"/> will be a <see cref="Task"/> resolved to the
+        /// result value of the provider plugin which is expected to be a dictionary with single value.
+        /// <para/>
+        /// The <paramref name="args"/> inputs can be a bag of computed values(including, `T`s,
+        /// <see cref="Task{TResult}"/>s, <see cref="Output{T}"/>s etc.).
+        /// </summary>
+        public Task<T> InvokeSingleAsync<T>(string token, InvokeArgs args, InvokeOptions? options = null)
+            => _deployment.InvokeSingleAsync<T>(token, args, options);
+
         /// <summary>
         /// Same as <see cref="InvokeAsync{T}(string, InvokeArgs, InvokeOptions)"/>, however the
         /// return value is ignored.

sdk/dotnet/Pulumi/Deployment/Deployment_Invoke.cs

@@ -1,6 +1,7 @@
 // Copyright 2016-2021, Pulumi Corporation
 
 using System;
+using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Linq;
 using System.Threading.Tasks;
@@ -18,9 +19,21 @@ Task IDeployment.InvokeAsync(string token, InvokeArgs args, InvokeOptions? optio
         Task<T> IDeployment.InvokeAsync<T>(string token, InvokeArgs args, InvokeOptions? options)
             => InvokeAsync<T>(token, args, options, convertResult: true);
 
+        async Task<T> IDeployment.InvokeSingleAsync<T>(string token, InvokeArgs args, InvokeOptions? options)
+        {
+            var outputs = await InvokeAsync<Dictionary<string, T>>(token, args, options, convertResult: true);
+            return outputs.Values.First();
+        }
+
         Output<T> IDeployment.Invoke<T>(string token, InvokeArgs args, InvokeOptions? options)
             => new Output<T>(RawInvoke<T>(token, args, options));
 
+        Output<T> IDeployment.InvokeSingle<T>(string token, InvokeArgs args, InvokeOptions? options)
+        {
+            var outputResult = new Output<Dictionary<string, T>>(RawInvoke<Dictionary<string, T>>(token, args, options));
+            return outputResult.Apply(outputs => outputs.Values.First());
+        }
+
         private async Task<OutputData<T>> RawInvoke<T>(string token, InvokeArgs args, InvokeOptions? options)
         {
             // This method backs all `Fn.Invoke()` calls that generate

sdk/dotnet/Pulumi/Deployment/IDeployment.cs

@@ -38,6 +38,18 @@ internal interface IDeployment
         /// </summary>
         Task<T> InvokeAsync<T>(string token, InvokeArgs args, InvokeOptions? options = null);
 
+        /// <summary>
+        /// Dynamically invokes the function '<paramref name="token"/>', which is offered by a
+        /// provider plugin.
+        /// <para/>
+        /// The result of <see cref="InvokeSingleAsync"/> will be a <see cref="Task"/> resolved to the
+        /// result value of the provider plugin that returns a bag of properties with a single value that is returned.
+        /// <para/>
+        /// The <paramref name="args"/> inputs can be a bag of computed values(including, `T`s,
+        /// <see cref="Task{TResult}"/>s, <see cref="Output{T}"/>s etc.).
+        /// </summary>
+        Task<T> InvokeSingleAsync<T>(string token, InvokeArgs args, InvokeOptions? options = null);
+
         /// <summary>
         /// Dynamically invokes the function '<paramref name="token"/>', which is offered by a
         /// provider plugin.
@@ -50,6 +62,18 @@ internal interface IDeployment
         /// </summary>
         Output<T> Invoke<T>(string token, InvokeArgs args, InvokeOptions? options = null);
 
+        /// <summary>
+        /// Dynamically invokes the function '<paramref name="token"/>', which is offered by a
+        /// provider plugin.
+        /// <para/>
+        /// The result of <see cref="InvokeSingle"/> will be a <see cref="Output"/> resolved to the
+        /// result value of the provider plugin that returns a bag of properties with a single value that is returned.
+        /// <para/>
+        /// The <paramref name="args"/> inputs can be a bag of computed values(including, `T`s,
+        /// <see cref="Task{TResult}"/>s, <see cref="Output{T}"/>s etc.).
+        /// </summary>
+        Output<T> InvokeSingle<T>(string token, InvokeArgs args, InvokeOptions? options = null);
+
         /// <summary>
         /// Same as <see cref="InvokeAsync{T}(string, InvokeArgs, InvokeOptions)"/>, however the
         /// return value is ignored.

sdk/dotnet/Pulumi/PublicAPI.Shipped.txt

@@ -91,6 +91,7 @@ Pulumi.DeploymentInstance.Call(string token, Pulumi.CallArgs args, Pulumi.Resour
 Pulumi.DeploymentInstance.Call<T>(string token, Pulumi.CallArgs args, Pulumi.Resource self = null, Pulumi.CallOptions options = null) -> Pulumi.Output<T>
 Pulumi.DeploymentInstance.InvokeAsync(string token, Pulumi.InvokeArgs args, Pulumi.InvokeOptions options = null) -> System.Threading.Tasks.Task
 Pulumi.DeploymentInstance.InvokeAsync<T>(string token, Pulumi.InvokeArgs args, Pulumi.InvokeOptions options = null) -> System.Threading.Tasks.Task<T>
+Pulumi.DeploymentInstance.InvokeSingleAsync<T>(string token, Pulumi.InvokeArgs args, Pulumi.InvokeOptions options = null) -> System.Threading.Tasks.Task<T>
 Pulumi.DeploymentInstance.IsDryRun.get -> bool
 Pulumi.DeploymentInstance.ProjectName.get -> string
 Pulumi.DeploymentInstance.StackName.get -> string
@@ -395,4 +396,5 @@ static Pulumi.Urn.Create(Pulumi.Input<string> name, Pulumi.Input<string> type, P
 static readonly Pulumi.CallArgs.Empty -> Pulumi.CallArgs
 static readonly Pulumi.InvokeArgs.Empty -> Pulumi.InvokeArgs
 static readonly Pulumi.ResourceArgs.Empty -> Pulumi.ResourceArgs
-Pulumi.DeploymentInstance.Invoke<T>(string token, Pulumi.InvokeArgs args, Pulumi.InvokeOptions options = null) -> Pulumi.Output<T>
+Pulumi.DeploymentInstance.Invoke<T>(string token, Pulumi.InvokeArgs args, Pulumi.InvokeOptions options = null) -> Pulumi.Output<T>
+Pulumi.DeploymentInstance.InvokeSingle<T>(string token, Pulumi.InvokeArgs args, Pulumi.InvokeOptions options = null) -> Pulumi.Output<T>

sdk/nodejs/runtime/invoke.ts

@@ -74,6 +74,19 @@ export function invoke(tok: string, props: Inputs, opts: InvokeOptions = {}): Pr
     return invokeAsync(tok, props, opts);
 }
 
+/*
+ * `invokeSingle` dynamically invokes the function, `tok`, which is offered by a provider plugin.
+ * Similar to `invoke`, but returns a single value instead of an object with a single key.
+ */
+export function invokeSingle(tok: string, props: Inputs, opts: InvokeOptions = {}): Promise<any> {
+    return invokeAsync(tok, props, opts).then(outputs => {
+        // assume outputs have a single key
+        const keys = Object.keys(outputs);
+        // return the first key's value from the outputs
+        return outputs[keys[0]];
+    });
+}
+
 export async function streamInvoke(
     tok: string,
     props: Inputs,