grafana/pkg/tsdb/prometheus/prometheus.go

107 lines
3.0 KiB
Go

package prometheus
import (
"context"
"encoding/json"
"errors"
"fmt"
"github.com/grafana/grafana-plugin-sdk-go/backend"
"github.com/grafana/grafana-plugin-sdk-go/backend/datasource"
"github.com/grafana/grafana-plugin-sdk-go/backend/instancemgmt"
"github.com/grafana/grafana/pkg/infra/httpclient"
"github.com/grafana/grafana/pkg/infra/log"
"github.com/grafana/grafana/pkg/infra/tracing"
"github.com/grafana/grafana/pkg/services/featuremgmt"
"github.com/grafana/grafana/pkg/setting"
"github.com/grafana/grafana/pkg/tsdb/prometheus/buffered"
"github.com/grafana/grafana/pkg/tsdb/prometheus/querydata"
apiv1 "github.com/prometheus/client_golang/api/prometheus/v1"
)
var plog = log.New("tsdb.prometheus")
type Service struct {
im instancemgmt.InstanceManager
features featuremgmt.FeatureToggles
}
type instance struct {
buffered *buffered.Buffered
queryData *querydata.QueryData
}
func ProvideService(httpClientProvider httpclient.Provider, cfg *setting.Cfg, features featuremgmt.FeatureToggles, tracer tracing.Tracer) *Service {
plog.Debug("initializing")
return &Service{
im: datasource.NewInstanceManager(newInstanceSettings(httpClientProvider, cfg, features, tracer)),
features: features,
}
}
func newInstanceSettings(httpClientProvider httpclient.Provider, cfg *setting.Cfg, features featuremgmt.FeatureToggles, tracer tracing.Tracer) datasource.InstanceFactoryFunc {
return func(settings backend.DataSourceInstanceSettings) (instancemgmt.Instance, error) {
var jsonData map[string]interface{}
err := json.Unmarshal(settings.JSONData, &jsonData)
if err != nil {
return nil, fmt.Errorf("error reading settings: %w", err)
}
b, err := buffered.New(httpClientProvider, cfg, features, tracer, settings, plog)
if err != nil {
return nil, err
}
qd, err := querydata.New(httpClientProvider, cfg, features, tracer, settings, plog)
if err != nil {
return nil, err
}
return instance{
buffered: b,
queryData: qd,
}, nil
}
}
func (s *Service) QueryData(ctx context.Context, req *backend.QueryDataRequest) (*backend.QueryDataResponse, error) {
if len(req.Queries) == 0 {
return &backend.QueryDataResponse{}, fmt.Errorf("query contains no queries")
}
i, err := s.getInstance(req.PluginContext)
if err != nil {
return nil, err
}
if s.features.IsEnabled(featuremgmt.FlagPrometheusStreamingJSONParser) || s.features.IsEnabled(featuremgmt.FlagPrometheusWideSeries) {
return i.queryData.Execute(ctx, req)
}
return i.buffered.ExecuteTimeSeriesQuery(ctx, req)
}
func (s *Service) getInstance(pluginCtx backend.PluginContext) (*instance, error) {
i, err := s.im.Get(pluginCtx)
if err != nil {
return nil, err
}
in := i.(instance)
return &in, nil
}
// IsAPIError returns whether err is or wraps a Prometheus error.
func IsAPIError(err error) bool {
// Check if the right error type is in err's chain.
var e *apiv1.Error
return errors.As(err, &e)
}
func ConvertAPIError(err error) error {
var e *apiv1.Error
if errors.As(err, &e) {
return fmt.Errorf("%s: %s", e.Msg, e.Detail)
}
return err
}