// Decode job from byte slice
func decodeJob(data []byte) (job *Job, err error) {
if len(data) < 12 {
return nil, common.Errorf("Invalid data: %V", data)
}
datatype := common.BytesToUint32([4]byte{data[4], data[5], data[6], data[7]})
l := common.BytesToUint32([4]byte{data[8], data[9], data[10], data[11]})
if len(data[12:]) != int(l) {
return nil, common.Errorf("Invalid data: %V", data)
}
data = data[12:]
job = &Job{magicCode: common.RES, DataType: datatype, c: make(chan bool)}
switch datatype {
case common.JOB_ASSIGN:
s := bytes.SplitN(data, []byte{'\x00'}, 3)
if len(s) == 3 {
job.Handle = string(s[0])
job.Fn = string(s[1])
data = s[2]
}
case common.JOB_ASSIGN_UNIQ:
s := bytes.SplitN(data, []byte{'\x00'}, 4)
if len(s) == 4 {
job.Handle = string(s[0])
job.Fn = string(s[1])
job.UniqueId = string(s[2])
data = s[3]
}
}
job.Data = data
return
}
// Decode a job from byte slice
func decodeJob(data []byte) (job *Job, err error) {
if len(data) < 12 {
return nil, common.Errorf("Invalid data: %V", data)
}
datatype := common.BytesToUint32([4]byte{data[4], data[5], data[6], data[7]})
l := common.BytesToUint32([4]byte{data[8], data[9], data[10], data[11]})
if len(data[12:]) != int(l) {
return nil, common.Errorf("Invalid data: %V", data)
}
data = data[12:]
var handle string
switch datatype {
case common.WORK_DATA, common.WORK_WARNING, common.WORK_STATUS,
common.WORK_COMPLETE, common.WORK_FAIL, common.WORK_EXCEPTION:
i := bytes.IndexByte(data, '\x00')
if i != -1 {
handle = string(data[:i])
data = data[i+1:]
}
}
return &Job{magicCode: common.RES,
DataType: datatype,
Data: data,
Handle: handle}, nil
}
// Decode a job from byte slice
func decodeJob(data []byte) (job *Job, err error) {
if len(data) < 12 {
return nil, common.Errorf("Invalid data: %V", data)
}
datatype := common.BytesToUint32([4]byte{data[4], data[5], data[6], data[7]})
l := common.BytesToUint32([4]byte{data[8], data[9], data[10], data[11]})
if len(data[12:]) != int(l) {
return nil, common.Errorf("Invalid data: %V", data)
}
data = data[12:]
return newJob(common.RES, datatype, data), nil
}
// inputing loop
func (a *agent) inLoop() {
defer func() {
if r := recover(); r != nil {
a.worker.err(common.Errorf("Exiting: %s", r))
}
close(a.in)
close(a.out)
a.worker.removeAgent(a)
}()
for a.worker.running {
a.WriteJob(newJob(common.REQ, common.PRE_SLEEP, nil))
RESTART:
// got noop msg and in queue is zero, grab job
rel, err := a.read()
if err != nil {
if err == common.ErrConnection {
for i := 0; i < 3 && a.worker.running; i++ {
if conn, err := net.Dial(common.NETWORK, a.addr); err != nil {
a.worker.err(common.Errorf("Reconnection: %d faild", i))
continue
} else {
a.conn = conn
goto RESTART
}
}
a.worker.err(err)
break
}
a.worker.err(err)
continue
}
job, err := decodeJob(rel)
if err != nil {
a.worker.err(err)
continue
}
switch job.DataType {
case common.NOOP:
a.WriteJob(newJob(common.REQ, common.GRAB_JOB_UNIQ, nil))
case common.ERROR, common.ECHO_RES, common.JOB_ASSIGN_UNIQ, common.JOB_ASSIGN:
if a.worker.running {
if a.worker.limit != nil {
a.worker.limit <- true
}
job.agent = a
a.worker.in <- job
}
}
}
}
// Execute the job. And send back the result.
func (worker *Worker) exec(job *Job) (err error) {
defer func() {
if r := recover(); r != nil {
if e, ok := r.(error); ok {
err = e
} else {
err = common.ErrUnknown
}
}
}()
if worker.limit != nil {
<-worker.limit
defer func() {
worker.limit <- true
}()
}
var limit int
if job.DataType == common.JOB_ASSIGN {
limit = 3
} else {
limit = 4
}
jobdata := bytes.SplitN(job.Data, []byte{'\x00'}, limit)
job.Handle = string(jobdata[0])
funcname := string(jobdata[1])
if job.DataType == common.JOB_ASSIGN {
job.Data = jobdata[2]
} else {
job.UniqueId = string(jobdata[2])
job.Data = jobdata[3]
}
f, ok := worker.funcs[funcname]
if !ok {
return common.Errorf("The function does not exist: %s", funcname)
}
var r *result
if f.timeout == 0 {
d, e := f.f(job)
r = &result{data: d, err: e}
} else {
r = execTimeout(f.f, job, time.Duration(f.timeout)*time.Second)
}
var datatype uint32
if r.err == nil {
datatype = common.WORK_COMPLETE
} else {
if r.data == nil {
datatype = common.WORK_FAIL
} else {
datatype = common.WORK_EXCEPTION
}
err = r.err
}
job.magicCode = common.REQ
job.DataType = datatype
job.Data = r.data
job.agent.WriteJob(job)
return
}
// Internal read
func (a *agent) read() (data []byte, err error) {
BEGIN:
inlen := len(a.in)
if inlen > 0 {
// in queue is not empty
for i := 0; i < inlen; i++ {
data = append(data, <-a.in...)
}
} else {
for {
buf := make([]byte, common.BUFFER_SIZE)
var n int
if n, err = a.conn.Read(buf); err != nil {
if err == io.EOF && n == 0 {
if data == nil {
err = common.ErrConnection
return
}
break
}
return
}
data = append(data, buf[0:n]...)
if n < common.BUFFER_SIZE {
break
}
}
}
// split package
tl := len(data)
if tl < 12 { // too few data to unpack, read more
goto BEGIN
}
start := 0
for i := 0; i < tl-11; i++ {
if start+12 > tl { // too few data to unpack, read more
goto BEGIN
}
if string(data[start:start+4]) == common.RES_STR {
l := int(common.BytesToUint32([4]byte{data[start+8],
data[start+9], data[start+10], data[start+11]}))
total := l + 12
if total == tl { // data is what we want
return
} else if total < tl { // data[:total] is what we want, data[total:] is the more
a.in <- data[total:]
data = data[:total]
return
} else { // ops! It won't be possible.
goto BEGIN
}
} else { // flag was not found, move to next step
start++
}
}
goto BEGIN
return nil, common.Errorf("Invalid data: %V", data)
}
// Remove a function.
// Tell job servers 'I can not do this now' at the same time.
func (worker *Worker) RemoveFunc(funcname string) (err error) {
if _, ok := worker.funcs[funcname]; !ok {
return common.Errorf("The function does not exist: %s", funcname)
}
delete(worker.funcs, funcname)
if worker.running {
worker.removeFunc(funcname)
}
return
}
// Add a function.
// Plz added job servers first, then functions.
// The API will tell every connected job server that 'I can do this'
func (worker *Worker) AddFunc(funcname string,
f JobFunc, timeout uint32) (err error) {
if _, ok := worker.funcs[funcname]; ok {
return common.Errorf("The function already exists: %s", funcname)
}
worker.funcs[funcname] = &jobFunc{f: f, timeout: timeout}
if worker.running {
worker.addFunc(funcname, timeout)
}
return
}
// status handler
func (client *Client) handleStatus(job *Job) {
data := bytes.SplitN(job.Data, []byte{'\x00'}, 5)
if len(data) != 5 {
client.err(common.Errorf("Invalid data: %V", job.Data))
return
}
status := &Status{}
status.Handle = string(data[0])
status.Known = (data[1][0] == '1')
status.Running = (data[2][0] == '1')
var err error
status.Numerator, err = strconv.ParseUint(string(data[3][0]), 10, 0)
if err != nil {
client.err(common.Errorf("Invalid handle: %s", data[3][0]))
return
}
status.Denominator, err = strconv.ParseUint(string(data[4][0]), 10, 0)
if err != nil {
client.err(common.Errorf("Invalid handle: %s", data[4][0]))
return
}
client.status <- status
}
// status handler
func (client *Client) handleStatus(job *Job) {
if client.StatusHandler != nil {
data := bytes.SplitN(job.Data, []byte{'\x00'}, 5)
if len(data) != 5 {
client.err(common.Errorf("Invalid data: %V", job.Data))
return
}
handle := string(data[0])
known := (data[1][0] == '1')
running := (data[2][0] == '1')
numerator, err := strconv.ParseUint(string(data[3][0]), 10, 0)
if err != nil {
client.err(common.Errorf("Invalid handle: %s", data[3][0]))
return
}
denominator, err := strconv.ParseUint(string(data[4][0]), 10, 0)
if err != nil {
client.err(common.Errorf("Invalid handle: %s", data[4][0]))
return
}
client.StatusHandler(handle, known, running, numerator, denominator)
}
}
// inner read
func (client *Client) read() (data []byte, err error) {
if len(client.in) > 0 {
// incoming queue is not empty
data = <-client.in
} else {
// empty queue, read data from socket
for {
buf := make([]byte, common.BUFFER_SIZE)
var n int
if n, err = client.conn.Read(buf); err != nil {
if err == io.EOF && n == 0 {
if data == nil {
err = common.ErrConnection
return
}
break
}
return
}
data = append(data, buf[0:n]...)
if n < common.BUFFER_SIZE {
break
}
}
}
// split package
tl := len(data)
start, end := 0, 4
for i := 0; i < tl; i++ {
if string(data[start:end]) == common.RES_STR {
l := int(common.BytesToUint32([4]byte{data[start+8], data[start+9], data[start+10], data[start+11]}))
total := l + 12
if total == tl {
return
} else {
client.in <- data[total:]
data = data[:total]
return
}
} else {
start++
end++
}
}
return nil, common.Errorf("Invalid data: %V", data)
}
// Extract the job's result.
func (job *Job) Result() (data []byte, err error) {
switch job.DataType {
case common.WORK_FAIL:
job.Handle = string(job.Data)
return nil, common.ErrWorkFail
case common.WORK_EXCEPTION:
err = common.ErrWorkException
fallthrough
case common.WORK_COMPLETE:
s := bytes.SplitN(job.Data, []byte{'\x00'}, 2)
if len(s) != 2 {
return nil, common.Errorf("Invalid data: %V", job.Data)
}
job.Handle = string(s[0])
data = s[1]
default:
err = common.ErrDataType
}
return
}
// Execute the job. And send back the result.
func (worker *Worker) exec(job *Job) (err error) {
defer func() {
if r := recover(); r != nil {
if e, ok := r.(error); ok {
err = e
} else {
err = common.ErrUnknown
}
}
}()
f, ok := worker.funcs[job.Fn]
if !ok {
return common.Errorf("The function does not exist: %s", job.Fn)
}
var r *result
if f.timeout == 0 {
d, e := f.f(job)
r = &result{data: d, err: e}
} else {
r = execTimeout(f.f, job, time.Duration(f.timeout)*time.Second)
}
var datatype uint32
if r.err == nil {
datatype = common.WORK_COMPLETE
} else {
if r.data == nil {
datatype = common.WORK_FAIL
} else {
datatype = common.WORK_EXCEPTION
}
err = r.err
}
job.magicCode = common.REQ
job.DataType = datatype
job.Data = r.data
if worker.running {
job.agent.WriteJob(job)
}
return
}