retrieval: fix IPv6 port default, add tests

This fixes port defaulting for IPv6 addresses and restructures
and test the construction of target label sets.
This commit is contained in:
Fabian Reinartz 2016-09-05 14:17:10 +02:00
parent 75bae065fd
commit 17cdd4f966
2 changed files with 223 additions and 64 deletions

View file

@ -15,6 +15,7 @@ package retrieval
import (
"fmt"
"net"
"sort"
"strings"
"sync"
@ -417,79 +418,103 @@ func providersFromConfig(cfg *config.ScrapeConfig) map[string]TargetProvider {
return providers
}
// populateLabels builds a label set from the given label set and scrape configuration.
// It returns a label set before relabeling was applied as the second return value.
// Returns a nil label set if the target is dropped during relabeling.
func populateLabels(lset model.LabelSet, cfg *config.ScrapeConfig) (res, orig model.LabelSet, err error) {
if _, ok := lset[model.AddressLabel]; !ok {
return nil, nil, fmt.Errorf("no address")
}
// Copy labels into the labelset for the target if they are not
// set already. Apply the labelsets in order of decreasing precedence.
scrapeLabels := model.LabelSet{
model.SchemeLabel: model.LabelValue(cfg.Scheme),
model.MetricsPathLabel: model.LabelValue(cfg.MetricsPath),
model.JobLabel: model.LabelValue(cfg.JobName),
}
for ln, lv := range scrapeLabels {
if _, ok := lset[ln]; !ok {
lset[ln] = lv
}
}
// Encode scrape query parameters as labels.
for k, v := range cfg.Params {
if len(v) > 0 {
lset[model.LabelName(model.ParamLabelPrefix+k)] = model.LabelValue(v[0])
}
}
preRelabelLabels := lset
lset = relabel.Process(lset, cfg.RelabelConfigs...)
// Check if the target was dropped.
if lset == nil {
return nil, nil, nil
}
// addPort checks whether we should add a default port to the address.
// If the address is not valid, we don't append a port either.
addPort := func(s string) bool {
// If we can split, a port exists and we don't have to add one.
if _, _, err := net.SplitHostPort(s); err == nil {
return false
}
// If adding a port makes it valid, the previous error
// was not due to an invalid address and we can append a port.
_, _, err := net.SplitHostPort(s + ":1234")
return err == nil
}
// If it's an address with no trailing port, infer it based on the used scheme.
if addr := string(lset[model.AddressLabel]); addPort(addr) {
// Addresses reaching this point are already wrapped in [] if necessary.
switch lset[model.SchemeLabel] {
case "http", "":
addr = addr + ":80"
case "https":
addr = addr + ":443"
default:
return nil, nil, fmt.Errorf("invalid scheme: %q", cfg.Scheme)
}
lset[model.AddressLabel] = model.LabelValue(addr)
}
if err := config.CheckTargetAddress(lset[model.AddressLabel]); err != nil {
return nil, nil, err
}
// Meta labels are deleted after relabelling. Other internal labels propagate to
// the target which decides whether they will be part of their label set.
for ln := range lset {
if strings.HasPrefix(string(ln), model.MetaLabelPrefix) {
delete(lset, ln)
}
}
// Default the instance label to the target address.
if _, ok := lset[model.InstanceLabel]; !ok {
lset[model.InstanceLabel] = lset[model.AddressLabel]
}
return lset, preRelabelLabels, nil
}
// targetsFromGroup builds targets based on the given TargetGroup and config.
// Panics if target group is nil.
func targetsFromGroup(tg *config.TargetGroup, cfg *config.ScrapeConfig) ([]*Target, error) {
targets := make([]*Target, 0, len(tg.Targets))
for i, labels := range tg.Targets {
for k, v := range cfg.Params {
if len(v) > 0 {
labels[model.LabelName(model.ParamLabelPrefix+k)] = model.LabelValue(v[0])
for i, lset := range tg.Targets {
// Combine target labels with target group labels.
for ln, lv := range tg.Labels {
if _, ok := lset[ln]; !ok {
lset[ln] = lv
}
}
// Copy labels into the labelset for the target if they are not
// set already. Apply the labelsets in order of decreasing precedence.
labelsets := []model.LabelSet{
tg.Labels,
{
model.SchemeLabel: model.LabelValue(cfg.Scheme),
model.MetricsPathLabel: model.LabelValue(cfg.MetricsPath),
model.JobLabel: model.LabelValue(cfg.JobName),
},
labels, origLabels, err := populateLabels(lset, cfg)
if err != nil {
return nil, fmt.Errorf("instance %d in group %s: %s", i, tg, err)
}
for _, lset := range labelsets {
for ln, lv := range lset {
if _, ok := labels[ln]; !ok {
labels[ln] = lv
}
}
if labels != nil {
targets = append(targets, NewTarget(labels, origLabels, cfg.Params))
}
if _, ok := labels[model.AddressLabel]; !ok {
return nil, fmt.Errorf("instance %d in target group %s has no address", i, tg)
}
preRelabelLabels := labels
labels := relabel.Process(labels, cfg.RelabelConfigs...)
// Check if the target was dropped.
if labels == nil {
continue
}
// If no port was provided, infer it based on the used scheme.
addr := string(labels[model.AddressLabel])
if !strings.Contains(addr, ":") {
switch labels[model.SchemeLabel] {
case "http", "":
addr = fmt.Sprintf("%s:80", addr)
case "https":
addr = fmt.Sprintf("%s:443", addr)
default:
return nil, fmt.Errorf("invalid scheme: %q", cfg.Scheme)
}
labels[model.AddressLabel] = model.LabelValue(addr)
}
if err := config.CheckTargetAddress(labels[model.AddressLabel]); err != nil {
return nil, err
}
for ln := range labels {
// Meta labels are deleted after relabelling. Other internal labels propagate to
// the target which decides whether they will be part of their label set.
if strings.HasPrefix(string(ln), model.MetaLabelPrefix) {
delete(labels, ln)
}
}
if _, ok := labels[model.InstanceLabel]; !ok {
labels[model.InstanceLabel] = labels[model.AddressLabel]
}
targets = append(targets, NewTarget(labels, preRelabelLabels, cfg.Params))
}
return targets, nil
}

View file

@ -14,11 +14,13 @@
package retrieval
import (
"reflect"
"testing"
"golang.org/x/net/context"
"gopkg.in/yaml.v2"
"github.com/prometheus/common/model"
"github.com/prometheus/prometheus/config"
"github.com/prometheus/prometheus/storage/local"
)
@ -72,3 +74,135 @@ dns_sd_configs:
verifyPresence(ts.tgroups, "dns/0/srv.name.one.example.org", false)
verifyPresence(ts.tgroups, "dns/0/srv.name.two.example.org", true)
}
func mustNewRegexp(s string) config.Regexp {
re, err := config.NewRegexp(s)
if err != nil {
panic(err)
}
return re
}
func TestPopulateLabels(t *testing.T) {
cases := []struct {
in model.LabelSet
cfg *config.ScrapeConfig
res model.LabelSet
resOrig model.LabelSet
}{
// Regular population of scrape config options.
{
in: model.LabelSet{
model.AddressLabel: "1.2.3.4:1000",
"custom": "value",
},
cfg: &config.ScrapeConfig{
Scheme: "https",
MetricsPath: "/metrics",
JobName: "job",
},
res: model.LabelSet{
model.AddressLabel: "1.2.3.4:1000",
model.InstanceLabel: "1.2.3.4:1000",
model.SchemeLabel: "https",
model.MetricsPathLabel: "/metrics",
model.JobLabel: "job",
"custom": "value",
},
resOrig: model.LabelSet{
model.AddressLabel: "1.2.3.4:1000",
model.SchemeLabel: "https",
model.MetricsPathLabel: "/metrics",
model.JobLabel: "job",
"custom": "value",
},
},
// Pre-define/overwrite scrape config labels.
// Leave out port and expect it to be defaulted to scheme.
{
in: model.LabelSet{
model.AddressLabel: "1.2.3.4",
model.SchemeLabel: "http",
model.MetricsPathLabel: "/custom",
model.JobLabel: "custom-job",
},
cfg: &config.ScrapeConfig{
Scheme: "https",
MetricsPath: "/metrics",
JobName: "job",
},
res: model.LabelSet{
model.AddressLabel: "1.2.3.4:80",
model.InstanceLabel: "1.2.3.4:80",
model.SchemeLabel: "http",
model.MetricsPathLabel: "/custom",
model.JobLabel: "custom-job",
},
resOrig: model.LabelSet{
model.AddressLabel: "1.2.3.4",
model.SchemeLabel: "http",
model.MetricsPathLabel: "/custom",
model.JobLabel: "custom-job",
},
},
// Provide instance label. HTTPS port default for IPv6.
{
in: model.LabelSet{
model.AddressLabel: "[::1]",
model.InstanceLabel: "custom-instance",
},
cfg: &config.ScrapeConfig{
Scheme: "https",
MetricsPath: "/metrics",
JobName: "job",
},
res: model.LabelSet{
model.AddressLabel: "[::1]:443",
model.InstanceLabel: "custom-instance",
model.SchemeLabel: "https",
model.MetricsPathLabel: "/metrics",
model.JobLabel: "job",
},
resOrig: model.LabelSet{
model.AddressLabel: "[::1]",
model.InstanceLabel: "custom-instance",
model.SchemeLabel: "https",
model.MetricsPathLabel: "/metrics",
model.JobLabel: "job",
},
},
// Apply relabeling.
{
in: model.LabelSet{
model.AddressLabel: "1.2.3.4:1000",
"custom": "value",
},
cfg: &config.ScrapeConfig{
Scheme: "https",
MetricsPath: "/metrics",
JobName: "job",
RelabelConfigs: []*config.RelabelConfig{
{
Action: config.RelabelDrop,
Regex: mustNewRegexp(".*"),
SourceLabels: model.LabelNames{"job"},
},
},
},
res: nil,
resOrig: nil,
},
}
for i, c := range cases {
res, orig, err := populateLabels(c.in, c.cfg)
if err != nil {
t.Fatalf("case %d: %s", i, err)
}
if !reflect.DeepEqual(res, c.res) {
t.Errorf("case %d: expected res\n\t%+v\n got\n\t%+v", i, c.res, res)
}
if !reflect.DeepEqual(orig, c.resOrig) {
t.Errorf("case %d: expected resOrig\n\t%+v\n got\n\t%+v", i, c.resOrig, orig)
}
}
}