summaryrefslogtreecommitdiff
path: root/pkg/api/handlers/compat/containers_attach.go
blob: aad6e22940410aba78abd3ba2036a0584c35c349 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
package compat

import (
	"fmt"
	"net/http"

	"github.com/containers/libpod/libpod"
	"github.com/containers/libpod/libpod/define"
	"github.com/containers/libpod/pkg/api/handlers/utils"
	"github.com/gorilla/schema"
	"github.com/pkg/errors"
	"github.com/sirupsen/logrus"
)

// AttachHeader is the literal header sent for upgraded/hijacked connections for
// attach, sourced from Docker at:
// https://raw.githubusercontent.com/moby/moby/b95fad8e51bd064be4f4e58a996924f343846c85/api/server/router/container/container_routes.go
// Using literally to ensure compatibility with existing clients.
const AttachHeader = "HTTP/1.1 101 UPGRADED\r\nContent-Type: application/vnd.docker.raw-stream\r\nConnection: Upgrade\r\nUpgrade: tcp\r\n\r\n"

func AttachContainer(w http.ResponseWriter, r *http.Request) {
	runtime := r.Context().Value("runtime").(*libpod.Runtime)
	decoder := r.Context().Value("decoder").(*schema.Decoder)

	query := struct {
		DetachKeys string `schema:"detachKeys"`
		Logs       bool   `schema:"logs"`
		Stream     bool   `schema:"stream"`
		Stdin      bool   `schema:"stdin"`
		Stdout     bool   `schema:"stdout"`
		Stderr     bool   `schema:"stderr"`
	}{
		Stream: true,
	}
	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
		utils.Error(w, "Error parsing parameters", http.StatusBadRequest, err)
		return
	}

	// Detach keys: explicitly set to "" is very different from unset
	// TODO: Our format for parsing these may be different from Docker.
	var detachKeys *string
	if _, found := r.URL.Query()["detachKeys"]; found {
		detachKeys = &query.DetachKeys
	}

	streams := new(libpod.HTTPAttachStreams)
	streams.Stdout = true
	streams.Stderr = true
	streams.Stdin = true
	useStreams := false
	if _, found := r.URL.Query()["stdin"]; found {
		streams.Stdin = query.Stdin
		useStreams = true
	}
	if _, found := r.URL.Query()["stdout"]; found {
		streams.Stdout = query.Stdout
		useStreams = true
	}
	if _, found := r.URL.Query()["stderr"]; found {
		streams.Stderr = query.Stderr
		useStreams = true
	}
	if !useStreams {
		streams = nil
	}
	if useStreams && !streams.Stdout && !streams.Stderr && !streams.Stdin {
		utils.Error(w, "Parameter conflict", http.StatusBadRequest, errors.Errorf("at least one of stdin, stdout, stderr must be true"))
		return
	}

	// At least one of these must be set
	if !query.Stream && !query.Logs {
		utils.Error(w, "Unsupported parameter", http.StatusBadRequest, errors.Errorf("at least one of Logs or Stream must be set"))
		return
	}

	name := utils.GetName(r)
	ctr, err := runtime.LookupContainer(name)
	if err != nil {
		utils.ContainerNotFound(w, name, err)
		return
	}

	state, err := ctr.State()
	if err != nil {
		utils.InternalServerError(w, err)
		return
	}
	// For Docker compatibility, we need to re-initialize containers in these states.
	if state == define.ContainerStateConfigured || state == define.ContainerStateExited {
		if err := ctr.Init(r.Context(), ctr.PodID() != ""); err != nil {
			utils.Error(w, "Container in wrong state", http.StatusConflict, errors.Wrapf(err, "error preparing container %s for attach", ctr.ID()))
			return
		}
	} else if !(state == define.ContainerStateCreated || state == define.ContainerStateRunning) {
		utils.InternalServerError(w, errors.Wrapf(define.ErrCtrStateInvalid, "can only attach to created or running containers - currently in state %s", state.String()))
		return
	}

	// Hijack the connection
	hijacker, ok := w.(http.Hijacker)
	if !ok {
		utils.InternalServerError(w, errors.Errorf("unable to hijack connection"))
		return
	}

	connection, buffer, err := hijacker.Hijack()
	if err != nil {
		utils.InternalServerError(w, errors.Wrapf(err, "error hijacking connection"))
		return
	}

	fmt.Fprintf(connection, AttachHeader)

	logrus.Debugf("Hijack for attach of container %s successful", ctr.ID())

	// Perform HTTP attach.
	// HTTPAttach will handle everything about the connection from here on
	// (including closing it and writing errors to it).
	if err := ctr.HTTPAttach(connection, buffer, streams, detachKeys, nil, query.Stream, query.Logs); err != nil {
		// We can't really do anything about errors anymore. HTTPAttach
		// should be writing them to the connection.
		logrus.Errorf("Error attaching to container %s: %v", ctr.ID(), err)
	}

	logrus.Debugf("Attach for container %s completed successfully", ctr.ID())
}