Wire mcpServerJsonMapper into stateless MCP server builders#5895
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PVPankaj wants to merge 1 commit intospring-projects:mainfrom
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Wire mcpServerJsonMapper into stateless MCP server builders#5895PVPankaj wants to merge 1 commit intospring-projects:mainfrom
PVPankaj wants to merge 1 commit intospring-projects:mainfrom
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McpServerStatelessAutoConfiguration did not pass the configured mcpServerJsonMapper to the McpServer builder, causing the handler stage to fall back to a strict default ObjectMapper. This rejected unknown fields from MCP clients implementing the 2025-11-25 spec (e.g. Codex), breaking the initialize handshake. Add @qualifier("mcpServerJsonMapper") JsonMapper parameter and .jsonMapper(new JacksonMcpJsonMapper(...)) call to both the sync and async stateless server bean methods, consistent with how the stdio transport is already wired in McpServerAutoConfiguration. Closes spring-projectsgh-5894 Signed-off-by: Pankaj <pankajvpande@gmail.com>
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McpServerStatelessAutoConfigurationbuilds the stateless sync and asyncMcpServerwithout calling.jsonMapper(...). This causes the handler stage (e.g.convertValue(req, InitializeRequest.class)) to fall back toMcpJsonMapper.getDefault()- a strict vanilla ObjectMapper withFAIL_ON_UNKNOWN_PROPERTIES=true.Meanwhile, the transport layer correctly uses the lenient
mcpServerJsonMapperbean. So we end up with two different mappers at different stages:JSONRPCRequest: lenient mapper ✅params->InitializeRequest: strict default ❌Any MCP client implementing the 2025-11-25 spec (e.g. Codex) sends fields like
capabilities.elicitation.formthat the current SDK records don't model yet, so the strict mapper rejects them and the initialize handshake fails with:This change adds
@Qualifier("mcpServerJsonMapper") JsonMapperto bothmcpStatelessSyncServerandmcpStatelessAsyncServerbean methods and wires it via.jsonMapper(new JacksonMcpJsonMapper(...))on the builder - the same pattern already used byMcpServerAutoConfigurationfor the stdio transport.Closes gh-5894