- Create failing tests for `stateless` mode
- Implement `stateless` mode by turning of SSE in Streamable HTTP,
making the interaction a standard HTTP Req/Resp
Update send_notification method to properly construct JSON-RPC notification objects with jsonrpc version and method fields.
This ensures notifications conform to the JSON-RPC 2.0 specification when sent over HTTP transport.
https://www.jsonrpc.org/specification#notification
Another goal is to standardise the `send_notification` interface.
Before the revision, it was sufficient to pass the method and parameters in the case of stdio.
However, in the case of Streamable, a hash based on the JSON-RPC specification must be passed.
The reason for the change is that a NameError occurs when a POST request is made while the stream is closed because ModelContextProtocol is undefined.
I have also added test cases to check the behaviour when IOError and Errno::EPIPE occurs.
This PR suppresses the following backtrace of `Interrupt` (Ctrl+c) exception for stdio server:
## Before
```console
$ ./examples/stdio_server.rb
^C/Users/koic/src/github.com/modelcontextprotocol/ruby-sdk/lib/mcp/server/transports/stdio_transport.rb:20:
in 'IO#gets': Interrupt
from /Users/koic/src/github.com/modelcontextprotocol/ruby-sdk/lib/mcp/server/transports/stdio_transport.rb:20:
in 'MCP::Server::Transports::StdioTransport#open'
from ./examples/stdio_server.rb:95:in '<main>'
$ echo $?
130
```
## After
```console
$ ./examples/stdio_server.rb
^C
Exiting...
$ echo $?
130
```
This change should prevent unexpected backtrace from appearing when running the example:
https://github.com/modelcontextprotocol/ruby-sdk?tab=readme-ov-file#stdio-transport
Follow-up to #27.
This PR fixes the following build error:
```console
$ bundle exec rake
/Users/koic/.rbenv/versions/3.5-dev/lib/ruby/3.5.0+1/bundled_gems.rb:59:in 'Kernel.require': cannot load such file -- mcp/transports/stdio (LoadError)
Did you mean? mcp/transports/stdio_transport_test
from /Users/koic/.rbenv/versions/3.5-dev/lib/ruby/3.5.0+1/bundled_gems.rb:59:in 'block (2 levels) in Kernel#replace_require'
from /Users/koic/src/github.com/modelcontextprotocol/ruby-sdk/test/mcp/transports/stdio_transport_test.rb:4:in '<top (required)>'
from /Users/koic/.rbenv/versions/3.5-dev/lib/ruby/3.5.0+1/bundled_gems.rb:59:in 'Kernel.require'
from /Users/koic/.rbenv/versions/3.5-dev/lib/ruby/3.5.0+1/bundled_gems.rb:59:in 'block (2 levels) in Kernel#replace_require'
from /Users/koic/.rbenv/versions/3.5-dev/lib/ruby/gems/3.5.0+1/gems/rake-13.3.0/lib/rake/rake_test_loader.rb:21:in 'block in <main>'
from /Users/koic/.rbenv/versions/3.5-dev/lib/ruby/gems/3.5.0+1/gems/rake-13.3.0/lib/rake/rake_test_loader.rb:6:in 'Array#select'
from /Users/koic/.rbenv/versions/3.5-dev/lib/ruby/gems/3.5.0+1/gems/rake-13.3.0/lib/rake/rake_test_loader.rb:6:in '<main>'
rake aborted!
Command failed with status (1)
/Users/koic/.rbenv/versions/3.5-dev/bin/bundle:25:in 'Kernel#load'
/Users/koic/.rbenv/versions/3.5-dev/bin/bundle:25:in '<main>'
Tasks: TOP => default => test
(See full trace by running task with --trace)
```
https://github.com/modelcontextprotocol/ruby-sdk/actions/runs/15428236624/job/43420346011
The following is stated in #27.
> Breaking Changes
> `MCP::Transports::StdioTransport` is now `MCP::Server::Transports::StdioTransport`
What is shown here is the new name `MCP::Server::Transports::StdioTransport`, not `MCP::Server::Transports::Stdio`.
Therefore, the file path has been updated from `lib/mcp/server/transports/stdio.rb` to `lib/mcp/server/transports/stdio_transport.rb` to
match the module name. If `MCP::Server::Transports::Stdio` is preferred instead, please let me know and I will open a separate PR.
