feat(agent/sd): add support HTTP service discovery

docs/sources/operators-guide/configure/reference-configuration-parameters/index.md

@@ -1246,6 +1246,10 @@ static_configs:
 kubernetes_sd_configs:
    [ - <kubernetes_sd_config> ... ]
 
+# List of HTTP service discovery configurations.
+http_sd_configs:
+   [ - <http_sd_config> ... ]
+
 # Sets the `Authorization` header on every scrape request with the
 # configured username and password.
 # password and password_file are mutually exclusive.

docs/sources/operators-guide/configure/reference-configuration-parameters/index.template

@@ -100,6 +100,10 @@ static_configs:
 kubernetes_sd_configs:
    [ - <kubernetes_sd_config> ... ]
 
+# List of HTTP service discovery configurations.
+http_sd_configs:
+   [ - <http_sd_config> ... ]
+
 # Sets the `Authorization` header on every scrape request with the
 # configured username and password.
 # password and password_file are mutually exclusive.

pkg/agent/config.go

@@ -7,6 +7,8 @@ import (
 	"path/filepath"
 	"time"
 
+	"github.com/prometheus/prometheus/discovery/http"
+
 	"github.com/grafana/dskit/flagext"
 	"github.com/parca-dev/parca/pkg/config"
 	parcaconfig "github.com/parca-dev/parca/pkg/config"
@@ -139,6 +141,7 @@ func (c *ScrapeConfig) Validate() error {
 type ServiceDiscoveryConfig struct {
 	StaticConfigs       discovery.StaticConfig `yaml:"static_configs"`
 	KubernetesSDConfigs []*kubernetes.SDConfig `yaml:"kubernetes_sd_configs,omitempty"`
+	HTTPSDConfigs       []*http.SDConfig       `yaml:"http_sd_configs,omitempty"`
 }
 
 func (cfg ServiceDiscoveryConfig) Configs() (res discovery.Configs) {
@@ -148,5 +151,8 @@ func (cfg ServiceDiscoveryConfig) Configs() (res discovery.Configs) {
 	for _, x := range cfg.KubernetesSDConfigs {
 		res = append(res, x)
 	}
+	for _, x := range cfg.HTTPSDConfigs {
+		res = append(res, x)
+	}
 	return res
 }