open-nomad/command/agent/alloc_endpoint.go
Danielle Lancashire ae8bb7365a
alloc-lifecycle: Fix restart with empty body
Currently when you submit a manual request to the alloc lifecycle API
with a version of Curl that will submit empty bodies, the alloc restart
api will fail with an EOF error.

This behaviour is undesired, as it is reasonable to not submit a body at
all when restarting an entire allocation rather than an individual task.

This fixes it by ignoring EOF (not unexpected EOF) errors and treating
them as entire task restarts.
2019-06-12 15:35:00 +02:00

543 lines
15 KiB
Go

package agent
import (
"context"
"encoding/json"
"fmt"
"io"
"net"
"net/http"
"strconv"
"strings"
"github.com/golang/snappy"
"github.com/gorilla/websocket"
cstructs "github.com/hashicorp/nomad/client/structs"
"github.com/hashicorp/nomad/nomad/structs"
"github.com/hashicorp/nomad/plugins/drivers"
"github.com/ugorji/go/codec"
)
const (
allocNotFoundErr = "allocation not found"
resourceNotFoundErr = "resource not found"
)
func (s *HTTPServer) AllocsRequest(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
if req.Method != "GET" {
return nil, CodedError(405, ErrInvalidMethod)
}
args := structs.AllocListRequest{}
if s.parse(resp, req, &args.Region, &args.QueryOptions) {
return nil, nil
}
var out structs.AllocListResponse
if err := s.agent.RPC("Alloc.List", &args, &out); err != nil {
return nil, err
}
setMeta(resp, &out.QueryMeta)
if out.Allocations == nil {
out.Allocations = make([]*structs.AllocListStub, 0)
}
for _, alloc := range out.Allocations {
alloc.SetEventDisplayMessages()
}
return out.Allocations, nil
}
func (s *HTTPServer) AllocSpecificRequest(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
reqSuffix := strings.TrimPrefix(req.URL.Path, "/v1/allocation/")
// tokenize the suffix of the path to get the alloc id and find the action
// invoked on the alloc id
tokens := strings.Split(reqSuffix, "/")
if len(tokens) > 2 || len(tokens) < 1 {
return nil, CodedError(404, resourceNotFoundErr)
}
allocID := tokens[0]
if len(tokens) == 1 {
return s.allocGet(allocID, resp, req)
}
switch tokens[1] {
case "stop":
return s.allocStop(allocID, resp, req)
}
return nil, CodedError(404, resourceNotFoundErr)
}
func (s *HTTPServer) allocGet(allocID string, resp http.ResponseWriter, req *http.Request) (interface{}, error) {
if req.Method != "GET" {
return nil, CodedError(405, ErrInvalidMethod)
}
args := structs.AllocSpecificRequest{
AllocID: allocID,
}
if s.parse(resp, req, &args.Region, &args.QueryOptions) {
return nil, nil
}
var out structs.SingleAllocResponse
if err := s.agent.RPC("Alloc.GetAlloc", &args, &out); err != nil {
return nil, err
}
setMeta(resp, &out.QueryMeta)
if out.Alloc == nil {
return nil, CodedError(404, "alloc not found")
}
// Decode the payload if there is any
alloc := out.Alloc
if alloc.Job != nil && len(alloc.Job.Payload) != 0 {
decoded, err := snappy.Decode(nil, alloc.Job.Payload)
if err != nil {
return nil, err
}
alloc = alloc.Copy()
alloc.Job.Payload = decoded
}
alloc.SetEventDisplayMessages()
return alloc, nil
}
func (s *HTTPServer) allocStop(allocID string, resp http.ResponseWriter, req *http.Request) (interface{}, error) {
if !(req.Method == "POST" || req.Method == "PUT") {
return nil, CodedError(405, ErrInvalidMethod)
}
sr := &structs.AllocStopRequest{
AllocID: allocID,
}
s.parseWriteRequest(req, &sr.WriteRequest)
var out structs.AllocStopResponse
err := s.agent.RPC("Alloc.Stop", &sr, &out)
return &out, err
}
func (s *HTTPServer) ClientAllocRequest(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
reqSuffix := strings.TrimPrefix(req.URL.Path, "/v1/client/allocation/")
// tokenize the suffix of the path to get the alloc id and find the action
// invoked on the alloc id
tokens := strings.Split(reqSuffix, "/")
if len(tokens) != 2 {
return nil, CodedError(404, resourceNotFoundErr)
}
allocID := tokens[0]
switch tokens[1] {
case "stats":
return s.allocStats(allocID, resp, req)
case "exec":
return s.allocExec(allocID, resp, req)
case "snapshot":
if s.agent.client == nil {
return nil, clientNotRunning
}
return s.allocSnapshot(allocID, resp, req)
case "restart":
return s.allocRestart(allocID, resp, req)
case "gc":
return s.allocGC(allocID, resp, req)
case "signal":
return s.allocSignal(allocID, resp, req)
}
return nil, CodedError(404, resourceNotFoundErr)
}
func (s *HTTPServer) ClientGCRequest(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
// Get the requested Node ID
requestedNode := req.URL.Query().Get("node_id")
// Build the request and parse the ACL token
args := structs.NodeSpecificRequest{
NodeID: requestedNode,
}
s.parse(resp, req, &args.QueryOptions.Region, &args.QueryOptions)
// Determine the handler to use
useLocalClient, useClientRPC, useServerRPC := s.rpcHandlerForNode(requestedNode)
// Make the RPC
var reply structs.GenericResponse
var rpcErr error
if useLocalClient {
rpcErr = s.agent.Client().ClientRPC("Allocations.GarbageCollectAll", &args, &reply)
} else if useClientRPC {
rpcErr = s.agent.Client().RPC("ClientAllocations.GarbageCollectAll", &args, &reply)
} else if useServerRPC {
rpcErr = s.agent.Server().RPC("ClientAllocations.GarbageCollectAll", &args, &reply)
} else {
rpcErr = CodedError(400, "No local Node and node_id not provided")
}
if rpcErr != nil {
if structs.IsErrNoNodeConn(rpcErr) {
rpcErr = CodedError(404, rpcErr.Error())
}
}
return nil, rpcErr
}
func (s *HTTPServer) allocRestart(allocID string, resp http.ResponseWriter, req *http.Request) (interface{}, error) {
// Build the request and parse the ACL token
args := structs.AllocRestartRequest{
AllocID: allocID,
TaskName: "",
}
s.parse(resp, req, &args.QueryOptions.Region, &args.QueryOptions)
// Explicitly parse the body separately to disallow overriding AllocID in req Body.
var reqBody struct {
TaskName string
}
err := json.NewDecoder(req.Body).Decode(&reqBody)
if err != nil && err != io.EOF {
return nil, err
}
if reqBody.TaskName != "" {
args.TaskName = reqBody.TaskName
}
// Determine the handler to use
useLocalClient, useClientRPC, useServerRPC := s.rpcHandlerForAlloc(allocID)
// Make the RPC
var reply structs.GenericResponse
var rpcErr error
if useLocalClient {
rpcErr = s.agent.Client().ClientRPC("Allocations.Restart", &args, &reply)
} else if useClientRPC {
rpcErr = s.agent.Client().RPC("ClientAllocations.Restart", &args, &reply)
} else if useServerRPC {
rpcErr = s.agent.Server().RPC("ClientAllocations.Restart", &args, &reply)
} else {
rpcErr = CodedError(400, "No local Node and node_id not provided")
}
if rpcErr != nil {
if structs.IsErrNoNodeConn(rpcErr) || structs.IsErrUnknownAllocation(rpcErr) {
rpcErr = CodedError(404, rpcErr.Error())
}
}
return reply, rpcErr
}
func (s *HTTPServer) allocGC(allocID string, resp http.ResponseWriter, req *http.Request) (interface{}, error) {
// Build the request and parse the ACL token
args := structs.AllocSpecificRequest{
AllocID: allocID,
}
s.parse(resp, req, &args.QueryOptions.Region, &args.QueryOptions)
// Determine the handler to use
useLocalClient, useClientRPC, useServerRPC := s.rpcHandlerForAlloc(allocID)
// Make the RPC
var reply structs.GenericResponse
var rpcErr error
if useLocalClient {
rpcErr = s.agent.Client().ClientRPC("Allocations.GarbageCollect", &args, &reply)
} else if useClientRPC {
rpcErr = s.agent.Client().RPC("ClientAllocations.GarbageCollect", &args, &reply)
} else if useServerRPC {
rpcErr = s.agent.Server().RPC("ClientAllocations.GarbageCollect", &args, &reply)
} else {
rpcErr = CodedError(400, "No local Node and node_id not provided")
}
if rpcErr != nil {
if structs.IsErrNoNodeConn(rpcErr) || structs.IsErrUnknownAllocation(rpcErr) {
rpcErr = CodedError(404, rpcErr.Error())
}
}
return nil, rpcErr
}
func (s *HTTPServer) allocSignal(allocID string, resp http.ResponseWriter, req *http.Request) (interface{}, error) {
if !(req.Method == "POST" || req.Method == "PUT") {
return nil, CodedError(405, ErrInvalidMethod)
}
// Build the request and parse the ACL token
args := structs.AllocSignalRequest{}
err := decodeBody(req, &args)
if err != nil {
return nil, CodedError(400, fmt.Sprintf("Failed to decode body: %v", err))
}
s.parse(resp, req, &args.QueryOptions.Region, &args.QueryOptions)
args.AllocID = allocID
// Determine the handler to use
useLocalClient, useClientRPC, useServerRPC := s.rpcHandlerForAlloc(allocID)
// Make the RPC
var reply structs.GenericResponse
var rpcErr error
if useLocalClient {
rpcErr = s.agent.Client().ClientRPC("Allocations.Signal", &args, &reply)
} else if useClientRPC {
rpcErr = s.agent.Client().RPC("ClientAllocations.Signal", &args, &reply)
} else if useServerRPC {
rpcErr = s.agent.Server().RPC("ClientAllocations.Signal", &args, &reply)
} else {
rpcErr = CodedError(400, "No local Node and node_id not provided")
}
if rpcErr != nil {
if structs.IsErrNoNodeConn(rpcErr) || structs.IsErrUnknownAllocation(rpcErr) {
rpcErr = CodedError(404, rpcErr.Error())
}
}
return reply, rpcErr
}
func (s *HTTPServer) allocSnapshot(allocID string, resp http.ResponseWriter, req *http.Request) (interface{}, error) {
var secret string
s.parseToken(req, &secret)
if !s.agent.Client().ValidateMigrateToken(allocID, secret) {
return nil, structs.ErrPermissionDenied
}
allocFS, err := s.agent.Client().GetAllocFS(allocID)
if err != nil {
return nil, fmt.Errorf(allocNotFoundErr)
}
if err := allocFS.Snapshot(resp); err != nil {
return nil, fmt.Errorf("error making snapshot: %v", err)
}
return nil, nil
}
func (s *HTTPServer) allocStats(allocID string, resp http.ResponseWriter, req *http.Request) (interface{}, error) {
// Build the request and parse the ACL token
task := req.URL.Query().Get("task")
args := cstructs.AllocStatsRequest{
AllocID: allocID,
Task: task,
}
s.parse(resp, req, &args.QueryOptions.Region, &args.QueryOptions)
// Determine the handler to use
useLocalClient, useClientRPC, useServerRPC := s.rpcHandlerForAlloc(allocID)
// Make the RPC
var reply cstructs.AllocStatsResponse
var rpcErr error
if useLocalClient {
rpcErr = s.agent.Client().ClientRPC("Allocations.Stats", &args, &reply)
} else if useClientRPC {
rpcErr = s.agent.Client().RPC("ClientAllocations.Stats", &args, &reply)
} else if useServerRPC {
rpcErr = s.agent.Server().RPC("ClientAllocations.Stats", &args, &reply)
} else {
rpcErr = CodedError(400, "No local Node and node_id not provided")
}
if rpcErr != nil {
if structs.IsErrNoNodeConn(rpcErr) || structs.IsErrUnknownAllocation(rpcErr) {
rpcErr = CodedError(404, rpcErr.Error())
}
}
return reply.Stats, rpcErr
}
func (s *HTTPServer) allocExec(allocID string, resp http.ResponseWriter, req *http.Request) (interface{}, error) {
// Build the request and parse the ACL token
task := req.URL.Query().Get("task")
cmdJsonStr := req.URL.Query().Get("command")
var command []string
err := json.Unmarshal([]byte(cmdJsonStr), &command)
if err != nil {
// this shouldn't happen, []string is always be serializable to json
return nil, fmt.Errorf("failed to marshal command into json: %v", err)
}
ttyB := false
if tty := req.URL.Query().Get("tty"); tty != "" {
ttyB, err = strconv.ParseBool(tty)
if err != nil {
return nil, fmt.Errorf("tty value is not a boolean: %v", err)
}
}
args := cstructs.AllocExecRequest{
AllocID: allocID,
Task: task,
Cmd: command,
Tty: ttyB,
}
s.parse(resp, req, &args.QueryOptions.Region, &args.QueryOptions)
conn, err := s.wsUpgrader.Upgrade(resp, req, nil)
if err != nil {
return nil, fmt.Errorf("failed to upgrade connection: %v", err)
}
return s.execStreamImpl(conn, &args)
}
func (s *HTTPServer) execStreamImpl(ws *websocket.Conn, args *cstructs.AllocExecRequest) (interface{}, error) {
allocID := args.AllocID
method := "Allocations.Exec"
// Get the correct handler
localClient, remoteClient, localServer := s.rpcHandlerForAlloc(allocID)
var handler structs.StreamingRpcHandler
var handlerErr error
if localClient {
handler, handlerErr = s.agent.Client().StreamingRpcHandler(method)
} else if remoteClient {
handler, handlerErr = s.agent.Client().RemoteStreamingRpcHandler(method)
} else if localServer {
handler, handlerErr = s.agent.Server().StreamingRpcHandler(method)
}
if handlerErr != nil {
return nil, CodedError(500, handlerErr.Error())
}
// Create a pipe connecting the (possibly remote) handler to the http response
httpPipe, handlerPipe := net.Pipe()
decoder := codec.NewDecoder(httpPipe, structs.MsgpackHandle)
encoder := codec.NewEncoder(httpPipe, structs.MsgpackHandle)
// Create a goroutine that closes the pipe if the connection closes.
ctx, cancel := context.WithCancel(context.Background())
go func() {
<-ctx.Done()
httpPipe.Close()
// don't close ws - wait to drain messages
}()
// Create a channel that decodes the results
errCh := make(chan HTTPCodedError, 2)
// stream response
go func() {
defer cancel()
// Send the request
if err := encoder.Encode(args); err != nil {
errCh <- CodedError(500, err.Error())
return
}
go forwardExecInput(encoder, ws, errCh)
for {
select {
case <-ctx.Done():
errCh <- nil
return
default:
}
var res cstructs.StreamErrWrapper
err := decoder.Decode(&res)
if isClosedError(err) {
ws.WriteMessage(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseNormalClosure, ""))
errCh <- nil
return
}
if err != nil {
errCh <- CodedError(500, err.Error())
return
}
decoder.Reset(httpPipe)
if err := res.Error; err != nil {
code := 500
if err.Code != nil {
code = int(*err.Code)
}
errCh <- CodedError(code, err.Error())
return
}
if err := ws.WriteMessage(websocket.TextMessage, res.Payload); err != nil {
errCh <- CodedError(500, err.Error())
return
}
}
}()
// start streaming request to streaming RPC - returns when streaming completes or errors
handler(handlerPipe)
// stop streaming background goroutines for streaming - but not websocket activity
cancel()
// retreieve any error and/or wait until goroutine stop and close errCh connection before
// closing websocket connection
codedErr := <-errCh
if isClosedError(codedErr) {
codedErr = nil
} else if codedErr != nil {
ws.WriteMessage(websocket.CloseMessage,
websocket.FormatCloseMessage(toWsCode(codedErr.Code()), codedErr.Error()))
}
ws.Close()
return nil, codedErr
}
func toWsCode(httpCode int) int {
switch httpCode {
case 500:
return websocket.CloseInternalServerErr
default:
// placeholder error code
return websocket.ClosePolicyViolation
}
}
func isClosedError(err error) bool {
if err == nil {
return false
}
return err == io.EOF ||
err == io.ErrClosedPipe ||
strings.Contains(err.Error(), "closed") ||
strings.Contains(err.Error(), "EOF")
}
// forwardExecInput forwards exec input (e.g. stdin) from websocket connection
// to the streaming RPC connection to client
func forwardExecInput(encoder *codec.Encoder, ws *websocket.Conn, errCh chan<- HTTPCodedError) {
for {
sf := &drivers.ExecTaskStreamingRequestMsg{}
err := ws.ReadJSON(sf)
if err == io.EOF {
return
}
if err != nil {
errCh <- CodedError(500, err.Error())
return
}
err = encoder.Encode(sf)
if err != nil {
errCh <- CodedError(500, err.Error())
}
}
}