Introduce CCVProvider interface.

integration/pkg/constructors/committee_verifier.go

@@ -18,7 +18,6 @@ import (
 	"github.com/smartcontractkit/chainlink-ccv/verifier/pkg/monitoring"
 	"github.com/smartcontractkit/chainlink-common/pkg/beholder"
 	"github.com/smartcontractkit/chainlink-common/pkg/logger"
-	"github.com/smartcontractkit/chainlink-evm/pkg/chains/legacyevm"
 )
 
 // NewVerificationCoordinator starts the Committee Verifier with evm chains.
@@ -28,7 +27,7 @@ func NewVerificationCoordinator(
 	cfg verifier.Config,
 	signingAddress protocol.UnknownAddress,
 	signer verifier.MessageSigner,
-	relayers map[protocol.ChainSelector]legacyevm.Chain,
+	providers map[protocol.ChainSelector]CCVProvider,
 ) (*verifier.Coordinator, error) {
 	if err := cfg.Validate(); err != nil {
 		lggr.Errorw("Invalid CCV verifier configuration.", "error", err)
@@ -60,7 +59,7 @@ func NewVerificationCoordinator(
 	sourceReaders := make(map[protocol.ChainSelector]verifier.SourceReader)
 	sourceConfigs := make(map[protocol.ChainSelector]verifier.SourceConfig)
 	headTrackers := make(map[protocol.ChainSelector]chainaccess.HeadTracker)
-	for sel, chain := range relayers {
+	for sel, chain := range providers {
 		if _, ok := onRampAddrs[sel]; !ok {
 			lggr.Warnw("No onramp address for chain, skipping.", "chainID", sel)
 			continue

integration/pkg/constructors/executor.go

@@ -16,7 +16,6 @@ import (
 	"github.com/smartcontractkit/chainlink-ccv/protocol"
 	"github.com/smartcontractkit/chainlink-common/pkg/beholder"
 	"github.com/smartcontractkit/chainlink-common/pkg/logger"
-	"github.com/smartcontractkit/chainlink-evm/pkg/chains/legacyevm"
 	"github.com/smartcontractkit/chainlink-evm/pkg/keys"
 
 	x "github.com/smartcontractkit/chainlink-ccv/executor/pkg/executor"
@@ -26,8 +25,8 @@ import (
 func NewExecutorCoordinator(
 	lggr logger.Logger,
 	cfg executor.Configuration,
-	// TODO: all these are EVM specific, shouldn't be.
-	relayers map[protocol.ChainSelector]legacyevm.Chain,
+	providers map[protocol.ChainSelector]CCVProvider,
+	// TODO: move to CCV provider. Keys are not part of the keystore, so a container object is needed.
 	keys map[protocol.ChainSelector]keys.RoundRobin,
 	fromAddresses map[protocol.ChainSelector][]common.Address,
 ) (*executor.Coordinator, error) {
@@ -39,7 +38,7 @@ func NewExecutorCoordinator(
 
 	transmitters := make(map[protocol.ChainSelector]executor.ContractTransmitter)
 	destReaders := make(map[protocol.ChainSelector]executor.DestinationReader)
-	for sel, chain := range relayers {
+	for sel, chain := range providers {
 		if _, ok := offRampAddresses[sel]; !ok {
 			lggr.Warnw("No offramp configured for chain, skipping.", "chainID", sel)
 			continue

integration/pkg/constructors/provider.go

@@ -0,0 +1,28 @@
+package constructors
+
+import (
+	"github.com/smartcontractkit/chainlink-evm/pkg/client"
+	"github.com/smartcontractkit/chainlink-evm/pkg/heads"
+	"github.com/smartcontractkit/chainlink-evm/pkg/txmgr"
+)
+
+// CCVProvider is a work in progress! It will eventually become the chain agnostic interface implemented
+// by all chain families to support the Committee Verifier and Executor services. For now it reflects
+// the EVM-Centric nature of the initial implementation and is a simple downcast of the legacyevm.Chain
+// object.
+//
+// Note: many of the  chainlink-evm objects used here already have a generic interface in the
+// chainlink-frameworks library. The way generics are used prevents us from using them in a polymorphic way.
+// This means some sort of adapter will be required for each chain type we want to support.
+// Until that adapter interface exists, we only support EVM.
+//
+// Next steps:
+// - Identify the full set of functions required by client.Client, heads.Tracker and txmg.TxManager
+// - Redefine those functions in this interface, using protocol types where possible.
+// - Create an adapter layer for legacyevm.Chain that implements this interface.
+// - Define a LOOPP client for this interface.
+type CCVProvider interface {
+	Client() client.Client      // verifier, executor
+	HeadTracker() heads.Tracker // verifier
+	TxManager() txmgr.TxManager // executor
+}