Codec: Fix EventId, Require timestamp (#84)

CHANGELOG.md

@@ -9,10 +9,18 @@ The `Unreleased` section name is replaced by the expected version of next releas
 ## [Unreleased]
 
 ### Added
+
+- `Core.EventData/TimelineEvent`: Exposed default ctors [#83](https:/jet/FsCodec/pull/83)
+
 ### Changed
+
+- `Codec.Create`: Made timestamp mandatory in low level `up` / `down` signature [#83](https:/jet/FsCodec/pull/83)
+
 ### Removed
 ### Fixed
 
+- `EventData.Create`: restored defaulting of `EventId` to `Guid.NewGuid` broken in [#82](https:/jet/FsCodec/pull/82) [#83](https:/jet/FsCodec/pull/83)
+
 <a name="3.0.0-rc.6"></a>
 ## [3.0.0-rc.6] - 2022-09-02
 

src/FsCodec.Box/Codec.fs

@@ -1,4 +1,4 @@
-// Equivalent of FsCodec.NewtonsoftJson/SystemTextJson.Codec intended to provide equivalent calls and functionality, without actually serializing/deserializing as JSON
+// Mirror of FsCodec.NewtonsoftJson/SystemTextJson.Codec intended to provide equivalent calls and functionality, without actually serializing/deserializing as JSON
 // This is a useful facility for in-memory stores such as Equinox's MemoryStore as it enables you to
 // - efficiently test behaviors from an event sourced decision processing perspective (e.g. with Property Based Tests)
 // - without paying a serialization cost and/or having to deal with sanitization of generated data in order to make it roundtrippable through same
@@ -27,7 +27,7 @@ type Codec private () =
  // <summary>Maps a fresh Event resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c><br/>
  // The function is also expected to derive an optional <c>meta</c> object that will be serialized with the same <c>encoder</c>,
  // and <c>eventId</c>, <c>correlationId</c>, <c>causationId</c> and an Event Creation<c>timestamp</c></summary>.
- down : struct ('Context * 'Event) -> struct ('Contract * 'Meta voption * Guid * string * string * DateTimeOffset voption),
+ down : struct ('Context * 'Event) -> struct ('Contract * 'Meta voption * Guid * string * string * DateTimeOffset),
  // <summary>Enables one to fail encoder generation if union contains nullary cases. Defaults to <c>false</c>, i.e. permitting them.</summary>
  [<Optional; DefaultParameterValue(null)>] ?rejectNullaryCases)
  : FsCodec.IEventCodec<'Event, obj, 'Context> =
@@ -45,7 +45,7 @@ type Codec private () =
  // <summary>Maps a fresh Event resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c>
  // The function is also expected to derive
  // a <c>meta</c> object that will be serialized with the same options (if it's not <c>None</c>)
- // and an Event Creation <c>timestamp</c>.</summary>
+ // and an Event Creation <c>timestamp</c> (Default: DateTimeOffset.UtcNow).</summary>
  down : 'Event -> struct ('Contract * 'Meta voption * DateTimeOffset voption),
  // <summary>Uses the 'Context passed to the Encode call and the 'Meta emitted by <c>down</c> to a) the final metadata b) the <c>eventId</c> c) the <c>correlationId</c> and d) the <c>causationId</c></summary>
  mapCausation : struct ('Context * 'Meta voption) -> struct ('Meta voption * Guid * string * string),
@@ -66,7 +66,7 @@ type Codec private () =
  // <summary>Maps a fresh <c>'Event</c> resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c>
  // The function is also expected to derive
  // a <c>meta</c> object that will be serialized with the same options (if it's not <c>None</c>)
- // and an Event Creation <c>timestamp</c>.</summary>
+ // and an Event Creation <c>timestamp</c> (Default: DateTimeOffset.UtcNow).</summary>
  down : 'Event -> struct ('Contract * 'Meta voption * DateTimeOffset voption),
  // <summary>Enables one to fail encoder generation if union contains nullary cases. Defaults to <c>false</c>, i.e. permitting them.</summary>
  [<Optional; DefaultParameterValue(null)>] ?rejectNullaryCases)

src/FsCodec.Box/CoreCodec.fs

@@ -22,7 +22,7 @@ type Codec private () =
  // <summary>Maps a fresh Event resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c><br/>
  // The function is also expected to derive an optional <c>meta</c> object that will be serialized with the same <c>encoder</c>,
  // and <c>eventId</c>, <c>correlationId</c>, <c>causationId</c> and an Event Creation<c>timestamp</c></summary>.
- down : struct ('Context * 'Event) -> struct ('Contract * 'Meta voption * Guid * string * string * DateTimeOffset voption),
+ down : struct ('Context * 'Event) -> struct ('Contract * 'Meta voption * Guid * string * string * DateTimeOffset),
  // <summary>Enables one to fail encoder generation if union contains nullary cases. Defaults to <c>false</c>, i.e. permitting them.</summary>
  [<Optional; DefaultParameterValue(null)>] ?rejectNullaryCases)
  : FsCodec.IEventCodec<'Event, 'Body, 'Context> =
@@ -36,12 +36,12 @@ type Codec private () =
  allowNullaryCases = not (defaultArg rejectNullaryCases false))
 
  { new FsCodec.IEventCodec<'Event, 'Body, 'Context> with
+
  member _.Encode(context, event) =
- let struct (c, meta : 'Meta voption, eventId, correlationId, causationId, timestamp : DateTimeOffset voption) = down struct (context, event)
+ let struct (c, meta : 'Meta voption, eventId, correlationId, causationId, timestamp) = down (context, event)
  let enc = dataCodec.Encode c
- let meta' = match meta with ValueSome x -> encoder.Encode<'Meta> x | ValueNone -> Unchecked.defaultof<_>
- let ts = match timestamp with ValueNone -> None | ValueSome v -> Some v
- EventData.Create(enc.CaseName, enc.Payload, meta', eventId, correlationId, causationId, ?timestamp = ts)
+ let meta' = match meta with ValueSome x -> encoder.Encode<'Meta> x | ValueNone -> Unchecked.defaultof<'Body>
+ EventData(enc.CaseName, enc.Payload, meta', eventId, correlationId, causationId, timestamp)
 
  member _.TryDecode encoded =
  match dataCodec.TryDecode { CaseName = encoded.EventType; Payload = encoded.Data } with
@@ -61,9 +61,9 @@ type Codec private () =
  // <summary>Maps a fresh Event resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c>
  // The function is also expected to derive
  // a <c>meta</c> object that will be serialized with the same options (if it's not <c>None</c>)
- // and an Event Creation <c>timestamp</c>.</summary>
+ // and an Event Creation <c>timestamp</c> (Default: DateTimeOffset.UtcNow).</summary>
  down : 'Event -> struct ('Contract * 'Meta voption * DateTimeOffset voption),
- // <summary>Uses the 'Context passed to the Encode call and the 'Meta emitted by <c>down</c> to a) the final metadata b) the <c>eventId</c> c) the <c>correlationId</c> and d) the <c>causationId</c></summary>
+ // <summary>Uses the 'Context passed to the Encode call and the 'Meta emitted by <c>down</c> to produce a) the final metadata b) the <c>eventId</c> c) the <c>correlationId</c> and d) the <c>causationId</c></summary>
  mapCausation : struct ('Context * 'Meta voption) -> struct ('Meta voption * Guid * string * string),
  // <summary>Enables one to fail encoder generation if union contains nullary cases. Defaults to <c>false</c>, i.e. permitting them.</summary>
  [<Optional; DefaultParameterValue(null)>] ?rejectNullaryCases)
@@ -72,7 +72,7 @@ type Codec private () =
  let down struct (context, union) =
  let struct (c, m, t) = down union
  let struct (m', eventId, correlationId, causationId) = mapCausation (context, m)
- struct (c, m', eventId, correlationId, causationId, t)
+ struct (c, m', eventId, correlationId, causationId, match t with ValueSome t -> t | ValueNone -> DateTimeOffset.Now)
  Codec.Create(encoder, up = up, down = down, ?rejectNullaryCases = rejectNullaryCases)
 
  /// <summary>Generate an <code>IEventCodec</code> using the supplied <c>encoder</c>.<br/>
@@ -88,7 +88,7 @@ type Codec private () =
  // <summary>Maps a fresh <c>'Event</c> resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c>
  // The function is also expected to derive
  // a <c>meta</c> object that will be serialized with the same options (if it's not <c>None</c>)
- // and an Event Creation <c>timestamp</c>.</summary>
+ // and an Event Creation <c>timestamp</c> (Default: DateTimeOffset.UtcNow).</summary>
  down : 'Event -> struct ('Contract * 'Meta voption * DateTimeOffset voption),
  // <summary>Enables one to fail encoder generation if union contains nullary cases. Defaults to <c>false</c>, i.e. permitting them.</summary>
  [<Optional; DefaultParameterValue(null)>] ?rejectNullaryCases)
@@ -107,5 +107,5 @@ type Codec private () =
  : FsCodec.IEventCodec<'Union, 'Body, unit> =
 
  let up struct (_e : FsCodec.ITimelineEvent<'Body>, u : 'Union) : 'Union = u
- let down (event : 'Union) = struct (event, ValueNone, ValueNone)
+ let down (event : 'Union) = struct (event, ValueNone (*Meta*), ValueNone (*Timestamp*))
  Codec.Create(encoder, up = up, down = down, ?rejectNullaryCases = rejectNullaryCases)

src/FsCodec.NewtonsoftJson/Codec.fs

@@ -74,7 +74,7 @@ type Codec private () =
  // <summary>Maps a fresh Event resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c><br/>
  // The function is also expected to derive an optional <c>meta</c> object that will be serialized with the same <c>encoder</c>,
  // and <c>eventId</c>, <c>correlationId</c>, <c>causationId</c> and an Event Creation<c>timestamp</c></summary>.
- down : struct ('Context * 'Event) -> struct ('Contract * 'Meta voption * Guid * string * string * DateTimeOffset voption),
+ down : struct ('Context * 'Event) -> struct ('Contract * 'Meta voption * Guid * string * string * DateTimeOffset),
  // <summary>Configuration to be used by the underlying <c>Newtonsoft.Json</c> Serializer when encoding/decoding. Defaults to same as <c>Options.Default</c></summary>
  [<Optional; DefaultParameterValue(null)>] ?options,
  // <summary>Enables one to fail encoder generation if union contains nullary cases. Defaults to <c>false</c>, i.e. permitting them.</summary>
@@ -94,7 +94,7 @@ type Codec private () =
  // <summary>Maps a fresh Event resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c>
  // The function is also expected to derive
  // a <c>meta</c> object that will be serialized with the same options (if it's not <c>None</c>)
- // and an Event Creation <c>timestamp</c>.</summary>
+ // and an Event Creation <c>timestamp</c> (Default: DateTimeOffset.UtcNow).</summary>
  down : 'Event -> struct ('Contract * 'Meta voption * DateTimeOffset voption),
  // <summary>Uses the 'Context passed to the Encode call and the 'Meta emitted by <c>down</c> to a) the final metadata b) the <c>eventId</c> c) the <c>correlationId</c> and d) the <c>causationId</c></summary>
  mapCausation : struct ('Context * 'Meta voption) -> struct ('Meta voption * Guid * string * string),

src/FsCodec.SystemTextJson/Codec.fs

@@ -44,7 +44,7 @@ type Codec private () =
  // <summary>Maps a fresh Event resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c><br/>
  // The function is also expected to derive an optional <c>meta</c> object that will be serialized with the same <c>encoder</c>,
  // and <c>eventId</c>, <c>correlationId</c>, <c>causationId</c> and an Event Creation<c>timestamp</c></summary>.
- down : struct ('Context * 'Event) -> struct ('Contract * 'Meta voption * Guid * string * string * DateTimeOffset voption),
+ down : struct ('Context * 'Event) -> struct ('Contract * 'Meta voption * Guid * string * string * DateTimeOffset),
  // <summary>Configuration to be used by the underlying <c>System.Text.Json</c> Serializer when encoding/decoding. Defaults to same as <c>Options.Default</c></summary>
  [<Optional; DefaultParameterValue(null)>] ?options,
  // <summary>Enables one to fail encoder generation if union contains nullary cases. Defaults to <c>false</c>, i.e. permitting them.</summary>
@@ -64,7 +64,7 @@ type Codec private () =
  // <summary>Maps a fresh Event resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c>
  // The function is also expected to derive
  // a <c>meta</c> object that will be serialized with the same options (if it's not <c>None</c>)
- // and an Event Creation <c>timestamp</c>.</summary>
+ // and an Event Creation <c>timestamp</c> (Default: DateTimeOffset.UtcNow).</summary>
  down : 'Event -> struct ('Contract * 'Meta voption * DateTimeOffset voption),
  // <summary>Uses the 'Context passed to the Encode call and the 'Meta emitted by <c>down</c> to a) the final metadata b) the <c>eventId</c> c) the <c>correlationId</c> and d) the <c>causationId</c></summary>
  mapCausation : struct ('Context * 'Meta voption) -> struct ('Meta voption * Guid * string * string),

src/FsCodec.SystemTextJson/CodecJsonElement.fs

@@ -43,7 +43,7 @@ type CodecJsonElement private () =
  // <summary>Maps a fresh Event resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c><br/>
  // The function is also expected to derive an optional <c>meta</c> object that will be serialized with the same <c>encoder</c>,
  // and <c>eventId</c>, <c>correlationId</c>, <c>causationId</c> and an Event Creation<c>timestamp</c></summary>.
- down : struct ('Context * 'Event) -> struct ('Contract * 'Meta voption * Guid * string * string * DateTimeOffset voption),
+ down : struct ('Context * 'Event) -> struct ('Contract * 'Meta voption * Guid * string * string * DateTimeOffset),
  // <summary>Configuration to be used by the underlying <c>System.Text.Json</c> Serializer when encoding/decoding. Defaults to same as <c>Options.Default</c></summary>
  [<Optional; DefaultParameterValue(null)>] ?options,
  // <summary>Enables one to fail encoder generation if union contains nullary cases. Defaults to <c>false</c>, i.e. permitting them.</summary>
@@ -63,7 +63,7 @@ type CodecJsonElement private () =
  // <summary>Maps a fresh Event resulting from a Decision in the Domain representation type down to the TypeShape <c>UnionConverter</c> <c>'Contract</c>
  // The function is also expected to derive
  // a <c>meta</c> object that will be serialized with the same options (if it's not <c>None</c>)
- // and an Event Creation <c>timestamp</c>.</summary>
+ // and an Event Creation <c>timestamp</c> (Default: DateTimeOffset.UtcNow).</summary>
  down : 'Event -> struct ('Contract * 'Meta voption * DateTimeOffset voption),
  // <summary>Uses the 'Context passed to the Encode call and the 'Meta emitted by <c>down</c> to a) the final metadata b) the <c>eventId</c> c) the <c>correlationId</c> and d) the <c>causationId</c></summary>
  mapCausation : struct ('Context * 'Meta voption) -> struct ('Meta voption * Guid * string * string),