[BCF-3392] - ContractReaderByIDs Wrapper (#797)

* WIP

* Update ContractReaderByIDs interface method names

* Unexpose types.ContractReader in contractReaderByIDs

* Add multiple contract address support to fakeContractReader for tests

* Add GetLatestValue unit test for contractReaderByIDs

* Add GetLatestValue unit test for QueryKey

* Add BatchGetLatestValues unit test for CR by custom IdDs wrapper

* Rm ContractReaderByIDs interface and export the struct

* Change ContractReaderByIDs wrapper Unbind handling

* Improve ContractReaderByIDs wrapper err handling

* Remove mockery usage from ContractReaderByIDs tests

* lint

pkg/chainreader/contract_reader.go

@@ -0,0 +1,115 @@
+package chainreader
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"sync"
+
+	"github.com/smartcontractkit/chainlink-common/pkg/types"
+	"github.com/smartcontractkit/chainlink-common/pkg/types/query"
+	"github.com/smartcontractkit/chainlink-common/pkg/types/query/primitives"
+)
+
+var (
+	ErrNoBindings = errors.New("no bindings found")
+)
+
+// WrapContractReaderByIDs returns types.ContractReader behind ContractReaderByIDs interface.
+func WrapContractReaderByIDs(contractReader types.ContractReader) ContractReaderByIDs {
+	return ContractReaderByIDs{
+		cr: contractReader,
+	}
+}
+
+// ContractReaderByIDs wraps types.ContractReader to allow the caller to set custom contractIDs with Bind.
+type ContractReaderByIDs struct {
+	bindings sync.Map
+	cr       types.ContractReader
+}
+
+// Bind accepts a map of bound contracts where map keys are custom contractIDs which will be used by the wrapper to reference contracts.
+func (crByIds *ContractReaderByIDs) Bind(ctx context.Context, bindings map[string]types.BoundContract) error {
+	var toBind []types.BoundContract
+	for customContractID, boundContract := range bindings {
+		crByIds.bindings.Store(customContractID, boundContract)
+		toBind = append(toBind, boundContract)
+	}
+	return crByIds.cr.Bind(ctx, toBind)
+}
+
+func (crByIds *ContractReaderByIDs) Unbind(ctx context.Context, bindings map[string]types.BoundContract) error {
+	var toUnbind []types.BoundContract
+	for _, boundContract := range bindings {
+		toUnbind = append(toUnbind, boundContract)
+	}
+
+	err := crByIds.cr.Unbind(ctx, toUnbind)
+	if err == nil {
+		for customContractID := range bindings {
+			crByIds.bindings.Delete(customContractID)
+		}
+	}
+
+	return err
+}
+
+func (crByIds *ContractReaderByIDs) GetLatestValue(ctx context.Context, contractID, readName string, confidenceLevel primitives.ConfidenceLevel, params, returnVal any) error {
+	boundContract, err := crByIds.getBoundContract(contractID)
+	if err != nil {
+		return err
+	}
+
+	return crByIds.cr.GetLatestValue(ctx, boundContract.ReadIdentifier(readName), confidenceLevel, params, returnVal)
+}
+
+func (crByIds *ContractReaderByIDs) QueryKey(ctx context.Context, contractID string, filter query.KeyFilter, limitAndSort query.LimitAndSort, sequenceDataType any) ([]types.Sequence, error) {
+	boundContract, err := crByIds.getBoundContract(contractID)
+	if err != nil {
+		return nil, err
+	}
+
+	return crByIds.cr.QueryKey(ctx, boundContract, filter, limitAndSort, sequenceDataType)
+}
+
+type BatchGetLatestValuesRequestByCustomID map[string]types.ContractBatch
+type BatchGetLatestValuesResultByCustomID map[string]types.ContractBatchResults
+
+func (crByIds *ContractReaderByIDs) BatchGetLatestValues(ctx context.Context, request BatchGetLatestValuesRequestByCustomID) (BatchGetLatestValuesResultByCustomID, error) {
+	bcToID := make(map[string]string)
+	req := make(types.BatchGetLatestValuesRequest)
+	for contractID, batch := range request {
+		boundContract, err := crByIds.getBoundContract(contractID)
+		if err != nil {
+			return nil, err
+		}
+
+		req[boundContract] = batch
+		bcToID[boundContract.String()] = contractID
+	}
+
+	res, err := crByIds.cr.BatchGetLatestValues(ctx, req)
+	if err != nil {
+		return nil, err
+	}
+
+	wrappedRes := make(BatchGetLatestValuesResultByCustomID)
+	for bc, batchResp := range res {
+		wrappedRes[bcToID[bc.String()]] = batchResp
+	}
+
+	return wrappedRes, nil
+}
+
+func (crByIds *ContractReaderByIDs) getBoundContract(contractID string) (types.BoundContract, error) {
+	binding, ok := crByIds.bindings.Load(contractID)
+	if !ok {
+		return types.BoundContract{}, fmt.Errorf("%w for contractID: %s", ErrNoBindings, contractID)
+	}
+
+	boundContract, ok := binding.(types.BoundContract)
+	if !ok {
+		return types.BoundContract{}, fmt.Errorf("binding found for contractID %s, but is malformed", contractID)
+	}
+	return boundContract, nil
+}