mcp: allow restricting the protocol versions a server supports - #1199
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guglielmo-san wants to merge 9 commits into
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mcp: allow restricting the protocol versions a server supports#1199guglielmo-san wants to merge 9 commits into
guglielmo-san wants to merge 9 commits into
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…ted and advertised protocol versions
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…lVersions function call
…function was deprecated or removed
…ntation for better fallback behavior
…nsure consistent version matching
…nsport and simplify documentation regarding version negotiation
…upported versions in shared.go
| // supported is the set of protocol versions the server negotiates, newest | ||
| // first, so that a connection deriving the session's effective version | ||
| // reaches the same answer the initialize handshake did. | ||
| sessionUpdated(state ServerSessionState, supported []string) |
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doesn't look clean. I'd rather we add a new field to session state:
type ServerSessionState struct {
...
NegotiatedProtocolVersion string `json:"negotiatedProtocolVersion,omitempty"`
}
compute it on initialize, and in sessionUpdated the logic becomes
protocolVersion := state.NegotiatedProtocolVersion
if protocolVersion == "" { // the last spec version that did not protocol-version header
protocolVersion = protocolVersion20250326
}| return !slices.Contains(opts.SupportedProtocolVersions, v) | ||
| }) | ||
| } | ||
| if len(protocolVersions) == 0 { |
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this is unreachable if len(opts.SupportedProtocolVersions) > 0 and all elements are present in supportedProtocolVersions
| // to those listed. If empty, every version supported by this version of the | ||
| // SDK is used. | ||
| // | ||
| // The value can only narrow support, never widen it: [NewServer] panics if |
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Let's reference [SupportedProtocolVersions] as the source of valid values.
| // (i.e. exclude 2026-07-28, since that's what the request asked for | ||
| // and what we're rejecting). | ||
| legacyVersions := slices.DeleteFunc(slices.Clone(supportedProtocolVersions), func(v string) bool { | ||
| advertised := supportedProtocolVersions |
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line 371 in this file needs to be updated, currently checks supportedProtocolVersions ignoring server opts
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Fixes #945