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Sample

ecto 3.14.1: Navigate default foreign key types in Ecto associations and handle :id type defaults when schemas use binary_id primary keys

Verified sample for hex ecto 3.14.1: Navigate default foreign key types in Ecto associations and handle :id type defaults when schemas use binary_id primary…

sha256:e447eb9ad840ecdae7ce357052059a87dbbe2a677cede495fd997434da32bf90

This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured. How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people. MIT-0

Execution evidence

The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.

Evidence basis
Signed contract pass
Verification receipts
2
Signing keys that built it
2
Declared environment elixir linux x64 elixir elixir mix

Verification-run environments

Environment Contract Stages Run
elixir 1 · linux alpine/x64 · docker ed25519:d91480838ac982c9 PASS compile:PASS · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · hex@1
2026-08-17
elixir 1 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 PASS compile:PASS · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · hex@1
2026-08-18

Case

HOW
Goal
Navigate default foreign key types in Ecto associations and handle :id type defaults when schemas use binary_id primary keys
Packages
Symbols
  • Ecto.Schema.belongs_to
  • Ecto.Schema.has_many
  • Ecto.Schema.has_one
  • Ecto.Schema
  • Ecto.Changeset.cast
Environment
elixir
Created
2026-08-17T04:43:50Z

Contract

  1. assert belongs_to defaults the foreign key field type to :id integer even when @primary_key is configured as :binary_id, causing binary UUID string parameters to fail with a cast validation error
  2. assert casting integer values into default belongs_to foreign key fields succeeds because the unconfigured foreign key type defaults to :id
  3. assert configuring @foreign_key_type :binary_id sets the default association foreign key field type to :binary_id and allows valid UUID strings to cast successfully
  4. assert belongs_to defaults :foreign_key to the association name with an _id suffix and :references to :id
  5. assert belongs_to with define_field: false constructs the association reflection but omits the foreign key from schema fields
  6. assert has_many and has_one default :foreign_key to the snake_cased source module name with an _id suffix and :references to :id

Files

  • NOTES.md
  • csx.json
  • mix.exs
  • mix.lock
  • test/contract.exs
  • test/test_helper.exs

Download the source artifact (tar.gz)

Origin Seeder

csx-seed