feat: implement custom emails models

[ngovinh2k2]

What?

Implement the custom emails models

Why?

How?

Testing?

• Functional Testing
• Security
• Performance
• Error Handling
• Code Quality
• Documentation
• Database
• Deployment
• Final Review

Anything Else?

[gemini-code-assist]

Code Review

This pull request introduces a new custom_email application to allow organizations to customize their email configurations, including sender details, theme colors, and header images. It integrates these custom emails into the organization settings and provides a migration to backfill existing organizations with default email configurations. The review feedback highlights several important improvements: avoiding the import of application services within migrations to prevent future schema mismatch failures, using models.EmailField instead of models.CharField for email validation, and safely accessing Django settings with getattr to avoid potential runtime errors in environments where specific settings might be missing.

Important

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For more details on the timeline and next steps, please review the Help Documentation.

[gemini-code-assist]

Importing helper functions or models from application code (like apps.custom_email.service) inside Django migrations is a known anti-pattern. If the models or services change in the future, running this migration from scratch will fail because the historical database schema won't match the current codebase. Instead, define the default email data directly within the migration file or in a static constants file that does not import any Django models.

def get_default_emails():
    common_data = {
        "sender_name": "The @SpaceDF team",
        "sender_email": "support@spacedf.com",
        "footer_text": "©2025 Digital Fortress. All rights reserved.",
        "header_image": "",
        "show_logo": True,
        "social_links": {
            "linkedin_url": "https://vn.linkedin.com/company/digital-fortress-vn",
            "facebook_url": "https://www.facebook.com/digitalfortress.dev/",
            "tiktok_url": "",
            "instagram_url": "https://www.instagram.com/df.iot/",
        },
        "metadata": {
            "show_facebook": True,
            "show_instagram": True,
            "show_linkedin": True,
            "show_tiktok": False,
        },
    }
    return [
        {
            **common_data,
            "email_type": "invitation_to_space",
            "theme_colors": {
                "background_color": "#FFFFFF",
                "primary_color": "#171A28",
            },
        },
        {
            **common_data,
            "email_type": "verification_code",
            "theme_colors": {
                "background_color": "#FFFFFF",
                "primary_color": "#171A28",
            },
        },
        {
            **common_data,
            "email_type": "reset_password",
            "theme_colors": {
                "background_color": "#FFFFFF",
                "primary_color": "#171A28",
            },
        },
    ]


def backfill_organization_emails(apps, schema_editor):
    Organization = apps.get_model("organization", "Organization")
    OrganizationEmail = apps.get_model("custom_email", "OrganizationEmail")

    existing_pairs = set(
        OrganizationEmail.objects.values_list("organization_id", "email_type")
    )
    emails_to_create = []
    default_emails = get_default_emails()

    for organization in Organization.objects.all().iterator():
        for email_data in default_emails:
            email_type = email_data["email_type"]
            if (organization.id, email_type) in existing_pairs:
                continue

            emails_to_create.append(
                OrganizationEmail(
                    organization_id=organization.id,
                    **email_data,
                )
            )

    if emails_to_create:
        OrganizationEmail.objects.bulk_create(emails_to_create, batch_size=100)

[gemini-code-assist]

Using models.EmailField instead of models.CharField for email addresses is a standard Django best practice. It automatically validates that the input is a valid email address at both the model and form/serializer levels.

Suggested change

	sender_email = models.CharField(max_length=255, blank=True)
	sender_email = models.EmailField(max_length=255, blank=True)

[gemini-code-assist]

To match the model definition change of sender_email to EmailField, update the field type in the initial migration as well.

Suggested change

	("sender_email", models.CharField(blank=True, max_length=255)),
	("sender_email", models.EmailField(blank=True, max_length=255)),

[gemini-code-assist]

Accessing settings.AWS_S3 and settings.HOST directly can lead to AttributeError or other runtime crashes if these settings are not defined or are set to None in certain environments (e.g., local development or testing). Use getattr with a safe fallback to make this code more robust.

Suggested change

	if instance.header_image:
	data["url_header_image"] = get_presigned_url(
	settings.AWS_S3.get("AWS_STORAGE_BUCKET_NAME"),
	f"uploads/{instance.header_image}",
	)
	return data
	image_mapping = {
	EmailTypes.INVITATION_TO_SPACE: "auth/invitation.png",
	EmailTypes.VERIFICATION_CODE: "auth/verification_code.png",
	EmailTypes.RESET_PASSWORD: "auth/forget_password.png",
	}
	image_path = image_mapping.get(instance.email_type, "")
	host = settings.HOST.rstrip("/")
	data["url_header_image"] = (
	f"{host}/static/images/{image_path}" if image_path else ""
	)
	return data
	if instance.header_image:
	aws_s3 = getattr(settings, "AWS_S3", {}) or {}
	data["url_header_image"] = get_presigned_url(
	aws_s3.get("AWS_STORAGE_BUCKET_NAME"),
	f"uploads/{instance.header_image}",
	)
	return data
	image_mapping = {
	EmailTypes.INVITATION_TO_SPACE: "auth/invitation.png",
	EmailTypes.VERIFICATION_CODE: "auth/verification_code.png",
	EmailTypes.RESET_PASSWORD: "auth/forget_password.png",
	}
	image_path = image_mapping.get(instance.email_type, "")
	host = getattr(settings, "HOST", "") or ""
	host = host.rstrip("/")
	data["url_header_image"] = (
	f"{host}/static/images/{image_path}" if image_path and host else ""
	)
	return data