85 lines
1.5 KiB
Go
85 lines
1.5 KiB
Go
package upstream
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import (
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"log"
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"github.com/coredns/coredns/core/dnsserver"
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"github.com/coredns/coredns/plugin"
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"github.com/mholt/caddy"
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)
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func init() {
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caddy.RegisterPlugin("upstream", 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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// Read the configuration and initialize upstreams
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func setup(c *caddy.Controller) error {
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p, err := setupPlugin(c)
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if err != nil {
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return err
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}
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config := dnsserver.GetConfig(c)
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config.AddPlugin(func(next plugin.Handler) plugin.Handler {
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p.Next = next
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return p
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})
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c.OnShutdown(p.onShutdown)
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return nil
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}
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// Read the configuration
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func setupPlugin(c *caddy.Controller) (*UpstreamPlugin, error) {
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p := New()
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log.Println("Initializing the Upstream plugin")
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bootstrap := ""
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upstreamUrls := []string{}
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for c.Next() {
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args := c.RemainingArgs()
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if len(args) > 0 {
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upstreamUrls = append(upstreamUrls, args...)
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}
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for c.NextBlock() {
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switch c.Val() {
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case "bootstrap":
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if !c.NextArg() {
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return nil, c.ArgErr()
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}
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bootstrap = c.Val()
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}
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}
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}
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for _, url := range upstreamUrls {
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u, err := NewUpstream(url, bootstrap)
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if err != nil {
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log.Printf("Cannot initialize upstream %s", url)
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return nil, err
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}
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p.Upstreams = append(p.Upstreams, u)
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}
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return p, nil
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}
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func (p *UpstreamPlugin) onShutdown() error {
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for i := range p.Upstreams {
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u := p.Upstreams[i]
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err := u.Close()
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if err != nil {
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log.Printf("Error while closing the upstream: %s", err)
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}
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}
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return nil
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}
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