grafana/pkg/tsdb/sql_engine.go
2018-05-29 08:44:03 +02:00

297 lines
7.7 KiB
Go

package tsdb
import (
"context"
"fmt"
"sync"
"time"
"github.com/grafana/grafana/pkg/components/null"
"github.com/go-xorm/core"
"github.com/go-xorm/xorm"
"github.com/grafana/grafana/pkg/components/simplejson"
"github.com/grafana/grafana/pkg/models"
)
// SqlEngine is a wrapper class around xorm for relational database data sources.
type SqlEngine interface {
InitEngine(driverName string, dsInfo *models.DataSource, cnnstr string) error
Query(
ctx context.Context,
ds *models.DataSource,
query *TsdbQuery,
transformToTimeSeries func(query *Query, rows *core.Rows, result *QueryResult, tsdbQuery *TsdbQuery) error,
transformToTable func(query *Query, rows *core.Rows, result *QueryResult, tsdbQuery *TsdbQuery) error,
) (*Response, error)
}
// SqlMacroEngine interpolates macros into sql. It takes in the Query to have access to query context and
// timeRange to be able to generate queries that use from and to.
type SqlMacroEngine interface {
Interpolate(query *Query, timeRange *TimeRange, sql string) (string, error)
}
type DefaultSqlEngine struct {
MacroEngine SqlMacroEngine
XormEngine *xorm.Engine
}
type engineCacheType struct {
cache map[int64]*xorm.Engine
versions map[int64]int
sync.Mutex
}
var engineCache = engineCacheType{
cache: make(map[int64]*xorm.Engine),
versions: make(map[int64]int),
}
// InitEngine creates the db connection and inits the xorm engine or loads it from the engine cache
func (e *DefaultSqlEngine) InitEngine(driverName string, dsInfo *models.DataSource, cnnstr string) error {
engineCache.Lock()
defer engineCache.Unlock()
if engine, present := engineCache.cache[dsInfo.Id]; present {
if version := engineCache.versions[dsInfo.Id]; version == dsInfo.Version {
e.XormEngine = engine
return nil
}
}
engine, err := xorm.NewEngine(driverName, cnnstr)
if err != nil {
return err
}
engine.SetMaxOpenConns(10)
engine.SetMaxIdleConns(10)
engineCache.cache[dsInfo.Id] = engine
e.XormEngine = engine
return nil
}
// Query is a default implementation of the Query method for an SQL data source.
// The caller of this function must implement transformToTimeSeries and transformToTable and
// pass them in as parameters.
func (e *DefaultSqlEngine) Query(
ctx context.Context,
dsInfo *models.DataSource,
tsdbQuery *TsdbQuery,
transformToTimeSeries func(query *Query, rows *core.Rows, result *QueryResult, tsdbQuery *TsdbQuery) error,
transformToTable func(query *Query, rows *core.Rows, result *QueryResult, tsdbQuery *TsdbQuery) error,
) (*Response, error) {
result := &Response{
Results: make(map[string]*QueryResult),
}
session := e.XormEngine.NewSession()
defer session.Close()
db := session.DB()
for _, query := range tsdbQuery.Queries {
rawSql := query.Model.Get("rawSql").MustString()
if rawSql == "" {
continue
}
queryResult := &QueryResult{Meta: simplejson.New(), RefId: query.RefId}
result.Results[query.RefId] = queryResult
rawSql, err := e.MacroEngine.Interpolate(query, tsdbQuery.TimeRange, rawSql)
if err != nil {
queryResult.Error = err
continue
}
queryResult.Meta.Set("sql", rawSql)
rows, err := db.Query(rawSql)
if err != nil {
queryResult.Error = err
continue
}
defer rows.Close()
format := query.Model.Get("format").MustString("time_series")
switch format {
case "time_series":
err := transformToTimeSeries(query, rows, queryResult, tsdbQuery)
if err != nil {
queryResult.Error = err
continue
}
case "table":
err := transformToTable(query, rows, queryResult, tsdbQuery)
if err != nil {
queryResult.Error = err
continue
}
}
}
return result, nil
}
// ConvertSqlTimeColumnToEpochMs converts column named time to unix timestamp in milliseconds
// to make native datetime types and epoch dates work in annotation and table queries.
func ConvertSqlTimeColumnToEpochMs(values RowValues, timeIndex int) {
if timeIndex >= 0 {
switch value := values[timeIndex].(type) {
case time.Time:
values[timeIndex] = float64(value.UnixNano()) / float64(time.Millisecond)
case *time.Time:
if value != nil {
values[timeIndex] = float64((*value).UnixNano()) / float64(time.Millisecond)
}
case int64:
values[timeIndex] = int64(EpochPrecisionToMs(float64(value)))
case *int64:
if value != nil {
values[timeIndex] = int64(EpochPrecisionToMs(float64(*value)))
}
case uint64:
values[timeIndex] = int64(EpochPrecisionToMs(float64(value)))
case *uint64:
if value != nil {
values[timeIndex] = int64(EpochPrecisionToMs(float64(*value)))
}
case int32:
values[timeIndex] = int64(EpochPrecisionToMs(float64(value)))
case *int32:
if value != nil {
values[timeIndex] = int64(EpochPrecisionToMs(float64(*value)))
}
case uint32:
values[timeIndex] = int64(EpochPrecisionToMs(float64(value)))
case *uint32:
if value != nil {
values[timeIndex] = int64(EpochPrecisionToMs(float64(*value)))
}
case float64:
values[timeIndex] = EpochPrecisionToMs(value)
case *float64:
if value != nil {
values[timeIndex] = EpochPrecisionToMs(*value)
}
case float32:
values[timeIndex] = EpochPrecisionToMs(float64(value))
case *float32:
if value != nil {
values[timeIndex] = EpochPrecisionToMs(float64(*value))
}
}
}
}
// ConvertSqlValueColumnToFloat converts timeseries value column to float.
func ConvertSqlValueColumnToFloat(columnName string, columnValue interface{}) (null.Float, error) {
var value null.Float
switch typedValue := columnValue.(type) {
case int:
value = null.FloatFrom(float64(typedValue))
case *int:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case int64:
value = null.FloatFrom(float64(typedValue))
case *int64:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case int32:
value = null.FloatFrom(float64(typedValue))
case *int32:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case int16:
value = null.FloatFrom(float64(typedValue))
case *int16:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case int8:
value = null.FloatFrom(float64(typedValue))
case *int8:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case uint:
value = null.FloatFrom(float64(typedValue))
case *uint:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case uint64:
value = null.FloatFrom(float64(typedValue))
case *uint64:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case uint32:
value = null.FloatFrom(float64(typedValue))
case *uint32:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case uint16:
value = null.FloatFrom(float64(typedValue))
case *uint16:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case uint8:
value = null.FloatFrom(float64(typedValue))
case *uint8:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case float64:
value = null.FloatFrom(typedValue)
case *float64:
value = null.FloatFromPtr(typedValue)
case float32:
value = null.FloatFrom(float64(typedValue))
case *float32:
if typedValue == nil {
value.Valid = false
} else {
value = null.FloatFrom(float64(*typedValue))
}
case nil:
value.Valid = false
default:
return null.NewFloat(0, false), fmt.Errorf("Value column must have numeric datatype, column: %s type: %T value: %v", columnName, typedValue, typedValue)
}
return value, nil
}