Generator clean up refactoring.

generator/postgres-metadata/table_info.go

@@ -0,0 +1,116 @@
+package postgres_metadata
+
+import (
+	"database/sql"
+	"github.com/serenize/snaker"
+	"strings"
+)
+
+type TableInfo struct {
+	SchemaName  string
+	name        string
+	PrimaryKeys map[string]bool
+	Columns     []ColumnInfo
+}
+
+func (t TableInfo) Name() string {
+	return t.name
+}
+
+func (t TableInfo) IsUnique(columnName string) bool {
+	return t.PrimaryKeys[columnName]
+}
+
+func (t TableInfo) GetImports() []string {
+	imports := map[string]string{}
+
+	for _, column := range t.Columns {
+		columnType := column.GoBaseType()
+
+		switch columnType {
+		case "time.Time":
+			imports["time.Time"] = "time"
+		case "uuid.UUID":
+			imports["uuid.UUID"] = "github.com/google/uuid"
+		case "types.JSONText":
+			imports["types.JSONText"] = "github.com/sub0zero/go-sqlbuilder/types"
+		}
+	}
+
+	ret := []string{}
+
+	for _, packageImport := range imports {
+		ret = append(ret, packageImport)
+	}
+
+	return ret
+}
+
+func (t TableInfo) ToGoModelStructName() string {
+	return snaker.SnakeToCamel(t.name)
+}
+
+func (t TableInfo) ToGoVarName() string {
+	return snaker.SnakeToCamel(t.name)
+}
+
+func (t TableInfo) ToGoStructName() string {
+	return snaker.SnakeToCamel(t.name) + "Table"
+}
+
+func (t TableInfo) ToGoColumnFieldList(sep string) string {
+	columnNames := []string{}
+	for _, columnInfo := range t.Columns {
+		columnNames = append(columnNames, columnInfo.ToGoVarName())
+	}
+	return strings.Join(columnNames, sep)
+}
+
+func GetTableInfo(db *sql.DB, dbName, schemaName, tableName string) (tableInfo TableInfo, err error) {
+
+	tableInfo.SchemaName = schemaName
+	tableInfo.name = tableName
+
+	tableInfo.PrimaryKeys, err = getPrimaryKeys(db, dbName, schemaName, tableName)
+	if err != nil {
+		return
+	}
+
+	tableInfo.Columns, err = getColumnInfos(db, dbName, schemaName, tableName)
+
+	if err != nil {
+		return
+	}
+
+	return
+}
+
+func getPrimaryKeys(db *sql.DB, dbName, schemaName, tableName string) (map[string]bool, error) {
+	query := `
+SELECT c.column_name
+FROM information_schema.key_column_usage AS c
+LEFT JOIN information_schema.table_constraints AS t
+ON t.constraint_name = c.constraint_name
+WHERE t.table_catalog = $1 AND t.table_schema = $2 AND t.table_name = $3 AND t.constraint_type = 'PRIMARY KEY';
+`
+	rows, err := db.Query(query, dbName, schemaName, tableName)
+
+	if err != nil {
+		return nil, err
+	}
+
+	primaryKeyMap := map[string]bool{}
+
+	for rows.Next() {
+		primaryKey := ""
+		err := rows.Scan(&primaryKey)
+
+		if err != nil {
+			return nil, err
+		}
+
+		primaryKeyMap[primaryKey] = true
+	}
+
+	return primaryKeyMap, nil
+}