open-nomad/nomad/client_fs_endpoint.go

445 lines
12 KiB
Go

package nomad
import (
"errors"
"fmt"
"io"
"net"
"strings"
"time"
metrics "github.com/armon/go-metrics"
log "github.com/hashicorp/go-hclog"
cstructs "github.com/hashicorp/nomad/client/structs"
"github.com/hashicorp/go-msgpack/codec"
"github.com/hashicorp/nomad/acl"
"github.com/hashicorp/nomad/helper"
"github.com/hashicorp/nomad/nomad/structs"
)
// FileSystem endpoint is used for accessing the logs and filesystem of
// allocations from a Node.
type FileSystem struct {
srv *Server
logger log.Logger
}
func (f *FileSystem) register() {
f.srv.streamingRpcs.Register("FileSystem.Logs", f.logs)
f.srv.streamingRpcs.Register("FileSystem.Stream", f.stream)
}
// handleStreamResultError is a helper for sending an error with a potential
// error code. The transmission of the error is ignored if the error has been
// generated by the closing of the underlying transport.
func handleStreamResultError(err error, code *int64, encoder *codec.Encoder) {
// Nothing to do as the conn is closed
if err == io.EOF || strings.Contains(err.Error(), "closed") {
return
}
// Attempt to send the error
encoder.Encode(&cstructs.StreamErrWrapper{
Error: cstructs.NewRpcError(err, code),
})
}
// forwardRegionStreamingRpc is used to make a streaming RPC to a different
// region. It looks up the allocation in the remote region to determine what
// remote server can route the request.
func forwardRegionStreamingRpc(fsrv *Server, conn io.ReadWriteCloser,
encoder *codec.Encoder, args interface{}, method, allocID string, qo *structs.QueryOptions) {
// Request the allocation from the target region
allocReq := &structs.AllocSpecificRequest{
AllocID: allocID,
QueryOptions: *qo,
}
var allocResp structs.SingleAllocResponse
if err := fsrv.forwardRegion(qo.RequestRegion(), "Alloc.GetAlloc", allocReq, &allocResp); err != nil {
handleStreamResultError(err, nil, encoder)
return
}
if allocResp.Alloc == nil {
handleStreamResultError(structs.NewErrUnknownAllocation(allocID), helper.Int64ToPtr(404), encoder)
return
}
// Determine the Server that has a connection to the node.
srv, err := fsrv.serverWithNodeConn(allocResp.Alloc.NodeID, qo.RequestRegion())
if err != nil {
var code *int64
if structs.IsErrNoNodeConn(err) {
code = helper.Int64ToPtr(404)
}
handleStreamResultError(err, code, encoder)
return
}
// Get a connection to the server
srvConn, err := fsrv.streamingRpc(srv, method)
if err != nil {
handleStreamResultError(err, nil, encoder)
return
}
defer srvConn.Close()
// Send the request.
outEncoder := codec.NewEncoder(srvConn, structs.MsgpackHandle)
if err := outEncoder.Encode(args); err != nil {
handleStreamResultError(err, nil, encoder)
return
}
structs.Bridge(conn, srvConn)
}
// List is used to list the contents of an allocation's directory.
func (f *FileSystem) List(args *cstructs.FsListRequest, reply *cstructs.FsListResponse) error {
// We only allow stale reads since the only potentially stale information is
// the Node registration and the cost is fairly high for adding another hope
// in the forwarding chain.
args.QueryOptions.AllowStale = true
// Potentially forward to a different region.
if done, err := f.srv.forward("FileSystem.List", args, args, reply); done {
return err
}
defer metrics.MeasureSince([]string{"nomad", "file_system", "list"}, time.Now())
// Verify the arguments.
if args.AllocID == "" {
return errors.New("missing allocation ID")
}
// Lookup the allocation
snap, err := f.srv.State().Snapshot()
if err != nil {
return err
}
alloc, err := getAlloc(snap, args.AllocID)
if err != nil {
return err
}
// Check namespace filesystem read permissions
allowNsOp := acl.NamespaceValidator(acl.NamespaceCapabilityReadFS)
aclObj, err := f.srv.ResolveToken(args.AuthToken)
if err != nil {
return err
} else if !allowNsOp(aclObj, alloc.Namespace) {
return structs.ErrPermissionDenied
}
// Make sure Node is valid and new enough to support RPC
_, err = getNodeForRpc(snap, alloc.NodeID)
if err != nil {
return err
}
// Get the connection to the client
state, ok := f.srv.getNodeConn(alloc.NodeID)
if !ok {
return findNodeConnAndForward(f.srv, alloc.NodeID, "FileSystem.List", args, reply)
}
// Make the RPC
return NodeRpc(state.Session, "FileSystem.List", args, reply)
}
// Stat is used to stat a file in the allocation's directory.
func (f *FileSystem) Stat(args *cstructs.FsStatRequest, reply *cstructs.FsStatResponse) error {
// We only allow stale reads since the only potentially stale information is
// the Node registration and the cost is fairly high for adding another hope
// in the forwarding chain.
args.QueryOptions.AllowStale = true
// Potentially forward to a different region.
if done, err := f.srv.forward("FileSystem.Stat", args, args, reply); done {
return err
}
defer metrics.MeasureSince([]string{"nomad", "file_system", "stat"}, time.Now())
// Verify the arguments.
if args.AllocID == "" {
return errors.New("missing allocation ID")
}
// Lookup the allocation
snap, err := f.srv.State().Snapshot()
if err != nil {
return err
}
alloc, err := getAlloc(snap, args.AllocID)
if err != nil {
return err
}
// Check filesystem read permissions
if aclObj, err := f.srv.ResolveToken(args.AuthToken); err != nil {
return err
} else if aclObj != nil && !aclObj.AllowNsOp(alloc.Namespace, acl.NamespaceCapabilityReadFS) {
return structs.ErrPermissionDenied
}
// Make sure Node is valid and new enough to support RPC
_, err = getNodeForRpc(snap, alloc.NodeID)
if err != nil {
return err
}
// Get the connection to the client
state, ok := f.srv.getNodeConn(alloc.NodeID)
if !ok {
return findNodeConnAndForward(f.srv, alloc.NodeID, "FileSystem.Stat", args, reply)
}
// Make the RPC
return NodeRpc(state.Session, "FileSystem.Stat", args, reply)
}
// stream is is used to stream the contents of file in an allocation's
// directory.
func (f *FileSystem) stream(conn io.ReadWriteCloser) {
defer conn.Close()
defer metrics.MeasureSince([]string{"nomad", "file_system", "stream"}, time.Now())
// Decode the arguments
var args cstructs.FsStreamRequest
decoder := codec.NewDecoder(conn, structs.MsgpackHandle)
encoder := codec.NewEncoder(conn, structs.MsgpackHandle)
if err := decoder.Decode(&args); err != nil {
handleStreamResultError(err, helper.Int64ToPtr(500), encoder)
return
}
// Check if we need to forward to a different region
if r := args.RequestRegion(); r != f.srv.Region() {
forwardRegionStreamingRpc(f.srv, conn, encoder, &args, "FileSystem.Stream",
args.AllocID, &args.QueryOptions)
return
}
// Verify the arguments.
if args.AllocID == "" {
handleStreamResultError(errors.New("missing AllocID"), helper.Int64ToPtr(400), encoder)
return
}
// Retrieve the allocation
snap, err := f.srv.State().Snapshot()
if err != nil {
handleStreamResultError(err, nil, encoder)
return
}
alloc, err := getAlloc(snap, args.AllocID)
if structs.IsErrUnknownAllocation(err) {
handleStreamResultError(structs.NewErrUnknownAllocation(args.AllocID), helper.Int64ToPtr(404), encoder)
return
}
if err != nil {
handleStreamResultError(err, nil, encoder)
return
}
// Check namespace read-fs permissions.
if aclObj, err := f.srv.ResolveToken(args.AuthToken); err != nil {
handleStreamResultError(err, nil, encoder)
return
} else if aclObj != nil && !aclObj.AllowNsOp(alloc.Namespace, acl.NamespaceCapabilityReadFS) {
handleStreamResultError(structs.ErrPermissionDenied, nil, encoder)
return
}
nodeID := alloc.NodeID
// Make sure Node is valid and new enough to support RPC
node, err := snap.NodeByID(nil, nodeID)
if err != nil {
handleStreamResultError(err, helper.Int64ToPtr(500), encoder)
return
}
if node == nil {
err := fmt.Errorf("Unknown node %q", nodeID)
handleStreamResultError(err, helper.Int64ToPtr(400), encoder)
return
}
if err := nodeSupportsRpc(node); err != nil {
handleStreamResultError(err, helper.Int64ToPtr(400), encoder)
return
}
// Get the connection to the client either by forwarding to another server
// or creating a direct stream
var clientConn net.Conn
state, ok := f.srv.getNodeConn(nodeID)
if !ok {
// Determine the Server that has a connection to the node.
srv, err := f.srv.serverWithNodeConn(nodeID, f.srv.Region())
if err != nil {
var code *int64
if structs.IsErrNoNodeConn(err) {
code = helper.Int64ToPtr(404)
}
handleStreamResultError(err, code, encoder)
return
}
// Get a connection to the server
conn, err := f.srv.streamingRpc(srv, "FileSystem.Stream")
if err != nil {
handleStreamResultError(err, nil, encoder)
return
}
clientConn = conn
} else {
stream, err := NodeStreamingRpc(state.Session, "FileSystem.Stream")
if err != nil {
handleStreamResultError(err, nil, encoder)
return
}
clientConn = stream
}
defer clientConn.Close()
// Send the request.
outEncoder := codec.NewEncoder(clientConn, structs.MsgpackHandle)
if err := outEncoder.Encode(args); err != nil {
handleStreamResultError(err, nil, encoder)
return
}
structs.Bridge(conn, clientConn)
return
}
// logs is used to access an task's logs for a given allocation
func (f *FileSystem) logs(conn io.ReadWriteCloser) {
defer conn.Close()
defer metrics.MeasureSince([]string{"nomad", "file_system", "logs"}, time.Now())
// Decode the arguments
var args cstructs.FsLogsRequest
decoder := codec.NewDecoder(conn, structs.MsgpackHandle)
encoder := codec.NewEncoder(conn, structs.MsgpackHandle)
if err := decoder.Decode(&args); err != nil {
handleStreamResultError(err, helper.Int64ToPtr(500), encoder)
return
}
// Check if we need to forward to a different region
if r := args.RequestRegion(); r != f.srv.Region() {
forwardRegionStreamingRpc(f.srv, conn, encoder, &args, "FileSystem.Logs",
args.AllocID, &args.QueryOptions)
return
}
// Verify the arguments.
if args.AllocID == "" {
handleStreamResultError(structs.ErrMissingAllocID, helper.Int64ToPtr(400), encoder)
return
}
// Retrieve the allocation
snap, err := f.srv.State().Snapshot()
if err != nil {
handleStreamResultError(err, nil, encoder)
return
}
alloc, err := getAlloc(snap, args.AllocID)
if structs.IsErrUnknownAllocation(err) {
handleStreamResultError(structs.NewErrUnknownAllocation(args.AllocID), helper.Int64ToPtr(404), encoder)
return
}
if err != nil {
handleStreamResultError(err, nil, encoder)
return
}
// Check namespace read-logs *or* read-fs permissions.
allowNsOp := acl.NamespaceValidator(
acl.NamespaceCapabilityReadFS, acl.NamespaceCapabilityReadLogs)
aclObj, err := f.srv.ResolveToken(args.AuthToken)
if err != nil {
handleStreamResultError(err, nil, encoder)
return
} else if !allowNsOp(aclObj, alloc.Namespace) {
handleStreamResultError(structs.ErrPermissionDenied, nil, encoder)
return
}
nodeID := alloc.NodeID
// Make sure Node is valid and new enough to support RPC
node, err := snap.NodeByID(nil, nodeID)
if err != nil {
handleStreamResultError(err, helper.Int64ToPtr(500), encoder)
return
}
if node == nil {
err := fmt.Errorf("Unknown node %q", nodeID)
handleStreamResultError(err, helper.Int64ToPtr(400), encoder)
return
}
if err := nodeSupportsRpc(node); err != nil {
handleStreamResultError(err, helper.Int64ToPtr(400), encoder)
return
}
// Get the connection to the client either by forwarding to another server
// or creating a direct stream
var clientConn net.Conn
state, ok := f.srv.getNodeConn(nodeID)
if !ok {
// Determine the Server that has a connection to the node.
srv, err := f.srv.serverWithNodeConn(nodeID, f.srv.Region())
if err != nil {
var code *int64
if structs.IsErrNoNodeConn(err) {
code = helper.Int64ToPtr(404)
}
handleStreamResultError(err, code, encoder)
return
}
// Get a connection to the server
conn, err := f.srv.streamingRpc(srv, "FileSystem.Logs")
if err != nil {
handleStreamResultError(err, nil, encoder)
return
}
clientConn = conn
} else {
stream, err := NodeStreamingRpc(state.Session, "FileSystem.Logs")
if err != nil {
handleStreamResultError(err, nil, encoder)
return
}
clientConn = stream
}
defer clientConn.Close()
// Send the request.
outEncoder := codec.NewEncoder(clientConn, structs.MsgpackHandle)
if err := outEncoder.Encode(args); err != nil {
handleStreamResultError(err, nil, encoder)
return
}
structs.Bridge(conn, clientConn)
return
}