[EASI-3208] Named statement cache

go.mod

@@ -12,6 +12,7 @@ require (
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/jmoiron/sqlx v1.3.5 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/vektah/gqlparser/v2 v2.5.1 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

go.sum

@@ -11,24 +11,29 @@ github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dgryski/trifles v0.0.0-20200323201526-dd97f9abfb48/go.mod h1:if7Fbed8SFyPtHLHbg49SI7NAdJiC5WIA09pe59rfAA=
+github.com/go-sql-driver/mysql v1.6.0/go.mod h1:DCzpHaOWr8IXmIStZouvnhqoel9Qv2LBy8hT2VhHyBg=
 github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/hashicorp/golang-lru v0.5.4/go.mod h1:iADmTwqILo4mZ8BN3D2Q6+9jd8WM5uGBxy+E8yxSoD4=
+github.com/jmoiron/sqlx v1.3.5 h1:vFFPA71p1o5gAeqtEAwLU4dnX2napprKtHr7PYIcN3g=
+github.com/jmoiron/sqlx v1.3.5/go.mod h1:nRVWtLre0KfCLJvgxzCsLVMogSvQ1zNJtpYr2Ccp0mQ=
 github.com/kevinmbeaulieu/eq-go v1.0.0/go.mod h1:G3S8ajA56gKBZm4UB9AOyoOS37JO3roToPzKNM8dtdM=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/lib/pq v1.2.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
 github.com/lib/pq v1.10.6 h1:jbk+ZieJ0D7EVGJYpL9QTz7/YW6UHbmdnZWYyK5cdBs=
 github.com/lib/pq v1.10.6/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
 github.com/logrusorgru/aurora/v3 v3.0.0/go.mod h1:vsR12bk5grlLvLXAYrBsb5Oc/N+LxAlxggSjiwMnCUc=
 github.com/matryer/moq v0.2.7/go.mod h1:kITsx543GOENm48TUAQyJ9+SAvFSr7iGQXPoth/VUBk=
 github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
+github.com/mattn/go-sqlite3 v1.14.6/go.mod h1:NyWgC/yNuGj7Q9rpYnZvas74GogHl5/Z4A/KQRfk6bU=
 github.com/mitchellh/mapstructure v1.3.1/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
 github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyuac5Z2hdY=
 github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=

go/stmtcache/named_statement_cache.go

@@ -0,0 +1,79 @@
+package stmtcache
+
+import (
+	"errors"
+	"sync"
+
+	"github.com/jmoiron/sqlx"
+)
+
+// Cache is a cache of prepared statements.
+type Cache struct {
+	db                 *sqlx.DB
+	preparedStatements map[string]*sqlx.NamedStmt
+	lock               sync.RWMutex
+}
+
+// NewCache initializes a new Cache instance with the provided database.
+func NewCache(db *sqlx.DB) *Cache {
+	return &Cache{
+		db:                 db,
+		preparedStatements: make(map[string]*sqlx.NamedStmt),
+	}
+}
+
+// Get returns a prepared statement for the provided query.
+func (n *Cache) Get(query string) (*sqlx.NamedStmt, error) {
+	n.lock.RLock()
+	storedStatement, foundPreparedStatement := n.preparedStatements[query]
+	n.lock.RUnlock()
+
+	if foundPreparedStatement {
+		return storedStatement, nil
+	}
+
+	n.lock.Lock()
+	defer n.lock.Unlock()
+
+	// Check again to ensure no other goroutine prepared the statement since our previous check.
+	// We must assert this as there is a potential for a prepared statement overwrite between the
+	// first check and the write lock acquisition, however minor the chance.
+	if storedStatement, foundPreparedStatement = n.preparedStatements[query]; foundPreparedStatement {
+		return storedStatement, nil
+	}
+
+	preparedStatement, err := n.db.PrepareNamed(query)
+	if err != nil {
+		return nil, err
+	}
+
+	n.preparedStatements[query] = preparedStatement
+	return preparedStatement, nil
+}
+
+// Close releases all resources and closes all prepared statements.
+func (n *Cache) Close() error {
+	n.lock.Lock()
+	defer n.lock.Unlock()
+
+	var errs []error
+
+	for _, stmt := range n.preparedStatements {
+		if err := stmt.Close(); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	// Clear the map after attempting to close all statements
+	n.preparedStatements = make(map[string]*sqlx.NamedStmt)
+
+	if len(errs) > 0 {
+		msg := "Errors while closing prepared statements: "
+		for _, err := range errs {
+			msg += err.Error() + "; "
+		}
+		return errors.New(msg)
+	}
+
+	return nil
+}