[FAB-9574] overridable Endpoint configs

	The SDK user can now add their own implementation
	of EndpointConfig sub interfaces implementing
	each function individually by passing them to
	the WithConfigEndpoint() function as a variadic
	argument ie: fabsdk.withConfigEndpoint(i1, i2, i3, ...)
	where i1, i2, i3... each implement one (or more) of
	fab.EndpointConfig functions.

Change-Id: Iec1dc7287734d1fbc089e86f7fa533fed186580c
Signed-off-by: Baha Shaaban <baha.shaaban@securekey.com>

pkg/fab/chconfig/chconfig.go

@@ -216,7 +216,7 @@ func (c *ChannelConfig) resolveOptsFromConfig(ctx context.Client) error {
 	//If missing from opts, check config and update opts from config
 	chSdkCfg, err := ctx.EndpointConfig().ChannelConfig(c.channelID)
 	if err != nil {
-		//ver rare, but return default in case of error
+		//very rare, but return default in case of error
 		return err
 	}
 

pkg/fab/mocks/mockconfig.go

@@ -111,11 +111,6 @@ func (c *MockConfig) CAClientCert(org string) ([]byte, error) {
 	return nil, nil
 }
 
-//TimeoutOrDefault not implemented
-func (c *MockConfig) TimeoutOrDefault(arg fab.TimeoutType) time.Duration {
-	return time.Second * 5
-}
-
 //Timeout not implemented
 func (c *MockConfig) Timeout(arg fab.TimeoutType) time.Duration {
 	return time.Second * 10

pkg/fab/opts.go

@@ -0,0 +1,215 @@
+/*
+Copyright SecureKey Technologies Inc. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package fab
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"time"
+
+	"github.com/hyperledger/fabric-sdk-go/pkg/common/providers/fab"
+	"github.com/pkg/errors"
+)
+
+// EndpointConfigOptions represents EndpointConfig interface with overridable interface functions
+// if a function is not overridden, the default EndpointConfig implementation will be used.
+type EndpointConfigOptions struct {
+	timeout
+	mspID
+	peerMSPID
+	orderersConfig
+	ordererConfig
+	peersConfig
+	peerConfig
+	networkConfig
+	networkPeers
+	channelConfig
+	channelPeers
+	channelOrderers
+	tlsCACertPool
+	eventServiceType
+	tlsClientCerts
+	cryptoConfigPath
+}
+
+type applier func()
+type predicate func() bool
+type setter struct{ isSet bool }
+
+// timeout interface allows to uniquely override EndpointConfig interface's Timeout() function
+type timeout interface {
+	Timeout(fab.TimeoutType) time.Duration
+}
+
+// mspID interface allows to uniquely override EndpointConfig interface's MSPID() function
+type mspID interface {
+	MSPID(org string) (string, error)
+}
+
+// peerMSPID interface allows to uniquely override EndpointConfig interface's PeerMSPID() function
+type peerMSPID interface {
+	PeerMSPID(name string) (string, error)
+}
+
+// orderersConfig interface allows to uniquely override EndpointConfig interface's OrderersConfig() function
+type orderersConfig interface {
+	OrderersConfig() ([]fab.OrdererConfig, error)
+}
+
+// ordererConfig interface allows to uniquely override EndpointConfig interface's OrdererConfig() function
+type ordererConfig interface {
+	OrdererConfig(name string) (*fab.OrdererConfig, error)
+}
+
+// peersConfig interface allows to uniquely override EndpointConfig interface's PeersConfig() function
+type peersConfig interface {
+	PeersConfig(org string) ([]fab.PeerConfig, error)
+}
+
+// peerConfig interface allows to uniquely override EndpointConfig interface's PeerConfig() function
+type peerConfig interface {
+	PeerConfig(nameOrURL string) (*fab.PeerConfig, error)
+}
+
+// networkConfig interface allows to uniquely override EndpointConfig interface's NetworkConfig() function
+type networkConfig interface {
+	NetworkConfig() (*fab.NetworkConfig, error)
+}
+
+// networkPeers interface allows to uniquely override EndpointConfig interface's NetworkPeers() function
+type networkPeers interface {
+	NetworkPeers() ([]fab.NetworkPeer, error)
+}
+
+// channelConfig interface allows to uniquely override EndpointConfig interface's ChannelConfig() function
+type channelConfig interface {
+	ChannelConfig(name string) (*fab.ChannelNetworkConfig, error)
+}
+
+// channelPeers interface allows to uniquely override EndpointConfig interface's ChannelPeers() function
+type channelPeers interface {
+	ChannelPeers(name string) ([]fab.ChannelPeer, error)
+}
+
+// channelOrderers interface allows to uniquely override EndpointConfig interface's ChannelOrderers() function
+type channelOrderers interface {
+	ChannelOrderers(name string) ([]fab.OrdererConfig, error)
+}
+
+// tlsCACertPool interface allows to uniquely override EndpointConfig interface's TLSCACertPool() function
+type tlsCACertPool interface {
+	TLSCACertPool(certConfig ...*x509.Certificate) *x509.CertPool
+}
+
+// eventServiceType interface allows to uniquely override EndpointConfig interface's EventServiceType() function
+type eventServiceType interface {
+	EventServiceType() fab.EventServiceType
+}
+
+// tlsClientCerts interface allows to uniquely override EndpointConfig interface's TLSClientCerts() function
+type tlsClientCerts interface {
+	TLSClientCerts() ([]tls.Certificate, error)
+}
+
+// cryptoConfigPath interface allows to uniquely override EndpointConfig interface's CryptoConfigPath() function
+type cryptoConfigPath interface {
+	CryptoConfigPath() string
+}
+
+// BuildConfigEndpointFromOptions will return an EndpointConfig instance pre-built with Optional interfaces
+// provided in fabsdk's WithEndpointConfig(opts...) call
+func BuildConfigEndpointFromOptions(opts ...interface{}) (fab.EndpointConfig, error) {
+	// build a new EndpointConfig with overridden function implementations
+	c := &EndpointConfigOptions{}
+	for i, option := range opts {
+		logger.Debugf("option %d: %#v", i, option)
+		err := setEndpointConfigWithOptionInterface(c, option)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return c, nil
+}
+
+// UpdateMissingOptsWithDefaultConfig will verify if any functions of the EndpointConfig were not updated with fabsdk's
+// WithConfigEndpoint(opts...) call, then use default EndpointConfig interface for these functions instead
+func UpdateMissingOptsWithDefaultConfig(c *EndpointConfigOptions, d fab.EndpointConfig) fab.EndpointConfig {
+	s := &setter{}
+
+	s.set(c.timeout, nil, func() { c.timeout = d })
+	s.set(c.mspID, nil, func() { c.mspID = d })
+	s.set(c.peerMSPID, nil, func() { c.peerMSPID = d })
+	s.set(c.orderersConfig, nil, func() { c.orderersConfig = d })
+	s.set(c.ordererConfig, nil, func() { c.ordererConfig = d })
+	s.set(c.peersConfig, nil, func() { c.peersConfig = d })
+	s.set(c.peerConfig, nil, func() { c.peerConfig = d })
+	s.set(c.networkConfig, nil, func() { c.networkConfig = d })
+	s.set(c.networkPeers, nil, func() { c.networkPeers = d })
+	s.set(c.channelConfig, nil, func() { c.channelConfig = d })
+	s.set(c.channelPeers, nil, func() { c.channelPeers = d })
+	s.set(c.channelOrderers, nil, func() { c.channelOrderers = d })
+	s.set(c.tlsCACertPool, nil, func() { c.tlsCACertPool = d })
+	s.set(c.eventServiceType, nil, func() { c.eventServiceType = d })
+	s.set(c.tlsClientCerts, nil, func() { c.tlsClientCerts = d })
+	s.set(c.cryptoConfigPath, nil, func() { c.cryptoConfigPath = d })
+
+	return c
+}
+
+// IsEndpointConfigFullyOverridden will return true if all of the argument's sub interfaces is not nil
+// (ie EndpointConfig interface not fully overridden)
+func IsEndpointConfigFullyOverridden(c *EndpointConfigOptions) bool {
+	return !anyNil(c.timeout, c.mspID, c.peerMSPID, c.orderersConfig, c.ordererConfig, c.peersConfig, c.peerConfig, c.networkConfig,
+		c.networkPeers, c.channelConfig, c.channelPeers, c.channelOrderers, c.tlsCACertPool, c.eventServiceType, c.tlsClientCerts, c.cryptoConfigPath)
+}
+
+// will override EndpointConfig interface with functions provided by o (option)
+func setEndpointConfigWithOptionInterface(c *EndpointConfigOptions, o interface{}) error {
+	s := &setter{}
+
+	s.set(c.timeout, func() bool { _, ok := o.(timeout); return ok }, func() { c.timeout = o.(timeout) })
+	s.set(c.mspID, func() bool { _, ok := o.(mspID); return ok }, func() { c.mspID = o.(mspID) })
+	s.set(c.peerMSPID, func() bool { _, ok := o.(peerMSPID); return ok }, func() { c.peerMSPID = o.(peerMSPID) })
+	s.set(c.orderersConfig, func() bool { _, ok := o.(orderersConfig); return ok }, func() { c.orderersConfig = o.(orderersConfig) })
+	s.set(c.ordererConfig, func() bool { _, ok := o.(ordererConfig); return ok }, func() { c.ordererConfig = o.(ordererConfig) })
+	s.set(c.peersConfig, func() bool { _, ok := o.(peersConfig); return ok }, func() { c.peersConfig = o.(peersConfig) })
+	s.set(c.peerConfig, func() bool { _, ok := o.(peerConfig); return ok }, func() { c.peerConfig = o.(peerConfig) })
+	s.set(c.networkConfig, func() bool { _, ok := o.(networkConfig); return ok }, func() { c.networkConfig = o.(networkConfig) })
+	s.set(c.networkPeers, func() bool { _, ok := o.(networkPeers); return ok }, func() { c.networkPeers = o.(networkPeers) })
+	s.set(c.channelConfig, func() bool { _, ok := o.(channelConfig); return ok }, func() { c.channelConfig = o.(channelConfig) })
+	s.set(c.channelPeers, func() bool { _, ok := o.(channelPeers); return ok }, func() { c.channelPeers = o.(channelPeers) })
+	s.set(c.channelOrderers, func() bool { _, ok := o.(channelOrderers); return ok }, func() { c.channelOrderers = o.(channelOrderers) })
+	s.set(c.tlsCACertPool, func() bool { _, ok := o.(tlsCACertPool); return ok }, func() { c.tlsCACertPool = o.(tlsCACertPool) })
+	s.set(c.eventServiceType, func() bool { _, ok := o.(eventServiceType); return ok }, func() { c.eventServiceType = o.(eventServiceType) })
+	s.set(c.tlsClientCerts, func() bool { _, ok := o.(tlsClientCerts); return ok }, func() { c.tlsClientCerts = o.(tlsClientCerts) })
+	s.set(c.cryptoConfigPath, func() bool { _, ok := o.(cryptoConfigPath); return ok }, func() { c.cryptoConfigPath = o.(cryptoConfigPath) })
+
+	if !s.isSet {
+		return errors.Errorf("option %#v is not a sub interface of EndpointConfig, at least one of its functions must be implemented.", o)
+	}
+
+	return nil
+}
+
+// needed to avoid meta-linter errors (too many if conditions)
+func (o *setter) set(current interface{}, check predicate, apply applier) {
+	if current == nil && (check == nil || check()) {
+		apply()
+		o.isSet = true
+	}
+}
+
+// will verify if any of objs element is nil, also needed to avoid meta-linter errors
+func anyNil(objs ...interface{}) bool {
+	for _, p := range objs {
+		if p == nil {
+			return true
+		}
+	}
+	return false
+}