Make public interfaces implementable

currently private interface `token` directly or indirectly present in
lot's of interfaces and therefore makes them unimplementable:
`SelectedHost`, `ExecutableQuery`, `HostSelectionPolicy`, `NextHost`

To fix it we need to make all parts of interfaces be public

connectionpool.go

@@ -329,7 +329,7 @@ func newHostConnPool(session *Session, host *HostInfo, port, size int,
 }
 
 // Pick a connection from this connection pool for the given query.
-func (pool *hostConnPool) Pick(token token, keyspace string, table string) *Conn {
+func (pool *hostConnPool) Pick(token Token, keyspace string, table string) *Conn {
 	pool.mu.RLock()
 	defer pool.mu.RUnlock()
 

connpicker.go

@@ -7,7 +7,7 @@ import (
 )
 
 type ConnPicker interface {
-	Pick(token, string, string) *Conn
+	Pick(Token, string, string) *Conn
 	Put(*Conn)
 	Remove(conn *Conn)
 	InFlight() int
@@ -71,7 +71,7 @@ func (p *defaultConnPicker) Size() (int, int) {
 	return size, p.size - size
 }
 
-func (p *defaultConnPicker) Pick(token, string, string) *Conn {
+func (p *defaultConnPicker) Pick(Token, string, string) *Conn {
 	pos := int(atomic.AddUint32(&p.pos, 1) - 1)
 	size := len(p.conns)
 
@@ -110,7 +110,7 @@ func (*defaultConnPicker) NextShard() (shardID, nrShards int) {
 // to the point where we have first connection.
 type nopConnPicker struct{}
 
-func (nopConnPicker) Pick(token, string, string) *Conn {
+func (nopConnPicker) Pick(Token, string, string) *Conn {
 	return nil
 }
 

host_source.go

@@ -435,10 +435,10 @@ func (h *HostInfo) Hostname() string {
 }
 
 func (h *HostInfo) ConnectAddressAndPort() string {
-        h.mu.Lock()
-        defer h.mu.Unlock()
-        addr, _ := h.connectAddressLocked()
-        return net.JoinHostPort(addr.String(), strconv.Itoa(h.port))
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	addr, _ := h.connectAddressLocked()
+	return net.JoinHostPort(addr.String(), strconv.Itoa(h.port))
 }
 
 func (h *HostInfo) String() string {
@@ -596,7 +596,7 @@ func addTabletToTabletsList(tablets []*TabletInfo, tablet *TabletInfo) []*Tablet
 }
 
 // Search for place in tablets table for token starting from index l to index r
-func findTabletForToken(tablets []*TabletInfo, token token, l int, r int) *TabletInfo {
+func findTabletForToken(tablets []*TabletInfo, token Token, l int, r int) *TabletInfo {
 	for l < r {
 		var m int
 		if r*l > 0 {

metadata_scylla.go

@@ -244,7 +244,7 @@ type schemaDescriber struct {
 	session *Session
 	mu      sync.Mutex
 
-	cache        map[string]*KeyspaceMetadata
+	cache map[string]*KeyspaceMetadata
 
 	// Experimental, this interface and use may change
 	tabletsCache *TabletsMetadata

policies.go

@@ -323,20 +323,20 @@ type HostSelectionPolicy interface {
 // selection policy.
 type SelectedHost interface {
 	Info() *HostInfo
-	Token() token
+	Token() Token
 	Mark(error)
 }
 
 type selectedHost struct {
 	info  *HostInfo
-	token token
+	token Token
 }
 
 func (host selectedHost) Info() *HostInfo {
 	return host.info
 }
 
-func (host selectedHost) Token() token {
+func (host selectedHost) Token() Token {
 	return host.token
 }
 
@@ -928,7 +928,7 @@ func (host selectedHostPoolHost) Info() *HostInfo {
 	return host.info
 }
 
-func (host selectedHostPoolHost) Token() token {
+func (host selectedHostPoolHost) Token() Token {
 	return nil
 }
 

scylla.go

@@ -353,7 +353,7 @@ func newScyllaConnPicker(conn *Conn) *scyllaConnPicker {
 	}
 }
 
-func (p *scyllaConnPicker) Pick(t token, keyspace string, table string) *Conn {
+func (p *scyllaConnPicker) Pick(t Token, keyspace string, table string) *Conn {
 	if len(p.conns) == 0 {
 		return nil
 	}
@@ -378,13 +378,13 @@ func (p *scyllaConnPicker) Pick(t token, keyspace string, table string) *Conn {
 		conn.mu.Lock()
 		if conn.tabletsRoutingV1 {
 			tablets := conn.session.getTablets()
-	
+
 			// Search for tablets with Keyspace and Table from the Query
 			l, r := findTablets(tablets, keyspace, table)
-	
+
 			if l != -1 {
 				tablet := findTabletForToken(tablets, mmt, l, r)
-	
+
 				for _, replica := range tablet.replicas {
 					if replica.hostId.String() == p.hostId {
 						idx = replica.shardId
@@ -396,7 +396,7 @@ func (p *scyllaConnPicker) Pick(t token, keyspace string, table string) *Conn {
 
 		break
 	}
-	
+
 	if idx == -1 {
 		idx = p.shardOf(mmt)
 	}
@@ -415,15 +415,15 @@ func (p *scyllaConnPicker) maybeReplaceWithLessBusyConnection(c *Conn) *Conn {
 		return c
 	}
 	alternative := p.leastBusyConn()
-	if alternative == nil || alternative.AvailableStreams() * 120 > c.AvailableStreams() * 100 {
+	if alternative == nil || alternative.AvailableStreams()*120 > c.AvailableStreams()*100 {
 		return c
 	} else {
 		return alternative
 	}
 }
 
 func isHeavyLoaded(c *Conn) bool {
-    return c.streams.NumStreams / 2 > c.AvailableStreams();
+	return c.streams.NumStreams/2 > c.AvailableStreams()
 }
 
 func (p *scyllaConnPicker) leastBusyConn() *Conn {

scylla_cdc.go

@@ -30,7 +30,7 @@ func (p scyllaCDCPartitioner) Name() string {
 	return scyllaCDCPartitionerName
 }
 
-func (p scyllaCDCPartitioner) Hash(partitionKey []byte) token {
+func (p scyllaCDCPartitioner) Hash(partitionKey []byte) Token {
 	if len(partitionKey) < 8 {
 		// The key is too short to extract any sensible token,
 		// so return the min token instead
@@ -68,7 +68,7 @@ func (p scyllaCDCPartitioner) Hash(partitionKey []byte) token {
 	return int64Token(upperQword)
 }
 
-func (p scyllaCDCPartitioner) ParseString(str string) token {
+func (p scyllaCDCPartitioner) ParseString(str string) Token {
 	return parseInt64Token(str)
 }
 

scylla_test.go

@@ -24,7 +24,7 @@ func TestScyllaConnPickerPickNilToken(t *testing.T) {
 		s.conns = []*Conn{{
 			streams: streams.New(protoVersion4),
 		}}
-		if s.Pick(token(nil), "", "") != s.conns[0] {
+		if s.Pick(Token(nil), "", "") != s.conns[0] {
 			t.Fatal("expected connection")
 		}
 	})
@@ -33,7 +33,7 @@ func TestScyllaConnPickerPickNilToken(t *testing.T) {
 		s.conns = []*Conn{{
 			streams: streams.New(protoVersion4),
 		}}
-		if s.Pick(token(nil), "", "") != s.conns[0] {
+		if s.Pick(Token(nil), "", "") != s.conns[0] {
 			t.Fatal("expected connection")
 		}
 	})
@@ -42,20 +42,20 @@ func TestScyllaConnPickerPickNilToken(t *testing.T) {
 		s.conns = []*Conn{nil, {
 			streams: streams.New(protoVersion4),
 		}}
-		if s.Pick(token(nil), "", "") != s.conns[1] {
+		if s.Pick(Token(nil), "", "") != s.conns[1] {
 			t.Fatal("expected connection")
 		}
-		if s.Pick(token(nil), "", "") != s.conns[1] {
+		if s.Pick(Token(nil), "", "") != s.conns[1] {
 			t.Fatal("expected connection")
 		}
 	})
 
 	t.Run("multiple shards no conns", func(t *testing.T) {
 		s.conns = []*Conn{nil, nil}
-		if s.Pick(token(nil), "", "") != nil {
+		if s.Pick(Token(nil), "", "") != nil {
 			t.Fatal("expected nil")
 		}
-		if s.Pick(token(nil), "", "") != nil {
+		if s.Pick(Token(nil), "", "") != nil {
 			t.Fatal("expected nil")
 		}
 	})
@@ -163,7 +163,7 @@ func TestScyllaRandomConnPIcker(t *testing.T) {
 			conns:     []*Conn{nil, mockConn(1)},
 		}
 
-		if s.Pick(token(nil), "", "") == nil {
+		if s.Pick(Token(nil), "", "") == nil {
 			t.Fatal("expected connection")
 		}
 	})
@@ -187,7 +187,7 @@ func TestScyllaRandomConnPIcker(t *testing.T) {
 				defer wg.Done()
 				for i := 0; i < 3; i++ {
 					select {
-					case connCh <- s.Pick(token(nil), "", ""):
+					case connCh <- s.Pick(Token(nil), "", ""):
 					case <-ctx.Done():
 					}
 				}

session.go

@@ -2171,10 +2171,10 @@ type routingKeyInfoLRU struct {
 }
 
 type routingKeyInfo struct {
-	indexes  []int
-	types    []TypeInfo
-	keyspace string
-	table    string
+	indexes     []int
+	types       []TypeInfo
+	keyspace    string
+	table       string
 	lwt         bool
 	partitioner partitioner
 }

token.go

@@ -19,14 +19,14 @@ import (
 // a token partitioner
 type partitioner interface {
 	Name() string
-	Hash([]byte) token
-	ParseString(string) token
+	Hash([]byte) Token
+	ParseString(string) Token
 }
 
-// a token
-type token interface {
+// a Token
+type Token interface {
 	fmt.Stringer
-	Less(token) bool
+	Less(Token) bool
 }
 
 // murmur3 partitioner
@@ -36,13 +36,13 @@ func (p murmur3Partitioner) Name() string {
 	return "Murmur3Partitioner"
 }
 
-func (p murmur3Partitioner) Hash(partitionKey []byte) token {
+func (p murmur3Partitioner) Hash(partitionKey []byte) Token {
 	h1 := murmur.Murmur3H1(partitionKey)
 	return int64Token(h1)
 }
 
 // murmur3 little-endian, 128-bit hash, but returns only h1
-func (p murmur3Partitioner) ParseString(str string) token {
+func (p murmur3Partitioner) ParseString(str string) Token {
 	return parseInt64Token(str)
 }
 
@@ -58,7 +58,7 @@ func (m int64Token) String() string {
 	return strconv.FormatInt(int64(m), 10)
 }
 
-func (m int64Token) Less(token token) bool {
+func (m int64Token) Less(token Token) bool {
 	return m < token.(int64Token)
 }
 
@@ -70,20 +70,20 @@ func (p orderedPartitioner) Name() string {
 	return "OrderedPartitioner"
 }
 
-func (p orderedPartitioner) Hash(partitionKey []byte) token {
+func (p orderedPartitioner) Hash(partitionKey []byte) Token {
 	// the partition key is the token
 	return orderedToken(partitionKey)
 }
 
-func (p orderedPartitioner) ParseString(str string) token {
+func (p orderedPartitioner) ParseString(str string) Token {
 	return orderedToken(str)
 }
 
 func (o orderedToken) String() string {
 	return string(o)
 }
 
-func (o orderedToken) Less(token token) bool {
+func (o orderedToken) Less(token Token) bool {
 	return o < token.(orderedToken)
 }
 
@@ -98,7 +98,7 @@ func (r randomPartitioner) Name() string {
 // 2 ** 128
 var maxHashInt, _ = new(big.Int).SetString("340282366920938463463374607431768211456", 10)
 
-func (p randomPartitioner) Hash(partitionKey []byte) token {
+func (p randomPartitioner) Hash(partitionKey []byte) Token {
 	sum := md5.Sum(partitionKey)
 	val := new(big.Int)
 	val.SetBytes(sum[:])
@@ -110,7 +110,7 @@ func (p randomPartitioner) Hash(partitionKey []byte) token {
 	return (*randomToken)(val)
 }
 
-func (p randomPartitioner) ParseString(str string) token {
+func (p randomPartitioner) ParseString(str string) Token {
 	val := new(big.Int)
 	val.SetString(str, 10)
 	return (*randomToken)(val)
@@ -120,12 +120,12 @@ func (r *randomToken) String() string {
 	return (*big.Int)(r).String()
 }
 
-func (r *randomToken) Less(token token) bool {
+func (r *randomToken) Less(token Token) bool {
 	return -1 == (*big.Int)(r).Cmp((*big.Int)(token.(*randomToken)))
 }
 
 type hostToken struct {
-	token token
+	token Token
 	host  *HostInfo
 }
 
@@ -212,7 +212,7 @@ func (t *tokenRing) String() string {
 //
 // It returns two tokens. First is token that exactly corresponds to the partition key (and could be used to
 // determine shard, for example), second token is the endToken that corresponds to the host.
-func (t *tokenRing) GetHostForPartitionKey(partitionKey []byte) (host *HostInfo, token token, endToken token) {
+func (t *tokenRing) GetHostForPartitionKey(partitionKey []byte) (host *HostInfo, token Token, endToken Token) {
 	if t == nil {
 		return nil, nil, nil
 	}
@@ -222,7 +222,7 @@ func (t *tokenRing) GetHostForPartitionKey(partitionKey []byte) (host *HostInfo,
 	return host, token, endToken
 }
 
-func (t *tokenRing) GetHostForToken(token token) (host *HostInfo, endToken token) {
+func (t *tokenRing) GetHostForToken(token Token) (host *HostInfo, endToken Token) {
 	if t == nil || len(t.tokens) == 0 {
 		return nil, nil
 	}

token_test.go

@@ -133,7 +133,7 @@ func TestRandomToken(t *testing.T) {
 type intToken int
 
 func (i intToken) String() string        { return strconv.Itoa(int(i)) }
-func (i intToken) Less(token token) bool { return i < token.(intToken) }
+func (i intToken) Less(token Token) bool { return i < token.(intToken) }
 
 // Test of the token ring implementation based on example at the start of this
 // page of documentation:

topology.go

@@ -9,7 +9,7 @@ import (
 
 type hostTokens struct {
 	// token is end (inclusive) of token range these hosts belong to
-	token token
+	token Token
 	hosts []*HostInfo
 }
 
@@ -24,7 +24,7 @@ func (h tokenRingReplicas) Less(i, j int) bool { return h[i].token.Less(h[j].tok
 func (h tokenRingReplicas) Len() int           { return len(h) }
 func (h tokenRingReplicas) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }
 
-func (h tokenRingReplicas) replicasFor(t token) *hostTokens {
+func (h tokenRingReplicas) replicasFor(t Token) *hostTokens {
 	if len(h) == 0 {
 		return nil
 	}