org.sonatype.gshell.commands.vfs.EditCommand.java Source code

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Here is the source code for org.sonatype.gshell.commands.vfs.EditCommand.java

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/*
 * Copyright (c) 2009-2013 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.sonatype.gshell.commands.vfs;

import org.apache.commons.vfs.FileObject;
import org.apache.commons.vfs.Selectors;
import org.apache.commons.vfs.util.Os;
import org.sonatype.gshell.command.Command;
import org.sonatype.gshell.command.CommandContext;
import org.sonatype.gshell.util.cli2.Argument;
import org.sonatype.gshell.util.cli2.Option;
import org.sonatype.gshell.vfs.FileObjectAssert;
import org.sonatype.gshell.vfs.FileObjects;

import java.io.File;
import java.util.Arrays;
import java.util.List;

/**
 * Edit a file with an external editor.
 *
 * @author <a href="mailto:jason@planet57.com">Jason Dillon</a>
 * @since 2.0
 */
@Command(name = "vfs/edit")
public class EditCommand extends VfsCommandSupport {
    @Option(name = "e", longName = "editor")
    private String editor;

    @Argument(required = true)
    private String path;

    public Object execute(final CommandContext context) throws Exception {
        assert context != null;

        FileObject file = resolveFile(context, path);

        new FileObjectAssert(file).exists().isReadable().isWritable();

        // TODO: Add to FileObjectAssert
        ensureFileHasContent(file);

        FileObject tmp = file;

        // If the file is not on the local file system, then create tmp file for editing
        if (!getFileSystemAccess().isLocalFile(file)) {
            // Create a new temporary file, copy the contents for editing
            tmp = resolveFile(context, "tmp:/gshell-edit-" + System.currentTimeMillis() + ".txt");
            log.debug("Using temporary file: {} ({})", tmp, tmp.getClass());
            tmp.createFile();
            tmp.copyFrom(file, Selectors.SELECT_SELF);
        }

        // Have to dereference the VFS file into a local file so the editor can access it
        File localFile = getFileSystemAccess().getLocalFile(tmp);
        Object result = edit(context, localFile);

        // If we had to use a tmp file for editing, then copy back and clean up
        if (tmp != file) {
            log.debug("Updating original file with edited content");
            file.copyFrom(tmp, Selectors.SELECT_SELF);
            tmp.delete();
            FileObjects.close(tmp);
        }

        FileObjects.close(file);

        return result;
    }

    private Object edit(final CommandContext context, final File localFile) throws Exception {
        assert context != null;
        assert localFile != null;

        log.debug("Editing file: {}", localFile);

        List<String> editorCmd = selectEditor();

        log.debug("Executing: {} {}", editorCmd, localFile);

        ProcessBuilder builder = new ProcessBuilder();
        for (String s : editorCmd) {
            builder.command().add(s);
        }
        builder.command().add(localFile.getAbsolutePath());

        Process p = builder.start();

        log.debug("Waiting for process to exit...");
        int status = p.waitFor();
        log.info("Process exited w/status: {}", status);

        return status;
    }

    private List<String> selectEditor() {
        String cmd;

        if (editor != null) {
            cmd = editor;
        } else {
            // TODO: Expose a configurable preference for this
            cmd = getDefaultEditor();
        }

        // The editor configuration may need to set arguments or whatever, so we have to return a list
        return Arrays.asList(cmd.split("\\s"));
    }

    private String getDefaultEditor() {
        if (Os.isFamily(Os.OS_FAMILY_WINDOWS)) {
            return "NOTEPAD";
        } else if (Os.isFamily(Os.OS_FAMILY_UNIX)) {
            if (System.getenv("DISPLAY") != null) {
                String tmp = System.getenv("XEDITOR");
                if (tmp != null) {
                    return tmp;
                }
            }

            String tmp = System.getenv("EDITOR");
            if (tmp != null) {
                return tmp;
            }

        }

        throw new RuntimeException("Unable to determine the default editor command");
    }
}