triggers.go

package watcher

import (
	"encoding/json"
	"io/ioutil"
	"log"
	"os"
	"os/exec"
	"path/filepath"
	"strings"

	"git.autistici.org/ai3/tools/replds2/common"
	pb "git.autistici.org/ai3/tools/replds2/proto"
)

// The nullTriggerManager does nothing.
type nullTriggerManager struct{}

func (nullTriggerManager) Has(string) bool { return false }

func (nullTriggerManager) Notify(*common.NotifyBatch) {}

// The scriptTriggerManager runs user-configured trigger scripts.
type scriptTriggerManager map[string]*scriptTrigger

func (m scriptTriggerManager) Has(path string) bool {
	_, ok := m[path]
	return ok
}

func (m scriptTriggerManager) Notify(b *common.NotifyBatch) {
	b.Apply(func(path string, nodes []*pb.Node) {
		trigger := m[path]
		if err := trigger.Run(nodes); err != nil {
			log.Printf("trigger error: %v", err)
		}
	})
}

type scriptTrigger struct {
	name string

	Path    string `json:"path"`
	Command string `json:"command"`
}

func (t *scriptTrigger) Run(nodes []*pb.Node) error {
	// Build an environment for the script.
	changedEnvStr := "REPLDS_CHANGES="
	for _, node := range nodes {
		if !node.Deleted {
			changedEnvStr += node.Path
		}
	}

	env := os.Environ()
	env = append(env, "REPLDS=1")
	env = append(env, changedEnvStr)

	// Run the command using the shell.
	cmd := exec.Command("/bin/sh", "-c", t.Command)
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stdout
	cmd.Env = env

	log.Printf("executing trigger '%s'", t.name)

	return cmd.Run()
}