aboutsummaryrefslogtreecommitdiff
path: root/pkg/domain/infra/abi/containers_runlabel.go
blob: d448627dcd045204c38120df64bcfbcb1e6d3e03 (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
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
package abi

import (
	"context"
	"fmt"
	"os"
	"path/filepath"
	"strings"

	"github.com/containers/common/libimage"
	"github.com/containers/common/pkg/config"
	"github.com/containers/podman/v3/libpod/define"
	"github.com/containers/podman/v3/pkg/domain/entities"
	envLib "github.com/containers/podman/v3/pkg/env"
	"github.com/containers/podman/v3/utils"
	"github.com/google/shlex"
	"github.com/pkg/errors"
	"github.com/sirupsen/logrus"
)

func (ic *ContainerEngine) ContainerRunlabel(ctx context.Context, label string, imageRef string, args []string, options entities.ContainerRunlabelOptions) error {
	pullOptions := &libimage.PullOptions{}
	pullOptions.AuthFilePath = options.Authfile
	pullOptions.CertDirPath = options.CertDir
	pullOptions.Credentials = options.Credentials
	pullOptions.SignaturePolicyPath = options.SignaturePolicy
	pullOptions.InsecureSkipTLSVerify = options.SkipTLSVerify

	pullPolicy := config.PullPolicyNever
	if options.Pull {
		pullPolicy = config.PullPolicyMissing
	}
	if !options.Quiet {
		pullOptions.Writer = os.Stderr
	}

	pulledImages, err := ic.Libpod.LibimageRuntime().Pull(ctx, imageRef, pullPolicy, pullOptions)
	if err != nil {
		return err
	}

	if len(pulledImages) != 1 {
		return errors.Errorf("internal error: expected an image to be pulled (or an error)")
	}

	// Extract the runlabel from the image.
	labels, err := pulledImages[0].Labels(ctx)
	if err != nil {
		return err
	}

	var runlabel string
	for k, v := range labels {
		if strings.EqualFold(k, label) {
			runlabel = v
			break
		}
	}
	if runlabel == "" {
		return errors.Errorf("cannot find the value of label: %s in image: %s", label, imageRef)
	}

	cmd, env, err := generateRunlabelCommand(runlabel, pulledImages[0], imageRef, args, options)
	if err != nil {
		return err
	}

	if options.Display {
		fmt.Printf("command: %s\n", strings.Join(append([]string{os.Args[0]}, cmd[1:]...), " "))
		return nil
	}

	stdErr := os.Stderr
	stdOut := os.Stdout
	stdIn := os.Stdin
	if options.Quiet {
		stdErr = nil
		stdOut = nil
		stdIn = nil
	}

	// If container already exists && --replace given -- Nuke it
	if options.Replace {
		for i, entry := range cmd {
			if entry == "--name" {
				name := cmd[i+1]
				ctr, err := ic.Libpod.LookupContainer(name)
				if err != nil {
					if errors.Cause(err) != define.ErrNoSuchCtr {
						logrus.Debugf("Error occurred searching for container %s: %s", name, err.Error())
						return err
					}
				} else {
					logrus.Debugf("Runlabel --replace option given. Container %s will be deleted. The new container will be named %s", ctr.ID(), name)
					if err := ic.Libpod.RemoveContainer(ctx, ctr, true, false); err != nil {
						return err
					}
				}
				break
			}
		}
	}

	return utils.ExecCmdWithStdStreams(stdIn, stdOut, stdErr, env, cmd[0], cmd[1:]...)
}

// generateRunlabelCommand generates the to-be-executed command as a string
// slice along with a base environment.
func generateRunlabelCommand(runlabel string, img *libimage.Image, inputName string, args []string, options entities.ContainerRunlabelOptions) ([]string, []string, error) {
	var (
		err             error
		name, imageName string
		globalOpts      string
		cmd             []string
	)

	// Extract the imageName (or ID).
	imgNames := img.NamesHistory()
	if len(imgNames) == 0 {
		imageName = img.ID()
	} else {
		// The newest name is the first entry in the `NamesHistory`
		// slice.
		imageName = imgNames[0]
	}

	// Use the user-specified name or extract one from the image.
	name = options.Name
	if name == "" {
		normalize := imageName
		if !strings.HasPrefix(img.ID(), inputName) {
			normalize = inputName
		}
		splitImageName := strings.Split(normalize, "/")
		name = splitImageName[len(splitImageName)-1]
	}

	// Append the user-specified arguments to the runlabel (command).
	if len(args) > 0 {
		runlabel = fmt.Sprintf("%s %s", runlabel, strings.Join(args, " "))
	}

	cmd, err = generateCommand(runlabel, imageName, name, globalOpts)
	if err != nil {
		return nil, nil, err
	}

	env := generateRunEnvironment(options)
	env = append(env, "PODMAN_RUNLABEL_NESTED=1")
	envmap, err := envLib.ParseSlice(env)
	if err != nil {
		return nil, nil, err
	}

	envmapper := func(k string) string {
		switch k {
		case "OPT1":
			return envmap["OPT1"]
		case "OPT2":
			return envmap["OPT2"]
		case "OPT3":
			return envmap["OPT3"]
		case "PWD":
			// I would prefer to use os.getenv but it appears PWD is not in the os env list.
			d, err := os.Getwd()
			if err != nil {
				logrus.Error("unable to determine current working directory")
				return ""
			}
			return d
		}
		return ""
	}
	newS := os.Expand(strings.Join(cmd, " "), envmapper)
	cmd, err = shlex.Split(newS)
	if err != nil {
		return nil, nil, err
	}
	return cmd, env, nil
}

func replaceName(arg, name string) string {
	if arg == "NAME" {
		return name
	}

	newarg := strings.ReplaceAll(arg, "$NAME", name)
	newarg = strings.ReplaceAll(newarg, "${NAME}", name)
	if strings.HasSuffix(newarg, "=NAME") {
		newarg = strings.ReplaceAll(newarg, "=NAME", fmt.Sprintf("=%s", name))
	}
	return newarg
}

func replaceImage(arg, image string) string {
	if arg == "IMAGE" {
		return image
	}
	newarg := strings.ReplaceAll(arg, "$IMAGE", image)
	newarg = strings.ReplaceAll(newarg, "${IMAGE}", image)
	if strings.HasSuffix(newarg, "=IMAGE") {
		newarg = strings.ReplaceAll(newarg, "=IMAGE", fmt.Sprintf("=%s", image))
	}
	return newarg
}

// generateCommand takes a label (string) and converts it to an executable command
func generateCommand(command, imageName, name, globalOpts string) ([]string, error) {
	if name == "" {
		name = imageName
	}

	cmd, err := shlex.Split(command)
	if err != nil {
		return nil, err
	}

	prog, err := substituteCommand(cmd[0])
	if err != nil {
		return nil, err
	}
	newCommand := []string{prog}
	for _, arg := range cmd[1:] {
		var newArg string
		switch arg {
		case "IMAGE=IMAGE":
			newArg = fmt.Sprintf("IMAGE=%s", imageName)
		case "NAME=NAME":
			newArg = fmt.Sprintf("NAME=%s", name)
		case "$GLOBAL_OPTS":
			newArg = globalOpts
		default:
			newArg = replaceName(arg, name)
			newArg = replaceImage(newArg, imageName)
		}
		newCommand = append(newCommand, newArg)
	}
	return newCommand, nil
}

// GenerateRunEnvironment merges the current environment variables with optional
// environment variables provided by the user
func generateRunEnvironment(options entities.ContainerRunlabelOptions) []string {
	newEnv := os.Environ()
	if options.Optional1 != "" {
		newEnv = append(newEnv, fmt.Sprintf("OPT1=%s", options.Optional1))
	}
	if options.Optional2 != "" {
		newEnv = append(newEnv, fmt.Sprintf("OPT2=%s", options.Optional2))
	}
	if options.Optional3 != "" {
		newEnv = append(newEnv, fmt.Sprintf("OPT3=%s", options.Optional3))
	}
	return newEnv
}

func substituteCommand(cmd string) (string, error) {
	var (
		newCommand string
	)

	// Replace cmd with "/proc/self/exe" if "podman" or "docker" is being
	// used. If "/usr/bin/docker" is provided, we also sub in podman.
	// Otherwise, leave the command unchanged.
	if cmd == "podman" || filepath.Base(cmd) == "docker" {
		newCommand = "/proc/self/exe"
	} else {
		newCommand = cmd
	}

	// If cmd is an absolute or relative path, check if the file exists.
	// Throw an error if it doesn't exist.
	if strings.Contains(newCommand, "/") || strings.HasPrefix(newCommand, ".") {
		res, err := filepath.Abs(newCommand)
		if err != nil {
			return "", err
		}
		if _, err := os.Stat(res); !os.IsNotExist(err) {
			return res, nil
		} else if err != nil {
			return "", err
		}
	}

	return newCommand, nil
}