Script to flatten message directories

Adds a new script that will copy all of your message
dependencies into a specified location, flattening the
directory structure. It will also parse through your files
and update their require paths to take advantage of this
new directory structure.

Author: chris-smith

flatten.js

@@ -0,0 +1,16 @@
+'use strict'
+
+// a utility script that will flatten the directory structure for the message
+// files generated by genjs.
+
+let message_utils = require('./utils/message_utils.js');
+
+let args = process.argv;
+console.log(args);
+
+if (args.length < 3) {
+  throw new Error('Must include desired output directory in calls to flatten!');
+}
+
+message_utils.findMessageFiles();
+message_utils.flatten(args[2]);

package.json

@@ -9,7 +9,8 @@
     "js"
   ],
   "scripts": {
-    "test": "mocha --recursive"
+    "test": "mocha --recursive",
+    "flatten": "node flatten.js"
   },
   "author": "chris smith",
   "license": "Apache-2.0",

utils/message_utils.js

@@ -19,14 +19,15 @@
 
 let fs = require('fs');
 let path = require('path');
+let utils = require('util');
 let log = require('./logger.js').createLogger();
 
 // When sourcing your workspace, CMAKE_PREFIX_PATH is AUTOMATICALLY
 // prepended with the devel directory of your workspace. Workspace
 // chaining works by continuing this path prepending.
 let cmakePath = process.env.CMAKE_PREFIX_PATH;
 let cmakePaths = cmakePath.split(':');
-let jsMsgPath = 'share/node_js/ros';
+let jsMsgPath = path.join('share', 'node_js', 'ros');
 
 let messagePackageMap = {};
 let messagePackagePathMap = {};
@@ -41,6 +42,51 @@ let messagePackagePathMap = {};
 //  in the cache and require it if found.
 //-----------------------------------------------------------------------
 
+function createDirectory(directory) {
+  let curPath = '/';
+  const paths = directory.split(path.sep);
+  paths.forEach((part, index) => {
+    if (!part) {
+      return;
+    }
+    curPath = path.join(curPath, part);
+    const thisPath = curPath;
+
+    try {
+      fs.mkdirSync(thisPath);
+    }
+    catch (err) {
+      if (err.code !== 'EEXIST') {
+        throw err;
+      }
+    }
+  });
+}
+
+function copyFile(from, to, replaceCallback) {
+  return new Promise((resolve, reject) => {
+    const readStream = fs.createReadStream(from);
+    let fileData = '';
+    readStream.on('data', (data) => {
+      fileData += data;
+    });
+
+    readStream.on('end', () => {
+      if (typeof replaceCallback === 'function') {
+        fileData = replaceCallback(fileData);
+      }
+
+      // open the output file for writing
+      const writeStream = fs.createWriteStream(to);
+      writeStream.on('open', () => {
+        writeStream.write(fileData);
+        writeStream.end();
+        resolve();
+      });
+    });
+  });
+}
+
 let MessageUtils = {
   findMessageFiles() {
     if (Object.keys(messagePackagePathMap).length > 0) {
@@ -62,6 +108,78 @@ let MessageUtils = {
     });
   },
 
+  flatten(outputDir) {
+    const finderDeclRegex = /^let _finder = require\('\.\.\/\.\.\/\.\.\/find\.js'\);/m;
+    const finderCallRegex = /^let (\w+) = _finder\(\'\1\'\);/gm;
+
+    const flatten_local = (packageName, startPath, localPath, outputDir) => {
+      const flattenPath = path.join(startPath, localPath);
+      fs.readdir(flattenPath, (err, files) => {
+        if (err) {
+          // if the path doesn't exist, it just means the package currently
+          // being flattened doesn't have either msgs or srvs
+          if (err.code !== 'ENOENT') {
+            throw new Error('Error while flattening generated messages ' + err);
+          }
+          return;
+        }
+        // else
+        const outputPath = path.join(outputDir, packageName, localPath);
+        createDirectory(outputPath)
+
+        files.forEach((file) => {
+          const filePath = path.join(flattenPath, file);
+          const outputFilePath = path.join(outputDir, packageName, localPath, file);
+          let callback;
+          if (file !== '_index.js') {
+            callback = (fileData) => {
+              fileData = fileData.replace(finderDeclRegex, '');
+              let matchData;
+              while ((matchData = finderCallRegex.exec(fileData)) !== null) {
+                const matchStr = matchData[0];
+                const msgPackage = matchData[1];
+                const replaceStr = utils.format('let %s = require(\'../../%s/_index.js\');', msgPackage, msgPackage);
+                fileData = fileData.replace(matchStr, replaceStr);
+              }
+              return fileData;
+            };
+          }
+          copyFile(filePath, outputFilePath, callback);
+        });
+      });
+    };
+
+    outputDir = path.resolve(outputDir);
+    const messageDirectory = path.join(outputDir, 'ros');
+    createDirectory(messageDirectory);
+
+    // find relevant genjs base files and copy to output directory
+    const filesToCopy = ['base_deserialize.js', 'base_serialize.js'];
+    cmakePaths.some((cmakePath) => {
+      const checkPath = path.join(cmakePath, 'share', 'node_js');
+      let files = fs.readdirSync(checkPath);
+      if (!files) {
+        return false;
+      }
+      files.forEach((fileName) => {
+        if (filesToCopy.indexOf(fileName) !== -1) {
+          copyFile(path.join(checkPath, fileName), path.join(outputDir, fileName));
+        }
+      });
+      return true;
+    });
+
+    Object.keys(messagePackagePathMap).forEach((packageName) => {
+      const messagePackagePath = messagePackagePathMap[packageName];
+      const dir = path.dirname(messagePackagePath)
+
+      flatten_local(packageName, dir, 'msg', messageDirectory);
+      flatten_local(packageName, dir, 'srv', messageDirectory);
+      // copy the index
+      copyFile(messagePackagePath, path.join(messageDirectory, packageName, '_index.js'));
+    });
+  },
+
   loadMessagePackage(msgPackage) {
     const indexPath = messagePackagePathMap[msgPackage];
     if (indexPath === undefined) {