GazeboJs is a C++ addon to Node.js that is loaded inside node process at runtime (using the
This is the same mechanism that the Gazebo simulation client (the gzclient process) uses to communicate with the simulation server.
The source code for this project can be found here: https://bitbucket.org/osrf/gazebojs
This page explains how to install the GazeboJs Node bindings to Gazebo.
This tutorial shows how to download, install and compile Gazebojs on a computer where Gazebo and its development libraries are installed. Please refer to the Install Gazebo on Mac (using homebrew).
The homebrew install of Gazebo also install the corresponding development libraries (for example, libgazebo6-dev for Gazebo 6). The dev libraries also contain the Gazebo header files that are necessary for the gazebojs installation. This is because the Node.js Gazebo modules are automatically compiled on your machine when the
npm install gazebojs is invoked (see below).
Like Gazebo, gazebojs module uses semantic versioning, so the major version of gazebojs should be the same as the major version of Gazebo you are using. You can specify rules about the version of gazebojs you want to use in the
package.json file (see https://www.npmjs.org/doc/files/package.json.html).
Install Node.js and npm
brew search node
This might give you the following results
homebrew/versions/node012 homebrew/versions/node010 homebrew/versions/node08 homebrew/versions/node06 homebrew/versions/node04 node nodebrew leafnode nodenv
Gazebo 6 is compatible with node 0.10 (which is the version of node that is bundled with Ubuntu 14.04). The following versions have been found to work well together: node v0.10.40, npm 2.14.4 (node package manager), and Gazebo 6.4.
To install node:
brew install homebrew/versions/node010
The above command also installs npm. To check your installed version:
npm --version node --version gazebo --version
Install the required libraries
brew install jpeg brew install pkg-config brew install jansson
Make sure that these packages can be found in your pkg-config path. This is because gazebojs uses pkg-config. You can check this by executing this command without any error:
pkg-config --cflags gazebo jansson protobuf || echo "error :-("
error :-( is printed at the end then one or more of the packages can not be found.
Now that everything is installed, here are the steps to test it:
Create a Node.js project directory
mkdir gz_node_inst cd gz_node_inst npm init
Npm will prompt you for details about your project. You can add information or press ENTER a few times. This step creates a package.json directory. Having a package.json file in your local directory will also ensure that npm will install all its packages in your local directory.
npm install gazebojs --save
This operation should download and compile the latest gazebojs. There is a C++
compilation phase where a Node.js module is created. There should now be a
node_modules directory created in your project directory.
Test your installation:
Launch Gazebo in a separate terminal and verify that the simulation is running (when simulation is running, the
Sim Time increases in the status bar in the bottom of the screen):
Use the 'node' command (from the same directory where you invoked the npm command) to invoke the Node.js REPL console
Type in the following commands to load the gazebojs module, create a
simulation client and pause the running simulation. Note that the
undefined messages are Node.js console valid responses to your command.
> var gazebojs = require('gazebojs') undefined > var sim = new gazebojs.Gazebo() undefined > sim.pause() undefined
You should see the simulation become paused in Gazebo.
Problem: Npm error about incompatible version
npm http 304 https://registry.npmjs.org/which npm ERR! Error: No compatible version found: mkdirp@'^0.5.0' npm ERR! Valid install targets: npm ERR! ["0.0.1","0.0.2","0.0.3","0.0.4","0.0.5","0.0.6","0.0.7","0.1.0","0.2.0","0.2.1","0.2.2","0.3.0","0.3.1","0.3.2","0.3.3","0.3.4","0.3.5","0.4.0","0.4.1","0.4.2","0.5.0","0.5.1"] npm ERR! at installTargetsError (/usr/local/lib/node_modules/npm/lib/cache.js:685:10) npm ERR! at /usr/local/lib/node_modules/npm/lib/cache.js:607:10 npm ERR! at saved (/usr/local/lib/node_modules/npm/node_modules/npm-registry-client/lib/get.js:138:7) npm ERR! at FSReqWrap.oncomplete (fs.js:82:15)
Solution: check that your npm version is above 1.4.3
Problem: missing jpeg
> node-gyp rebuild CXX(target) Release/obj.target/canvas/src/Canvas.o In file included from ../src/Canvas.cc:19: ../src/JPEGStream.h:11:10: fatal error: 'jpeglib.h' file not found #include <jpeglib.h> ^ 1 error generated. make: *** [Release/obj.target/canvas/src/Canvas.o] Error 1 gyp ERR! build error gyp ERR! stack Error: `make` failed with exit code: 2 gyp ERR! stack at ChildProcess.onExit (/usr/local/lib/node_modules/npm/node_modules/node-gyp/lib/build.js:267:23) gyp ERR! stack at ChildProcess.EventEmitter.emit (events.js:98:17) gyp ERR! stack at Process.ChildProcess._handle.onexit (child_process.js:789:12) gyp ERR! System Darwin 13.0.0
brew uninstall jpeg && brew install jpeg
Jpeg is also part of the xcode command line tools. You can try:
It is good to try to use a new bash terminal after jpeg installation, in case the path to the library has not been set for the compiler/linker.
Problem: linker error, ld: library not found for -lgcc_s.10.5
> email@example.com install /Users/Kyle/Documents/Software/mean/mean_scotch/node_modules/bcrypt > node-gyp rebuild CXX(target) Release/obj.target/bcrypt_lib/src/blowfish.o CXX(target) Release/obj.target/bcrypt_lib/src/bcrypt.o CXX(target) Release/obj.target/bcrypt_lib/src/bcrypt_node.o SOLINK_MODULE(target) Release/bcrypt_lib.node ld: library not found for -lgcc_s.10.5 collect2: error: ld returned 1 exit status make: *** [Release/bcrypt_lib.node] Error 1 gyp ERR! build error gyp ERR! stack Error: `make` failed with exit code: 2
Solution: add the missing libraries in your '/usr/local/lib' directory
cd /usr/lib sudo ln -s ../lib/libSystem.B.dylib libgcc_s.10.5.dylib
Another (better) solution is to (re) install Xcode 7.