SDK-5434: Update docs

docs/acp/user/develop-an-app/develop-an-app.md

@@ -11,35 +11,35 @@ This document will walk you through the process of developing an app using Spryk
 
 {% info_block infoBox "Development guidelines" %}
 
-Development guidelines for ACP apps contains general rules how to design an app and write code for it.
-ACP apps are based on the [mini-framework](https://github.com/spryker-projects/mini-framework), which is its turn is based on the Spryker Framework. Therefore, we recommend following the same rules that are applicable for the [Spryker project development](https://docs.spryker.com/docs/scos/dev/guidelines/project-development-guidelines.html#updating-spryker).
+Development guidelines for ACP apps contain general rules on how to design an app and write code for it.
+ACP apps are based on the [mini-framework](https://github.com/spryker-projects/mini-framework), which in its turn is based on the Spryker Framework. Therefore, we recommend following the same rules that are applicable for the [Spryker project development](https://docs.spryker.com/docs/scos/dev/guidelines/project-development-guidelines.html#updating-spryker).
 
 {% endinfo_block %}
 
 ## Prerequisites
 
-Before you begin, ensure that you have the following prerequisites in place:
+Before you begin, make sure that the following prerequisites are met:
 
-- Completed the [thought process](#thought-process) for your app.
-- An empty GitHub repository.
-- A local project directory for your app (for example, `/www/my-app`).
-- [DockerSDK](https://github.com/spryker/docker-sdk) installed globally.
+- You have completed the [thought process](#thought-process) for your app.
+- There is an empty GitHub repository.
+- There is a local project directory for your app (for example, `/www/my-app`).
+- [DockerSDK](https://github.com/spryker/docker-sdk) is installed globally.
 
 Make sure you have the Spryker Docker SDK, Git, and an empty repository for your app code.
 
 {% info_block infoBox "Info" %}
 
-[Download](https://github.com/spryker-projects/mini-framework) the completed example from the Mini-Framework.
+[Download](https://github.com/spryker-projects/mini-framework/tree/examples/acp/create-an-app-final) the completed example from the Mini-Framework.
 
 {% endinfo_block %}
 
-## Thought process
-First, think about what your app should be capable of: what features it will bring and what data will be exchanged, not only to you but also to those interested in your app functionality. For example, what messages could be of interest to others, and what API endpoints you should provide. 
+## 1. Thought process
+First, think about what your app should be capable of: what features it will bring and what data will be exchanged, not only to you but also to those interested in your app functionality. For example, what messages could be of interest to others and what API endpoints you should provide. 
 
 ### API-first
 It's strongly recommended that apps follow the API-first approach. 
-API-first means that your app is centered on the API. It should be possible to perform every action via the scripting language, and every piece of functionality should be available for other systems to leverage. For more information on the API-first approach, see [this blog post](https://www.algolia.com/blog/product/the-5-principles-of-api-first-development-and-what-does-api-first-even-mean/).
-You need to have a clear understanding of what your app API will provide to others, and always keep that in mind when designing your app.
+API-first means that your app is centered around the API. It should be possible to perform every action via the scripting language, and every piece of functionality should be available for other systems to leverage. For more information on the API-first approach, see [this blog post](https://www.algolia.com/blog/product/the-5-principles-of-api-first-development-and-what-does-api-first-even-mean/).
+You need to have a clear understanding of what your app API will provide to others and always keep that in mind when designing your app.
 
 ### Schema-first
 
@@ -57,7 +57,7 @@ You can use the following tools to design your APIs:
 - [Async API Studio](https://studio.asyncapi.com/)
 - [Swagger Editor](https://editor.swagger.io/)
 
-## Create an app
+## 2. Create an app
 
 To create an app, execute the following commands:
 
@@ -69,9 +69,9 @@ git add --all
 git commit -m "first commit"
 ```
 
-After running these commands, you will have a new local repository that needs to be linked with your remote one.
+After running these commands, you get a new local repository that needs to be linked with your remote one.
 
-If not done yet, create a new remote repository by opening your [Github account](https://github.com/newConnect). After you created a new repository, GitHub shows you instructions on how to continue. Follow the list below, as you don’t need some of the first steps proposed by GitHub since you’ve already initialized Git and you already have the `README.md` file from the cloned repository.
+If not done yet, create a new remote repository by opening your [Github account](https://github.com/newConnect). After you have created the new repository, GitHub will display instructions on how to proceed. Execute the commands from the list below, as you don’t need some of the first steps proposed by GitHub since you’ve already initialized Git and you already have the `README.md` file from the cloned repository.
 
 ```bash
 git branch -M main
@@ -84,38 +84,53 @@ You can also execute this step later.
 
 {% endinfo_block %}
 
-Now, you have done the groundwork that enables you to develop an App. You created a new repository that contains the boilerplate code for almost any App you’d like to build.
+Now, you have done the groundwork that enables you to develop an app. You created a new repository that contains the boilerplate code for almost any app you’d like to build.
 
-## Start the local development environment
+### Validation
 
-The Mini-Framework already comes with the predefined Docker configuration. Change the `deploy.dev.yml` by replacing `glue-backend.de.spryker.local` with `my-app.de.spryker.local`. After that, run the command provided in the next section at the root of your new repository.
+Make sure that the project is cloned properly and has no uncommitted files.
 
-### Boot and up your environment
 
-Execute the following command to boot your application and start it:
+## 3. Start the local development environment
+
+To start the local development environment, you need must boot and up your environment. Do the following:
+
+1. Clone Spryker Docker SDK to the project directory:
+
+```bash
+git clone git@github.com:spryker/docker-sdk.git docker
+```
+
+2. Execute the following command to boot your application and start it:
 
 ```bash
 docker/sdk boot deploy.dev.yml
 docker/sdk up
 ```
 
+3. Validate if everything is set up correctly. Do the following:
+
+- Make sure that all the commands are executed without errors and the tests are successfully passed.
+- Check that docker containers are started by executing the `docker/sdk ps` command.
+- Make sure that `my-app.spryker.local` domain is resolved by executing the `ping my-app.spryker.local` command.
+
 After creating the development environment, you have several ways of using the app. The easiest one is to run the test suite as follows:
 
 ```bash
 docker/sdk testing codecept run
 ```
 
-You will now see that your app boilerplate code is up and running.
+Now, your app boilerplate code should be up and running.
 
-## Add the app manifest files
+## 4. Add the app manifest files
 
 Before your app can be listed in the App Store Catalog, you need to add the following files.
 
 ### Manifest
 
 The manifest file is the most important one for the app. It contains data that will be displayed in the App Store Catalog. You can use the [manifest code snippet](/docs/acp/user/develop-an-app/code-snippets/manifest-json-file.html) and update it to your needs. Add the manifest file to `config/app/manifest/en_US.json` of your app.
 
-Manifest files must have the local name as the filename, for example, `en_US.json`, and should be placed inside the `config/app/manifest` directory.
+Manifest files must have the locale name as the filename, for example, `en_US.json`, and should be placed inside the `config/app/manifest` directory.
 
 ### Configuration
 
@@ -125,7 +140,11 @@ The configuration file contains all necessary form fields for inputs required by
 
 The translation file contains all translations for the form fields you’ve previously defined. You can use the Hello World [example translation file](/docs/acp/user/develop-an-app/code-snippets/translation-json-file.html) and update it to your needs. Add this file to `config/app/translation.json` of your app.
 
-## Add the registry (code)
+### Validation
+
+Make sure that all the needed configuration files have been created and populated properly.
+
+## 5. Add the registry (code)
 
 Every app requires default endpoints for the App Registry Service. This service acts as an intermediary between the App Store Catalog and all apps. Each app is registered in the App Registry Service and requires the following endpoints for communication:
 
@@ -135,38 +154,42 @@ Every app requires default endpoints for the App Registry Service. This service
 The `spryker/app-kernel` module transforms the Mini-Framework into an app. It provides SyncAPI schema and code for configuration and disconnection, as well as an AsyncAPI schema and code for the AppConfigure and AppDisconnect messages. 
 The `spryker/message-broker-aws` module installs the necessary plugins for sending and receiving messages. 
 
-## Build the transfer objects
+### Validation
+
+After the next two steps, check the new routes in [Test the endpoints](#test-the-endpoints).
+
+## 6. Build the transfer objects
 
 Transfer objects are used in many places. Since you installed some modules, you also need to generate the transfers. To generate the transfers, run the following command:
 
 ```bash
 docker/sdk cli console transfer:generate
 ```
 
-## Update the database
+## 7. Update the database
 
 Generate the database entities and update the database:
 
 ```bash
 docker/sdk cli console propel:install
 ```
 
-## Test the endpoints
+## 8. Test the endpoints
 
 You can now test the `configure` request with the following snippets. Run the cURL snippets from your host machine.
 
 ### Test the /private/configure endpoint
 
 Follow the guidelines in [Test the endpoints](/docs/acp/user/connect-an-app.html#test-the-endpoints).
 
-## Implement business logic
+## 9. Implement business logic
 
 Your app is now ready to use, although it doesn't contain any business logic yet. 
 Start implementing the business logic by implementing a synchronous or asynchronous API.
 
-## Debug your app
+## 10. Debug your app
 
-If you want to understand what is happening in the code, you can [debug your app](/docs/acp/user/develop-an-app/debug-an-app-with-xdebug.html) with XDebug and by adding `--cookie "XDEBUG_SESSION=PHPSTORM;path=/;" \` to the above cURL request.
+If you want to understand what is happening in the code, you can [debug your app](/docs/acp/user/develop-an-app/debug-an-app-with-xdebug.html) with XDebug and by adding `--cookie "XDEBUG_SESSION=PHPSTORM;" \` to the above cURL request.
 
 Entry points for setting breakpoints are the following:
 - `Spryker\Glue\App\Controller\AppConfigController`