[Feature] add a cache to the FetchResult codepath to avoid API calls (#…

…45)

lint: fix `ConnectionId`

Fix CI for current master (#47)

* lint: fix `ConnectionId`

* Test fixes for previous change (`41c90a09`)

* nit: tweaks to dsn-test

Co-authored-by: Agam Brahma <agam@sigmacomputing.com>

fix var inits (#46)

connection.go

@@ -69,6 +69,7 @@ type snowflakeConn struct {
 	SQLState        string
 	telemetry       *snowflakeTelemetry
 	internal        InternalClient
+	execRespCache   *execRespCache
 }
 
 var (
@@ -228,6 +229,9 @@ func (sc *snowflakeConn) cleanup() {
 	}
 	sc.rest = nil
 	sc.cfg = nil
+
+	releaseExecRespCache(sc.execRespCache)
+	sc.execRespCache = nil
 }
 
 func (sc *snowflakeConn) Close() (err error) {
@@ -504,6 +508,12 @@ func buildSnowflakeConn(ctx context.Context, config Config) (*snowflakeConn, err
 	} else {
 		tokenAccessor = getSimpleTokenAccessor()
 	}
+	if sc.cfg.DisableTelemetry {
+		sc.telemetry = &snowflakeTelemetry{enabled: false}
+	}
+	if sc.cfg.ConnectionID != "" {
+		sc.execRespCache = acquireExecRespCache(sc.cfg.ConnectionID)
+	}
 
 	// authenticate
 	sc.rest = &snowflakeRestful{

dsn.go

@@ -12,6 +12,8 @@ import (
 	"strconv"
 	"strings"
 	"time"
+
+	"github.com/google/uuid"
 )
 
 const (
@@ -87,6 +89,9 @@ type Config struct {
 	IDToken                        string     // Internally used to cache the Id Token for external browser
 	ClientRequestMfaToken          ConfigBool // When true the MFA token is cached in the credential manager. True by default in Windows/OSX. False for Linux.
 	ClientStoreTemporaryCredential ConfigBool // When true the ID token is cached in the credential manager. True by default in Windows/OSX. False for Linux.
+	// An identifier for this Config. Used to associate multiple connection instances with
+	// a single logical sql.DB connection.
+	ConnectionID string
 }
 
 // ocspMode returns the OCSP mode in string INSECURE, FAIL_OPEN, FAIL_CLOSED
@@ -212,6 +217,10 @@ func DSN(cfg *Config) (dsn string, err error) {
 	if cfg.ClientStoreTemporaryCredential != configBoolNotSet {
 		params.Add("clientStoreTemporaryCredential", strconv.FormatBool(cfg.ClientStoreTemporaryCredential != ConfigBoolFalse))
 	}
+
+	if cfg.ConnectionID != "" {
+		params.Add("connectionId", cfg.ConnectionID)
+	}
 
 	dsn = fmt.Sprintf("%v:%v@%v:%v", url.QueryEscape(cfg.User), url.QueryEscape(cfg.Password), cfg.Host, cfg.Port)
 	if params.Encode() != "" {
@@ -437,6 +446,10 @@ func fillMissingConfigParameters(cfg *Config) error {
 		cfg.ValidateDefaultParameters = ConfigBoolTrue
 	}
 
+	if cfg.ConnectionID == "" {
+		cfg.ConnectionID = uuid.New().String()
+	}
+
 	if strings.HasSuffix(cfg.Host, defaultDomain) && len(cfg.Host) == len(defaultDomain) {
 		return &SnowflakeError{
 			Number:      ErrCodeFailedToParseHost,