Files
grafana/pkg/tsdb/prometheus/prometheus.go
T
Travis Patterson c45313a268 Propagate all headers (#43812) (#43922)
* Propagate all headers

* stable header order

(cherry picked from commit 9eb82f9fff)
2022-01-11 14:39:52 -07:00

126 lines
3.2 KiB
Go

package prometheus
import (
"context"
"encoding/json"
"errors"
"fmt"
"regexp"
"github.com/grafana/grafana/pkg/tsdb/prometheus/promclient"
"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/plugins"
"github.com/grafana/grafana/pkg/plugins/backendplugin/coreplugin"
"github.com/grafana/grafana/pkg/tsdb/intervalv2"
apiv1 "github.com/prometheus/client_golang/api/prometheus/v1"
)
var (
plog = log.New("tsdb.prometheus")
legendFormat = regexp.MustCompile(`\{\{\s*(.+?)\s*\}\}`)
safeRes = 11000
)
type Service struct {
intervalCalculator intervalv2.Calculator
im instancemgmt.InstanceManager
}
func ProvideService(httpClientProvider httpclient.Provider, registrar plugins.CoreBackendRegistrar) (*Service, error) {
plog.Debug("initializing")
im := datasource.NewInstanceManager(newInstanceSettings(httpClientProvider))
s := &Service{
intervalCalculator: intervalv2.NewCalculator(),
im: im,
}
factory := coreplugin.New(backend.ServeOpts{
QueryDataHandler: s,
})
if err := registrar.LoadAndRegister("prometheus", factory); err != nil {
plog.Error("Failed to register plugin", "error", err)
return nil, err
}
return s, nil
}
func newInstanceSettings(httpClientProvider httpclient.Provider) datasource.InstanceFactoryFunc {
return func(settings backend.DataSourceInstanceSettings) (instancemgmt.Instance, error) {
var jsonData promclient.JsonData
err := json.Unmarshal(settings.JSONData, &jsonData)
if err != nil {
return nil, fmt.Errorf("error reading settings: %w", err)
}
p := promclient.NewProvider(settings, jsonData, httpClientProvider, plog)
pc, err := promclient.NewProviderCache(p)
if err != nil {
return nil, err
}
mdl := DatasourceInfo{
ID: settings.ID,
URL: settings.URL,
TimeInterval: jsonData.TimeInterval,
getClient: pc.GetClient,
}
return mdl, 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")
}
q := req.Queries[0]
dsInfo, err := s.getDSInfo(req.PluginContext)
if err != nil {
return nil, err
}
var result *backend.QueryDataResponse
switch q.QueryType {
case "timeSeriesQuery":
fallthrough
default:
result, err = s.executeTimeSeriesQuery(ctx, req, dsInfo)
}
return result, err
}
func (s *Service) getDSInfo(pluginCtx backend.PluginContext) (*DatasourceInfo, error) {
i, err := s.im.Get(pluginCtx)
if err != nil {
return nil, err
}
instance := i.(DatasourceInfo)
return &instance, 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
}