spongy/spongy.cgi/network.go

162 lines
2.8 KiB
Go

package main
import (
"bufio"
"fmt"
"github.com/go-fsnotify/fsnotify"
"io/ioutil"
"os"
"path"
"strings"
"time"
)
type Network struct {
running bool
name string
currentLog string
lineno int64
basePath string
seq int
}
func NewNetwork(basePath string) (*Network) {
return &Network{
running: true,
name: path.Base(basePath),
basePath: basePath,
}
}
func (nw *Network) Close() {
nw.running = false
}
func (nw *Network) LastEventId() string {
return fmt.Sprintf("%s/%s/%d", nw.name, nw.currentLog, nw.lineno)
}
func (nw *Network) SetPosition(filename string, lineno int64) {
nw.currentLog = filename
nw.lineno = lineno
}
func (nw *Network) errmsg(err error) []string {
s := fmt.Sprintf("ERROR: %s", err.Error())
return []string{s}
}
func (nw *Network) Tail(out chan<- []string) {
if nw.currentLog == "" {
var err error
currentfn := path.Join(nw.basePath, "log", "current")
nw.currentLog, err = os.Readlink(currentfn)
if err != nil {
out <- nw.errmsg(err)
return
}
}
filepath := path.Join(nw.basePath, "log", nw.currentLog)
f, err := os.Open(filepath)
if err != nil {
out <- nw.errmsg(err)
return
}
defer f.Close()
watcher, err := fsnotify.NewWatcher()
if err != nil {
out <- nw.errmsg(err)
return
}
defer watcher.Close()
watcher.Add(filepath)
lineno := int64(0)
// XXX: some way to stop this?
for nw.running {
bf := bufio.NewScanner(f)
lines := make([]string, 0)
for bf.Scan() {
lineno += 1
if lineno <= nw.lineno {
continue
} else {
nw.lineno = lineno
}
t := bf.Text()
// XXX: Consider omitting PING and PONG
parts := strings.Split(t, " ")
if (len(parts) >= 4) && (parts[2] == "NEXTLOG") {
watcher.Remove(filepath)
filename := parts[3]
filepath = path.Join(nw.basePath, "log", filename)
f.Close()
f, err = os.Open(filepath)
if err != nil {
out <- nw.errmsg(err)
return
}
watcher.Add(filepath)
lineno = 0
nw.lineno = 0
}
lines = append(lines, t)
}
if len(lines) > 0 {
out <- lines
}
select {
case _ = <-watcher.Events:
// Somethin' happened!
case err := <-watcher.Errors:
out <- nw.errmsg(err)
return
}
}
}
func (nw *Network) Write(data []byte) {
epoch := time.Now().Unix()
pid := os.Getpid()
filename := fmt.Sprintf("%d-%d-%d.txt", epoch, pid, nw.seq)
filepath := path.Join(nw.basePath, "outq", filename)
ioutil.WriteFile(filepath, data, 0750)
nw.seq += 1
}
func Networks(basePath string) (found []*Network) {
dir, err := os.Open(basePath)
if err != nil {
return
}
defer dir.Close()
entities, _ := dir.Readdirnames(0)
for _, fn := range entities {
netdir := path.Join(basePath, fn)
_, err = os.Stat(path.Join(netdir, "nick"))
if err != nil {
continue
}
nw := NewNetwork(netdir)
found = append(found, nw)
}
return
}