Quick Start

System requirements

To create an application with ZetaPush you only need the Node.js ecosystem:

Node.js version 8.11.2 (LTS) or higher
npm version 5.x or higher

Node.js is used to:

create custom cloud services
locally run custom cloud services
deploy your application on ZetaPush

Install Node.js and npm

Go to Node.js Downloads and follow the installation instructions.

You also need to install additional tools for Node.js:

Additional tools

Windows

You must install development tools on Windows (Visual Studio Build Tools and Python). Fortunately, there is a npm tool that helps you to install all required dependencies. You must run this command line using PowerShell as Administrator:

npm install --global --production windows-build-tools

Be patient! It may take a while.

Debian/Ubuntu

Install build tools:

sudo apt-get install -y build-essential

Enterprise Linux and Fedora

Install build tools:

sudo yum install gcc-c++ make
# or: sudo yum groupinstall 'Development Tools'

Create your first application

From the command line

Generate application

$ npm init @zetapush first-hello-world (1)

1	first-hello-world is the name of the folder that will be created with all the generated files

You will be prompted for a developer login and a developer password in order to create a new account.

The developer login and the developer password will be stored in the .zetarc file. By default, the .gitignore file is configured to not deploy this file.

Using npm lower than 6

npm provides npm init command since version 6.

You can either upgrade your npm version or use npx utility.

npm 5-

Upgrade npm

➊ - Upgrade npm

$ npm install -g npm@latest

➋ - Use npm init

$ npm init @zetapush first-hello-world

Use npx to launch the script

Launch with npx

$ npx @zetapush/create first-hello-world

See ZetaPush account management to learn how to manage your account and your applications.

Generated project

Figure 1. Result of first-hello-world project

The project first-hello-world generated by the CLI is available on Github. This sample is also available using different front frameworks:

What it does ?

The generated project is really simple. It is just a web page that uses some JavaScript to call a cloud function named hello when button is clicked. The cloud function is a custom cloud function that simply returns a message with the current date. The result is retrieved by the JavaScript code and displayed in the browser console (using console.log).

Structure of generated project

The files of the generated project are structured as followed:

Generated tree structure

{appName}
├── .zetarc
├── .gitignore
├── front
│   ├── index.css
│   ├── index.html
│   ├── index.js
│   └── logo.png
├── worker
│   └── index.ts
├── package.json
├── README.md
└── tsconfig.json

Table 1. Definition of generated files
File / Folder	Definition
`.zetarc`	Contains the developer’s credentials. Useful to deploy or run your code. The content is auto generated if the file is empty.
`.gitignore`	Standard file used by Git to prevent commiting some files. It is preconfigured to prevent publication of your developer credentials (on GitHub for example).
`package.json`	Standard file for NPM to handle a module. It contains the dependencies, the name of your application, the entry point of your custom cloud services (`main` property) and many useful other informations for your application.
`README.md`	Gives you some information about how to use your application.
`front/`	By convention, the front end code of your application is in this folder. You can change it by editing `package.json`.
`worker/`	By convention, the back end code of your application is in this folder. You can change it by editing `package.json`.

Run locally your first project

What is run ?

Run is used in development phase. You run your code locally on your development machine. You can then iterate on your code to provide new features quickly or even debug your code.

From your terminal

Go into the generated folder (first-hello-world):

$ cd first-hello-world

Then run the following command:

Start application (front and custom cloud services)

$ npm run start -- --serve-front

npm run start is a script alias defined in the package.json file. The command that is executed under the hood is:

$ zeta run --serve-front

This command launches both a local web server on localhost:3000 and the custom cloud services. You can open a web browser on localhost:3000 and open the browser console.

You can click on the button and see the result of the custom cloud service call in the browser console.

How it works

Figure 2. Exchanges between web page and custom cloud services

➊ Clicking on the button triggers a call to the ZetaPush cloud. ZetaPush routes the call to the local Node.js (the Node.js has been registered automatically by the CLI)
➋ The custom cloud service does its job and provides a response. ZetaPush routes the response to the connected web page

There are 3 parts that are working together:

The web page that initiates a connection to the ZetaPush cloud
The ZetaPush cloud
The worker that provides the custom cloud function implementation

Firstly, the web page is loaded in the browser and a JavaScript code automatically connects the ZetaPush client to the ZetaPush cloud.

The connection is requested with client.connect() in first-hello-world/front/index.html.

The connection between ZetaPush client and the ZetaPush cloud is established and is bi-directional. Any message sent by ZetaPush client will go through this opened connection. The ZetaPush cloud can also send messages to the ZetaPush client through this opened connection.

Then, when the user clicks on the button, a message is sent to the ZetaPush cloud in order to execute some code. The ZetaPush cloud routes the message to the worker to call the custom cloud function.

The button is defined in first-hello-world/front/index.html

The action of the button is done in first-hello-world/front/index.js and it calls api.hello().

The custom cloud function is simply a JavaScript or TypeScript function. This function is called and it generates a result that is returned to ZetaPush cloud. ZetaPush cloud routes the response message to the ZetaPush client to send the result.

The code of the cloud function is available in first-hello-world/worker/index.ts

Finally, the ZetaPush client receives the result and the JavaScript code of the web page displays it in the browser console (using console.log).

The result is handled in first-hello-world/front/index.js.

Even if you run locally, the cloud functions defined by your worker are available on the Internet through ZetaPush cloud.

Push your first project in the Cloud

What is push ?

Push is used to make your code "public". It will publish your web page(s) and also upload the code of your worker on ZetaPush cloud. You can push when you think that your code is ready to be used by your end-users.

From your terminal

Deploy application (front and custom cloud services)

$ npm run deploy

npm run deploy is a script alias defined in the package.json file. The command that is executed under the hood is:

$ zeta push

This command uploads your code (front and worker) to the ZetaPush cloud. ZetaPush then handles the deployment by publishing your front and your custom cloud services.

The CLI displays the URL to access the published web page.

How it works

Figure 3. Exchanges between web page and custom cloud services

➊ Clicking on the button triggers a call to the ZetaPush cloud which in turn routes directly the call to the hosted Node.js
➋ The custom cloud service does its job and provides a response that ZetaPush routes back to the hosted web page

Now, the web page (front) and the custom cloud functions (defined in a worker) are hosted directly on ZetaPush cloud. The behavior remains the same as when code is executed local machine:

There are still the same 3 parts working together (web page, ZetaPush cloud and custom cloud function)
There is still a connection established by the client from the web page
There is still a message sent by the client to ZetaPush cloud that is routed to call the custom cloud function
There is still a message sent by the ZetaPush cloud that is routed to the client with the result of the custom cloud function

What’s next

You have created a new application, executed it locally and then published it.

Now, you are ready to code your own application: