1 files changed, 71 insertions, 0 deletions
diff --git a/plugin/metadata/setup.go b/plugin/metadata/setup.go
new file mode 100644
index 000000000..33a153a2c
--- /dev/null
+++ b/plugin/metadata/setup.go
@@ -0,0 +1,71 @@
+package metadata
+
+import (
+	"fmt"
+
+	"github.com/coredns/coredns/core/dnsserver"
+	"github.com/coredns/coredns/plugin"
+
+	"github.com/mholt/caddy"
+)
+
+func init() {
+	caddy.RegisterPlugin("metadata", caddy.Plugin{
+		ServerType: "dns",
+		Action:     setup,
+	})
+}
+
+func setup(c *caddy.Controller) error {
+	m, err := metadataParse(c)
+	if err != nil {
+		return err
+	}
+	dnsserver.GetConfig(c).AddPlugin(func(next plugin.Handler) plugin.Handler {
+		m.Next = next
+		return m
+	})
+
+	c.OnStartup(func() error {
+		plugins := dnsserver.GetConfig(c).Handlers()
+		// Collect all plugins which implement Provider interface
+		metadataVariables := map[string]bool{}
+		for _, p := range plugins {
+			if met, ok := p.(Provider); ok {
+				for _, varName := range met.MetadataVarNames() {
+					if _, ok := metadataVariables[varName]; ok {
+						return fmt.Errorf("Metadata variable '%v' has duplicates", varName)
+					}
+					metadataVariables[varName] = true
+				}
+				m.Providers = append(m.Providers, met)
+			}
+		}
+		return nil
+	})
+
+	return nil
+}
+
+func metadataParse(c *caddy.Controller) (*Metadata, error) {
+	m := &Metadata{}
+	c.Next()
+	zones := c.RemainingArgs()
+
+	if len(zones) != 0 {
+		m.Zones = zones
+		for i := 0; i < len(m.Zones); i++ {
+			m.Zones[i] = plugin.Host(m.Zones[i]).Normalize()
+		}
+	} else {
+		m.Zones = make([]string, len(c.ServerBlockKeys))
+		for i := 0; i < len(c.ServerBlockKeys); i++ {
+			m.Zones[i] = plugin.Host(c.ServerBlockKeys[i]).Normalize()
+		}
+	}
+
+	if c.NextBlock() || c.Next() {
+		return nil, plugin.Error("metadata", c.ArgErr())
+	}
+	return m, nil
+}