DrinkMeAlice.Ash.Codec (drink_me_alice v0.1.0)

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Attribute ↔ SurrealDB value mapping for the Ash data layer, keyed on Ash.Type.storage_type/2.

storage typeSurreal fieldwritten as
:string :citext :uuid :binary_idstringexact string (DrinkMeAlice.exact_string/1)
:naive_datetime* :date :time*stringexact ISO-8601 string
:integerint$p (i64)
:booleanbool$p
:utc_datetime :utc_datetime_usecdatetime<datetime>$p
:decimaldecimal<decimal>$p (decimal string)
:floatfloat<float>$p (float string)
:mapstringexact canonical JSON text
{:array, scalar}array<T>element-wise as above

Why: SurrealDB 3.0.5 coerces typed-looking JSON strings — date-shaped strings become datetimes and do not survive a <string> cast (see DrinkMeAlice.exact_string/1) — so every string travels in the exact form. The outbound encoder (DrinkMeAlice.Json.encode/1) carries only canonical terms, so floats, decimals and datetimes travel as strings cast in SurrealQL. Maps are stored as canonical JSON text rather than as objects: an object's nested strings would be coerced, and there is no server-side JSON parse to undo it; the cost is that map contents are not filterable. nil is written as the literal NONE: a JSON null is rejected by option<T> fields.

Anything else is {:error, {:unsupported_type, name, storage}} — at schema generation and at write time — rather than a lossy guess.

Summary

Types

kind()

Functions

decode(attr, value)

Decode one stored field value back into the attribute's Ash value (nil for an absent field).

encode(attr, value)

Encode one attribute value for a write or a filter comparison: {:ok, :none} for nil (write the literal NONE), or {:ok, {kind, wire_value}} — pair with param_sql/2.

field_type(attr)

The Surreal field type for an attribute, without option<>: {:ok, "string"} | {:error, {:unsupported_type, name, storage}}.

param_sql(arg1, name)

The SurrealQL expression reading param name of kind back into the stored value.

storage(map)

The storage type for an attribute.

wire_kind(storage)

The wire kind for a storage type, or :error.

Types

kind()

@type kind() :: :str | :plain | {:cast, binary()} | :json | {:array, kind()}

Functions

decode(attr, value)

@spec decode(map(), term()) :: {:ok, term()} | {:error, term()}

Decode one stored field value back into the attribute's Ash value (nil for an absent field).

encode(attr, value)

@spec encode(map(), term()) :: {:ok, :none | {kind(), term()}} | {:error, term()}

Encode one attribute value for a write or a filter comparison: {:ok, :none} for nil (write the literal NONE), or {:ok, {kind, wire_value}} — pair with param_sql/2.

field_type(attr)

@spec field_type(map()) :: {:ok, binary()} | {:error, term()}

The Surreal field type for an attribute, without option<>: {:ok, "string"} | {:error, {:unsupported_type, name, storage}}.

param_sql(arg1, name)

@spec param_sql(kind(), binary()) :: binary()

The SurrealQL expression reading param name of kind back into the stored value.

storage(map)

The storage type for an attribute.

wire_kind(storage)

@spec wire_kind(term()) :: {:ok, kind()} | :error

The wire kind for a storage type, or :error.