connect to relays once per call instead of in each iteration and fail early if no connection works.

event.go

@@ -97,6 +97,16 @@ example:
 	},
 	ArgsUsage: "[relay...]",
 	Action: func(c *cli.Context) error {
+		// try to connect to the relays here
+		var relays []*nostr.Relay
+		if relayUrls := c.Args().Slice(); len(relayUrls) > 0 {
+			_, relays = connectToAllRelays(c.Context, relayUrls)
+			if len(relays) == 0 {
+				fmt.Fprintf(os.Stderr, "failed to connect to any of the given relays.\n")
+				os.Exit(3)
+			}
+		}
+
 		// gather the secret key first
 		sec := c.String("sec")
 		if c.Bool("prompt-sec") {
@@ -204,12 +214,12 @@ example:
 				}
 			}
 
-			relays := c.Args().Slice()
 			if len(relays) > 0 {
 				fmt.Println(evt.String())
-				for _, url := range relays {
-					fmt.Fprintf(os.Stderr, "publishing to %s... ", url)
-					if relay, err := nostr.RelayConnect(c.Context, url); err != nil {
+				os.Stdout.Sync()
+				for _, relay := range relays {
+					fmt.Fprintf(os.Stderr, "publishing to %s... ", relay.URL)
+					if relay, err := nostr.RelayConnect(c.Context, relay.URL); err != nil {
 						fmt.Fprintf(os.Stderr, "failed to connect: %s\n", err)
 					} else {
 						ctx, cancel := context.WithTimeout(c.Context, 10*time.Second)

helpers.go

@@ -9,6 +9,7 @@ import (
 	"os"
 	"strings"
 
+	"github.com/nbd-wtf/go-nostr"
 	"github.com/urfave/cli/v2"
 )
 
@@ -99,6 +100,21 @@ func validate32BytesHex(target string) error {
 	return nil
 }
 
+func connectToAllRelays(ctx context.Context, relayUrls []string) (*nostr.SimplePool, []*nostr.Relay) {
+	relays := make([]*nostr.Relay, 0, len(relayUrls))
+	pool := nostr.NewSimplePool(ctx)
+	for _, url := range relayUrls {
+		fmt.Fprintf(os.Stderr, "connecting to %s... ", url)
+		if relay, err := pool.EnsureRelay(url); err == nil {
+			relays = append(relays, relay)
+			fmt.Fprintf(os.Stderr, "ok.\n")
+		} else {
+			fmt.Fprintf(os.Stderr, err.Error()+"\n")
+		}
+	}
+	return pool, relays
+}
+
 func lineProcessingError(c *cli.Context, msg string, args ...any) {
 	c.Context = context.WithValue(c.Context, LINE_PROCESSING_ERROR, true)
 	fmt.Fprintf(os.Stderr, msg+"\n", args...)

req.go

@@ -3,6 +3,7 @@ package main
 import (
 	"encoding/json"
 	"fmt"
+	"os"
 	"strings"
 
 	"github.com/nbd-wtf/go-nostr"
@@ -95,6 +96,21 @@ example:
 	},
 	ArgsUsage: "[relay...]",
 	Action: func(c *cli.Context) error {
+		var pool *nostr.SimplePool
+		relayUrls := c.Args().Slice()
+		if len(relayUrls) > 0 {
+			var relays []*nostr.Relay
+			pool, relays = connectToAllRelays(c.Context, relayUrls)
+			if len(relays) == 0 {
+				fmt.Fprintf(os.Stderr, "failed to connect to any of the given relays.\n")
+				os.Exit(3)
+			}
+			relayUrls = make([]string, len(relays))
+			for i, relay := range relays {
+				relayUrls[i] = relay.URL
+			}
+		}
+
 		for stdinFilter := range getStdinLinesOrBlank() {
 			filter := nostr.Filter{}
 			if stdinFilter != "" {
@@ -155,14 +171,12 @@ example:
 				filter.Limit = limit
 			}
 
-			relays := c.Args().Slice()
-			if len(relays) > 0 {
-				pool := nostr.NewSimplePool(c.Context)
+			if len(relayUrls) > 0 {
 				fn := pool.SubManyEose
 				if c.Bool("stream") {
 					fn = pool.SubMany
 				}
-				for ie := range fn(c.Context, relays, nostr.Filters{filter}) {
+				for ie := range fn(c.Context, relayUrls, nostr.Filters{filter}) {
 					fmt.Println(ie.Event)
 				}
 			} else {