VictoriaMetrics/lib/promscrape/discovery/dockerswarm/api.go
Aliaksandr Valialkin 434f22f871
lib/promscrape: follow-up for 8537533beb
- Add a comment describing the purpose of the `role` field inside `apiConfig` struct
- Revert changes at lib/promscrape/discovery/dockerswarm/dockerswarm.go ,
  since they reduce code readability. E.g. the reader needs to look up the named string constants
  in order to get their values.
2023-01-11 22:56:48 -08:00

88 lines
2.3 KiB
Go

package dockerswarm
import (
"encoding/json"
"fmt"
"net/url"
"strings"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discoveryutils"
)
var configMap = discoveryutils.NewConfigMap()
type apiConfig struct {
client *discoveryutils.Client
port int
// role is the type of objects to discover.
//
// filtersQueryArg is applied only to the given role - the rest of objects are queried without filters.
role string
// filtersQueryArg contains escaped `filters` query arg to add to each request to Docker Swarm API.
filtersQueryArg string
}
func getAPIConfig(sdc *SDConfig, baseDir string) (*apiConfig, error) {
v, err := configMap.Get(sdc, func() (interface{}, error) { return newAPIConfig(sdc, baseDir) })
if err != nil {
return nil, err
}
return v.(*apiConfig), nil
}
func newAPIConfig(sdc *SDConfig, baseDir string) (*apiConfig, error) {
cfg := &apiConfig{
port: sdc.Port,
filtersQueryArg: getFiltersQueryArg(sdc.Filters),
}
if cfg.port == 0 {
cfg.port = 80
}
ac, err := sdc.HTTPClientConfig.NewConfig(baseDir)
if err != nil {
return nil, fmt.Errorf("cannot parse auth config: %w", err)
}
proxyAC, err := sdc.ProxyClientConfig.NewConfig(baseDir)
if err != nil {
return nil, fmt.Errorf("cannot parse proxy auth config: %w", err)
}
client, err := discoveryutils.NewClient(sdc.Host, ac, sdc.ProxyURL, proxyAC)
if err != nil {
return nil, fmt.Errorf("cannot create HTTP client for %q: %w", sdc.Host, err)
}
cfg.client = client
cfg.role = sdc.Role
return cfg, nil
}
func (cfg *apiConfig) getAPIResponse(path, filtersQueryArg string) ([]byte, error) {
if len(filtersQueryArg) > 0 {
separator := "?"
if strings.Contains(path, "?") {
separator = "&"
}
path += separator + "filters=" + cfg.filtersQueryArg
}
return cfg.client.GetAPIResponse(path)
}
// Encodes filters as `map[string][]string` and then marshals it to JSON.
// Reference: https://docs.docker.com/engine/api/v1.41/#tag/Task
func getFiltersQueryArg(filters []Filter) string {
if len(filters) == 0 {
return ""
}
m := make(map[string][]string)
for _, f := range filters {
m[f.Name] = f.Values
}
buf, err := json.Marshal(m)
if err != nil {
logger.Panicf("BUG: unexpected error in json.Marshal: %s", err)
}
return url.QueryEscape(string(buf))
}