connector.go•8.5 kB
package mssql
import (
"context"
"fmt"
"strconv"
"strings"
"github.com/centralmind/gateway/castx"
"github.com/centralmind/gateway/connectors"
"github.com/centralmind/gateway/model"
"github.com/jmoiron/sqlx"
_ "github.com/microsoft/go-mssqldb"
"golang.org/x/xerrors"
)
func init() {
connectors.Register[Config](func(cfg Config) (connectors.Connector, error) {
connStr := cfg.ConnectionString()
db, err := sqlx.Connect("sqlserver", connStr)
if err != nil {
return nil, fmt.Errorf("unable to connect to mssql: %v", err)
}
return &Connector{
config: cfg,
db: db,
base: &connectors.BaseConnector{DB: db},
}, nil
})
}
// Connector implements the connectors.Connector interface for Microsoft SQL Server
type Connector struct {
config Config
db *sqlx.DB
base *connectors.BaseConnector
}
func (c Connector) Config() connectors.Config {
return c.config
}
// GuessColumnType implements TypeGuesser interface for MSSQL
func (c *Connector) GuessColumnType(sqlType string) model.ColumnType {
upperType := strings.ToUpper(sqlType)
// String types
switch upperType {
case "VARCHAR", "CHAR", "TEXT", "NVARCHAR", "NCHAR", "NTEXT",
"XML", "UNIQUEIDENTIFIER":
return model.TypeString
}
// Numeric types
switch upperType {
case "DECIMAL", "NUMERIC", "FLOAT", "REAL", "MONEY", "SMALLMONEY":
return model.TypeNumber
}
// Integer types
switch upperType {
case "INT", "BIGINT", "SMALLINT", "TINYINT":
return model.TypeInteger
}
// Boolean type
switch upperType {
case "BIT":
return model.TypeBoolean
}
// Date/Time types
switch upperType {
case "DATE", "TIME", "DATETIME", "DATETIME2", "DATETIMEOFFSET", "SMALLDATETIME":
return model.TypeDatetime
}
// Binary types
switch upperType {
case "BINARY", "VARBINARY", "IMAGE":
return model.TypeString
}
// Default to string for unknown types
return model.TypeString
}
func (c Connector) Sample(ctx context.Context, table model.Table) ([]map[string]any, error) {
// Use the schema from config, default to 'dbo' if not specified
schema := "dbo"
if c.config.Schema != "" {
schema = c.config.Schema
}
// Create schema-qualified table name
qualifiedTableName := fmt.Sprintf("[%s].[%s]", schema, table.Name)
rows, err := c.db.NamedQuery(fmt.Sprintf("SELECT TOP 5 * FROM %s", qualifiedTableName), map[string]any{})
if err != nil {
return nil, xerrors.Errorf("unable to query db: %w", err)
}
defer rows.Close()
res := make([]map[string]any, 0, 5)
for rows.Next() {
row := map[string]any{}
if err := rows.MapScan(row); err != nil {
return nil, xerrors.Errorf("unable to scan row: %w", err)
}
res = append(res, row)
}
return res, nil
}
func (c Connector) Discovery(ctx context.Context, tablesList []string) ([]model.Table, error) {
// Use the schema from config, default to 'dbo' if not specified
schema := "dbo"
if c.config.Schema != "" {
schema = c.config.Schema
}
// Create a map for quick lookups if tablesList is provided
tableSet := make(map[string]bool)
if len(tablesList) > 0 {
for _, table := range tablesList {
tableSet[table] = true
}
}
// Build query with or without table filter
var query string
var args []interface{}
args = append(args, schema) // First parameter is always schema
if len(tablesList) > 0 {
// Build dynamic IN clause with proper parameterization
placeholders := make([]string, len(tablesList))
for i, table := range tablesList {
placeholders[i] = fmt.Sprintf("@p%d", i+2) // Start from @p2 since @p1 is schema
args = append(args, table)
}
query = fmt.Sprintf(`
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = @p1
AND TABLE_TYPE = 'BASE TABLE'
AND TABLE_NAME IN (%s)`, strings.Join(placeholders, ","))
} else {
query = `
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = @p1
AND TABLE_TYPE = 'BASE TABLE'`
}
rows, err := c.db.QueryContext(ctx, query, args...)
if err != nil {
return nil, xerrors.Errorf("unable to query tables: %w", err)
}
defer rows.Close()
var tables []model.Table
for rows.Next() {
var tableName string
if err := rows.Scan(&tableName); err != nil {
return nil, xerrors.Errorf("unable to scan table name: %w", err)
}
columns, err := c.LoadsColumns(ctx, tableName)
if err != nil {
return nil, xerrors.Errorf("unable to load columns for table %s: %w", tableName, err)
}
// Get the total row count for this table
var rowCount int
qualifiedTableName := fmt.Sprintf("[%s].[%s]", schema, tableName)
countQuery := fmt.Sprintf("SELECT COUNT(*) FROM %s", qualifiedTableName)
err = c.db.Get(&rowCount, countQuery)
if err != nil {
return nil, xerrors.Errorf("unable to get row count for table %s: %w", tableName, err)
}
table := model.Table{
Name: qualifiedTableName,
Columns: columns,
RowCount: rowCount,
}
tables = append(tables, table)
}
return tables, nil
}
func (c Connector) Ping(ctx context.Context) error {
rows, err := c.db.QueryContext(ctx, "SELECT 1")
if err != nil {
return xerrors.Errorf("unable to ping db: %w", err)
}
defer rows.Close()
for rows.Next() {
var res int
if err := rows.Scan(&res); err != nil {
return xerrors.Errorf("unable to scan ping result: %w", err)
}
}
if rows.Err() != nil {
return xerrors.Errorf("rows fetcher failed: %w", err)
}
return nil
}
func (c Connector) Query(ctx context.Context, endpoint model.Endpoint, params map[string]any) ([]map[string]any, error) {
processed, err := castx.ParamsE(endpoint, params)
if err != nil {
return nil, xerrors.Errorf("unable to process params: %w", err)
}
// Convert parameters to their proper types based on endpoint parameter definitions
for _, param := range endpoint.Params {
if value, ok := processed[param.Name]; ok {
switch param.Type {
case "integer":
if strVal, ok := value.(string); ok {
if intVal, err := strconv.Atoi(strVal); err == nil {
processed[param.Name] = intVal
}
}
case "number":
if strVal, ok := value.(string); ok {
if floatVal, err := strconv.ParseFloat(strVal, 64); err == nil {
processed[param.Name] = floatVal
}
}
case "boolean":
if strVal, ok := value.(string); ok {
if boolVal, err := strconv.ParseBool(strVal); err == nil {
processed[param.Name] = boolVal
}
}
case "date-time":
// Keep as string for date-time as SQL Server can handle ISO8601 strings
continue
case "string":
// No conversion needed for strings
continue
}
}
}
rows, err := c.db.NamedQuery(endpoint.Query, processed)
if err != nil {
return nil, xerrors.Errorf("unable to query db: %w", err)
}
defer rows.Close()
res := make([]map[string]any, 0)
for rows.Next() {
row := map[string]any{}
if err := rows.MapScan(row); err != nil {
return nil, xerrors.Errorf("unable to scan row: %w", err)
}
res = append(res, row)
}
return res, nil
}
func (c Connector) LoadsColumns(ctx context.Context, tableName string) ([]model.ColumnSchema, error) {
schema := "dbo"
if c.config.Schema != "" {
schema = c.config.Schema
}
rows, err := c.db.QueryContext(
ctx,
`SELECT
c.COLUMN_NAME,
c.DATA_TYPE,
c.IS_NULLABLE,
CASE WHEN pk.COLUMN_NAME IS NOT NULL THEN 1 ELSE 0 END as IS_PRIMARY_KEY
FROM INFORMATION_SCHEMA.COLUMNS c
LEFT JOIN (
SELECT ku.COLUMN_NAME
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc
JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE ku
ON tc.CONSTRAINT_NAME = ku.CONSTRAINT_NAME
WHERE tc.CONSTRAINT_TYPE = 'PRIMARY KEY'
AND ku.TABLE_NAME = @p1
AND ku.TABLE_SCHEMA = @p2
) pk ON c.COLUMN_NAME = pk.COLUMN_NAME
WHERE c.TABLE_NAME = @p1
AND c.TABLE_SCHEMA = @p2`,
tableName, schema,
)
if err != nil {
return nil, xerrors.Errorf("unable to query columns: %w", err)
}
defer rows.Close()
var columns []model.ColumnSchema
for rows.Next() {
var name, dataType, isNullable string
var isPrimaryKey bool
if err := rows.Scan(&name, &dataType, &isNullable, &isPrimaryKey); err != nil {
return nil, xerrors.Errorf("unable to scan column info: %w", err)
}
columns = append(columns, model.ColumnSchema{
Name: name,
Type: c.GuessColumnType(dataType),
PrimaryKey: isPrimaryKey,
})
}
return columns, nil
}
// InferQuery implements the Connector interface
func (c *Connector) InferQuery(ctx context.Context, query string) ([]model.ColumnSchema, error) {
return c.base.InferResultColumns(ctx, query, c)
}