GH-2319: Increase the grpc.MaxCallRecvMsgSize (#3201)

Fixes: #2319

In #2319, a user is hitting the gRPC limit on the message size the
server can receive when uploading ec2 user-data

This commit doubles the limit that can be sent from `1024*1024*4` to
`1024*1024*8`

CHANGELOG.md

@@ -7,6 +7,8 @@ CHANGELOG
   [#3170](https://github.com/pulumi/pulumi/pull/3170)
 - Read operations are no longer considered changes for the purposes of `--expect-no-changes`.
   [#3197](https://github.com/pulumi/pulumi/pull/3197)
+- Increase the MaxCallRecvMsgSize for interacting with the gRPC server. 
+  [#3201](https://github.com/pulumi/pulumi/pull/3201)
 
 ## 1.0.0 (2019-09-03)
 

pkg/resource/plugin/plugin.go

@@ -55,6 +55,9 @@ type plugin struct {
 // pluginRPCConnectionTimeout dictates how long we wait for the plugin's RPC to become available.
 var pluginRPCConnectionTimeout = time.Second * 10
 
+// pluginRPCMaxMessageSize raises the gRPC Max Message size from `4194304` to `419430400`
+var pluginRPCMaxMessageSize = 1024 * 1024 * 400
+
 // A unique ID provided to the output stream of each plugin.  This allows the output of the plugin
 // to be streamed to the display, while still allowing that output to be sent a small piece at a
 // time.
@@ -149,10 +152,13 @@ func newPlugin(ctx *Context, bin string, prefix string, args []string) (*plugin,
 	plug.stdoutDone = stdoutDone
 	go runtrace(plug.Stdout, false, stdoutDone)
 
+	// We want to increase the default message size as per pulumi/pulumi#2319
+	messageSizeOpts := grpc.WithDefaultCallOptions(grpc.MaxCallRecvMsgSize(pluginRPCMaxMessageSize))
+
 	// Now that we have the port, go ahead and create a gRPC client connection to it.
 	conn, err := grpc.Dial("127.0.0.1:"+port, grpc.WithInsecure(), grpc.WithUnaryInterceptor(
 		rpcutil.OpenTracingClientInterceptor(),
-	))
+	), messageSizeOpts)
 	if err != nil {
 		return nil, errors.Wrapf(err, "could not dial plugin [%v] over RPC", bin)
 	}