💡Please note, that we have released an updated plugin migration guide. We suggest following the migration guide in the Strapi documentation.

Strapi v4 is here! This is a major release packing a lot of amazing new features. Unfortunately, this does mean that there will be some breaking changes when moving from v3 to v4. Since the new Plugin API is a big part of Strapi v4, we decided to put together a migration guide for plugin developers.

Here you will find all the steps you need to take to migrate your plugin with as little friction as possible. To expedite the process we've also included some codemods, or code that modifies your code automatically.

The goal of this guide is to get a v3 plugin up and running on v4 as fast as possible by resolving breaking changes. It is not an exhaustive resource for the v4 plugin API. For more information, you should consult the v4 plugin API documentation: Server API, Admin API

When possible, this guide suggests the use of codemods. To use the codemods you will need to clone this repository and run all commands provided from its root:

git clone https://github.com/strapi/codemods.git

1. Enable your plugin

A v3 plugin was enabled if it was installed or it was found in the plugins directory. In v4, if a plugin is installed (in the package.json dependencies), it is automatically enabled. However, while developing a local plugin you must explicitly enable the plugin in the ./config/plugins.js file of the Strapi application. Disabling any plugin and adding additional config can be done here as well. Here's an example for a local plugin:

module.exports = ({ env }) => ({
  "my-plugin": {
    enabled: true,
    resolve: "./my-local-plugin",
    config: {
      // additional config goes here
    },
  },
});

2. Update the folder structure

As opposed to v3 plugins, which required a specific folder structure, v4 plugins are developed using a programmatic API.

At the root of your plugin you must have the strapi-server.js and strapi-admin.js entry files. Otherwise, the folder structure is up to you. Here is an example:

/plugin
-- /admin
---- /components
---- /pages
---- // etc...
---- index.js
-- /server
---- /config
---- /controllers
---- /routes
---- bootstrap.js
---- // etc...
---- index.js
-- strapi-server.js // require('./server')
-- strapi-admin.js // require('./admin')

Migrate with codemod

To make this update, you can use the following codemod to move files and folders into a v4 plugin structure:

node ./migration-helpers/update-plugin-folder-structure.js <path-to-v3-plugin> [path-for-v4-plugin]

ℹ️ This codemod will create a new v4 plugin leaving your v3 plugin in place. We recommend confirming the v4 version of your plugin is working properly before deleting the v3 version.

The codemod creates the two entry files strapi-server.js and strapi-admin.js, organizes files and folders into /server and /admin directories respectively, changes models to contentTypes , and exports services as functions.

ℹ️ For a more detailed explanation of what the codemod does, consult the check list below

Migrate by hand

If you prefer to make these changes yourself, you can use the checklist below to help migrate your plugin.

💡 This is only a suggested folder structure. You can organize the plugin however you want as long as everything is imported to strapi-admin.js and strapi-server.js

• Create a server directory

Controllers, services, and middlewares

• Move controllers, services , and middlewares to /server . For each directory add an index.js file that exports all files in that folder. Make sure that each file in these directories exports a function taking {strapi} as a parameter and returns an object. For example the controllers directory would look like this:

// server/controllers/my-controllerA

module.exports = ({ strapi }) => ({
  doSomething(ctx) {
    ctx.body = { message: "HelloWorld" };
  },
});

// server/controllers/index.js

"use strict";

const myControllerA = require("./my-controllerA");
const myControllerB = require("./my-controllerB");

module.exports = {
  myControllerA,
  myControllerB,
};

Bootstrap Function

• Move bootstrap from /server/config/functions/bootstrap.js to /server/bootstrap.js and pass {strapi} as an argument:

// server/bootstrap.js
"use strict";

module.exports = ({ strapi }) => ({
  // bootstrap!
});

Routes

• Move routes from /config/routes.json to /server/routes/index.json. Your routes should return an array or an object specifying admin or content-api routes.
• Make sure your routes handler matches the same casing of your controller exports

// server/controllers/index.js

"use strict";

const myControllerA = require("./my-controllerA");
const myControllerB = require("./my-controllerB");

module.exports = {
  myControllerA,
  myControllerB,
};

// server/routes/index.js

module.exports = [
  {
    method: "GET",
    path: "/my-controller-a/",
    // Camel case handler to match export in server/controllers/index.js
    handler: "myControllerA.index",
    config: { policies: [] },
  },
];

Policies

• Move policies from /config/policies to /server/policies/<policyName>.js, add an index.js file to the directory that exports all files in the folder.

Models / Content-Types

• Move / rename the models directory to /server/content-types

  • Move / rename each model's <modelName>.settings.json to /server/content-types/<contentTypeName>/schema.json

    • Update the info object on each schema.json

    "info": {
      "singularName": "content-type-name", // kebab-case required
      "pluralName": "content-type-names", // kebab-case required
      "displayName": "Content-Type Name",
      "name": "Content-Type Name",
    };

    • If your model used lifecycle-hooks found in <model-name>.js move / rename this file /server/content-types/<contentTypeName>/lifecycle.js, otherwise delete the file.
    • Create an index file for each Content Type that exports the schema and lifecycles

    // server/content-types/<content-type-name>/index.js
    
    const schema = require("./schema.json");
    const lifecycles = require("./lifecycles.js");
    
    module.exports = {
      schema,
      lifecycles,
    };

    • Create an index file for server/content-types and export all content-types
    • Make sure the key for your Content-Types matches the singular name on the Content-Type’s schema.json info object.

    // server/content-types/content-type-a/schema.json
    
    "info": {
      "singularName": "content-type-a", // kebab-case required
      "pluralName": "content-type-as", // kebab-case required
      "displayName": "Content-Type A",
      "name": "Content-Type A",
    };

    // server/content-types/index.js
    "use strict";
    
    const contentTypeA = require("./content-type-a");
    const contentTypeB = require("./content-type-b");
    
    module.exports = {
      "content-type-a": contentTypeA,
      "content-type-b": contentTypeB,
    };

Entry Files

• Create the server entry file at the root of your plugin: strapi-server.js and require all necessary files for your plugin. For example:

// strapi-server.js
"use strict";

const bootstrap = require("./server/bootstrap");
const contentTypes = require("./server/contentTypes");
const controllers = require("./server/contentTypes");
const services = require("./server/services");
const routes = require("./server/routes");

module.exports = {
  bootstrap,
  contentTypes,
  controllers,
  services,
  routes,
};

• Create the frontend entry file at the root of your project: strapi-admin.js For example:

// strapi-admin.js
"use strict";

module.exports = require("./admin/src").default;

3. Migrate the Back End

Update imports

Strapi has now moved to scoped imports. All Strapi imports will need to be updated from strapi-package-name to @strapi/package-name.

Migrate with codemod

To update your package.json you can use the following codemod:

node ./migration-helpers/update-package-dependencies.js <path-to-plugin>

⚠️ This will modify your plugin source code. Before running this command, be sure you have initialized a git repo, the working tree is clean, you've pushed your v3 plugin, and you are on a new branch.

To update any files importing Strapi packages you can run:

npx jscodeshift -t ./transforms/update-scoped-imports.js <path-to-file | path-to-folder>

⚠️ This will modify your plugin source code. Before running this command, be sure you have initialized a git repo, the working tree is clean, you've pushed your plugin to GitHub, and you are on a new branch.

Migrate by hand

If you prefer to make this change yourself, you just need to find any imports of Strapi packages and rename them to @strapi/package-name

Update Models to Content-Types

Update Getters

If your plugin has models (contentTypes) you will need to make the following changes.

Models are now called ContentTypes. All getters like strapi.models will need to be updated to strapi.contentTypes

Migrate with codemod

You can use the following codemod to replace all instances of strapi.models with strapi.contentTypes

npx jscodeshift -t ./transforms/change-model-getters-to-content-types.js <path-to-file | path-to-folder>

⚠️ This will modify your plugin source code. Before running this command, be sure you have initialized a git repo, the working tree is clean, you've pushed your plugin to GitHub, and you are on a new branch.

Migrate by hand

If you prefer to do this yourself, you just need to replace any instance of .models with .contentTypes

💡 To refactor further, check out the new getters introduced in the Strapi v4 Plugin API

Update relations

If your plugin has contentTypes with relations, those attributes will have to be updated manually depending on the relation. Here's an example of all possible relations between an article and an author

// article attributes
"articleHasOneAuthor": {
  "type": "relation",
  "relation": "oneToOne",
  "target": "api::author.author"
},
"articleHasAndBelongsToOneAuthor": {
  "type": "relation",
  "relation": "oneToOne",
  "target": "api::author.author",
  "inversedBy": "article"
},
"articleBelongsToManyAuthors": {
  "type": "relation",
  "relation": "oneToMany",
  "target": "api::author.author",
  "mappedBy": "article"
},
"authorHasManyArticles": {
  "type": "relation",
  "relation": "manyToOne",
  "target": "api::author.author",
  "inversedBy": "articles"
},
"articlesHasAndBelongsToManyAuthors": {
  "type": "relation",
  "relation": "manyToMany",
  "target": "api::author.author",
  "inversedBy": "articles"
},
"articleHasManyAuthors": {
  "type": "relation",
  "relation": "oneToMany",
  "target": "api::author.author"
}

// author attributes
"article": {
  "type": "relation",
  "relation": "manyToOne",
  "target": "api::article.article",
  "inversedBy": "articleBelongsToManyAuthors"
},
"articles": {
  "type": "relation",
  "relation": "manyToMany",
  "target": "api::article.article",
  "inversedBy": "articlesHasAndBelongsToManyAuthors"
}

Update configuration

If you have any default configuration it should be exported as an object on the config property. This object expects a default property storing the default plugin configuration, and a validator function that takes the config as an argument. For example:

// strapi-server.js

module.exports = () => {
// ...bootstrap, routes, controllers, etc...
config: {
    default: { optionA: true },
    validator: (config) => {
      if (typeof config.optionA !== 'boolean') {
        throw new Error('optionA has to be a boolean');
      }
    },
  },
}

4. Migrate the Front End

Register the plugin

A v3 plugin exports its configurations as an object passed to registerPlugin(config), like this:

export default (strapi) => {
  const pluginDescription =
    pluginPkg.strapi.description || pluginPkg.description;
  const icon = pluginPkg.strapi.icon;
  const name = pluginPkg.strapi.name;
  const plugin = {
    blockerComponent: null,
    blockerComponentProps: {},
    description: pluginDescription,
    icon,
    id: pluginId,
    initializer: Initializer,
    injectedComponents: [],
    isReady: false,
    isRequired: pluginPkg.strapi.required || false,
    layout: null,
    lifecycles,
    mainComponent: App,
    name,
    pluginLogo,
    preventComponentRendering: false,
    reducers,
    trads,
    menu: {
      pluginsSectionLinks: [
        {
          destination: `/plugins/${pluginId}`,
          icon,
          label: {
            id: `${pluginId}.plugin.name`,
            defaultMessage: "My Plugin",
          },
          name,
          permissions: pluginPermissions.main,
        },
      ],
    },
  };

  return strapi.registerPlugin(plugin);
};

To migrate this to v4 we will need to export a function that calls the register() lifecycle function, passing the current strapi app as an argument:

export default {
  register(app) {
    // executes as soon as the plugin is loaded
  },
};

Here we can go ahead and register our plugin by grabbing the name and id keys from the old configuration object:

import pluginId from './pluginId';

const pluginDescription = pluginPkg.strapi.description || pluginPkg.description;
const name = pluginPkg.strapi.name;

export default {
  register(app) {
      app.registerPlugin({
        id: pluginId
        name,
      })
    }
  }

Add Menu Link

To add a link to your plugin in the Strapi Admin, use the addMenuLink() function called in the register lifecycle. The menu key from the v3 config object can be passed to app.addMenuLink() with the following properties changed:

• destination ⇒ to
• label ⇒ intlLabel
• icon is no longer a string, it's now a React component. You can create it in a separate file like this:

import React from "react";
import { Icon } from "@strapi/parts/Icon";
import { FontAwesomeIcon } from "@fortawesome/react-fontawesome";

const PluginIcon = () => (
  <Icon as={() => <FontAwesomeIcon icon="paint-brush" />} width="16px" />
);

export default PluginIcon;

In v3 the component would be specified on the mainComponent key, in v4 the component is passed as a dynamic import to the app.addMenuLink() function.

import pluginId from './pluginId';
import pluginPermissions from './permissions';
import PluginIcon from './PluginIcon'

const pluginDescription = pluginPkg.strapi.description || pluginPkg.description;
const name = pluginPkg.strapi.name;

export default {
  register(app) {
    app.addMenuLink({
      to: `/plugins/${pluginId}`,
      icon: PluginIcon,
      intlLabel: {
        id: `${pluginId}.plugin.name`,
        defaultMessage: 'My Plugin',
      },
      permissions: pluginPermissions.main,
      Component: async () => {
        const component = await import(/* webpackChunkName: "my-plugin-page" */ './pages/PluginPage');

        return component;
      },
    });

    app.registerPlugin({
      description: pluginDescription,
      icon,
      id: pluginId
      name
    });
  }
}

Going Further

All available actions

At this point a basic plugin with a single view should be migrated to v4. However, it is likely that you will want to customize your plugin further. Depending on the needs of your plugin you will have to look into the different API's available.

In addition to the register() lifecycle function, which is executed as soon as the plugin is loaded, there is also the bootstrap() lifecycle function which executes after all plugins are loaded.

To add a settings link or section, use redux reducers, hook into other plugins, and modify the UI with injection zones, consult this table for all available API's and their associated lifecycle functions.

Register Translations

The plugin interface can also export an asynchronous registerTrads() function for registering translation files. You can use the following function:

import { prefixPluginTranslations } from "@strapi/helper-plugin";

export default {
  register(app) {
    // register code...
  },
  bootstrap(app) {
    // bootstrap code...
  },
  async registerTrads({ locales }) {
    const importedTrads = await Promise.all(
      locales.map((locale) => {
        return import(
          /* webpackChunkName: "[pluginId]-[request]" */ `./translations/${locale}.json`
        )
          .then(({ default: data }) => {
            return {
              data: prefixPluginTranslations(data, pluginId),
              locale,
            };
          })
          .catch(() => {
            return {
              data: {},
              locale,
            };
          });
      })
    );

    return Promise.resolve(importedTrads);
  },
};

Conclusion

Hopefully this guide has helped you migrate your plugin from Strapi v3 to Strapi v4. Strapi Market is coming soon and we are looking forward to many plugins developed by the community. For more information about Strapi Market, read the blog post. If you are ready to submit your plugin all you need to do is fill out this form.

If you have any issues with the codemods or would like to contribute to the project please create an issue or open a pull request.