add bob helpers functions

v2/dbutils/bob_helpers/bob_helpers.go

@@ -4,6 +4,14 @@ import (
 	"database/sql"
 	"reflect"
 	"time"
+
+	"github.com/aarondl/opt"
+	"github.com/stephenafamo/bob"
+	"github.com/stephenafamo/bob/dialect/psql"
+	"github.com/stephenafamo/bob/dialect/psql/dialect"
+	"github.com/stephenafamo/bob/dialect/psql/sm"
+	"github.com/stephenafamo/bob/expr"
+	"github.com/stephenafamo/scan"
 )
 
 // Ptr returns a pointer to the given value.
@@ -57,3 +65,97 @@ func isZero[T any](v T) bool {
 	var zero T
 	return reflect.DeepEqual(v, zero)
 }
+
+// IncludeSubqueryAsCTE appends a subquery as a Common Table Expression (CTE)
+// to the provided query modifiers slice.
+//
+// This helper simplifies adding a named subquery (`WITH <alias> AS (...)`) to a
+// `bob`-built query, allowing you to keep query composition modular.
+//
+// Example:
+//
+//	var mods []bob.Mod[*dialect.SelectQuery]
+//	sub := []bob.Mod[*dialect.SelectQuery]{
+//		psql.From("users").Where(psql.Col("active").Eq(true)),
+//	}
+//	IncludeSubqueryAsCTE(&mods, sub, "active_users")
+//
+// Generates:
+//
+//	WITH active_users AS (
+//	    SELECT * FROM users WHERE active = true
+//	)
+//
+// Parameters:
+//   - q: pointer to the main query modifiers slice to be extended.
+//   - subQuery: slice of modifiers defining the subquery to include.
+//   - alias: name of the CTE (the identifier after WITH).
+func IncludeSubqueryAsCTE(q *[]bob.Mod[*dialect.SelectQuery], subQuery []bob.Mod[*dialect.SelectQuery], alias string) {
+	sub := psql.Select(
+		subQuery...,
+	)
+	*q = append(*q,
+		sm.With(alias).As(sub),
+	)
+}
+
+// TableWithPrefix prefixes all columns in the given ColumnsExpr with the table alias.
+// Equivalent to using `--prefix:<alias>.` in bob SQL files.
+func TableWithPrefix(alias string, col expr.ColumnsExpr) expr.ColumnsExpr {
+	return col.WithPrefix(alias + ".")
+}
+
+// TableWithPrefixAndParent prefixes all columns and sets the parent to the alias.
+// Useful for nested structs when mapping joined tables.
+func TableWithPrefixAndParent(alias string, col expr.ColumnsExpr) expr.ColumnsExpr {
+	return col.WithPrefix(alias + ".").WithParent(alias)
+}
+
+// GroupByWithParent groups by columns and sets their parent to the given alias.
+// Useful for grouping joined table columns in nested mappings.
+func GroupByWithParent(alias string, col expr.ColumnsExpr) bob.Mod[*dialect.SelectQuery] {
+	return sm.GroupBy(col.WithParent(alias).DisableAlias())
+}
+
+// Scan is a helper function that creates a StructMapper with NullTypeConverter, so that NULL values are skipped during scanning.
+// Example usage: bob.All(ctx, exec, psql.Select(query...), bob_helpers.Scan[BottomUpRow]())
+func Scan[T any](opts ...scan.MappingOption) scan.Mapper[T] {
+	allOpts := append([]scan.MappingOption{scan.WithTypeConverter(nullTypeConverter{})}, opts...)
+	return scan.StructMapper[T](allOpts...)
+}
+
+// nullTypeConverter is a custom TypeConverter that skips NULL values during scanning even if the destination type does not support NULLs.
+// This was stolen from https://github.com/stephenafamo/bob/blame/96da65fd88a50ae532079e8ea69746183f4af3a1/orm/load.go#L380
+type nullTypeConverter struct{}
+
+type wrapper struct {
+	IsNull bool
+	V      any
+}
+
+// Scan implements the sql.Scanner interface. If the wrapped type implements
+// sql.Scanner then it will call that.
+func (v *wrapper) Scan(value any) error {
+	if value == nil {
+		v.IsNull = true
+		return nil
+	}
+
+	if scanner, ok := v.V.(sql.Scanner); ok {
+		return scanner.Scan(value)
+	}
+
+	return opt.ConvertAssign(v.V, value)
+}
+
+func (nullTypeConverter) TypeToDestination(typ reflect.Type) reflect.Value {
+	val := reflect.ValueOf(&wrapper{
+		V: reflect.New(typ).Interface(),
+	})
+
+	return val
+}
+
+func (nullTypeConverter) ValueFromDestination(val reflect.Value) reflect.Value {
+	return val.Elem().FieldByName("V").Elem().Elem()
+}

v2/go.mod

@@ -1,27 +1,26 @@
 module github.com/top-solution/go-libs/v2
 
-go 1.24
+go 1.24.0
 
 require (
 	github.com/ardanlabs/conf/v3 v3.4.0
 	github.com/danielgtaylor/huma/v2 v2.34.1
 	github.com/goccy/go-yaml v1.15.19
 	github.com/golang-jwt/jwt/v4 v4.5.1
-	github.com/lib/pq v1.10.7
+	github.com/lib/pq v1.10.9
 	github.com/lmittmann/tint v1.0.7
 	github.com/ory/ladon v1.3.0
 	github.com/pressly/goose/v3 v3.24.1
 	github.com/serjlee/frequency v1.1.0
-	github.com/stephenafamo/bob v0.30.0
+	github.com/stephenafamo/bob v0.41.1
 	github.com/stretchr/testify v1.10.0
 	github.com/volatiletech/sqlboiler/v4 v4.18.0
 	golang.org/x/text v0.25.0
 	gopkg.in/gomail.v2 v2.0.0-20160411212932-81ebce5c23df
 )
 
 require (
-	github.com/aarondl/json v0.0.0-20221020222930-8b0db17ef1bf // indirect
-	github.com/aarondl/opt v0.0.0-20230114172057-b91f370c41f0 // indirect
+	github.com/aarondl/opt v0.0.0-20250607033636-982744e1bd65 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/dlclark/regexp2 v1.2.0 // indirect
 	github.com/friendsofgo/errors v0.9.2 // indirect
@@ -32,8 +31,8 @@ require (
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/qdm12/reprint v0.0.0-20200326205758-722754a53494 // indirect
 	github.com/sethvargo/go-retry v0.3.0 // indirect
-	github.com/spf13/cast v1.5.0 // indirect
-	github.com/stephenafamo/scan v0.6.1 // indirect
+	github.com/spf13/cast v1.7.0 // indirect
+	github.com/stephenafamo/scan v0.7.0 // indirect
 	github.com/volatiletech/inflect v0.0.1 // indirect
 	github.com/volatiletech/strmangle v0.0.6 // indirect
 	go.uber.org/multierr v1.11.0 // indirect