MCP registry

package com.example.tnsai.docs;

import com.tnsai.mcp.registry.McpRegistrySource;
import com.tnsai.mcp.registry.McpServerEntry;
import com.tnsai.mcp.registry.OfficialRegistryClient;
import com.tnsai.mcp.registry.SmitheryClient;
import com.tnsai.mcp.registry.UnifiedMcpRegistry;
import java.time.Duration;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Optional;

/** Compilation contract for mcp/registry.md. */
public final class McpRegistryExample {

    private McpRegistryExample() {
    }

    static Optional<String> findEndpoint() {
        UnifiedMcpRegistry registry = new UnifiedMcpRegistry();          // all four public sources
        List<McpServerEntry> hits = registry.search("filesystem");
        hits.forEach(e -> System.out.println(e.name() + " (" + e.source() + "): " + e.endpoint()));
        return registry.getServer("filesystem").map(McpServerEntry::endpoint);
    }

    public static final class InternalCatalog implements McpRegistrySource {

        private final List<McpServerEntry> entries = List.of(new McpServerEntry(
            "billing", "Billing tools", "2.1.0", null, "streamable-http",
            "https://mcp.internal.example.com/billing", "internal", 0.0, Map.of("team", "payments")));

        @Override
        public String getSourceName() {
            return "internal";
        }

        @Override
        public List<McpServerEntry> search(String query) {
            String q = query == null ? "" : query.toLowerCase(Locale.ROOT);
            return entries.stream().filter(e -> e.name().contains(q)).toList();
        }

        @Override
        public Optional<McpServerEntry> getServer(String name) {
            return entries.stream().filter(e -> e.name().equals(name)).findFirst();
        }

        @Override
        public List<McpServerEntry> listAll() {
            return entries;
        }
    }

    static UnifiedMcpRegistry customSources() {
        UnifiedMcpRegistry registry = new UnifiedMcpRegistry(
            List.of(new OfficialRegistryClient(), new SmitheryClient()),
            Duration.ofMinutes(5));
        registry.addSource(new InternalCatalog());
        registry.removeSource("smithery");
        registry.clearCache();                    // the next search asks the sources again
        return registry;
    }
}