Rpcapi fix - requires Eth namespace (#845)

* update join_network docs

* add eth as default in apis

* update changelog

CHANGELOG.md

@@ -35,6 +35,11 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 # Changelog
 
+## Unreleased
+
+### API Breaking
+* (eth) [\#845](https://github.com/cosmos/ethermint/pull/845) The `eth` namespace must be included in the list of API's as default to run the rpc server without error.
+
 ## [v0.4.1] - 2021-03-01
 
 ### API Breaking

rpc/apis.go

@@ -34,6 +34,23 @@ func GetAPIs(clientCtx context.CLIContext, selectedApis []string, keys ...ethsec
 
 	var apis []rpc.API
 
+	apis = append(apis,
+		rpc.API{
+			Namespace: EthNamespace,
+			Version:   apiVersion,
+			Service:   ethAPI,
+			Public:    true,
+		},
+	)
+	apis = append(apis,
+		rpc.API{
+			Namespace: EthNamespace,
+			Version:   apiVersion,
+			Service:   filters.NewAPI(clientCtx, backend),
+			Public:    true,
+		},
+	)
+
 	for _, api := range selectedApis {
 		switch api {
 		case Web3Namespace:
@@ -45,23 +62,6 @@ func GetAPIs(clientCtx context.CLIContext, selectedApis []string, keys ...ethsec
 					Public:    true,
 				},
 			)
-		case EthNamespace:
-			apis = append(apis,
-				rpc.API{
-					Namespace: EthNamespace,
-					Version:   apiVersion,
-					Service:   ethAPI,
-					Public:    true,
-				},
-			)
-			apis = append(apis,
-				rpc.API{
-					Namespace: EthNamespace,
-					Version:   apiVersion,
-					Service:   filters.NewAPI(clientCtx, backend),
-					Public:    true,
-				},
-			)
 		case PersonalNamespace:
 			apis = append(apis,
 				rpc.API{