2dd8a687b3
Stop the caddy message and start our own init notifications. Log the version of CoreDNS when starting up. Fix all middleware's setup functions so that return the error prefixed with *which* middleware was failing; leads to better debuggable errors when starting up.
84 lines
1.5 KiB
Go
84 lines
1.5 KiB
Go
package metrics
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import (
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"sync"
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"github.com/miekg/coredns/core/dnsserver"
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"github.com/miekg/coredns/middleware"
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"github.com/mholt/caddy"
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)
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func init() {
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caddy.RegisterPlugin("prometheus", caddy.Plugin{
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ServerType: "dns",
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Action: setup,
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})
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}
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func setup(c *caddy.Controller) error {
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m, err := prometheusParse(c)
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if err != nil {
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return middleware.Error("prometheus", err)
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}
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dnsserver.GetConfig(c).AddMiddleware(func(next dnsserver.Handler) dnsserver.Handler {
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m.Next = next
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return m
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})
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metricsOnce.Do(func() {
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c.OnStartup(m.Startup)
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c.OnShutdown(m.Shutdown)
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})
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return nil
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}
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func prometheusParse(c *caddy.Controller) (Metrics, error) {
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var (
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met Metrics
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err error
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)
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for c.Next() {
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if len(met.ZoneNames) > 0 {
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return Metrics{}, c.Err("metrics: can only have one metrics module per server")
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}
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met.ZoneNames = make([]string, len(c.ServerBlockKeys))
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copy(met.ZoneNames, c.ServerBlockKeys)
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for i, _ := range met.ZoneNames {
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met.ZoneNames[i] = middleware.Host(met.ZoneNames[i]).Normalize()
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}
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args := c.RemainingArgs()
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switch len(args) {
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case 0:
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case 1:
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met.Addr = args[0]
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default:
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return Metrics{}, c.ArgErr()
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}
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for c.NextBlock() {
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switch c.Val() {
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case "address":
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args = c.RemainingArgs()
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if len(args) != 1 {
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return Metrics{}, c.ArgErr()
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}
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met.Addr = args[0]
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default:
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return Metrics{}, c.Errf("metrics: unknown item: %s", c.Val())
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}
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}
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}
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if met.Addr == "" {
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met.Addr = addr
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}
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return met, err
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}
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var metricsOnce sync.Once
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const addr = "localhost:9153"
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