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Sample

ecto 3.14.1: Validate a plain map with Ecto.Changeset alone: an embedded_schema, no Repo, no database and no ecto_sql

Verified sample for hex ecto 3.14.1: Validate a plain map with Ecto.Changeset alone: an embedded_schema, no Repo, no database and no ecto_sql. The contract…

sha256:ec1c423e61b01693526ccce5e694e6c68ed968878f00b8331b3d82c953abea87

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 1 linux x64 elixir 1 elixir mix

Verification-run environments

Environment Contract Stages Run
elixir 1 · linux alpine/x64 · docker ed25519:a2ec939a4c60e243 PASS compile:PASS · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · hex@1
2026-08-14
elixir 1 · linux alpine/x64 · docker ed25519:d91480838ac982c9 PASS compile:PASS · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · hex@1
2026-08-18

Case

HOW
Goal
Validate a plain map with Ecto.Changeset alone: an embedded_schema, no Repo, no database and no ecto_sql
Packages
Symbols
  • Ecto.Schema.embedded_schema
  • Ecto.Changeset.cast
  • Ecto.Changeset.validate_required
  • Ecto.Changeset.validate_number
  • Ecto.Changeset.validate_format
  • Ecto.Changeset.validate_length
  • Ecto.Changeset.empty_values
  • Ecto.Changeset.field_missing?
  • Ecto.Changeset.apply_action
  • Ecto.Changeset.apply_changes
  • Ecto.Changeset.traverse_errors
  • Ecto.Changeset.put_change
  • Ecto.Changeset.force_change
  • Ecto.InvalidChangesetError
Environment
elixir 1
Created
2026-08-14T14:09:57Z

Contract

  1. assert Ecto.Changeset validates with :ecto alone: ecto_sql is not installed and Ecto.Adapters.SQL will not load, while the embedded_schema reports no source table and no prefix where an otherwise identical schema/2 block reports its table name
  2. assert embedded_schema's own default primary key is an autogenerated binary_id that nothing outside a Repo insert ever fills in, so it stays nil, which is why the schema turns it off
  3. assert cast/4 keeps only the permitted fields and silently drops the rest, adding no error for a real-but-unpermitted field or for a key that is not a field at all, while changeset.params still holds the raw attempt and permitting that same field would have accepted it with no error either
  4. assert permitting a field the schema does not have raises ArgumentError, so a typo in the permitted list fails loudly while an unexpected param never does
  5. assert cast substitutes the field's default for an empty or whitespace-only string, so validate_required reports can't be blank, and that the substituted value is the declared default rather than nil, which silently resets a field that has one
  6. assert a value that survives the emptiness check is stored untrimmed, so only the check trims
  7. assert validate_required runs no blank check of its own and reuses changeset.empty_values, so casting with empty_values: [] lets an empty string pass validation while a validator that inspects the value still catches it
  8. assert passing a function in :empty_values now raises ArgumentError and the two-arity :trim_values option is the replacement
  9. assert validate_required decides presence with get_field, so a field carrying a non-nil schema default can never be reported missing, on a failing changeset or a passing one
  10. assert a type failure from cast is reported as is invalid with validation: :cast, leaves the field out of changes, and suppresses the later validators for that field
  11. assert apply_action/2 returns {:ok, struct} or {:error, changeset} with :action stamped onto the error changeset, apply_action!/2 raises Ecto.InvalidChangesetError, and apply_changes/1 returns the struct even when the changeset is invalid
  12. assert validate_number stores a %{number} placeholder plus interpolation metadata while validate_format's message is already complete, so a raw error message is not displayable
  13. assert traverse_errors interpolates and groups the repeated keys of changeset.errors into the field-to-list-of-messages map an API error body is built from, where a plain keyword lookup on changeset.errors returns only the most recent of a field's several errors
  14. assert put_change writes to changes regardless of the permitted list and regardless of the validators that already ran, is a no-op when the value equals the one on the data, and force_change/3 is the override

Files

  • csx.json
  • lib/csx_ecto/signup.ex
  • mix.exs
  • mix.lock
  • test/contract_test.exs
  • test/test_helper.exs

Download the source artifact (tar.gz)

Origin Seeder

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