1 files changed, 213 insertions, 0 deletions
diff --git a/src/go/pkg/netdataapi/api.go b/src/go/pkg/netdataapi/api.go
new file mode 100644
index 000000000..4f3faefc8
--- /dev/null
+++ b/src/go/pkg/netdataapi/api.go
@@ -0,0 +1,213 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package netdataapi
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"strconv"
+)
+
+type (
+	// API implements Netdata external plugins API.
+	// https://learn.netdata.cloud/docs/agent/plugins.d#the-output-of-the-plugin
+	API struct {
+		io.Writer
+	}
+)
+
+const quotes = "' '"
+
+var (
+	end          = []byte("END\n\n")
+	clabelCommit = []byte("CLABEL_COMMIT\n")
+	newLine      = []byte("\n")
+)
+
+func New(w io.Writer) *API { return &API{w} }
+
+// CHART  creates or update a chart.
+func (a *API) CHART(
+	typeID string,
+	ID string,
+	name string,
+	title string,
+	units string,
+	family string,
+	context string,
+	chartType string,
+	priority int,
+	updateEvery int,
+	options string,
+	plugin string,
+	module string) error {
+	_, err := a.Write([]byte("CHART " + "'" +
+		typeID + "." + ID + quotes +
+		name + quotes +
+		title + quotes +
+		units + quotes +
+		family + quotes +
+		context + quotes +
+		chartType + quotes +
+		strconv.Itoa(priority) + quotes +
+		strconv.Itoa(updateEvery) + quotes +
+		options + quotes +
+		plugin + quotes +
+		module + "'\n"))
+	return err
+}
+
+// DIMENSION adds or update a dimension to the chart just created.
+func (a *API) DIMENSION(
+	ID string,
+	name string,
+	algorithm string,
+	multiplier int,
+	divisor int,
+	options string) error {
+	_, err := a.Write([]byte("DIMENSION '" +
+		ID + quotes +
+		name + quotes +
+		algorithm + quotes +
+		strconv.Itoa(multiplier) + quotes +
+		strconv.Itoa(divisor) + quotes +
+		options + "'\n"))
+	return err
+}
+
+// CLABEL adds or update a label to the chart.
+func (a *API) CLABEL(key, value string, source int) error {
+	_, err := a.Write([]byte("CLABEL '" +
+		key + quotes +
+		value + quotes +
+		strconv.Itoa(source) + "'\n"))
+	return err
+}
+
+// CLABELCOMMIT adds labels to the chart. Should be called after one or more CLABEL.
+func (a *API) CLABELCOMMIT() error {
+	_, err := a.Write(clabelCommit)
+	return err
+}
+
+// BEGIN initializes data collection for a chart.
+func (a *API) BEGIN(typeID string, ID string, msSince int) (err error) {
+	if msSince > 0 {
+		_, err = a.Write([]byte("BEGIN " + "'" + typeID + "." + ID + "' " + strconv.Itoa(msSince) + "\n"))
+	} else {
+		_, err = a.Write([]byte("BEGIN " + "'" + typeID + "." + ID + "'\n"))
+	}
+	return err
+}
+
+// SET sets the value of a dimension for the initialized chart.
+func (a *API) SET(ID string, value int64) error {
+	_, err := a.Write([]byte("SET '" + ID + "' = " + strconv.FormatInt(value, 10) + "\n"))
+	return err
+}
+
+// SETEMPTY sets the empty value of a dimension for the initialized chart.
+func (a *API) SETEMPTY(ID string) error {
+	_, err := a.Write([]byte("SET '" + ID + "' = \n"))
+	return err
+}
+
+// VARIABLE sets the value of a CHART scope variable for the initialized chart.
+func (a *API) VARIABLE(ID string, value int64) error {
+	_, err := a.Write([]byte("VARIABLE CHART '" + ID + "' = " + strconv.FormatInt(value, 10) + "\n"))
+	return err
+}
+
+// END completes data collection for the initialized chart.
+func (a *API) END() error {
+	_, err := a.Write(end)
+	return err
+}
+
+// DISABLE disables this plugin. This will prevent Netdata from restarting the plugin.
+func (a *API) DISABLE() error {
+	_, err := a.Write([]byte("DISABLE\n"))
+	return err
+}
+
+// EMPTYLINE writes an empty line.
+func (a *API) EMPTYLINE() error {
+	_, err := a.Write(newLine)
+	return err
+}
+
+func (a *API) HOSTINFO(guid, hostname string, labels map[string]string) error {
+	if err := a.HOSTDEFINE(guid, hostname); err != nil {
+		return err
+	}
+	for k, v := range labels {
+		if err := a.HOSTLABEL(k, v); err != nil {
+			return err
+		}
+	}
+	return a.HOSTDEFINEEND()
+}
+
+func (a *API) HOSTDEFINE(guid, hostname string) error {
+	_, err := fmt.Fprintf(a, "HOST_DEFINE '%s' '%s'\n", guid, hostname)
+	return err
+}
+
+func (a *API) HOSTLABEL(name, value string) error {
+	_, err := fmt.Fprintf(a, "HOST_LABEL '%s' '%s'\n", name, value)
+	return err
+}
+
+func (a *API) HOSTDEFINEEND() error {
+	_, err := fmt.Fprintf(a, "HOST_DEFINE_END\n\n")
+	return err
+}
+
+func (a *API) HOST(guid string) error {
+	_, err := a.Write([]byte("HOST " + "'" +
+		guid + "'\n\n"))
+	return err
+}
+
+func (a *API) FUNCRESULT(uid, contentType, payload, code, expireTimestamp string) {
+	var buf bytes.Buffer
+
+	buf.WriteString("FUNCTION_RESULT_BEGIN " +
+		uid + " " +
+		code + " " +
+		contentType + " " +
+		expireTimestamp + "\n",
+	)
+
+	if payload != "" {
+		buf.WriteString(payload + "\n")
+	}
+
+	buf.WriteString("FUNCTION_RESULT_END\n\n")
+
+	_, _ = buf.WriteTo(a)
+}
+
+func (a *API) CONFIGCREATE(id, status, configType, path, sourceType, source, supportedCommands string) {
+	// https://learn.netdata.cloud/docs/contributing/external-plugins/#config
+
+	_, _ = a.Write([]byte("CONFIG " +
+		id + " " +
+		"create" + " " +
+		status + " " +
+		configType + " " +
+		path + " " +
+		sourceType + " '" +
+		source + "' '" +
+		supportedCommands + "' 0x0000 0x0000\n\n",
+	))
+}
+
+func (a *API) CONFIGDELETE(id string) {
+	_, _ = a.Write([]byte("CONFIG " + id + " delete\n\n"))
+}
+
+func (a *API) CONFIGSTATUS(id, status string) {
+	_, _ = a.Write([]byte("CONFIG " + id + " status " + status + "\n\n"))
+}