Respect character_maximum_length when generating random values for st…

…ring columns

gen/bobgen-mysql/driver/mysql.go

@@ -9,6 +9,7 @@ import (
 	"strings"
 	"sync"
 
+	"github.com/aarondl/opt/null"
 	"github.com/go-sql-driver/mysql"
 	helpers "github.com/stephenafamo/bob/gen/bobgen-helpers"
 	"github.com/stephenafamo/bob/gen/drivers"
@@ -157,6 +158,7 @@ func (d *driver) TableDetails(ctx context.Context, info drivers.TableInfo, colFi
 	c.data_type,
 	c.column_default,
 	c.extra = 'auto_increment' AS autoincr,
+	c.character_maximum_length,
 	c.is_nullable = 'YES' AS nullable,
 	(c.extra = 'STORED GENERATED' OR c.extra = 'VIRTUAL GENERATED') is_generated
 	from information_schema.columns as c
@@ -188,7 +190,8 @@ func (d *driver) TableDetails(ctx context.Context, info drivers.TableInfo, colFi
 		var colName, colFullType, colComment, colType string
 		var autoIncr, nullable, generated bool
 		var defaultValue *string
-		if err := rows.Scan(&colName, &colFullType, &colComment, &colType, &defaultValue, &autoIncr, &nullable, &generated); err != nil {
+		var charMaxLen null.Val[int]
+		if err := rows.Scan(&colName, &colFullType, &colComment, &colType, &defaultValue, &autoIncr, &charMaxLen, &nullable, &generated); err != nil {
 			return "", "", nil, fmt.Errorf("unable to scan for table %s: %w", tableName, err)
 		}
 
@@ -197,12 +200,13 @@ func (d *driver) TableDetails(ctx context.Context, info drivers.TableInfo, colFi
 		}
 
 		column := drivers.Column{
-			Name:      colName,
-			Comment:   colComment,
-			DBType:    colType,
-			Nullable:  nullable,
-			Generated: generated,
-			AutoIncr:  autoIncr,
+			Name:       colName,
+			Comment:    colComment,
+			DBType:     colType,
+			Nullable:   nullable,
+			Generated:  generated,
+			AutoIncr:   autoIncr,
+			CharMaxLen: charMaxLen,
 		}
 
 		if defaultValue != nil {

gen/bobgen-psql/driver/psql.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"database/sql"
 	"fmt"
+	"github.com/aarondl/opt/null"
 	"sort"
 
 	"github.com/lib/pq"
@@ -230,6 +231,7 @@ func (d *driver) TableDetails(ctx context.Context, info drivers.TableInfo, colFi
 		) AS array_type,
 	c.domain_name,
 	c.column_default,
+	c.character_maximum_length,
 	coalesce(col_description(('"' || c.table_schema || '"."' || c.table_name || '"')::regclass::oid, ordinal_position), '') AS column_comment,
 	c.is_nullable = 'YES' AS is_nullable,
 	(
@@ -288,7 +290,8 @@ func (d *driver) TableDetails(ctx context.Context, info drivers.TableInfo, colFi
 		column_comment,
 		is_nullable,
 		is_generated,
-		is_identity
+		is_identity,
+		character_maximum_length
 	FROM (
 		%s
 	) AS c`, tableQuery) // matviewQuery, tableQuery)
@@ -325,16 +328,18 @@ func (d *driver) TableDetails(ctx context.Context, info drivers.TableInfo, colFi
 		var colName, colType, udtSchema, udtName, comment string
 		var defaultValue, arrayType, domainName *string
 		var nullable, generated, identity bool
-		if err := rows.Scan(&colName, &colType, &udtSchema, &udtName, &arrayType, &domainName, &defaultValue, &comment, &nullable, &generated, &identity); err != nil {
+		var charMaxLen null.Val[int]
+		if err := rows.Scan(&colName, &colType, &udtSchema, &udtName, &arrayType, &domainName, &defaultValue, &comment, &nullable, &generated, &identity, &charMaxLen); err != nil {
 			return "", "", nil, fmt.Errorf("unable to scan for table %s: %w", info.Key, err)
 		}
 
 		column := drivers.Column{
-			Name:      colName,
-			DBType:    colType,
-			Comment:   comment,
-			Nullable:  nullable,
-			Generated: generated,
+			Name:       colName,
+			DBType:     colType,
+			Comment:    comment,
+			Nullable:   nullable,
+			Generated:  generated,
+			CharMaxLen: charMaxLen,
 		}
 		info := colInfo{
 			UDTSchema: udtSchema,

gen/drivers/column.go

@@ -3,6 +3,7 @@ package drivers
 import (
 	"strings"
 
+	"github.com/aarondl/opt/null"
 	"github.com/volatiletech/strmangle"
 )
 
@@ -21,6 +22,8 @@ type Column struct {
 	// https://www.postgresql.org/docs/16/extend-type-system.html
 	DomainName string `json:"domain_name" yaml:"domain_name" toml:"domain_name"`
 
+	CharMaxLen null.Val[int] `json:"char_max_len" yaml:"char_max_len" toml:"char_max_len"`
+
 	Type string `json:"type" yaml:"type" toml:"type"`
 }
 

gen/templates/factory/03_create.go.tpl

@@ -8,14 +8,20 @@
 
 func ensureCreatable{{$tAlias.UpSingular}}(m *models.{{$tAlias.UpSingular}}Setter) {
 	{{range $column := $table.Columns -}}
-  {{- if $column.Default}}{{continue}}{{end -}}
-  {{- if $column.Nullable}}{{continue}}{{end -}}
+	{{- if $column.Default}}{{continue}}{{end -}}
+	{{- if $column.Nullable}}{{continue}}{{end -}}
 	{{- if $column.Generated}}{{continue}}{{end -}}
 	{{- $colAlias := $tAlias.Column $column.Name -}}
-  {{- $typDef :=  index $.Types $column.Type -}}
-  {{- $colTyp := or $typDef.AliasOf $column.Type -}}
-		if m.{{$colAlias}}.IsUnset() {
-        m.{{$colAlias}} = omit.From(random_{{normalizeType $column.Type}}(nil))
+	{{- $typDef :=  index $.Types $column.Type -}}
+	{{- $colTyp := or $typDef.AliasOf $column.Type -}}
+	{{- $wrapStart := "" -}}
+	{{- $wrapEnd := "" -}}
+	{{- if $column.CharMaxLen.IsSet -}}
+		{{- $wrapStart = "truncateString(" -}}
+		{{- $wrapEnd = printf `,%d )` $column.CharMaxLen.GetOrZero -}}
+	{{- end -}}
+	if m.{{$colAlias}}.IsUnset() {
+		m.{{$colAlias}} = omit.From({{$wrapStart}}random_{{normalizeType $column.Type}}(nil){{$wrapEnd}})
     }
 	{{end -}}
 }

gen/templates/factory/11_column_mods.go.tpl

@@ -24,6 +24,13 @@ func (m {{$tAlias.DownSingular}}Mods) RandomizeAllColumns(f *faker.Faker) {{$tAl
 	{{- $colTyp = printf "null.Val[%s]" $colTyp -}}
 {{- end -}}
 
+{{- $wrapStart := "" -}}
+{{- $wrapEnd := "" -}}
+{{- if $column.CharMaxLen.IsSet -}}
+	{{- $wrapStart = "truncateString(" -}}
+	{{- $wrapEnd = printf `,%d )` $column.CharMaxLen.GetOrZero -}}
+{{- end -}}
+
 // Set the model columns to this value
 func (m {{$tAlias.DownSingular}}Mods) {{$colAlias}}(val {{$colTyp}}) {{$tAlias.UpSingular}}Mod {
 	return {{$tAlias.UpSingular}}ModFunc(func(o *{{$tAlias.UpSingular}}Template) {
@@ -59,9 +66,9 @@ func (m {{$tAlias.DownSingular}}Mods) Random{{$colAlias}}(f *faker.Faker) {{$tAl
           return null.FromPtr[{{or $typDef.AliasOf $column.Type}}](nil)
         }
 
-        return null.From(random_{{normalizeType $column.Type}}(f))
+        return null.From({{$wrapStart}}random_{{normalizeType $column.Type}}(f){{$wrapEnd}})
 			{{- else -}}
-				return random_{{normalizeType $column.Type}}(f)
+				return {{$wrapStart}}random_{{normalizeType $column.Type}}(f){{$wrapEnd}}
 			{{- end}}
 		}
 	})

gen/templates/factory/singleton/bobfactory_random.go.tpl

@@ -3,10 +3,12 @@
 
 var defaultFaker = faker.New()
 
+{{$hasCharMaxLen := false}}
 {{$doneTypes := dict }}
 {{- range $table := .Tables}}
 {{- $tAlias := $.Aliases.Table $table.Key}}
   {{range $column := $table.Columns -}}
+      {{- if $column.CharMaxLen -}}{{- $hasCharMaxLen = true -}}{{- end -}}
       {{- $colTyp := $column.Type -}}
       {{- if hasKey $doneTypes $column.Type}}{{continue}}{{end -}}
       {{- $_ :=  set $doneTypes $column.Type nil -}}
@@ -34,3 +36,12 @@ var defaultFaker = faker.New()
       {{$typDef.RandomExpr}}
     }
 {{end -}}
+
+{{- if $hasCharMaxLen -}}
+func truncateString(s string, maxLen int) string {
+	if len(s) > maxLen {
+		return s[:maxLen]
+	}
+	return s
+}
+{{- end -}}