Client

Installation

npm install -g @eik/cli

Quickstart guide

Step 1.

Generate an eik.json file in the current directory

eik init

Fill in the generated eik.json file with the necessary details.

For the server property, you will need to have set up and know the address to, and Eik asset server. See the server docs

Set the files property of eik.json with paths to client side asset files in your project relative to the eik.json file. Eg. if you have a scripts.js file in an assets directory, the js.input value will be assets/scripts.js

Step 2

Run publish to publish your assets to the server

eik publish

Additional tasks

Publishing global dependencies

When you wish to share a version of a module, you can use the dependency command to do so.

This feature does the following:

• converts a module already published to npm to esm
• makes it available through the asset server

Example use case

You might decide that all teams across your organisation should use the same version of lodash via a published URL (rather than each team bundling their own version).

To do so you would run:

eik dependency lodash 4.17.15

After running this, an esm friendly version of lodash will be available at the url: http://<asset server url>/pkg/lodash/4.17.15

It's now possible for each team to reference this globally published module directly in their own client side code as follows:

import lodash from `http://<asset server url>/pkg/lodash/4.17.15`;

This has the benefit that if all teams are referencing lodash in this way, the browser will cache the module the first time it encounters it and on subsequent pages will not need to download it again.

Aliasing published modules

Aliasing allows you to tag specific published versions of modules with a more general tag or version that you are also able to centrally change as needed.

The benefit of this is that you can alias a specific version of a dependency and then update that alias overtime as you publish new versions of the dependency and have all dependents immediately receive the change.

Example use case

Taking the previous example 1 step further, before we saw that we could globally publish a specific version of lodash, in this case 4.17.15.

We can now set a major semver alias for this version:

eik alias lodash 4.15.15 4

We can now change our import statement to:

import lodash from `http://<asset server url>/pkg/lodash/v4`;

and everything will work as before.

When a new version of lodash comes out, we can create a global dependency for it as before:

eik dependency lodash 4.17.16

And then update the major semver alias to the new version like so:

eik alias lodash 4.15.16 4

In this way, no client side code will need to be updated to reflect this change and it is considerably easier for multiple teams to stay in sync, using the same global shared dependency

Using import maps to map "bare imports"

Import maps are an emerging standard and a way to map "bare imports" such as foo in the import statement import { bar, baz } from 'foo' to modules to be loaded. With Eik, we provide a way to upload import map files and to specify them for use in bundling. Doing so allows you to specify a common set of shared modules, whether they be react or lit-html etc.

Making use of import maps is done as follows.

1. Define an import map json file
2. Use the Eik CLI to upload the import map to the server
3. Specify the URL to your import map file(s) in your eik.json file
4. Use the publish commands, your import maps will be used to map bare imports in your code to the URLs you have defined in your import maps

Import maps, an example

Given the following import map file import-map.json

{
  "imports": {
    "lit-html": "http://assets.examplecdn.com/pkg/lit-html/v1/index.js",
    "lodash": "http://assets.examplecdn.com/pkg/lodash/v4/index.js"
  }
}

The following command will upload the import map file ./import-map.json in the current directory using the name my-import-map and the version 1.0.0

eik map my-import-map 1.0.0 ./import-map.json

Given the following line now added to eik.json

{
  "import-map": ["http://assets.examplecdn.com/map/my-import-map/1.0.0"]
}

When we run eik publish any "bare imports" refering to either lit-html or lodash will be mapped to the URLs in our map.

In this way, you can control which version of react or lit-html or lodash all your apps are using. In combination with package alias URLs, you have a powerful way to manage key shared dependencies for your apps in production without the need to redeploy or rebundle when a new version of a dependency is released.

Accessing meta information about a package

It's possible to access information about a published package with the meta command. The command returns information in JSON format.

Example

eik meta lodash 4.17.16

API Documentation

Command Summary

command	aliases	description
init	i	Create an eik.json file in the current directory
login		Authenticates client with eik server
ping		Pings eik server
publish	p, pub	Publish an app bundle
dependency	d, dep	Publish a dependency bundle
map	m	Sets or deletes a "bare" import entry in an import-map file
alias	a	Sets a major semver alias for a given dependency or map
meta	show	Retrieves meta information for a package

Commands Overview

init

This command takes no input and creates a new eik.json file in the current directory with the following content:

{
  "name": "",
  "server": "",
  "js": {
    "input": "",
    "options": {}
  },
  "css": {
    "input": "",
    "options": {}
  },
  "import-map": []
}

You will then need to set the various fields as appropriate. If you are running a local asset server, the default server url should be http://localhost:8080.

eik.json properties

property	description
name	App name, must be unique to the Eik server
server	Address to the asset server
js	Configuration for JavaScript assets
css	Configuration for CSS assets
import-map	Specify import maps to be used to map bare imports during bundling

name

All asset uploads must have a name. When publishing a dependency from npm the name will be the package name taken from the module's package.json file. When publishing the assets for your app, the name field of your project's eik.json file is used. Names may contain any letters or numbers as well as the - and _ characters.

{
  "name": "my-awesome-app"
}

server

This is the address to the asset server you are using. This might be a locally running version of the asset server (usually http://assets.examplecdn.com) or an asset server running in production (TBD)

{
  "server": "http://assets.examplecdn.com"
}

js

This field is used to configure bundling and publishing of JavaScript assets. Use js.input to configure the location on disk, relative to eik.json, where the entrypoint for your JavaScript client side assets are located.

scripts.js file inside assets folder

{
  "js": {
    "input": "./assets/scripts.js"
  }
}

css

This field is used to configure bundling and publishing of CSS assets. Use css.input to configure the location on disk, relative to eik.json, where the entrypoint for your CSS client side assets are located.

styles.css file inside assets folder

{
  "css": {
    "input": "./assets/styles.css"
  }
}

import-map

This field is used to configure the location of any import map files to be used when creating bundles. The field should be an array and can hold any number of url strings pointing to locations of import-map files that will be downloaded and merged together

defining a single import map file

{
  "import-map": ["http://assets.examplecdn.com/map/my-import-map/1.0.0"]
}

login

Authenticate with the configured Eik server. The server field in eik.json will be used to determine which server to authenticate with. It is also possible to set the server without the need for an eik.json file using the command line flag --server or -s

The command takes the form:

eik login [optional arguments]

Example

Authenticate with Eik server using a prompt

eik login

Authenticate with Eik server using a given key

eik login --key some_key

ping

Ping the configured Eik server.

Example

Ping Eik server

eik ping

publish

This command publishes the app's client side assets to an Eik server based on the values in an eik.json file in the current directory.

The command takes the form:

eik publish [optional arguments]

Example

Publishing app assets to server

eik publish

dependency

This command will download the specified (by name and version) package from NPM, create a bundle with it and then publish it to the Eik server. The resulting bundle will be in esm module format, converting from common js if needed.

Note The arguments server and import-map are taken from eik.json if such a file is present in the current directory. If not, you will need to specify these values with the command line flags --server and --map.

The command takes the form:

eik dependency [optional arguments] <name> <version>

Example

Publishing a dependency from npm

eik dependency lit-html 1.1.2
# eik dependency --server http://assets.examplecdn.com --map http://assets.examplecdn.com/finn/map/my-import-map/1.0.0 lit-html 1.1.2

alias

This command creates a semver alias for a given published bundle. Creating aliases allows for more flexible referencing of published bundles. You can update an alias to point to the latest version of a bundle without needing to update every client that makes use of your bundle.

Note The server argument is taken from eik.json if such a file is present in the current directory. If not, you will need to specify this values with the command line flag --server.

The command takes the form:

eik alias [optional arguments] <name> <version> <alias>

Example

Running the following command...

eik alias lit-html 1.1.2 1
# eik alias --server http://assets.examplecdn.com lit-html 1.1.2 1

...will create or update the lit-html alias 1 to point at lit-html version 1.1.2

map

This command uploads an import map json file you have created locally to the server. You must upload the file with a name and a version and the file must be of the form:

{
  "imports": {
    "<dependency name 1>": "url to dependency",
    "<dependency name 2>": "url to dependency"
  }
}

Note The argument server is taken from eik.json if such a file is present in the current directory. If not, you will need to specify this value with the command line flag --server.

The command takes the form:

eik map [optional arguments] <name> <version> <path to file>

eik map my-import-map 1.0.0 ./import-map.json
# eik map --server http://assets.examplecdn.com my-import-map 1.0.0 ./import-map.json

meta

This command fetches and displays meta information about a package from the server

The command takes the form:

eik meta [optional arguments] <name> <version>

Example

Running the following command...

eik meta lit-html 1.1.2
# eik meta --server http://assets.examplecdn.com lit-html 1.1.2

Will print meta information about the package lit-html version 1.1.2 in JSON format.

Programmatic Usage

All of the commands described above can be used programmatically by importing this package. Each command and its programmatic usage is given below.

init

const cli = require("@eik/cli");
const result = await new cli.Init(options).run();

options

name	description	type	default	required
logger	log4j compliant logger object	object	null	no
cwd	path to current working directory	string	process.cwd()	no
name	app name	string	''	no
server	URL to asset server	string	''	no
js	path to client side script entrypoint	string	''	no
css	path to client side style entrypoint	string	''	no

publish

const cli = require("@eik/cli");
const result = await new cli.publish.App(options).run();

options

name	description	type	default	required
logger	log4j compliant logger object	object	null	no
cwd	path to current working directory	string	process.cwd()	no
name	app name	string		yes
server	URL to asset server	string		yes
js	path to client side script entrypoint	string		yes
css	path to client side style entrypoint	string		yes
map	array of urls of import map files	string[]	[]	no
dryRun	exit early and print results	boolean	false	no

dependency

const cli = require("@eik/cli");
const result = await new cli.publish.Dependency(options).run();

options

name	description	type	default	required
logger	log4j compliant logger object	object	null	no
cwd	path to current working directory	string	process.cwd()	no
name	app name	string		yes
server	URL to asset server	string		yes
map	array of urls of import map files	string[]	[]	no
dryRun	exit early and print results	boolean	false	no

map

const cli = require("@eik/cli");
const result = await new cli.publish.Map(options).run();

options

name	description	type	default	required
logger	log4j compliant logger object	object	null	no
cwd	path to current working directory	string	process.cwd()	no
name	app name	string		yes
version	app version	string		yes
server	URL to asset server	string		yes
file	path to import map file to be uploaded	string		yes

alias

const cli = require("@eik/cli");
const result = await new cli.Alias(options).run();

options

name	description	type	default	choices	required
logger	log4j compliant logger object	object	null		no
server	URL to asset server	string			yes
type	type of resource to alias	string		pkg, map	yes
name	app name	string			yes
alias	major number of a semver version number	string			yes

meta

const cli = require("@eik/cli");
const result = await new cli.Meta(options).run();

name	description	type	default	choices	required
logger	log4j compliant logger object	object	null		no
server	URL to asset server	string			yes
name	package name	string			yes