✨ feat: added func to get table info #5

Author: pnguyen215

go.mod

@@ -18,4 +18,5 @@ require (
 	github.com/natefinch/lumberjack v2.0.0+incompatible // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
 	golang.org/x/sys v0.12.0 // indirect
+	gopkg.in/guregu/null.v3 v3.5.0
 )

go.sum

@@ -42,6 +42,8 @@ golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.12.0 h1:CM0HF96J0hcLAwsHPJZjfdNzs0gftsLfgKt57wWHJ0o=
 golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/guregu/null.v3 v3.5.0 h1:xTcasT8ETfMcUHn0zTvIYtQud/9Mx5dJqD554SZct0o=
+gopkg.in/guregu/null.v3 v3.5.0/go.mod h1:E4tX2Qe3h7QdL+uZ3a0vqvYwKQsRSQKM5V4YltdgH9Y=
 gopkg.in/natefinch/lumberjack.v2 v2.2.1 h1:bBRl1b0OH9s/DuPhuXpNl+VtCaJXFZ5/uEFST95x9zc=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=

postgresconn/postgresconn_model.go

@@ -1,5 +1,7 @@
 package postgresconn
 
+import "gopkg.in/guregu/null.v3"
+
 type IFunctionDescriptor struct {
 	RoutineName   string `db:"routine_name" json:"routine_name,omitempty"`
 	DataType      string `db:"data_type" json:"type,omitempty"`
@@ -12,3 +14,9 @@ type ITableDescriptor struct {
 	Type       string `json:"type,omitempty" db:"type"`
 	Descriptor string `json:"descriptor,omitempty" db:"descriptor"`
 }
+
+type ITableInfo struct {
+	Column    string   `json:"column" db:"column_name"`
+	Type      string   `json:"type" db:"data_type"`
+	MaxLength null.Int `json:"max_length" db:"character_maximum_length"`
+}

postgresconn/postgresconn_service.go

@@ -27,6 +27,7 @@ type PostgresService interface {
 	ExecuteBatch(statements []string) error
 	ExecuteBatchWithTransaction(statements []string) error
 	TableDescriptor(table string) ([]ITableDescriptor, error)
+	TableInfo(table string) ([]ITableInfo, error)
 }
 
 type postgresServiceImpl struct {
@@ -275,3 +276,33 @@ func (p *postgresServiceImpl) TableDescriptor(table string) ([]ITableDescriptor,
 	}
 	return results, nil
 }
+
+func (p *postgresServiceImpl) TableInfo(table string) ([]ITableInfo, error) {
+	s := `
+	SELECT
+		column_name,
+		data_type,
+		character_maximum_length
+	FROM
+		information_schema.columns
+	WHERE
+		table_name = $1;
+	`
+	rows, err := p.dbConn.Query(s, table)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var results []ITableInfo
+	for rows.Next() {
+		var m ITableInfo
+		if err := rows.Scan(&m.Column, &m.Type, &m.MaxLength); err != nil {
+			return nil, err
+		}
+		results = append(results, m)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	return results, nil
+}