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var expressComposition = require("express-composition")

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express-composition v1.1.0

LoopBack 4 REST API on Express


This is an example of how to mount LoopBack 4 REST API on a simple Express application.


First, you'll need to install a supported version of Node:

Additionally, this tutorial assumes that you are comfortable with certain technologies, languages and concepts.

  • JavaScript (ES6)
  • REST

Lastly, you'll need to install the LoopBack 4 CLI toolkit:

npm i -g @loopback/cli


Once you're ready to start, you can begin by visiting the tutorial page.

Try it out

If you'd like to see the final results of this tutorial as an example application, follow these steps:

Generate the example using CLI

  1. Run the lb4 example command to select and clone the express-composition repository:

    $ lb4 example
    ? What example would you like to clone? (Use arrow keys)
     todo: Tutorial example on how to build an application with LoopBack 4.
     todo-list: Continuation of the todo example using relations in LoopBack 4.
     hello-world: A simple hello-world Application using LoopBack 4.
     log-extension: An example extension project for LoopBack 4.
     rpc-server: A basic RPC server using a made-up protocol.
     soap-calculator: An example on how to integrate SOAP web services.
    > express-composition: A simple Express application that uses LoopBack 4 REST API.
  2. Jump into the directory and then install the required dependencies:

    cd loopback4-example-example-composition
  3. Finally, start the application!

    $ npm start
    Server is running at

Feel free to look around in the application's code to get a feel for how it works.


Run npm test from the root folder.




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