Store school email domains

[PetarSimonovic]

Status

Closes #1325

What's changed?

• Add a school_email_domains table
• Add a SchoolEmailDomain model
• Add a SchoolEmailDomainValidator that normalises and checks domains
• Update association on School
• Add valid_domain? method on School
• Add and update specs

[Copilot]

Pull request overview

Introduces first-class storage for school email domains by adding a dedicated table/model and wiring it into the School domain model, with accompanying specs.

Changes:

• Added school_email_domains table with a composite unique index per school.
• Added SchoolEmailDomain model with before_validation normalization (strip leading @, downcase).
• Updated School to has_many :school_email_domains and added/updated model specs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
spec/models/school_spec.rb	Adds association + dependent-destroy coverage for school_email_domains.
spec/models/school_email_domain_spec.rb	Adds model spec coverage for domain normalization behavior.
db/schema.rb	Reflects new school_email_domains table and foreign key.
db/migrate/20260420104937_create_school_email_domains.rb	Creates the new school_email_domains table and composite unique index.
app/models/school_email_domain.rb	Introduces the new model and domain normalization callback.
app/models/school.rb	Adds has_many :school_email_domains, dependent: :destroy.

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[github-actions]

Test coverage

91.13% line coverage reported by SimpleCov.
Run: https://github.com/RaspberryPiFoundation/editor-api/actions/runs/26042630378

[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

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[fspeirs]

Overall this looks like the right approach. I have one consideration about validating domains - I feel like it would be helpful to be stricter in checking that the user hasn't typo'ed their domain or misunderstood what we are asking for.

[fspeirs]

Directionally, quite correct. Just some sharpening of the normalisation approach in school_email_domain and a request for a testing method in school.rb. The lack of a testing method is non-blocking if it's coming in a separate PR.

[peconia]

The regex we use in profile side to validate is '^\\s*(?:[A-Za-z0-9](?:[A-Za-z0-9-]{0,61}[A-Za-z0-9])?\\.)+[A-Za-z]{2,63}\\s*$'

While it is similar, we would reject things that had a dash in the wrong place, like example.-wrong.edu, but that would be approved by this one. I also wonder about things that are domains but not email domains, like having www. or ftp. prefix to the domain. Maybe that will come down to making sure the UI is clear in what is expected, and the API level can validate some things too.

[zetter-rpf]

Nice one