Guess connection if none supplied.

CHANGELOG.md

@@ -1,5 +1,6 @@
 1.19.1:
   - add the ability to import keystores to ethdo wallets
+  - use defaults to connect to beacon nodes if no explicit connection defined
 
 1.19.0:
   - add "epoch summary"

README.md

@@ -11,6 +11,7 @@ A command-line tool for managing common tasks in Ethereum 2.
   - [Binaries](#binaries)
   - [Docker](#docker)
   - [Source](#source)
+- [Setting up](#setting-up)
 - [Usage](#usage)
 - [Maintainers](#maintainers)
 - [Contribute](#contribute)
@@ -61,13 +62,37 @@ docker run --network=host ethdo chain status
 
 Alternatively, if the beacon node is running in a separate docker container a shared network can be created with `docker network create eth2` and accessed by adding `--network=eth2` added to both the beacon node and `ethdo` containers.
 
+## Setting up
+
+`ethdo` needs a connection to a beacon node for many of its features.  `ethdo` can connect to any beacon node that fully supports the [standard REST API](https://ethereum.github.io/beacon-APIs/).  The following changes are required to beacon nodes to make this available.
+
+### Lighthouse
+Lighthouse disables the REST API by default.  To enable it, the beacon node must be started with the `--http` parameter.  If you want to access the REST API from a remote server then you should also look to change the `--http-address` and `--http-allow-origin` options as per the Lighthouse documentation.
+
+The default port for the REST API is 5052, which can be changed with the `--http-port` parameter.
+
+### Nimbus
+Nimbus disables the REST API by default.  To enable it, the beacon node must be started with the `--rest` parameter.  If you want to access the REST API from a remote server then you should also look to change the `--rest-address` and `--rest-allow-origin` options as per the Nimbus documentation.
+
+The default port for the REST API is 5052, which can be changed with the `--rest-port` parameter.
+
+### Prysm
+Prysm enables the REST API by default.  You will need to add the parameter `--grpc-max-msg-size 268435456` to be obtain to obtain large sets of information such as the list of current validators.  If you want to access the REST API from a remote server then you should also look to change the `--grpc-gateway-host` and `--grpc-gateway-corsdomain` options as per the Prysm documentation.
+
+The default port for the REST API is 3500, which can be changed with the `--grpc-gateway-port` parameter.
+
+### Teku
+Teku disables the REST API by default.  To enable it, the beacon node must be started with the `--rest-api-enabled` parameter.  If you want to access the REST API from a remote server then you should also look to change the `--rest-api-interface`, `--rest-api-host-allowlist` and `--rest-api-cors-origins` options as per the Teku documentation.
+
+The default port for the REST API is 5051, which can be changed with the `--rest-api-port` parameter.
+
 ## Usage
 
-ethdo contains a large number of features that are useful for day-to-day interactions with the Ethereum 2 blockchain.
+`ethdo` contains a large number of features that are useful for day-to-day interactions with the Ethereum 2 blockchain.
 
 ### Wallets and accounts
 
-ethdo uses the [go-eth2-wallet](https://github.com/wealdtech/go-eth2-wallet) system to provide unified access to different wallet types.  When on the filesystem the locations of the created wallets and accounts are:
+`ethdo` uses the [go-eth2-wallet](https://github.com/wealdtech/go-eth2-wallet) system to provide unified access to different wallet types.  When on the filesystem the locations of the created wallets and accounts are:
 
     - for Linux: $HOME/.config/ethereum2/wallets
     - for OSX: $HOME/Library/Application Support/ethereum2/wallets

cmd/root.go

@@ -211,7 +211,7 @@ func init() {
 	if err := viper.BindPFlag("debug", RootCmd.PersistentFlags().Lookup("debug")); err != nil {
 		panic(err)
 	}
-	RootCmd.PersistentFlags().String("connection", "http://localhost:3500", "URL to an Ethereum 2 node's RET API endpoint")
+	RootCmd.PersistentFlags().String("connection", "", "URL to an Ethereum 2 node's RET API endpoint")
 	if err := viper.BindPFlag("connection", RootCmd.PersistentFlags().Lookup("connection")); err != nil {
 		panic(err)
 	}

util/beaconnode.go

@@ -21,17 +21,41 @@ import (
 	"time"
 
 	eth2client "github.com/attestantio/go-eth2-client"
-	"github.com/attestantio/go-eth2-client/auto"
+	"github.com/attestantio/go-eth2-client/http"
 	"github.com/pkg/errors"
 	"github.com/rs/zerolog"
 )
 
+// defaultBeaconNodeAddresses are default REST endpoint addresses for beacon nodes.
+var defaultBeaconNodeAddresses = []string{
+	"localhost:5052", // Lighthouse, Nimbus
+	"localhost:5051", // Teku
+	"localhost:3500", // Prysm
+}
+
 // ConnectToBeaconNode connects to a beacon node at the given address.
 func ConnectToBeaconNode(ctx context.Context, address string, timeout time.Duration, allowInsecure bool) (eth2client.Service, error) {
 	if timeout == 0 {
 		return nil, errors.New("no timeout specified")
 	}
 
+	if address != "" {
+		// We have an explicit address; use it.
+		return connectToBeaconNode(ctx, address, timeout, allowInsecure)
+	}
+
+	// Try the defaults.
+	for _, address := range defaultBeaconNodeAddresses {
+		client, err := connectToBeaconNode(ctx, address, timeout, allowInsecure)
+		if err == nil {
+			return client, nil
+		}
+	}
+
+	return nil, errors.New("failed to connect to any beacon node")
+}
+
+func connectToBeaconNode(ctx context.Context, address string, timeout time.Duration, allowInsecure bool) (eth2client.Service, error) {
 	if !strings.HasPrefix(address, "http") {
 		address = fmt.Sprintf("http://%s", address)
 	}
@@ -49,10 +73,10 @@ func ConnectToBeaconNode(ctx context.Context, address string, timeout time.Durat
 			fmt.Println("Connections to remote beacon nodes should be secure.  This warning can be silenced with --allow-insecure-connections")
 		}
 	}
-	eth2Client, err := auto.New(ctx,
-		auto.WithLogLevel(zerolog.Disabled),
-		auto.WithAddress(address),
-		auto.WithTimeout(timeout),
+	eth2Client, err := http.New(ctx,
+		http.WithLogLevel(zerolog.Disabled),
+		http.WithAddress(address),
+		http.WithTimeout(timeout),
 	)
 	if err != nil {
 		return nil, errors.Wrap(err, "failed to connect to beacon node")