Extract bind statistics parsing in sub-packages

This prepares the addition of statistics v3 parsing.

bind/client.go

@@ -0,0 +1,60 @@
+package bind
+
+// Client queries the BIND API, parses the response and returns stats in a
+// generic format.
+type Client interface {
+	Stats() (Statistics, error)
+}
+
+// Common bind field types.
+const (
+	QryRTT = "QryRTT"
+)
+
+// Statistics is a generic representation of BIND statistics.
+type Statistics struct {
+	Server struct {
+		IncomingQueries  []Stat
+		IncomingRequests []Stat
+		NSStats          []Stat
+	}
+	Views       []View
+	TaskManager TaskManager
+}
+
+// View represents a statistics for a single BIND view.
+type View struct {
+	Name            string
+	Cache           []Stat
+	ResolverStats   []Stat
+	ResolverQueries []Stat
+}
+
+// Stat represents a single counter value.
+type Stat struct {
+	Name    string
+	Counter uint
+}
+
+// Task represents a single running task.
+type Task struct {
+	ID         string `xml:"id"`
+	Name       string `xml:"name"`
+	Quantum    uint   `xml:"quantum"`
+	References uint   `xml:"references"`
+	State      string `xml:"state"`
+}
+
+// TaskManager contains information about all running tasks.
+type TaskManager struct {
+	Tasks       []Task      `xml:"tasks>task"`
+	ThreadModel ThreadModel `xml:"thread-model"`
+}
+
+// ThreadModel contains task and worker information.
+type ThreadModel struct {
+	Type           string `xml:"type"`
+	WorkerThreads  uint   `xml:"worker-threads"`
+	DefaultQuantum uint   `xml:"default-quantum"`
+	TasksRunning   uint   `xml:"tasks-running"`
+}

bind/v2/struct.go

@@ -0,0 +1,71 @@
+package v2
+
+import (
+	"encoding/xml"
+
+	"github.com/digitalocean/bind_exporter/bind"
+)
+
+type Zone struct {
+	Name       string `xml:"name"`
+	Rdataclass string `xml:"rdataclass"`
+	Serial     string `xml:"serial"`
+}
+
+type Stat struct {
+	Name    string `xml:"name"`
+	Counter uint   `xml:"counter"`
+}
+
+type View struct {
+	Name    string `xml:"name"`
+	Cache   []Stat `xml:"cache>rrset"`
+	Rdtype  []Stat `xml:"rdtype"`
+	Resstat []Stat `xml:"resstat"`
+	Zones   []Zone `xml:"zones>zone"`
+}
+
+//TODO expand
+type Socket struct {
+	ID           string `xml:"id"`
+	Name         string `xml:"name"`
+	LocalAddress string `xml:"local-address"`
+	References   uint   `xml:"references"`
+}
+
+type Socketmgr struct {
+	References uint     `xml:"references"`
+	Sockets    []Socket `xml:"sockets>socket"`
+}
+
+type QueriesIn struct {
+	Rdtype []Stat `xml:"rdtype"`
+}
+
+type Requests struct {
+	Opcode []Stat `xml:"opcode"`
+}
+
+type Server struct {
+	Requests  Requests  `xml:"requests"`
+	QueriesIn QueriesIn `xml:"queries-in"`
+
+	NsStats     []Stat `xml:"nsstat"`
+	SocketStats []Stat `xml:"socketstat"`
+	ZoneStats   []Stat `xml:"zonestats"`
+}
+
+type Statistics struct {
+	Views     []View           `xml:"views>view"`
+	Socketmgr Socketmgr        `xml:"socketmgr"`
+	Taskmgr   bind.TaskManager `xml:"taskmgr"`
+	Server    Server           `xml:"server"`
+	Memory    struct{}         `xml:"memory"`
+}
+type Bind struct {
+	Statistics Statistics `xml:"statistics"`
+}
+type Isc struct {
+	XMLName xml.Name `xml:"isc"`
+	Bind    Bind     `xml:"bind"`
+}

bind/v2/v2.go

@@ -0,0 +1,79 @@
+package v2
+
+import (
+	"encoding/xml"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/digitalocean/bind_exporter/bind"
+)
+
+// Client implements bind.Client and can be used to query a BIND v2 API.
+type Client struct {
+	url  string
+	http *http.Client
+}
+
+// NewClient returns an initialized Client.
+func NewClient(url string, c *http.Client) *Client {
+	return &Client{
+		url:  url,
+		http: c,
+	}
+}
+
+// Stats implements bind.Stats.
+func (c *Client) Stats() (bind.Statistics, error) {
+	s := bind.Statistics{}
+
+	resp, err := c.http.Get(c.url)
+	if err != nil {
+		return s, fmt.Errorf("error querying stats: %s", err)
+	}
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return s, fmt.Errorf("failed to read response: %s", err)
+	}
+
+	root := Isc{}
+	if err := xml.Unmarshal([]byte(body), &root); err != nil {
+		return s, fmt.Errorf("Failed to unmarshal XML response: %s", err)
+	}
+
+	stats := root.Bind.Statistics
+	for _, t := range stats.Server.QueriesIn.Rdtype {
+		s.Server.IncomingQueries = append(s.Server.IncomingQueries, stat(t))
+	}
+	for _, t := range stats.Server.Requests.Opcode {
+		s.Server.IncomingRequests = append(s.Server.IncomingRequests, stat(t))
+	}
+	for _, t := range stats.Server.NsStats {
+		s.Server.NSStats = append(s.Server.NSStats, stat(t))
+	}
+	for _, view := range stats.Views {
+		v := bind.View{Name: view.Name}
+		for _, t := range view.Cache {
+			v.Cache = append(v.Cache, stat(t))
+		}
+		for _, t := range view.Rdtype {
+			v.ResolverQueries = append(v.ResolverQueries, stat(t))
+		}
+		for _, t := range view.Resstat {
+			v.ResolverStats = append(v.ResolverStats, stat(t))
+		}
+		s.Views = append(s.Views, v)
+	}
+	s.TaskManager = stats.Taskmgr
+
+	return s, nil
+}
+
+func stat(s Stat) bind.Stat {
+	return bind.Stat{
+		Name:    s.Name,
+		Counter: s.Counter,
+	}
+}