custom-svg-to-ts v1.0.0

• What is svg-to-ts?
• Who is this for?
• Why you should use svg-to-ts
• Step by step guide on how to create your icon library
  • Video tutorials
  • Writtern tutorial
• How to use svg-to-ts
  • Usage
    • Command line
    • Configuration in package.json or .rc file
    • Configuration in a .js file
      • Configure svg-to-ts over package.json
      • Configure svg-to-ts over .rc file
  • ConversionTypes
    • 1. Converting to a single object (conversionType==='object')
      • Available options:
      • Example usage
      • Sample output
    • 2. Multiple constants - Treeshakable and typesafe with one file (conversionType==='constants')
      • Available options:
      • Example usage
      • Sample ouput
    • 3. Tree shakable and optimized for lazy loading (conversionType==='files')
      • Available options:
      • Example usage
      • Sample output
• SVGO - SVG optimization
• Starter project
• Angular builder
• FAQ
  • Which approach should I use
  • Is it possilbe to create a standalone library?
  • Can I use the icons to generate a type?
• Contributors ✨

What is svg-to-ts?

svg-to-ts is a helper tool that converts your SVG icons to TypeScript. svg-to-ts can convert SVGs to either one TypeScript file with exported constants, multiple TypeScript files or compiled JavaScript files with according declaration files. Furthermore it generates all typings in form of interfaces and types.

The generated output can then be used in combination with a iconregistry to create a tree shakable icon library. (More informations...)

Who is this for?

svg-to-ts is designed for autors of component libraries or icon libraries. Our examples and tutorials are made with Angular, however svg-to-ts can also be used with other frameworks or vanilla TypeScript / JavaScript.

Why you should use svg-to-ts

• svg-to-ts helps you provide icons in a tree shakable and performant way.
• You get free step to step guides in form of blog posts, that walk you through the process of creating your own tree shakable icon library
• svg-to-ts optimizes your SVG icons under the hood
• svg-to-ts automatically generates types and interfaces for your icons to improve typesafety
• svg-to-ts was developed based on the experiences of providin an icon library for a large enterprise.
• offers three different conversion modes ('object', 'constants' and 'files')
• each method is highly configurable to supports multiple use cases.

Step by step guide on how to create your icon library

We created multiple tutorials to show you how you can use svg-to-ts in the best way. We have two step by step guides. A video course and a blog post. Both cover the same content. Feel free to choose the format you prefer.

Video tutorials

Writtern tutorial

This blog post guides you through the process of building your own icon library with svg-to-ts.

How to use svg-to-ts

svg-to-ts is a command line tool, it can either be used directly in your terminal or via npm script.

Usage

Command line

To execute svg-to-ts on the commmand line simply run npx svg-to-ts --help to see a list of available parameters. Once you know which parameters to use, you can use npx to execute svg-to-ts and pass some parameters to it. For example, if you want to convert all SVG file in your current folder to TypeScript constants. npx svg-to-ts -s './*.svg'.

Configuration in package.json or .rc file

When you start using svg-to-ts in bigger projects, configuration may get more sophisticated. At this point command line arguments are hard to read. Therefore svg-to-ts allows you to configure it either over package.json or over a .svg-to-tsrc file.

Those files can be written in json, yaml, yml, js (CommonJS module). By default svg-to-ts will search up the directory tree for a svg-to-ts property in the package.json, a .svg-to-tsrc file. However, if you are working in a monorepo or want to have multiple configs, you can use the --config property to specify a path your configuration. For example svg-to-ts --config ./myconfig.json.

Configuration in a .js file

An alternative for bigger projects is to use a JavaScript-based configuration file. The main advantage here is there you can create dynamic configurations, but also use plain-old JavaScript objects, allowing you to add comments, etc. This is useful for more complex configurations where comments can clarify why options are defined in a certain way.

As stated in the previous section, JS configurations must be defined as a CommonJS module.

Here's an example:

const svgToTsConfig = {
  srcFiles: ["./libs/web-icons/icons/**/*.svg"],
  conversionType: "files",
  outputDirectory: "./libs/web-icons/src/lib",
  interfaceName: "MyIcon",
  typeName: "MyIconName",
  generateType: true,
  modelFileName: "whatever-icon.model",
  additionalModelFile: "./libs/web-icons/src/lib",
  iconsFolderName: "generated",
  delimiter: "SNAKE",
  barrelFileName: "generated-icons-barrel",
  svgoConfig: {
    plugins: [
      'cleanupAttrs'
    ],
  },
  compileSources: false,
};

module.exports = svgToTsConfig;

Configure svg-to-ts over package.json

To configure svg-to-ts over package.json you can simply add a svg-to-ts key in your package.json and use the config options. Once you run svg-to-ts those configurations will be picked up. The config object can eiter be an object or an array containing multiple configurations.

{
  "name": "my-icon-library",
  "version": "3.4.0",
  "scripts": {
    "generate-icons": "svg-to-ts"
  },
  "svg-to-ts": {
    "conversionType": "constants",
    "srcFiles": ["./projects/dinosaur-icons/icons/**/*.svg"],
    "outputDirectory": "./projects/dinosaur-icons/icons",
    "interfaceName": "DinosaurIcon",
    "typeName": "dinosaurIcon",
    "prefix": "dinosaurIcon",
    "svgoConfig": {
      "plugins": ["cleanupAttrs"]
    },
    "fileName": "dinosaur-icon.model",
    "additionalModelFile": "./projects/dinosaur-icons/src/lib",
    "compileSources": true
  }
}

Configure svg-to-ts over .rc file

To configure svg-to-ts over a .rc file you can add a .svg-to-tsrc file in the root of your project and use the config options. The configuration can either be written in JSON or YAML. It can eiter be an object for a single configuration or an array containing multiple configurations. Once you run svg-to-ts those configurations will be picked up.

{
  "conversionType": "constants",
  "srcFiles": ["./projects/dinosaur-icons/icons/**/*.svg"],
  "outputDirectory": "./projects/dinosaur-icons/icons",
  "interfaceName": "DinosaurIcon",
  "typeName": "dinosaurIcon",
  "prefix": "dinosaurIcon",
  "fileName": "dinosaur-icon.model",
  "svgoConfig": {
    "plugins": ["cleanupAttrs"]
  },
  "additionalModelFile": "./projects/dinosaur-icons/src/lib",
  "compileSources": true
}

If you decide to configure svg-to-ts by using a .rc file, it still makes sense to add the generate-icons script to your package.json

{
  "name": "my-icon-library",
  "version": "3.4.0",
  "scripts": {
    "generate-icons": "svg-to-ts"
  }
}

ConversionTypes

svg-to-ts offers three different kinds of conversion types; Converting your icons to a single object, converting your icons to constants or converting your icons to single files. Each approach is designed to solve a specific kind of problem. You can switch between approaches by passing conversionType property (object, constants or files).

1. Converting to a single object (conversionType==='object')

In this scenario the SVG icons are converted to a single object. It's an approach that is suitable if your icon registry accepts an object with the filename as key and the svg data as key.

Available options:

Example usage

Let's say we have the following four svg files in a inputfiles folder.

• expressionless.svg
• full.svg
• laughing.svg
• smiling-face.svg

We can now run svg-to-ts.ts --conversionType object -s ./inputfiles -o ./dist and we end up with the following file in our dist folder.

Sample output

export default {
  expressionLess: '<svg xmlns="http://ww...',
  full: '<svg xmlns="http://...',
  laughing: '<svg xmlns="http://ww...',
  smilingFace: '<svg xmlns="http://www....'
};

2. Multiple constants - Treeshakable and typesafe with one file (conversionType==='constants')

This approach converts your svg icons into multiple constants in the same file so that they can be used in combination with an icon registry. It furthermore also generates all necssary types. We wrote a step to step guide that explains this approach further and helps you create an icon library with this approach. Find out more in this blogpost

Only the icons included in the consuming SPA also end up in the final bundle of the SPA.

Available options:

Example usage

Let's say we have the following four svg files in a inputfiles folder.

• expressionless.svg
• full.svg
• laughing.svg
• smiling-face.svg

We can now run svg-to-ts.ts --conversionType constants -s ./inputfiles -o ./dist and we end up with the following file in our dist folder.

Sample ouput

export const myIconExpressionLess: MyIcon = {
  name: 'expression_less',
  data: `<svg xmlns="http://...`
};
export const myIconFull: MyIcon = {
  name: 'full',
  data: `<svg xmlns="http://www...`
};
export const myIconLaughing: MyIcon = {
  name: 'laughing',
  data: `<svg xmlns="http://www.w...`
};
export const myIconSmilingFace: MyIcon = {
  name: 'smiling_face',
  data: `<svg xmlns="http://www.w3...`
};
/* ⚠️ Do not edit this file - this file is generated by svg-to-ts*/

export type myIcons = 'expression_less' | 'full' | 'laughing' | 'smiling_face';
export interface MyIcon {
  name: myIcons;
  data: string;
}

3. Tree shakable and optimized for lazy loading (conversionType==='files')

This is the most sophisticated approach and also the approach that doesn't only support tree shaking but also supports code splitting which is especially usefull in scenarios where you are using lazy loading.

Here's a step by step guide on how to create an icon library that is optimized for tree shaking

Often, having the SVGs in a single file is enough. However, if you are in a more complex environment with bigger business applications, you may want to make the icons even more tree shakable.

In Angular, for example, having all icons in a single file shakes out the icons that are not used. However, icons always end up together in a chunk. The conversionOption = files allows you to configure svg-to-ts that icons are generated in a way that they can even be split to lazy loaded chunks. Means not only the amount of the icons in the chunk gets reduced, but also, where they end up. Means, an icon that is only used in a lazy loaded Angular feature module, will only end up there.

Available options:

Example usage

Let's say we have the following four svg files in a inputfiles folder.

• expressionless.svg
• full.svg
• laughing.svg
• smiling-face.svg

We can now run svg-to-ts.ts --conversionType files -s ./inputfiles -o ./dist and we end up with the following file in our dist folder.

Sample output

SVGO - SVG optimization

Under the hood we use the svgo project to optimize the svg icons. To configure SVGO you can add a svgo.config.js file to your root. Check out the official svgo page for further docs about the configuration.

Note: If you dont pass any options, svgo will apply some default options (more)

Starter project

If you want to build a standalone icon library we recommend you to checkout the svg-icon-lib-starter project on GitHub. This project allows you to build an astonishing framework-agnostic SVG icon library with ease. Out of the box icon optimization, build process, and icon showcase. 🚀

Angular builder

In case you are working with Angular and prefer the usage of a builder we recommend you to check out our offical Angular builder.

FAQ

Which approach should I use

This depends on your use case. If you have a simple application, it's probably enought to go with the single file or even a object. If you build a framework that is used by multiple teams, then you should probably go with the fully tree shakable scenario (generating multiple files).

Is it possilbe to create a standalone library?

Yes, it is. The current configurations also allow you to put your icon registry inside the component library and the icons in a dedicated npm package. This has the following advantages:

• Icons can be used with different registries
• Simplified build process
• Icons can be released independent of the component library
• No need to let svg-to-ts compile the icons - just set the compile flag to false.

Can I use the icons to generate a type?

If you have a method that decides which icon should be returned its useful to add a return type. To do so you can take advantage of the name subset helper generated by svg-to-ts. The name of the helper will be dynamically generated depending upon the value provided for the interfaceName property. An interfaceName of MyIcon will generate a helper called MyIconNameSubset as shown in the following example.

import {IconNameSubset, myIconSmile, myIconLaugh} from 'my-icon-lib';

type emojiIcons = MyIconNameSubset<[typeof myIconSmile, typeof myIconLaugh]>;

// resulting type is equal to type = 'smile' | 'laugh';

myMethod(): emojiIcons {
  // do stuff here
}

Contributors ✨

Thanks goes to these wonderful people (emoji key):

This project follows the all-contributors specification. Contributions of any kind welcome!