Package structure refactor.

postgres/dialect.go

@@ -0,0 +1,70 @@
+package postgres
+
+import (
+	"github.com/go-jet/jet/internal/jet"
+	"strconv"
+)
+
+var Dialect = NewDialect()
+
+func NewDialect() jet.Dialect {
+
+	dialectParams := jet.DialectParams{
+		Name:                "PostgreSQL",
+		PackageName:         "postgres",
+		CastOverride:        castFunc,
+		AliasQuoteChar:      '"',
+		IdentifierQuoteChar: '"',
+		ArgumentPlaceholder: func(ord int) string {
+			return "$" + strconv.Itoa(ord)
+		},
+		UpdateAssigment:   postgresUpdateAssigment,
+		SupportsReturning: true,
+	}
+
+	return jet.NewDialect(dialectParams)
+}
+
+func castFunc(expression jet.Expression, castType string) jet.SerializeFunc {
+	return func(statement jet.StatementType, out *jet.SqlBuilder, options ...jet.SerializeOption) error {
+		if err := jet.Serialize(expression, statement, out, options...); err != nil {
+			return err
+		}
+		out.WriteString("::" + castType)
+		return nil
+	}
+}
+
+func postgresUpdateAssigment(columns []jet.IColumn, values []jet.Clause, out *jet.SqlBuilder) (err error) {
+	if len(columns) > 1 {
+		out.WriteString("(")
+	}
+
+	err = jet.SerializeColumnNames(columns, out)
+
+	if err != nil {
+		return
+	}
+
+	if len(columns) > 1 {
+		out.WriteString(")")
+	}
+
+	out.WriteString("=")
+
+	if len(values) > 1 {
+		out.WriteString("(")
+	}
+
+	err = jet.SerializeClauseList(jet.UpdateStatementType, values, out)
+
+	if err != nil {
+		return
+	}
+
+	if len(values) > 1 {
+		out.WriteString(")")
+	}
+
+	return
+}