package main import ( "os" "path/filepath" "testing" "gotest.tools/v3/assert" ) // Try all of the test cases from the archive package which implements the // internals of `docker cp` and ensure that the behavior matches when actually // copying to and from containers. // Basic assumptions about SRC and DST: // 1. SRC must exist. // 2. If SRC ends with a trailing separator, it must be a directory. // 3. DST parent directory must exist. // 4. If DST exists as a file, it must not end with a trailing separator. // Check that copying from a container to a local symlink copies to the symlink // target and does not overwrite the local symlink itself. // TODO: move to docker/cli and/or integration/container/copy_test.go func (s *DockerSuite) TestCpFromSymlinkDestination(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{addContent: true}) tmpDir := getTestDir(c, "test-cp-from-err-dst-not-dir") defer os.RemoveAll(tmpDir) makeTestContentInDir(c, tmpDir) // First, copy a file from the container to a symlink to a file. This // should overwrite the symlink target contents with the source contents. srcPath := containerCpPath(containerID, "/file2") dstPath := cpPath(tmpDir, "symlinkToFile1") assert.NilError(c, runDockerCp(c, srcPath, dstPath)) assert.NilError(c, symlinkTargetEquals(c, dstPath, "file1"), "The symlink should not have been modified") assert.NilError(c, fileContentEquals(c, cpPath(tmpDir, "file1"), "file2\n"), `The file should have the contents of "file2" now`) // Next, copy a file from the container to a symlink to a directory. This // should copy the file into the symlink target directory. dstPath = cpPath(tmpDir, "symlinkToDir1") assert.NilError(c, runDockerCp(c, srcPath, dstPath)) assert.NilError(c, symlinkTargetEquals(c, dstPath, "dir1"), "The symlink should not have been modified") assert.NilError(c, fileContentEquals(c, cpPath(tmpDir, "file2"), "file2\n"), `The file should have the contents of "file2" now`) // Next, copy a file from the container to a symlink to a file that does // not exist (a broken symlink). This should create the target file with // the contents of the source file. dstPath = cpPath(tmpDir, "brokenSymlinkToFileX") assert.NilError(c, runDockerCp(c, srcPath, dstPath)) assert.NilError(c, symlinkTargetEquals(c, dstPath, "fileX"), "The symlink should not have been modified") assert.NilError(c, fileContentEquals(c, cpPath(tmpDir, "fileX"), "file2\n"), `The file should have the contents of "file2" now`) // Next, copy a directory from the container to a symlink to a local // directory. This should copy the directory into the symlink target // directory and not modify the symlink. srcPath = containerCpPath(containerID, "/dir2") dstPath = cpPath(tmpDir, "symlinkToDir1") assert.NilError(c, runDockerCp(c, srcPath, dstPath)) assert.NilError(c, symlinkTargetEquals(c, dstPath, "dir1"), "The symlink should not have been modified") assert.NilError(c, fileContentEquals(c, cpPath(tmpDir, "dir1/dir2/file2-1"), "file2-1\n"), `The directory should now contain a copy of "dir2"`) // Next, copy a directory from the container to a symlink to a local // directory that does not exist (a broken symlink). This should create // the target as a directory with the contents of the source directory. It // should not modify the symlink. dstPath = cpPath(tmpDir, "brokenSymlinkToDirX") assert.NilError(c, runDockerCp(c, srcPath, dstPath)) assert.NilError(c, symlinkTargetEquals(c, dstPath, "dirX"), "The symlink should not have been modified") assert.NilError(c, fileContentEquals(c, cpPath(tmpDir, "dirX/file2-1"), "file2-1\n"), `The "dirX" directory should now be a copy of "dir2"`) } // Possibilities are reduced to the remaining 10 cases: // // case | srcIsDir | onlyDirContents | dstExists | dstIsDir | dstTrSep | action // =================================================================================================== // A | no | - | no | - | no | create file // B | no | - | no | - | yes | error // C | no | - | yes | no | - | overwrite file // D | no | - | yes | yes | - | create file in dst dir // E | yes | no | no | - | - | create dir, copy contents // F | yes | no | yes | no | - | error // G | yes | no | yes | yes | - | copy dir and contents // H | yes | yes | no | - | - | create dir, copy contents // I | yes | yes | yes | no | - | error // J | yes | yes | yes | yes | - | copy dir contents // // A. SRC specifies a file and DST (no trailing path separator) doesn't // exist. This should create a file with the name DST and copy the // contents of the source file into it. func (s *DockerSuite) TestCpFromCaseA(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{ addContent: true, workDir: "/root", }) tmpDir := getTestDir(c, "test-cp-from-case-a") defer os.RemoveAll(tmpDir) srcPath := containerCpPath(containerID, "/root/file1") dstPath := cpPath(tmpDir, "itWorks.txt") assert.NilError(c, runDockerCp(c, srcPath, dstPath)) assert.NilError(c, fileContentEquals(c, dstPath, "file1\n")) } // B. SRC specifies a file and DST (with trailing path separator) doesn't // exist. This should cause an error because the copy operation cannot // create a directory when copying a single file. func (s *DockerSuite) TestCpFromCaseB(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{addContent: true}) tmpDir := getTestDir(c, "test-cp-from-case-b") defer os.RemoveAll(tmpDir) srcPath := containerCpPath(containerID, "/file1") dstDir := cpPathTrailingSep(tmpDir, "testDir") err := runDockerCp(c, srcPath, dstDir) assert.ErrorContains(c, err, "") assert.Assert(c, isCpDirNotExist(err), "expected DirNotExists error, but got %T: %s", err, err) } // C. SRC specifies a file and DST exists as a file. This should overwrite // the file at DST with the contents of the source file. func (s *DockerSuite) TestCpFromCaseC(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{ addContent: true, workDir: "/root", }) tmpDir := getTestDir(c, "test-cp-from-case-c") defer os.RemoveAll(tmpDir) makeTestContentInDir(c, tmpDir) srcPath := containerCpPath(containerID, "/root/file1") dstPath := cpPath(tmpDir, "file2") // Ensure the local file starts with different content. assert.NilError(c, fileContentEquals(c, dstPath, "file2\n")) assert.NilError(c, runDockerCp(c, srcPath, dstPath)) assert.NilError(c, fileContentEquals(c, dstPath, "file1\n")) } // D. SRC specifies a file and DST exists as a directory. This should place // a copy of the source file inside it using the basename from SRC. Ensure // this works whether DST has a trailing path separator or not. func (s *DockerSuite) TestCpFromCaseD(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{addContent: true}) tmpDir := getTestDir(c, "test-cp-from-case-d") defer os.RemoveAll(tmpDir) makeTestContentInDir(c, tmpDir) srcPath := containerCpPath(containerID, "/file1") dstDir := cpPath(tmpDir, "dir1") dstPath := filepath.Join(dstDir, "file1") // Ensure that dstPath doesn't exist. _, err := os.Stat(dstPath) assert.Assert(c, os.IsNotExist(err), "did not expect dstPath %q to exist", dstPath) assert.NilError(c, runDockerCp(c, srcPath, dstDir)) assert.NilError(c, fileContentEquals(c, dstPath, "file1\n")) // Now try again but using a trailing path separator for dstDir. assert.NilError(c, os.RemoveAll(dstDir), "unable to remove dstDir") assert.NilError(c, os.MkdirAll(dstDir, os.FileMode(0755)), "unable to make dstDir") dstDir = cpPathTrailingSep(tmpDir, "dir1") assert.NilError(c, runDockerCp(c, srcPath, dstDir)) assert.NilError(c, fileContentEquals(c, dstPath, "file1\n")) } // E. SRC specifies a directory and DST does not exist. This should create a // directory at DST and copy the contents of the SRC directory into the DST // directory. Ensure this works whether DST has a trailing path separator or // not. func (s *DockerSuite) TestCpFromCaseE(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{addContent: true}) tmpDir := getTestDir(c, "test-cp-from-case-e") defer os.RemoveAll(tmpDir) srcDir := containerCpPath(containerID, "dir1") dstDir := cpPath(tmpDir, "testDir") dstPath := filepath.Join(dstDir, "file1-1") assert.NilError(c, runDockerCp(c, srcDir, dstDir)) assert.NilError(c, fileContentEquals(c, dstPath, "file1-1\n")) // Now try again but using a trailing path separator for dstDir. assert.NilError(c, os.RemoveAll(dstDir), "unable to remove dstDir") dstDir = cpPathTrailingSep(tmpDir, "testDir") assert.NilError(c, runDockerCp(c, srcDir, dstDir)) assert.NilError(c, fileContentEquals(c, dstPath, "file1-1\n")) } // F. SRC specifies a directory and DST exists as a file. This should cause an // error as it is not possible to overwrite a file with a directory. func (s *DockerSuite) TestCpFromCaseF(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{ addContent: true, workDir: "/root", }) tmpDir := getTestDir(c, "test-cp-from-case-f") defer os.RemoveAll(tmpDir) makeTestContentInDir(c, tmpDir) srcDir := containerCpPath(containerID, "/root/dir1") dstFile := cpPath(tmpDir, "file1") err := runDockerCp(c, srcDir, dstFile) assert.ErrorContains(c, err, "") assert.Assert(c, isCpCannotCopyDir(err), "expected ErrCannotCopyDir error, but got %T: %s", err, err) } // G. SRC specifies a directory and DST exists as a directory. This should copy // the SRC directory and all its contents to the DST directory. Ensure this // works whether DST has a trailing path separator or not. func (s *DockerSuite) TestCpFromCaseG(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{ addContent: true, workDir: "/root", }) tmpDir := getTestDir(c, "test-cp-from-case-g") defer os.RemoveAll(tmpDir) makeTestContentInDir(c, tmpDir) srcDir := containerCpPath(containerID, "/root/dir1") dstDir := cpPath(tmpDir, "dir2") resultDir := filepath.Join(dstDir, "dir1") dstPath := filepath.Join(resultDir, "file1-1") assert.NilError(c, runDockerCp(c, srcDir, dstDir)) assert.NilError(c, fileContentEquals(c, dstPath, "file1-1\n")) // Now try again but using a trailing path separator for dstDir. assert.NilError(c, os.RemoveAll(dstDir), "unable to remove dstDir") assert.NilError(c, os.MkdirAll(dstDir, os.FileMode(0755)), "unable to make dstDir") dstDir = cpPathTrailingSep(tmpDir, "dir2") assert.NilError(c, runDockerCp(c, srcDir, dstDir)) assert.NilError(c, fileContentEquals(c, dstPath, "file1-1\n")) } // H. SRC specifies a directory's contents only and DST does not exist. This // should create a directory at DST and copy the contents of the SRC // directory (but not the directory itself) into the DST directory. Ensure // this works whether DST has a trailing path separator or not. func (s *DockerSuite) TestCpFromCaseH(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{addContent: true}) tmpDir := getTestDir(c, "test-cp-from-case-h") defer os.RemoveAll(tmpDir) srcDir := containerCpPathTrailingSep(containerID, "dir1") + "." dstDir := cpPath(tmpDir, "testDir") dstPath := filepath.Join(dstDir, "file1-1") assert.NilError(c, runDockerCp(c, srcDir, dstDir)) assert.NilError(c, fileContentEquals(c, dstPath, "file1-1\n")) // Now try again but using a trailing path separator for dstDir. assert.NilError(c, os.RemoveAll(dstDir), "unable to remove resultDir") dstDir = cpPathTrailingSep(tmpDir, "testDir") assert.NilError(c, runDockerCp(c, srcDir, dstDir)) assert.NilError(c, fileContentEquals(c, dstPath, "file1-1\n")) } // I. SRC specifies a directory's contents only and DST exists as a file. This // should cause an error as it is not possible to overwrite a file with a // directory. func (s *DockerSuite) TestCpFromCaseI(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{ addContent: true, workDir: "/root", }) tmpDir := getTestDir(c, "test-cp-from-case-i") defer os.RemoveAll(tmpDir) makeTestContentInDir(c, tmpDir) srcDir := containerCpPathTrailingSep(containerID, "/root/dir1") + "." dstFile := cpPath(tmpDir, "file1") err := runDockerCp(c, srcDir, dstFile) assert.ErrorContains(c, err, "") assert.Assert(c, isCpCannotCopyDir(err), "expected ErrCannotCopyDir error, but got %T: %s", err, err) } // J. SRC specifies a directory's contents only and DST exists as a directory. // This should copy the contents of the SRC directory (but not the directory // itself) into the DST directory. Ensure this works whether DST has a // trailing path separator or not. func (s *DockerSuite) TestCpFromCaseJ(c *testing.T) { testRequires(c, DaemonIsLinux) containerID := makeTestContainer(c, testContainerOptions{ addContent: true, workDir: "/root", }) tmpDir := getTestDir(c, "test-cp-from-case-j") defer os.RemoveAll(tmpDir) makeTestContentInDir(c, tmpDir) srcDir := containerCpPathTrailingSep(containerID, "/root/dir1") + "." dstDir := cpPath(tmpDir, "dir2") dstPath := filepath.Join(dstDir, "file1-1") assert.NilError(c, runDockerCp(c, srcDir, dstDir)) assert.NilError(c, fileContentEquals(c, dstPath, "file1-1\n")) // Now try again but using a trailing path separator for dstDir. assert.NilError(c, os.RemoveAll(dstDir), "unable to remove dstDir") assert.NilError(c, os.MkdirAll(dstDir, os.FileMode(0755)), "unable to make dstDir") dstDir = cpPathTrailingSep(tmpDir, "dir2") assert.NilError(c, runDockerCp(c, srcDir, dstDir)) assert.NilError(c, fileContentEquals(c, dstPath, "file1-1\n")) }