a284bf7314
## Motivation and Context
The MCP specification (SEP-2243) requires the Streamable HTTP transport to mirror
selected JSON-RPC body fields into HTTP headers so that intermediaries such as load balancers,
gateways, and observability tooling can route and inspect requests without parsing the body.
`Mcp-Method` carries the JSON-RPC `method` and is required on all requests and notifications,
while `Mcp-Name` carries `params.name` (`tools/call`, `prompts/get`) or `params.uri` (`resources/read`).
The Ruby SDK client did not send these headers, so servers enforcing SEP-2243 rejected
its requests with `400 Bad Request`, breaking interoperability. This aligns the Ruby SDK with
the TypeScript and Python SDKs, both of which send these headers from their Streamable HTTP clients.
Header values that cannot be transmitted safely as-is, such as non-ASCII text, control characters
(including CR/LF, which would otherwise allow header injection), or significant leading or
trailing whitespace, are wrapped per SEP-2243 as `=?base64?<base64>?=`. Safe ASCII values are sent unchanged.
The encoding uses `Array#pack("m0")` to avoid depending on the `base64` gem.
Resolves #366
## How Has This Been Tested?
Client tests cover deriving `Mcp-Name` from `params.name` (`tools/call`, `prompts/get`) and
falling back to `params.uri` (`resources/read`), both symbol- and string-keyed params,
requests and notifications without a name or uri sending only `Mcp-Method`, and non-Hash params sending
only `Mcp-Method`. Value encoding is covered for non-ASCII names, surrounding whitespace, CR/LF
(verifying no header injection), and values that already match the `=?base64?...?=` sentinel.
## Breaking Changes
None. The change is purely additive: existing requests now carry the required `Mcp-Method` and `Mcp-Name` headers
alongside the headers already sent. The `x-mcp-header` / `Mcp-Param-*` custom headers remain out of scope,
matching the current state of the TypeScript and Python SDKs.
1253 lines
38 KiB
Ruby
1253 lines
38 KiB
Ruby
# frozen_string_literal: true
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require "test_helper"
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require "event_stream_parser"
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require "faraday"
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require "webmock/minitest"
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require "mcp/client/http"
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require "mcp/client/tool"
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require "mcp/client"
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module MCP
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class Client
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class HTTPTest < Minitest::Test
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def test_raises_load_error_when_faraday_not_available
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client = HTTP.new(url: url)
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# simulate Faraday not being available
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HTTP.any_instance.stubs(:require).with("faraday").raises(LoadError, "cannot load such file -- faraday")
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error = assert_raises(LoadError) do
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# This should immediately try to instantiate the client and fail
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client.send_request(request: {})
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end
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assert_includes(error.message, "The 'faraday' gem is required to use the MCP client HTTP transport")
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assert_includes(error.message, "Add it to your Gemfile: gem 'faraday', '>= 2.0'")
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end
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def test_raises_load_error_when_event_stream_parser_not_available
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stub_request(:post, url)
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.to_return(
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status: 200,
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headers: { "Content-Type" => "text/event-stream" },
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body: "data: {}\n\n",
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)
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HTTP.any_instance.stubs(:require).with("faraday").returns(true)
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HTTP.any_instance.stubs(:require).with("event_stream_parser")
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.raises(LoadError, "cannot load such file -- event_stream_parser")
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error = assert_raises(LoadError) do
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client.send_request(request: { method: "tools/list" })
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end
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assert_includes(error.message, "The 'event_stream_parser' gem is required to parse SSE responses")
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assert_includes(error.message, "Add it to your Gemfile: gem 'event_stream_parser', '>= 1.0'")
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end
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def test_headers_are_added_to_the_request
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headers = { "Authorization" => "Bearer token" }
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client = HTTP.new(url: url, headers: headers)
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/list",
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}
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stub_request(:post, url)
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.with(
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headers: {
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"Authorization" => "Bearer token",
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"Content-Type" => "application/json",
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"Accept" => "application/json, text/event-stream",
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},
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body: request.to_json,
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)
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.to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: { tools: [] } }.to_json,
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)
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# The test passes if the request is made with the correct headers
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# If headers are wrong, the stub_request won't match and will raise
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client.send_request(request: request)
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end
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def test_accept_header_is_included_in_requests
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/list",
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}
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stub_request(:post, url)
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.with(
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headers: {
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"Accept" => "application/json, text/event-stream",
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},
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)
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.to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: { tools: [] } }.to_json,
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)
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client.send_request(request: request)
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end
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def test_custom_accept_header_overrides_default
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custom_accept = "application/json"
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custom_client = HTTP.new(url: url, headers: { "Accept" => custom_accept })
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/list",
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}
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stub_request(:post, url)
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.with(
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headers: {
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"Accept" => custom_accept,
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},
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)
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.to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: { tools: [] } }.to_json,
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)
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custom_client.send_request(request: request)
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end
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def test_mcp_method_and_name_headers_for_tools_call
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/call",
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params: { name: "get_weather", arguments: { city: "Tokyo" } },
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "tools/call", "Mcp-Name" => "get_weather" },
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).to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: {} }.to_json,
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)
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client.send_request(request: request)
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end
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def test_mcp_name_header_falls_back_to_uri_for_resources_read
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "resources/read",
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params: { uri: "file:///README.md" },
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "resources/read", "Mcp-Name" => "file:///README.md" },
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).to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: {} }.to_json,
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)
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client.send_request(request: request)
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end
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def test_mcp_method_and_name_headers_for_prompts_get
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "prompts/get",
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params: { name: "greeting" },
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "prompts/get", "Mcp-Name" => "greeting" },
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).to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: {} }.to_json,
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)
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client.send_request(request: request)
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end
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def test_mcp_method_header_without_name_when_params_lack_name_and_uri
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/list",
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "tools/list" },
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) do |req|
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!req.headers.key?("Mcp-Name")
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end.to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: { tools: [] } }.to_json,
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)
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client.send_request(request: request)
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end
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def test_mcp_name_header_is_base64_encoded_when_unsafe
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/call",
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params: { name: "café" },
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "tools/call", "Mcp-Name" => "=?base64?Y2Fmw6k=?=" },
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).to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: {} }.to_json,
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)
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client.send_request(request: request)
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end
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def test_mcp_method_header_for_notification_without_id
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request = {
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jsonrpc: "2.0",
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method: "notifications/initialized",
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "notifications/initialized" },
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) do |req|
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!req.headers.key?("Mcp-Name")
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end.to_return(
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status: 202,
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headers: { "Content-Type" => "application/json" },
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body: "",
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)
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client.send_request(request: request)
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end
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def test_mcp_method_header_for_initialize_without_params
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "initialize",
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "initialize" },
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) do |req|
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!req.headers.key?("Mcp-Name")
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end.to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: {} }.to_json,
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)
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client.send_request(request: request)
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end
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def test_mcp_name_header_with_string_keyed_params
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request = {
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"jsonrpc" => "2.0",
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"id" => "test_id",
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"method" => "tools/call",
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"params" => { "name" => "get_weather" },
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "tools/call", "Mcp-Name" => "get_weather" },
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).to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: {} }.to_json,
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)
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client.send_request(request: request)
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end
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def test_mcp_name_header_is_base64_encoded_when_value_has_surrounding_whitespace
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/call",
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params: { name: " padded " },
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "tools/call", "Mcp-Name" => "=?base64?IHBhZGRlZCA=?=" },
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).to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: {} }.to_json,
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)
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client.send_request(request: request)
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end
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def test_mcp_name_header_is_base64_encoded_when_value_has_crlf
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/call",
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params: { name: "evil\r\nX-Injected: 1" },
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "tools/call", "Mcp-Name" => "=?base64?ZXZpbA0KWC1JbmplY3RlZDogMQ==?=" },
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) do |req|
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!req.headers.key?("X-Injected")
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end.to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: {} }.to_json,
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)
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client.send_request(request: request)
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end
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def test_mcp_name_header_re_encodes_value_matching_base64_sentinel
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/call",
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params: { name: "=?base64?literal?=" },
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}
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stub_request(:post, url).with(
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headers: { "Mcp-Method" => "tools/call", "Mcp-Name" => "=?base64?PT9iYXNlNjQ/bGl0ZXJhbD89?=" },
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).to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: {} }.to_json,
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)
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client.send_request(request: request)
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end
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def test_mcp_method_header_without_name_for_non_hash_params
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "custom/method",
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params: ["positional"],
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}
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stub_request(:post, url).with(headers: { "Mcp-Method" => "custom/method" }) do |req|
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!req.headers.key?("Mcp-Name")
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end.to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: {} }.to_json,
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)
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client.send_request(request: request)
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end
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def test_send_request_returns_faraday_response
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/list",
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}
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stub_request(:post, url)
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.with(body: request.to_json)
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.to_return(
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status: 200,
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headers: { "Content-Type" => "application/json" },
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body: { result: { tools: [] } }.to_json,
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)
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response = client.send_request(request: request)
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assert_instance_of(Hash, response)
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assert_equal({ "result" => { "tools" => [] } }, response)
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end
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def test_send_request_raises_bad_request_error
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/list",
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}
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stub_request(:post, url)
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.with(body: request.to_json)
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.to_return(status: 400)
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error = assert_raises(RequestHandlerError) do
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client.send_request(request: request)
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end
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assert_equal("The tools/list request is invalid", error.message)
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assert_equal(:bad_request, error.error_type)
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assert_equal({ method: "tools/list", params: nil }, error.request)
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end
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|
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def test_send_request_raises_unauthorized_error
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request = {
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jsonrpc: "2.0",
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id: "test_id",
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method: "tools/list",
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}
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stub_request(:post, url)
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.with(body: request.to_json)
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.to_return(status: 401)
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error = assert_raises(RequestHandlerError) do
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client.send_request(request: request)
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end
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assert_equal("You are unauthorized to make tools/list requests", error.message)
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assert_equal(:unauthorized, error.error_type)
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assert_equal({ method: "tools/list", params: nil }, error.request)
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end
|
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|
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def test_send_request_raises_forbidden_error
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request = {
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jsonrpc: "2.0",
|
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id: "test_id",
|
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method: "tools/list",
|
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}
|
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|
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stub_request(:post, url)
|
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.with(body: request.to_json)
|
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.to_return(status: 403)
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|
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error = assert_raises(RequestHandlerError) do
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client.send_request(request: request)
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end
|
|
|
|
assert_equal("You are forbidden to make tools/list requests", error.message)
|
|
assert_equal(:forbidden, error.error_type)
|
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assert_equal({ method: "tools/list", params: nil }, error.request)
|
|
end
|
|
|
|
def test_send_request_raises_not_found_error_on_404_without_session
|
|
request = {
|
|
jsonrpc: "2.0",
|
|
id: "test_id",
|
|
method: "tools/list",
|
|
}
|
|
|
|
stub_request(:post, url)
|
|
.with(body: request.to_json)
|
|
.to_return(status: 404)
|
|
|
|
error = assert_raises(RequestHandlerError) do
|
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client.send_request(request: request)
|
|
end
|
|
|
|
refute_kind_of(SessionExpiredError, error)
|
|
assert_equal("The tools/list request is not found", error.message)
|
|
assert_equal(:not_found, error.error_type)
|
|
assert_equal({ method: "tools/list", params: nil }, error.request)
|
|
end
|
|
|
|
def test_send_request_raises_session_expired_error_on_404_with_session
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: {
|
|
"Content-Type" => "application/json",
|
|
"Mcp-Session-Id" => "session-abc",
|
|
},
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "1", method: "initialize" })
|
|
|
|
stub_request(:post, url).to_return(status: 404)
|
|
|
|
error = assert_raises(SessionExpiredError) do
|
|
client.send_request(request: { jsonrpc: "2.0", id: "2", method: "tools/list" })
|
|
end
|
|
|
|
assert_equal(:not_found, error.error_type)
|
|
end
|
|
|
|
def test_session_expired_error_is_a_request_handler_error
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: {
|
|
"Content-Type" => "application/json",
|
|
"Mcp-Session-Id" => "session-abc",
|
|
},
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "1", method: "initialize" })
|
|
|
|
stub_request(:post, url).to_return(status: 404)
|
|
|
|
error = assert_raises(RequestHandlerError) do
|
|
client.send_request(request: { jsonrpc: "2.0", id: "2", method: "tools/list" })
|
|
end
|
|
|
|
assert_kind_of(SessionExpiredError, error)
|
|
end
|
|
|
|
def test_send_request_raises_unprocessable_entity_error
|
|
request = {
|
|
jsonrpc: "2.0",
|
|
id: "test_id",
|
|
method: "tools/list",
|
|
}
|
|
|
|
stub_request(:post, url)
|
|
.with(body: request.to_json)
|
|
.to_return(status: 422)
|
|
|
|
error = assert_raises(RequestHandlerError) do
|
|
client.send_request(request: request)
|
|
end
|
|
|
|
assert_equal("The tools/list request is unprocessable", error.message)
|
|
assert_equal(:unprocessable_entity, error.error_type)
|
|
assert_equal({ method: "tools/list", params: nil }, error.request)
|
|
end
|
|
|
|
def test_send_request_raises_internal_error
|
|
request = {
|
|
jsonrpc: "2.0",
|
|
id: "test_id",
|
|
method: "tools/list",
|
|
}
|
|
|
|
stub_request(:post, url)
|
|
.with(body: request.to_json)
|
|
.to_return(status: 500)
|
|
|
|
error = assert_raises(RequestHandlerError) do
|
|
client.send_request(request: request)
|
|
end
|
|
|
|
assert_equal("Internal error handling tools/list request", error.message)
|
|
assert_equal(:internal_error, error.error_type)
|
|
assert_equal({ method: "tools/list", params: nil }, error.request)
|
|
end
|
|
|
|
def test_block_customizes_faraday_connection
|
|
custom_client = HTTP.new(url: url) do |faraday|
|
|
faraday.headers["X-Custom"] = "test-value"
|
|
end
|
|
|
|
request = {
|
|
jsonrpc: "2.0",
|
|
id: "test_id",
|
|
method: "tools/list",
|
|
}
|
|
|
|
stub_request(:post, url).with(
|
|
headers: {
|
|
"X-Custom" => "test-value",
|
|
"Accept" => "application/json, text/event-stream",
|
|
},
|
|
).to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json" },
|
|
body: { result: { tools: [] } }.to_json,
|
|
)
|
|
|
|
custom_client.send_request(request: request)
|
|
end
|
|
|
|
def test_send_request_raises_error_for_unsupported_content_type
|
|
request = {
|
|
jsonrpc: "2.0",
|
|
id: "test_id",
|
|
method: "tools/list",
|
|
}
|
|
|
|
stub_request(:post, url)
|
|
.with(body: request.to_json)
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "text/html" },
|
|
body: "<html></html>",
|
|
)
|
|
|
|
error = assert_raises(RequestHandlerError) do
|
|
client.send_request(request: request)
|
|
end
|
|
|
|
assert_equal(
|
|
'Unsupported Content-Type: "text/html". Expected application/json or text/event-stream.',
|
|
error.message,
|
|
)
|
|
assert_equal(:unsupported_media_type, error.error_type)
|
|
assert_equal({ method: "tools/list", params: nil }, error.request)
|
|
end
|
|
|
|
def test_send_request_parses_sse_response
|
|
request = {
|
|
jsonrpc: "2.0",
|
|
id: "test_id",
|
|
method: "tools/list",
|
|
}
|
|
|
|
sse_body = <<~SSE
|
|
: comment
|
|
data: {"jsonrpc":"2.0","method":"notifications/progress","params":{}}
|
|
|
|
data: {"jsonrpc":"2.0","id":"test_id","result":{"tools":[{"name":"echo"}]}}
|
|
|
|
SSE
|
|
|
|
stub_request(:post, url)
|
|
.with(body: request.to_json)
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "text/event-stream" },
|
|
body: sse_body,
|
|
)
|
|
|
|
response = client.send_request(request: request)
|
|
|
|
assert_equal({ "tools" => [{ "name" => "echo" }] }, response["result"])
|
|
end
|
|
|
|
def test_send_request_parses_sse_error_response
|
|
request = {
|
|
jsonrpc: "2.0",
|
|
id: "test_id",
|
|
method: "tools/list",
|
|
}
|
|
|
|
sse_body = <<~SSE
|
|
data: {"jsonrpc":"2.0","id":"test_id","error":{"code":-32600,"message":"Invalid request"}}
|
|
|
|
SSE
|
|
|
|
stub_request(:post, url)
|
|
.with(body: request.to_json)
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "text/event-stream" },
|
|
body: sse_body,
|
|
)
|
|
|
|
response = client.send_request(request: request)
|
|
|
|
assert_equal(-32600, response.dig("error", "code"))
|
|
assert_equal("Invalid request", response.dig("error", "message"))
|
|
end
|
|
|
|
def test_send_request_returns_nil_for_202_accepted_response
|
|
request = {
|
|
jsonrpc: "2.0",
|
|
method: "notifications/initialized",
|
|
}
|
|
|
|
stub_request(:post, url)
|
|
.with(body: request.to_json)
|
|
.to_return(status: 202, body: "")
|
|
|
|
response = client.send_request(request: request)
|
|
|
|
assert_nil(response)
|
|
end
|
|
|
|
def test_send_request_raises_error_for_sse_without_response
|
|
request = {
|
|
jsonrpc: "2.0",
|
|
id: "test_id",
|
|
method: "tools/list",
|
|
}
|
|
|
|
sse_body = <<~SSE
|
|
: just a comment
|
|
data: {"jsonrpc":"2.0","method":"notifications/progress","params":{}}
|
|
|
|
SSE
|
|
|
|
stub_request(:post, url)
|
|
.with(body: request.to_json)
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "text/event-stream" },
|
|
body: sse_body,
|
|
)
|
|
|
|
error = assert_raises(RequestHandlerError) do
|
|
client.send_request(request: request)
|
|
end
|
|
|
|
assert_includes(error.message, "No valid JSON-RPC response found in SSE stream")
|
|
assert_equal(:parse_error, error.error_type)
|
|
end
|
|
|
|
def test_captures_session_id_and_protocol_version_on_initialize
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: {
|
|
"Content-Type" => "application/json",
|
|
"Mcp-Session-Id" => "session-abc",
|
|
},
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "1", method: "initialize" })
|
|
|
|
assert_equal("session-abc", client.session_id)
|
|
assert_equal("2025-11-25", client.protocol_version)
|
|
end
|
|
|
|
def test_includes_session_and_protocol_version_headers_after_initialize
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: {
|
|
"Content-Type" => "application/json",
|
|
"Mcp-Session-Id" => "session-abc",
|
|
},
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "1", method: "initialize" })
|
|
|
|
stub_request(:post, url)
|
|
.with(
|
|
headers: {
|
|
"Mcp-Session-Id" => "session-abc",
|
|
"MCP-Protocol-Version" => "2025-11-25",
|
|
},
|
|
)
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json" },
|
|
body: { result: { tools: [] } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "2", method: "tools/list" })
|
|
end
|
|
|
|
def test_does_not_send_protocol_version_header_before_initialize
|
|
stub_request(:post, url)
|
|
.with { |req| !req.headers.keys.map(&:downcase).include?("mcp-protocol-version") }
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json" },
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "1", method: "initialize" })
|
|
end
|
|
|
|
def test_ignores_empty_session_id_header
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: {
|
|
"Content-Type" => "application/json",
|
|
"Mcp-Session-Id" => "",
|
|
},
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "1", method: "initialize" })
|
|
|
|
assert_nil(client.session_id)
|
|
end
|
|
|
|
def test_session_id_not_overwritten_by_subsequent_responses
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: {
|
|
"Content-Type" => "application/json",
|
|
"Mcp-Session-Id" => "original-session",
|
|
},
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "1", method: "initialize" })
|
|
|
|
assert_equal("original-session", client.session_id)
|
|
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: {
|
|
"Content-Type" => "application/json",
|
|
"Mcp-Session-Id" => "different-session",
|
|
},
|
|
body: { result: { tools: [] } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "2", method: "tools/list" })
|
|
|
|
assert_equal("original-session", client.session_id)
|
|
end
|
|
|
|
def test_stateless_server_without_session_id_header
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json" },
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "1", method: "initialize" })
|
|
|
|
assert_nil(client.session_id)
|
|
assert_equal("2025-11-25", client.protocol_version)
|
|
end
|
|
|
|
def test_clears_session_state_on_404
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: {
|
|
"Content-Type" => "application/json",
|
|
"Mcp-Session-Id" => "session-abc",
|
|
},
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "1", method: "initialize" })
|
|
|
|
assert_equal("session-abc", client.session_id)
|
|
|
|
stub_request(:post, url).to_return(status: 404)
|
|
|
|
assert_raises(SessionExpiredError) do
|
|
client.send_request(request: { jsonrpc: "2.0", id: "2", method: "tools/list" })
|
|
end
|
|
|
|
assert_nil(client.session_id)
|
|
assert_nil(client.protocol_version)
|
|
end
|
|
|
|
def test_close_sends_delete_with_session_headers
|
|
initialize_session
|
|
|
|
stub_request(:delete, url)
|
|
.with(
|
|
headers: {
|
|
"Mcp-Session-Id" => "session-abc",
|
|
"MCP-Protocol-Version" => "2025-11-25",
|
|
},
|
|
)
|
|
.to_return(status: 200)
|
|
|
|
client.close
|
|
end
|
|
|
|
def test_close_clears_session_state
|
|
initialize_session
|
|
stub_request(:delete, url).to_return(status: 200)
|
|
|
|
client.close
|
|
|
|
assert_nil(client.session_id)
|
|
assert_nil(client.protocol_version)
|
|
end
|
|
|
|
def test_close_without_session_is_noop
|
|
client.close
|
|
|
|
assert_not_requested(:delete, url)
|
|
assert_nil(client.session_id)
|
|
end
|
|
|
|
def test_close_clears_stateless_connection_state
|
|
stub_request(:post, url)
|
|
.with { |req| JSON.parse(req.body)["method"] == "initialize" }
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json" },
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
stub_notification
|
|
|
|
client.connect
|
|
client.close
|
|
|
|
assert_not_requested(:delete, url)
|
|
refute_predicate(client, :connected?)
|
|
assert_nil(client.protocol_version)
|
|
assert_nil(client.server_info)
|
|
end
|
|
|
|
def test_close_tolerates_405_response
|
|
initialize_session
|
|
stub_request(:delete, url).to_return(status: 405)
|
|
|
|
client.close
|
|
|
|
assert_nil(client.session_id)
|
|
end
|
|
|
|
def test_close_tolerates_404_response
|
|
initialize_session
|
|
stub_request(:delete, url).to_return(status: 404)
|
|
|
|
client.close
|
|
|
|
assert_nil(client.session_id)
|
|
end
|
|
|
|
def test_close_propagates_server_error_and_still_clears_state
|
|
initialize_session
|
|
stub_request(:delete, url).to_return(status: 500)
|
|
|
|
assert_raises(Faraday::ServerError) do
|
|
client.close
|
|
end
|
|
|
|
assert_nil(client.session_id)
|
|
assert_nil(client.protocol_version)
|
|
end
|
|
|
|
def test_close_propagates_unauthorized_and_still_clears_state
|
|
initialize_session
|
|
stub_request(:delete, url).to_return(status: 401)
|
|
|
|
assert_raises(Faraday::UnauthorizedError) do
|
|
client.close
|
|
end
|
|
|
|
assert_nil(client.session_id)
|
|
end
|
|
|
|
def test_close_propagates_connection_failure_and_still_clears_state
|
|
initialize_session
|
|
stub_request(:delete, url).to_raise(Faraday::ConnectionFailed.new("connection refused"))
|
|
|
|
assert_raises(Faraday::ConnectionFailed) do
|
|
client.close
|
|
end
|
|
|
|
assert_nil(client.session_id)
|
|
end
|
|
|
|
def test_close_is_idempotent
|
|
initialize_session
|
|
stub_request(:delete, url).to_return(status: 200)
|
|
|
|
client.close
|
|
client.close
|
|
|
|
assert_requested(:delete, url, times: 1)
|
|
end
|
|
|
|
def test_connect_performs_initialize_handshake
|
|
init_stub = stub_request(:post, url)
|
|
.with { |req| JSON.parse(req.body)["method"] == "initialize" }
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json", "Mcp-Session-Id" => "s1" },
|
|
body: {
|
|
result: {
|
|
protocolVersion: "2025-11-25",
|
|
capabilities: { tools: {} },
|
|
serverInfo: { name: "test-server", version: "1.0" },
|
|
},
|
|
}.to_json,
|
|
)
|
|
|
|
notification_stub = stub_request(:post, url)
|
|
.with { |req| JSON.parse(req.body)["method"] == "notifications/initialized" }
|
|
.to_return(status: 202, body: "")
|
|
|
|
result = client.connect
|
|
|
|
assert_requested(init_stub)
|
|
assert_requested(notification_stub)
|
|
assert_equal("2025-11-25", result["protocolVersion"])
|
|
assert_equal({ "tools" => {} }, result["capabilities"])
|
|
assert_equal({ "name" => "test-server", "version" => "1.0" }, result["serverInfo"])
|
|
end
|
|
|
|
def test_connect_caches_server_info
|
|
stub_initialize
|
|
stub_notification
|
|
|
|
client.connect
|
|
|
|
assert_equal("2025-11-25", client.server_info["protocolVersion"])
|
|
end
|
|
|
|
def test_connect_uses_default_client_info_and_protocol_version
|
|
notification_stub = stub_notification
|
|
|
|
init_stub = stub_request(:post, url)
|
|
.with do |req|
|
|
body = JSON.parse(req.body)
|
|
body["method"] == "initialize" &&
|
|
body["params"]["protocolVersion"] == MCP::Configuration::LATEST_STABLE_PROTOCOL_VERSION &&
|
|
body["params"]["clientInfo"] == { "name" => "mcp-ruby-client", "version" => MCP::VERSION } &&
|
|
body["params"]["capabilities"] == {}
|
|
end
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json" },
|
|
body: { result: { protocolVersion: MCP::Configuration::LATEST_STABLE_PROTOCOL_VERSION } }.to_json,
|
|
)
|
|
|
|
client.connect
|
|
|
|
assert_requested(init_stub)
|
|
assert_requested(notification_stub)
|
|
end
|
|
|
|
def test_connect_accepts_custom_parameters
|
|
notification_stub = stub_notification
|
|
|
|
init_stub = stub_request(:post, url)
|
|
.with do |req|
|
|
body = JSON.parse(req.body)
|
|
body["method"] == "initialize" &&
|
|
body["params"]["protocolVersion"] == "2025-03-26" &&
|
|
body["params"]["clientInfo"] == { "name" => "my-app", "version" => "9.9" } &&
|
|
body["params"]["capabilities"] == { "roots" => { "listChanged" => true } }
|
|
end
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json" },
|
|
body: { result: { protocolVersion: "2025-03-26" } }.to_json,
|
|
)
|
|
|
|
client.connect(
|
|
client_info: { name: "my-app", version: "9.9" },
|
|
protocol_version: "2025-03-26",
|
|
capabilities: { roots: { listChanged: true } },
|
|
)
|
|
|
|
assert_requested(init_stub)
|
|
assert_requested(notification_stub)
|
|
end
|
|
|
|
def test_connect_is_idempotent
|
|
init_stub = stub_initialize
|
|
notification_stub = stub_notification
|
|
|
|
first_result = client.connect
|
|
second_result = client.connect
|
|
|
|
assert_same(first_result, second_result)
|
|
assert_requested(init_stub, times: 1)
|
|
assert_requested(notification_stub, times: 1)
|
|
end
|
|
|
|
def test_connect_raises_on_jsonrpc_error_response
|
|
stub_request(:post, url).to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json", "Mcp-Session-Id" => "session-abc" },
|
|
body: { error: { code: -32602, message: "Unsupported protocol version" } }.to_json,
|
|
)
|
|
|
|
error = assert_raises(RequestHandlerError) do
|
|
client.connect
|
|
end
|
|
|
|
assert_includes(error.message, "Unsupported protocol version")
|
|
refute_predicate(client, :connected?)
|
|
assert_nil(client.session_id)
|
|
assert_nil(client.protocol_version)
|
|
assert_nil(client.server_info)
|
|
end
|
|
|
|
def test_connect_raises_on_missing_result
|
|
stub_request(:post, url).to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json", "Mcp-Session-Id" => "session-abc" },
|
|
body: { jsonrpc: "2.0", id: "x" }.to_json,
|
|
)
|
|
|
|
error = assert_raises(RequestHandlerError) do
|
|
client.connect
|
|
end
|
|
|
|
assert_includes(error.message, "missing result in response")
|
|
refute_predicate(client, :connected?)
|
|
assert_nil(client.session_id)
|
|
assert_nil(client.protocol_version)
|
|
assert_nil(client.server_info)
|
|
end
|
|
|
|
def test_connect_raises_on_unsupported_negotiated_protocol_version
|
|
stub_request(:post, url)
|
|
.with { |req| JSON.parse(req.body)["method"] == "initialize" }
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json", "Mcp-Session-Id" => "session-abc" },
|
|
body: { result: { protocolVersion: "2099-01-01" } }.to_json,
|
|
)
|
|
|
|
error = assert_raises(RequestHandlerError) do
|
|
client.connect
|
|
end
|
|
|
|
assert_includes(error.message, 'unsupported protocol version "2099-01-01"')
|
|
refute_predicate(client, :connected?)
|
|
assert_nil(client.session_id)
|
|
assert_nil(client.protocol_version)
|
|
assert_nil(client.server_info)
|
|
end
|
|
|
|
def test_connect_clears_session_when_initialized_notification_fails
|
|
stub_initialize
|
|
stub_request(:post, url)
|
|
.with { |req| JSON.parse(req.body)["method"] == "notifications/initialized" }
|
|
.to_return(status: 500)
|
|
|
|
assert_raises(RequestHandlerError) do
|
|
client.connect
|
|
end
|
|
|
|
refute_predicate(client, :connected?)
|
|
assert_nil(client.session_id)
|
|
assert_nil(client.protocol_version)
|
|
assert_nil(client.server_info)
|
|
end
|
|
|
|
def test_connected_lifecycle
|
|
refute_predicate(client, :connected?)
|
|
|
|
stub_initialize
|
|
stub_notification
|
|
client.connect
|
|
|
|
assert_predicate(client, :connected?)
|
|
|
|
stub_request(:delete, url).to_return(status: 200)
|
|
client.close
|
|
|
|
refute_predicate(client, :connected?)
|
|
end
|
|
|
|
def test_reconnect_after_close
|
|
stub_initialize
|
|
stub_notification
|
|
client.connect
|
|
stub_request(:delete, url).to_return(status: 200)
|
|
client.close
|
|
|
|
stub_request(:post, url)
|
|
.with { |req| JSON.parse(req.body)["method"] == "initialize" }
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json", "Mcp-Session-Id" => "s2" },
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.connect
|
|
|
|
assert_predicate(client, :connected?)
|
|
assert_equal("s2", client.session_id)
|
|
end
|
|
|
|
def test_close_allows_reinitializing_a_fresh_session
|
|
initialize_session
|
|
stub_request(:delete, url).to_return(status: 200)
|
|
client.close
|
|
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: {
|
|
"Content-Type" => "application/json",
|
|
"Mcp-Session-Id" => "session-xyz",
|
|
},
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "2", method: "initialize" })
|
|
|
|
assert_equal("session-xyz", client.session_id)
|
|
assert_equal("2025-11-25", client.protocol_version)
|
|
end
|
|
|
|
def test_send_notification_posts_body_and_accepts_202
|
|
notification = {
|
|
jsonrpc: "2.0",
|
|
method: MCP::Methods::NOTIFICATIONS_CANCELLED,
|
|
params: { requestId: "req-1", reason: "user cancel" },
|
|
}
|
|
|
|
stub_request(:post, url).with(body: notification.to_json).to_return(status: 202, body: "")
|
|
|
|
result = client.send_notification(notification: notification)
|
|
|
|
assert_nil(result, "send_notification must return nil")
|
|
end
|
|
|
|
def test_send_notification_surfaces_faraday_errors
|
|
notification = {
|
|
jsonrpc: "2.0",
|
|
method: MCP::Methods::NOTIFICATIONS_CANCELLED,
|
|
params: { requestId: "req-1" },
|
|
}
|
|
|
|
stub_request(:post, url).to_return(status: 500)
|
|
|
|
error = assert_raises(RequestHandlerError) do
|
|
client.send_notification(notification: notification)
|
|
end
|
|
|
|
assert_equal(:internal_error, error.error_type)
|
|
assert_match(%r{notifications/cancelled}, error.message)
|
|
end
|
|
|
|
private
|
|
|
|
def initialize_session
|
|
stub_request(:post, url)
|
|
.to_return(
|
|
status: 200,
|
|
headers: {
|
|
"Content-Type" => "application/json",
|
|
"Mcp-Session-Id" => "session-abc",
|
|
},
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
|
|
client.send_request(request: { jsonrpc: "2.0", id: "1", method: "initialize" })
|
|
end
|
|
|
|
def stub_initialize
|
|
stub_request(:post, url)
|
|
.with { |req| JSON.parse(req.body)["method"] == "initialize" }
|
|
.to_return(
|
|
status: 200,
|
|
headers: { "Content-Type" => "application/json", "Mcp-Session-Id" => "session-abc" },
|
|
body: { result: { protocolVersion: "2025-11-25" } }.to_json,
|
|
)
|
|
end
|
|
|
|
def stub_notification
|
|
stub_request(:post, url)
|
|
.with { |req| JSON.parse(req.body)["method"] == "notifications/initialized" }
|
|
.to_return(status: 202, body: "")
|
|
end
|
|
|
|
def stub_request(method, url)
|
|
WebMock.stub_request(method, url)
|
|
end
|
|
|
|
def url
|
|
"http://example.com"
|
|
end
|
|
|
|
def client
|
|
@client ||= HTTP.new(url: url)
|
|
end
|
|
end
|
|
end
|
|
end
|