Route MCP resource subscribe/unsubscribe through Rust gateway - #40
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Is this valid implementation... and how is this going to work if the customer wants to subscribe to changes on two different MCP servers
Replace the local in-memory subscription set with real backend routing: subscribe/unsubscribe now validate the request, split the namespaced resource URI, resolve the single owning backend, and forward the call with the prefix stripped, returning backend and routing errors instead of reporting local-only success. Mirrors read_resource/get_prompt and drops the now-unused subscriptions HashSet field. The mock backend gains subscribe/unsubscribe handlers that only accept its own backend-local URIs, and a new integration test proves a namespaced subscribe/unsubscribe round-trips to the backend and that an unrouted URI fails with a gateway routing error. Implements IBM/mcp-context-forge#5253 Signed-off-by: lucarlig <luca.carlig@ibm.com>
Now that subscribe/unsubscribe route to backends, declare the resources.subscribe server capability so spec-compliant clients discover and use the feature. Signed-off-by: lucarlig <luca.carlig@ibm.com>
Signed-off-by: lucarlig <luca.carlig@ibm.com>
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Signed-off-by: lucarlig <luca.carlig@ibm.com>
call_tool, read_resource, get_prompt, complete, subscribe, and unsubscribe all repeated the same split-prefix/resolve-backend preamble; extract it into route_prefixed_name. Signed-off-by: lucarlig <luca.carlig@ibm.com>
The mock backend now notifies on an interval and deliberately keeps notifying after unsubscribe, so the round-trip test can assert the gateway itself stops forwarding updates for unsubscribed URIs. This also decouples the test's update threshold from a hardcoded mock notification count. Signed-off-by: lucarlig <luca.carlig@ibm.com>
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@dawid-nowak we were just forwarding the sub unsub no forwarding changes derived from subscription, i have implemented that now |
Add prefixed_name as the inverse of split_prefixed_name and route all namespace joins through it, share one backend_forward_error helper across the forwarding handlers, make subscription tracking take &str, and reuse the support connect/config helpers instead of per-test copies. Signed-off-by: lucarlig <luca.carlig@ibm.com>
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Route MCP
resources/subscribeandresources/unsubscribethrough the Rust gateway, replacing the local in-memory subscription set.subscribe/unsubscribenow validate the request, split the namespaced resource URI, resolve the single owning backend (split_prefixed_name+resolve_backend), and forward the call with the prefix stripped — returning backend and routing errors instead of local-only success. Mirrorsread_resource/get_prompt.subscriptionsHashSetfield.Implements IBM/mcp-context-forge#5253