Add HTTP(s) Subscriptions

CHANGELOG.md

@@ -16,6 +16,7 @@
 - [#2926](https://github.com/influxdata/influxdb/issues/2926): Support bound parameters in the parser.
 - [#1310](https://github.com/influxdata/influxdb/issues/1310): Add https-private-key option to httpd config.
 - [#6621](https://github.com/influxdata/influxdb/pull/6621): Add Holt-Winter forecasting function.
+- [#6655](https://github.com/influxdata/influxdb/issues/6655): Add HTTP(s) based subscriptions.
 
 ### Bugfixes
 

cmd/influxd/run/config.go

@@ -168,6 +168,10 @@ func (c *Config) Validate() error {
 		return err
 	}
 
+	if err := c.Subscriber.Validate(); err != nil {
+		return err
+	}
+
 	for _, g := range c.GraphiteInputs {
 		if err := g.Validate(); err != nil {
 			return fmt.Errorf("invalid graphite config: %v", err)

etc/config.sample.toml

@@ -172,6 +172,18 @@ reporting-disabled = false
   # https-private-key = ""
   max-row-limit = 10000
 
+###
+### [subsciber]
+###
+### Controls the subscriptions, which can be used to fork a copy of all data
+### received by the InfluxDB host.
+###
+
+[subsciber]
+  enabled = true
+  http-timeout = "30s"
+
+
 ###
 ### [[graphite]]
 ###

services/subscriber/config.go

@@ -1,12 +1,35 @@
 package subscriber
 
+import (
+	"errors"
+	"time"
+
+	"github.com/influxdata/influxdb/toml"
+)
+
+const (
+	DefaultHTTPTimeout = 30 * time.Second
+)
+
 // Config represents a configuration of the subscriber service.
 type Config struct {
 	// Whether to enable to Subscriber service
 	Enabled bool `toml:"enabled"`
+
+	HTTPTimeout toml.Duration `toml:"http-timeout"`
 }
 
 // NewConfig returns a new instance of a subscriber config.
 func NewConfig() Config {
-	return Config{Enabled: true}
+	return Config{
+		Enabled:     true,
+		HTTPTimeout: toml.Duration(DefaultHTTPTimeout),
+	}
+}
+
+func (c Config) Validate() error {
+	if c.HTTPTimeout <= 0 {
+		return errors.New("http-timeout must be greater than 0")
+	}
+	return nil
 }

services/subscriber/http.go

@@ -0,0 +1,39 @@
+package subscriber
+
+import (
+	"time"
+
+	"github.com/influxdata/influxdb/client/v2"
+	"github.com/influxdata/influxdb/coordinator"
+)
+
+// HTTP supports writing points over HTTP using the line protocol.
+type HTTP struct {
+	c client.Client
+}
+
+// NewHTTP returns a new HTTP points writer with default options.
+func NewHTTP(addr string, timeout time.Duration) (*HTTP, error) {
+	conf := client.HTTPConfig{
+		Addr:    addr,
+		Timeout: timeout,
+	}
+	c, err := client.NewHTTPClient(conf)
+	if err != nil {
+		return nil, err
+	}
+	return &HTTP{c: c}, nil
+}
+
+// WritePoints writes points over HTTP transport.
+func (h *HTTP) WritePoints(p *coordinator.WritePointsRequest) (err error) {
+	bp, _ := client.NewBatchPoints(client.BatchPointsConfig{
+		Database:        p.Database,
+		RetentionPolicy: p.RetentionPolicy,
+	})
+	for _, pt := range p.Points {
+		bp.AddPoint(client.NewPointFrom(pt))
+	}
+	err = h.c.Write(bp)
+	return
+}