aboutsummaryrefslogtreecommitdiff
path: root/pkg/api/handlers/utils/containers.go
blob: 6c708f74eaec67dc9b6ed43e0ab81ab3bb4da643 (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
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
package utils

import (
	"context"
	"fmt"
	"net/http"
	"strconv"
	"time"

	"github.com/containers/podman/v3/libpod/events"
	"github.com/containers/podman/v3/pkg/domain/entities"
	"github.com/containers/podman/v3/pkg/domain/infra/abi"

	"github.com/containers/podman/v3/pkg/api/handlers"
	"github.com/sirupsen/logrus"

	"github.com/containers/podman/v3/libpod/define"

	"github.com/containers/podman/v3/libpod"
	"github.com/gorilla/schema"
	"github.com/pkg/errors"
)

type waitQueryDocker struct {
	Condition string `schema:"condition"`
}

type waitQueryLibpod struct {
	Interval  string                   `schema:"interval"`
	Condition []define.ContainerStatus `schema:"condition"`
}

func WaitContainerDocker(w http.ResponseWriter, r *http.Request) {
	var err error
	ctx := r.Context()

	query := waitQueryDocker{}

	decoder := ctx.Value("decoder").(*schema.Decoder)
	if err = decoder.Decode(&query, r.URL.Query()); err != nil {
		Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
		return
	}

	interval := time.Nanosecond

	condition := "not-running"
	if _, found := r.URL.Query()["condition"]; found {
		condition = query.Condition
		if !isValidDockerCondition(query.Condition) {
			BadRequest(w, "condition", condition, errors.New("not a valid docker condition"))
			return
		}
	}

	name := GetName(r)

	exists, err := containerExists(ctx, name)

	if err != nil {
		InternalServerError(w, err)
		return
	}
	if !exists {
		ContainerNotFound(w, name, define.ErrNoSuchCtr)
		return
	}

	// In docker compatibility mode we have to send headers in advance,
	// otherwise docker client would freeze.
	w.Header().Add("Content-Type", "application/json")
	w.WriteHeader(200)
	if flusher, ok := w.(http.Flusher); ok {
		flusher.Flush()
	}

	exitCode, err := waitDockerCondition(ctx, name, interval, condition)
	msg := ""
	if err != nil {
		logrus.Errorf("error while waiting on condition: %q", err)
		msg = err.Error()
	}
	responseData := handlers.ContainerWaitOKBody{
		StatusCode: int(exitCode),
		Error: struct {
			Message string
		}{
			Message: msg,
		},
	}
	enc := json.NewEncoder(w)
	enc.SetEscapeHTML(true)
	err = enc.Encode(&responseData)
	if err != nil {
		logrus.Errorf("unable to write json: %q", err)
	}
}

func WaitContainerLibpod(w http.ResponseWriter, r *http.Request) {
	var (
		err        error
		interval   = time.Millisecond * 250
		conditions = []define.ContainerStatus{define.ContainerStateStopped, define.ContainerStateExited}
	)
	decoder := r.Context().Value("decoder").(*schema.Decoder)
	query := waitQueryLibpod{}
	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
		Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
		return
	}

	if _, found := r.URL.Query()["interval"]; found {
		interval, err = time.ParseDuration(query.Interval)
		if err != nil {
			InternalServerError(w, err)
			return
		}
	}

	if _, found := r.URL.Query()["condition"]; found {
		if len(query.Condition) > 0 {
			conditions = query.Condition
		}
	}

	name := GetName(r)

	waitFn := createContainerWaitFn(r.Context(), name, interval)

	exitCode, err := waitFn(conditions...)
	if err != nil {
		if errors.Cause(err) == define.ErrNoSuchCtr {
			ContainerNotFound(w, name, err)
			return
		}
		InternalServerError(w, err)
		return
	}
	WriteResponse(w, http.StatusOK, strconv.Itoa(int(exitCode)))
}

type containerWaitFn func(conditions ...define.ContainerStatus) (int32, error)

func createContainerWaitFn(ctx context.Context, containerName string, interval time.Duration) containerWaitFn {
	runtime := ctx.Value("runtime").(*libpod.Runtime)
	var containerEngine entities.ContainerEngine = &abi.ContainerEngine{Libpod: runtime}

	return func(conditions ...define.ContainerStatus) (int32, error) {
		opts := entities.WaitOptions{
			Condition: conditions,
			Interval:  interval,
		}
		ctrWaitReport, err := containerEngine.ContainerWait(ctx, []string{containerName}, opts)
		if err != nil {
			return -1, err
		}
		if len(ctrWaitReport) != 1 {
			return -1, fmt.Errorf("the ContainerWait() function returned unexpected count of reports: %d", len(ctrWaitReport))
		}
		return ctrWaitReport[0].ExitCode, ctrWaitReport[0].Error
	}
}

func isValidDockerCondition(cond string) bool {
	switch cond {
	case "next-exit", "removed", "not-running", "":
		return true
	}
	return false
}

func waitDockerCondition(ctx context.Context, containerName string, interval time.Duration, dockerCondition string) (int32, error) {
	containerWait := createContainerWaitFn(ctx, containerName, interval)

	var err error
	var code int32
	switch dockerCondition {
	case "next-exit":
		code, err = waitNextExit(ctx, containerName)
	case "removed":
		code, err = waitRemoved(containerWait)
	case "not-running", "":
		code, err = waitNotRunning(containerWait)
	default:
		panic("not a valid docker condition")
	}
	return code, err
}

var notRunningStates = []define.ContainerStatus{
	define.ContainerStateCreated,
	define.ContainerStateRemoving,
	define.ContainerStateStopped,
	define.ContainerStateExited,
	define.ContainerStateConfigured,
}

func waitRemoved(ctrWait containerWaitFn) (int32, error) {
	code, err := ctrWait(define.ContainerStateUnknown)
	if err != nil && errors.Cause(err) == define.ErrNoSuchCtr {
		return code, nil
	}
	return code, err
}

func waitNextExit(ctx context.Context, containerName string) (int32, error) {
	runtime := ctx.Value("runtime").(*libpod.Runtime)
	containerEngine := &abi.ContainerEngine{Libpod: runtime}
	eventChannel := make(chan *events.Event)
	errChannel := make(chan error)
	opts := entities.EventsOptions{
		EventChan: eventChannel,
		Filter:    []string{"event=died", fmt.Sprintf("container=%s", containerName)},
		Stream:    true,
	}

	// ctx is used to cancel event watching goroutine
	ctx, cancel := context.WithCancel(ctx)
	defer cancel()
	go func() {
		errChannel <- containerEngine.Events(ctx, opts)
	}()

	evt, ok := <-eventChannel
	if ok {
		return int32(evt.ContainerExitCode), nil
	}
	// if ok == false then containerEngine.Events() has exited
	// it may happen if request was canceled (e.g. client closed connection prematurely) or
	// the server is in process of shutting down
	return -1, <-errChannel
}

func waitNotRunning(ctrWait containerWaitFn) (int32, error) {
	return ctrWait(notRunningStates...)
}

func containerExists(ctx context.Context, name string) (bool, error) {
	runtime := ctx.Value("runtime").(*libpod.Runtime)
	var containerEngine entities.ContainerEngine = &abi.ContainerEngine{Libpod: runtime}

	var ctrExistsOpts entities.ContainerExistsOptions
	ctrExistRep, err := containerEngine.ContainerExists(ctx, name, ctrExistsOpts)
	if err != nil {
		return false, err
	}
	return ctrExistRep.Value, nil
}