rpcserver: NewAddr endpoint: check connections for all uni URLs

Move the connection check to a general location so it runs for all
tap address types, as long as the proof courier URL scheme is a universe
RPC URL scheme.

Add a flag to skip the connection check when generating tap addresses
offline.

Author: ffranr

itest/addrs_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
+	"net/url"
 	"time"
 
 	"github.com/btcsuite/btcd/btcec/v2/schnorr"
@@ -491,7 +492,12 @@ func testAddressAssetSyncer(t *harnessTest) {
 
 	thirdAsset := secondRpcAssets[2]
 	thirdGroup := thirdAsset.AssetGroup
-	v2Courier := address.RandProofCourierAddrForVersion(t.t, address.V2)
+
+	v2Courier, err := url.Parse(
+		"authmailbox+universerpc://" + t.universeServer.ListenAddr,
+	)
+	require.NoError(t.t, err)
+
 	_, err = bob.NewAddr(ctxt, &taprpc.NewAddrRequest{
 		AddressVersion:   taprpc.AddrVersion_ADDR_VERSION_V2,
 		GroupKey:         thirdGroup.TweakedGroupKey,

itest/send_test.go

@@ -1180,9 +1180,10 @@ func testSpendChangeOutputWhenProofTransferFail(t *harnessTest) {
 	// (due to the proof courier being shut down). We will generate a new
 	// address for this new transaction.
 	recvAddr, err = recvTapd.NewAddr(ctxb, &taprpc.NewAddrRequest{
-		AssetId:          genInfo.AssetId,
-		Amt:              42,
-		ProofCourierAddr: proofCourierAddr,
+		AssetId:                   genInfo.AssetId,
+		Amt:                       42,
+		ProofCourierAddr:          proofCourierAddr,
+		SkipProofCourierConnCheck: true,
 	})
 	require.NoError(t.t, err)
 	AssertAddrCreated(t.t, recvTapd, rpcAssets[0], recvAddr)

rpcserver.go

@@ -1704,40 +1704,49 @@ func (r *rpcServer) NewAddr(ctx context.Context,
 		"courier=%v, addr_version=%v, asset_version=%v", &specifier,
 		req.Amt, courierAddr, addrVersion, assetVersion)
 
-	// Addresses with version 2 must use the new authmailbox proof courier
+	// Addresses with version 2 must use the new auth mailbox proof courier
 	// type.
-	protocol := courierAddr.Scheme
 	switch {
 	case addrVersion == address.V2 &&
-		protocol == proof.UniverseRpcCourierType:
+		courierAddr.Scheme == proof.UniverseRpcCourierType:
 
 		// We assume that any proof courier running an RPC universe
 		// server will upgrade soon to support the new auth mailbox
 		// courier type, so we bump the protocol/scheme to the combined
 		// one.
 		courierAddr.Scheme = proof.AuthMailboxUniRpcCourierType
 
-		// Let's make sure the proof courier actually supports the
-		// auth mailbox courier type.
-		err := proof.CheckUniverseRpcCourierConnection(
-			ctx, proofCourierCheckTimeout, courierAddr,
-		)
-		if err != nil {
-			return nil, err
-		}
-
 	case addrVersion == address.V2 &&
-		protocol == proof.AuthMailboxUniRpcCourierType:
+		courierAddr.Scheme == proof.AuthMailboxUniRpcCourierType:
 
 		// Great, nothing to do here, this is the courier type we want.
 
-	case addrVersion == address.V2 && protocol == proof.HashmailCourierType:
+	case addrVersion == address.V2 &&
+		courierAddr.Scheme == proof.HashmailCourierType:
+
 		return nil, fmt.Errorf("%w: address version %d must use the "+
 			"'%s' proof courier type",
 			address.ErrInvalidProofCourierAddr, addrVersion,
 			proof.AuthMailboxUniRpcCourierType)
 	}
 
+	// If the courier is an (auth mailbox) universe RPC type we will check
+	// that we can connect to it.
+	connCheckScheme := courierAddr.Scheme == proof.UniverseRpcCourierType ||
+		courierAddr.Scheme == proof.AuthMailboxUniRpcCourierType
+	if !req.SkipProofCourierConnCheck && connCheckScheme {
+		rpcsLog.DebugS(ctx, "Checking connection to universe server "+
+			"RPC", "courier_addr", courierAddr.String())
+
+		err := proof.CheckUniverseRpcCourierConnection(
+			ctx, proofCourierCheckTimeout, courierAddr,
+		)
+		if err != nil {
+			return nil, fmt.Errorf("connection check failed for "+
+				"universe server RPC proof courier: %w", err)
+		}
+	}
+
 	var addr *address.AddrWithKeyInfo
 	switch {
 	// No key was specified, we'll let the address book derive them.