Aries-staticagent

==========================

Highlights

- **Add return route support.**
- **Add mechanism for directly awaiting a message, bypassing regular dispatch.**
This makes it possible to treat messages more like a return-response model and
significantly simplifies some flows.

Detailed Changes

General improvements

- Favor named arguments over keyword arguments where possible.

Examples

- Added a [return route server example](examples/return_route_server.py),
intended to be run with the corresponding client, to demonstrate return route
support.
- Added a [return route client example](examples/return_route_client.py),
intended to be run with the corresponding server, to demonstrate return route
support.
- Removed original `cron_returnroute` example.

Improvements to StaticConnection

- Add construct for conditionally awaiting a message on the connection,
bypassing regular dispatch. As a result, two new methods are defined on
`StaticConnection`: `await_message`, and `send_and_await_reply`. See [return
route client example](examples/return_route_client.py)
- Add Reply construct to support return routing while keeping transport
decoupled from the library. See [return route server
example](examples/return_route_server.py).
- Add `MessageUndeliverable` Exception, raised when no endpoint or return route
is currently available for the connection or other errors with the connection
are encountered.
- Add support for unpacking plaintext messages.
- Better error handling in `send`.

Improvements to Dispatcher

- Add `remove_handler` method.

==========================

Highlights

- **Switch to PyNacl instead of PySodium.** PyNacl includes pre-built binary
packages of `libsodium`; this switch means removing the dependency of
`libsodium` being installed on the system.
- **`Module` and route definition rewrite.** The Module system has been
significantly improved, allowing for cleaner and more flexible module
definitions.

Detailed Changes

Improvements to Static (Agent) Connection

- Rename to `StaticConnection`.
- Reorder parameter into slightly more natural order. (Breaking change)
- Split out pack and unpack functionality into separate functions for a little
added flexibility and simpler testing.
- `route` and `route_module` no longer simply wrap a dispatcher method. These
methods are now responsible for creating Handlers corresponding to the route
or routes defined by a module. See below for more on Dispatcher and Handler
changes/additions.


Improvements to Crypto

- Switch to PyNacl instead of PySodium.
- Add field signing and verification helpers.


Improvements to Module

Overhauled route definitions (breaking changes):
- Use `route` to define a route (instead of `route_def`).
- No implicit routes. If a method of a module does not have a route decorator,
it will never be routed to.
- A bare `route` will create a handler for the message type defined by
combining the module's `DOC_URI`, `PROTOCOL`, `VERSION` and the method's name.
Use `route(name='...')` to specify a name that differs from the method name.
- Route a message that normally doesn't match the module's `DOC_URI`,
`PROTOCOL`, or `VERSION` with `route(doc_uri='...', protocol='...',
version='...')`. If any of these keyword arguments are not specified, the
module's defaults are used. You can also include name, as in the previous
example, to specify a name that differs from the method name.
- `route('<raw_type_string>')` will also work.


Improvements to Dispatcher

- Altered Dispatcher to operate on "Handlers" rather than simple type routes and
modules. This improves handler selection and provides an overall cleaner
interface.


Added Handler

- Relatively simple container used to help map a Type to a handler function.


Added Type

- Object used for representing the type string.
- Allows for comparing types, better version information.
- Reduced code duplication across Message, Module, and Dispatcher.


Examples

- Cleaned up all examples.
- Added example for using a Module and web server.

==========================

This update includes many backported updates from the Aries Protocol Test Suite
"agent core" which was originally derived from this library.

Potentially Breaking Changes
----------------------------
- Messages with malformed message types will raise an `InvalidMessage` exception
instead of `InvalidMessageType`.
- `Semver` class moved from `module` to `utils`.

Additions
---------
- Added `route_module()` to `StaticAgentConnection`.
- Added `clear_routes()` and `clear_modules()` to `StaticAgentConnection`.
- `StaticAgentConnection.__init__()` can now take the raw bytes of keys as well
as base58 strings.
- [Message Trust Contexts](aries_staticagent/mtc.py);
`StaticAgentConnection.handle()` will add contexts as appropriate. See [the
tests](tests/test_mtc.py) for examples of querying or adding to these
contexts.
- More tests