new error type

app/app.go

@@ -129,8 +129,8 @@ func RequestHandler(req *msg.Request) msg.Response {
 	// Build some error types.
 	typeErr := msg.NewProtocolError(msg.InvalidResourceType,
 		"Invalid resource type")
-	paramErr := msg.NewProtocolError(msg.InvalidResourceType,
-		"Invalid request parameter, blockNumber must be uint32.")
+	notFoundErr := msg.NewProtocolError(msg.ResourceNotFound,
+		"Resource not found.")
 
 	switch req.ResourceType {
 	case msg.ResourcePeerInfo:
@@ -143,13 +143,13 @@ func RequestHandler(req *msg.Request) msg.Response {
 			blk, err := chain.CopyBlockByIndex(blockNumber)
 			if err != nil {
 				// Bad index parameter.
-				res.Error = paramErr
+				res.Error = notFoundErr
 			} else {
 				res.Resource = blk
 			}
 		} else {
 			// No index parameter.
-			res.Error = paramErr
+			res.Error = notFoundErr
 		}
 	default:
 		// Return err by default.

msg/message.go

@@ -27,6 +27,8 @@ const (
 	// InvalidResourceType occurs when a request is received with an unknown
 	// ResourceType value.
 	InvalidResourceType = 401
+	// ResourceNotFound occurs when a node reports the requested resource missing.
+	ResourceNotFound = 404
 	// NotImplemented occurs when a message or request is received whos response
 	// requires functionality that does not yet exist.
 	NotImplemented = 501

pool/pool_test.go

@@ -102,7 +102,7 @@ func TestNextBlock(t *testing.T) {
 	}
 	b := p.NextBlock(chain, blockchain.NewWallet().Public(), 1<<18)
 	assert.NotNil(t, b)
-	assert.True(t, b.Len() < blockchain.UserBlockSize)
+	assert.True(t, b.Len() < 1<<18)
 	assert.True(t, b.Len() > 0)
 
 	// The difference is off by one thanks to cloud transaction.