Tempo.
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JSON encoding and decoding for the meta column of the
tempo_range and tempo_multirange composite types.
The range column of a composite carries the queryable span.
The meta column carries everything else Tempo knows that
tstzrange cannot express — qualifications, non-Gregorian
calendars, zone identifiers, recurrence rules, interval
metadata, and the implicit-vs-explicit-span distinction.
On store, the meta is a JSON document with this shape:
%{
"v" => 1,
"from" => iso8601_string | null,
"to" => iso8601_string | null,
"recurrence" => pos_integer | "infinity" | 1,
"direction" => 1 | -1,
"duration" => iso8601_string | null,
"repeat_rule" => iso8601_string | null,
"metadata" => map # must be JSON-serialisable
}On load, the endpoints are reconstituted via
Tempo.from_iso8601/1, which faithfully recovers every
Tempo feature ISO 8601 / ISO 8601-2 / IXDTF can express.
Encoding uses Erlang's built-in :json module (OTP 27+);
the jsonb column type handles storage and indexing on the
Postgres side.
Summary
Functions
Decode a JSON string (or already-decoded map) back into a
Tempo.Interval.t/0.
Decode a nil-aware JSON binary. Returns the decoded term directly.
Decoder options for :json.decode/3 that map JSON null to nil.
Encode a Tempo.Interval.t/0 to a JSON string for storage
in a jsonb column.
Encode an arbitrary term as a nil-aware JSON binary.
Encoder callback for :json.encode/2 that treats nil as JSON null.
Functions
@spec decode_interval(String.t() | map()) :: {:ok, Tempo.Interval.t()} | {:error, term()}
Decode a JSON string (or already-decoded map) back into a
Tempo.Interval.t/0.
Returns {:ok, interval} or {:error, reason}.
Decode a nil-aware JSON binary. Returns the decoded term directly.
Decoder options for :json.decode/3 that map JSON null to nil.
@spec encode_interval(Tempo.Interval.t()) :: iodata()
Encode a Tempo.Interval.t/0 to a JSON string for storage
in a jsonb column.
Returns an iolist suitable for handing to Postgrex.
Encode an arbitrary term as a nil-aware JSON binary.
Encoder callback for :json.encode/2 that treats nil as JSON null.