## Highlights

### A Major Rework of Handlers

https://github.com/cablehead/xs/wiki/Handlers

- Prior to this release, handlers had virtually no error handling. Now, when an
  error occurs, handlers will unregister themselves and record the error in the
  unregister frame's metadata.
- The handlers closure shape is now `{|frame, state| ... }`, meaning the frame
  is passed as an argument instead of being supplied as `$in`.
- Treatment of return values has been normalized: there is no longer any
  difference between handler return values for stateful and stateless handlers.
  By default, non-empty return values are appended as <handler>.out (previously
  it was just <handler>).
- You can configure the return value suffix and TTL using the return_options in
  the metadata of the handler registration frame.
- `.append` calls from a handler are now batched and processed together *after*
  the handler successfully completes. They aren't yet emitted in a fjall atomic
  batch but will be in the future. handler_id, frame_id, and state_id (if there
  is state) are not automatically included in the metadata of these appended
  frames.
- Stateful handlers now communicate state updates by appending a
  <handler>.state frame.
- A useful technique is to set the return value suffix to `.state`: then your
  return value will become the next state value for the subsequent handler
  call.

### Miscellaneous

- You can now import from one store into another:
  https://github.com/cablehead/xs/wiki/Export-and-Import
- The CLI client can now access stores behind HTTPS and BasicAuth
- Two new TTL options for frames:
    - `time:<milliseconds>`: the frame will exist for the specified number of
      milliseconds
    - `head:<count>`: keeps the most recent `count` frames for a given topic;
      among other uses, this is useful for using `xs` as a KV store

## Breaking Changes

- See handlers notes above
- fjall dependency has been upgraded from 1.5 to 2.4
- $env.XSPWD has been renamed to $env.XS_ADDR
- `xs pipe` has been renamed to `xs process` -- .pipe -> .process


## Raw commit messages:

- 4d983f3 docs: add --locked to the cargo install instructions 🙏 @fdncred
- 2d840a8 rename $env.XSPWD to $env.XS_ADDR
- e02edab feat: add a version endpoint; bump version in toml to 0.1.0
- 96c482b feat: add conveniences to dump and load a store
- a190163 feat: add frame import endpoint for backup/restore operations
- 6b5b51f feat: add xs cas-post: which inserts content into the CAS without needing to insert a corresponding frame
- ca9b5bf s/postfix/suffix/g -- 🙏 @marvin_j97
- 1fa2678 feat: lots and lots of work on handlers (#28)
- 0c9e689 tuning: use less (lsm) threads (#27)
- ecf1e2e fix: update the example handlers to take frame as an argument
- 5ab960b fix(handlers): ignore unregistered handlers on startup
- 5f07a3a feat(handlers): validate closure shape and emit .unregister on registration error
- f4f01f3 refactor: rename HandlerMeta to Meta, reuse Handler for /process endpoint
- c5a0390 refactor: rename pipe to process
- ee6193c refactor(handlers): pass frame/state as args instead of pipeline, encapsulate eval
- ea648e9 refactor(handlers): split handlers.rs into module with handler and serve
- 5907db4 fix: only include expose in xs.start meta when expose option is set
- abe717f fix: pull TTL into its own module: bring nu/commands/append_command.rs up to date with TTL changes (#26)
- cf30c8d feat(store): add Head TTL to retain latest N frames per topic (#24)
- cbf70a8 fix: topic index encoding (#25)
- 02938f6 feat: support unregister for handlers
- d1106ae fix: avoid sending any events generated as a response to a handler, back to that handler
- 71b3c83 fix: 's/eval_block/eval_block_with_early_return/g'
- f7d367b feat: flesh out support for TTL::Time(Duration)
- 5d1f2d0 feat: bump fjall dependency from 1.5 to 2.4 🎉
- 9af2792 fix: .pipe now uses eval_block_with_early_return
- 82edbf3 fix: iterate on error handling / messages when using the cli to call the API
- 674181d image: add deno2
- aa02716 example(discord-bot): add README note for slash command handler
- ed4a5ee example(discord-bot): add an example /dice slash command handler
- 48776da example(discord-bot): bump API version to v10
- 4e9b2c7 Update README.md
- dd00b68 Update README.md
- ff3a931 example(discord-bot): read access token from the stream
- ceace87 chore: iterate on the packaged container image
- 6d2d558 chore: iterate on the packaged container image
- 6b74142 feat: client support for stores behind https and basicauth (#22)
- 76e37d1 release: allow --expose to be enabled in the container image
- 84921cf release: allow --expose to be enabled in the container image
- f170252 fix(example/solid-ui): actually push up store/cas.ts