Develop and Test Changes Locally

Create the Source Control Repository

The repository is where Juan organizes the source files for the development project. Juan then creates a Salesforce DX project and adds it to the repo.

Name the repo something descriptive to reflect its purpose. Because this in an internal development project, Juan creates a private repository using Zephyrus’s enterprise account called language-courses.

Create a Salesforce DX Project

1. Open VS Code.
2. From the menu, select View | Command Palette.
3. In the command palette search box, enter sfdx project.
4. Select SFDX: Create Project with Manifest.
5. Use the same name as your GitHub repo, language-courses, then click Enter.
6. Click Create Project.

Add Project Files to the Repo in GitHub

1. In VS Code, open the DX project directory, then click the  Source Control icon.
2. Click Initialize Repository.
3. Hover over Changes, then click the + to stage all changes.
4. Accept the default branch in which to commit the repo, such as main.
5. Enter a commit message, then click the  Commit icon.
6. Click Publish Branch.
7. Confirm where you want to publish it.

Authorize and Log In to the Sandbox

Next, Ella authorizes (logs in) to her Developer sandbox using VS Code.

If you’re following along, use a Developer Edition org or Trailhead Playground. In step 3, select Project Default to use login.salesforce.com as the login URL.

1. From the command palette search box, enter sfdx authorize.
2. Select SFDX: Authorize an Org.
3. Select Sandbox for the login URL.
4. Enter an alias for the sandbox—for example, dev_sandbox.
5. Log in with the sandbox username and password.

Create the Custom Objects

Then, Ella creates the Language Course and Language Instructor custom objects in her Developer sandbox.

1. From Setup, click the Object Manager tab.
2. Click Create | Custom Object in the top-right corner.
3. For Label, enter Language Course Instructor. Notice that the Object Name and Record Name fields auto-fill.
4. For Plural Label, enter Language Course Instructors.
5. Check the box for Launch New Custom Tab Wizard, then click Save.
6. Select your desired tab style (Ella chooses Presenter), and click Next until you can save the object.

Pro tip: You can also use the schema generate commands to generate local source files for new custom objects, fields, tabs, and platform events. For this module we recommend you use Setup, but give the commands a try later on, we think you'll like them!

Define the Custom Field

Next, Ella defines the custom object field on the Language Course object that references the Language Course Instructor object.

If you’re following along, Ella created the Language Course object in a different module. This module assumes this object already exists in Ella’s Developer sandbox. Create this custom object before continuing:

1. From Setup, click the Object Manager tab.
2. Click Create | Custom Object in the top-right corner.
3. For Label, enter Language Course. Notice that the Object Name and Record Name fields auto-fill.
4. For Plural Label, enter Language Courses.
5. Check the box for Launch New Custom Tab Wizard, then click Save.
6. Select your desired tab style (Ella chooses Chalkboard) and click Next until you can save the object. 

1. From Setup, go to Object Manager | Language Course.
2. Click Fields & Relationships. Notice that some fields are already there, including a name field.
3. Click New.
4. For data type, select Master-Detail Relationship, then click Next.
5. From Related To, select Language Course Instructor, then click Next.
6. Fill out the following:
   • Field Label: Course Instructor
   • Description: Teacher for the language course
7. Click Next until you can save the field.

Track the Changes in a Change List

Ella creates a change list for the project to capture her changes.

Retrieve the Changes from the Developer Sandbox

Ella retrieves the changes from the sandbox to her local DX project. Because Ella tracks her changes along the way, she knows what to retrieve from her Developer sandbox.

Because Ella retrieves only a few components from her sandbox, she decides to use the Terminal in VS Code to run the Salesforce CLI project retrieve start command. Based on the default directory specified in the DX project, the CLI places the source in the force-app folder. Because you can’t add an empty folder in GitHub, Ella creates the force-app folder in the DX project on her local file system.

1. In the DX project on the local file system, create a force-app folder.
2. In the VS Code Terminal, run the CLI command to retrieve the new custom object and custom field:

   sf project retrieve start --metadata CustomObject:Language_Course_Instructor__c --metadata CustomField:Language_Course__c.Course_Instructor__c

   Ella uses --metadata instead of --source-dir because --source-dir can retrieve only files that already exist on the file system. The custom object appears in the force-app/main/default/objects directory. 

Commit the Changes to the Source Control Repository

Ella commits her changes to the repo, then creates a pull request to inform Juan that her changes are ready to review.

1. In VS Code, select the  Source Control icon.
2. Enter a commit comment, then click the  Commit icon.
3. Click Yes to add and commit the files.
4. From the VS Code command palette, select Git: Push To.
5. Select the origin repository.

Review the Code

If you’re following along, you can skip this section.

1. Create a pull request. In the GitHub repo, click Compare & pull request.
2. Assign reviewers. Ella assigns Juan to review and approve her changes.
3. Enter a comment for your reviewers.
4. Click Create pull request.

After Juan reviews and approves the code, Ella merges the pull request. Juan knows that he can begin his trigger work.

Deploy the Project Repo to the Developer Sandbox

First, Juan deploys Ella’s changes to his Developer sandbox so that both their environments are in sync.

If you’re following along, perform these steps in the folder you created for Juan’s development work, such as org-dev-juan. Use a new Developer Edition org or Trailhead playground for Juan’s Developer sandbox.

1. Clone the GitHub repo.
2. In VS Code, select Git: Create Branch, then provide a name for the branch. Juan names his branch juan_apex_trigger.
3. Select SFDX: Authorize an Org.
4. Select Sandbox for the login URL (test.salesforce.com).
5. Enter an alias for the sandbox—for example, dev_sandbox.
6. Log in with the sandbox username and password.
7. Deploy Ella’s changes to his developer sandbox. Right-click the objects folder, then select SFDX: Deploy Source to Org. Alternatively, Juan can run the Salesforce CLI command in the Terminal.

   sf project deploy start --metadata CustomObject:Language_Course_Instructor__c --metadata CustomField:Language_Course__c.Course_Instructor__c

Develop the Trigger

1. In the juan_apex_triggerbranch in VS Code, create the directory to put the trigger.
   1. Expand the force-app folder.
   2. Right click default, then select New Folder.
   3. Enter triggers.
2. Right-click the triggers folder, then click SFDX: Create Apex Trigger.
3. Enter LanguageCourseTriggerfor the trigger name. Enter the code for the trigger:

   trigger LanguageCourseTrigger on Language_Course__c (after insert, after update, after delete) {
   // <write your own notification code>
   }

4. Save the file.
5. Create a test for the trigger called TestLanguageCourseTrigger. As a seasoned developer, Juan makes sure that code coverage requirements are met.

Deploy the Changes to the Developer Sandbox

Juan deploys the trigger to validate and compile it, and then tests that it’s working correctly with the new object.

1. In the VS Code Terminal, right-click the triggers folder, then select SFDX: Deploy Source to Org. Alternatively, Juan can run the CLI command from the Terminal.

   sf project deploy start --source-dir force-app/main/default/triggers

   
2. Juan verifies that he captured all the changes and they work in the sandbox.
3. Juan adds his changes to the change list.

Commit the Changes to the Source Control Repository

Juan commits his changes to the repo, then creates a pull request. Ella performs the code review.

Plan the Next Release

Juan and Ella follow the same process for future customizations. If they develop customizations in VS Code, such as Juan’s trigger work, they deploy them to their Developer sandboxes for validation and testing.

They use Setup for everything else, so they can take advantage of builders and wizards and declarative interfaces. And then they retrieve those changes from the sandbox to their local file systems. They commit their changes to source control, create a pull request, and request a code review before merging their changes to the master branch.