dc4386f0f1Update Kotlin-MCP-Server with STDIO support, logging & CORS ### Summary - Added support for STDIO transport mode (default behavior). - Configured CORS and migrated SSE server to Ktor's Netty engine. - Redirected logs to `./build/stdout.log` and updated log levels. - New `TestEnvironment` setup for integration testing. - Enhanced documentation with examples for server execution and MCP Inspector usage. - Introduced shadow JAR plugin for building runnable artifacts. ### Motivation and Context Improves server versatility and developer experience by enabling STDIO and refining setup. ## How Has This Been Tested? Unit tests, tested locally (see README.md in sample) **NB! sse plain configuration is not working at the moment** ## Breaking Changes No ## Types of changes <!-- What types of changes does your code introduce? Put an `x` in all the boxes that apply: --> - [x] Bug fix (non-breaking change which fixes an issue) - [ ] New feature (non-breaking change which adds functionality) - [ ] Breaking change (fix or feature that would cause existing functionality to change) - [ ] Documentation update ## Checklist <!-- Go over all the following points, and put an `x` in all the boxes that apply. --> - [ ] I have read the [MCP Documentation](https://modelcontextprotocol.io) - [ ] My code follows the repository's style guidelines - [ ] New and existing tests pass locally - [ ] I have added appropriate error handling - [ ] I have added or updated documentation as needed ## Additional context <!-- Add any other context, implementation notes, or design decisions -->
93 lines
2.9 KiB
Markdown
93 lines
2.9 KiB
Markdown
# MCP Kotlin Server Sample
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A sample implementation of an MCP (Model Context Protocol) server in Kotlin that demonstrates different server
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configurations and transport methods.
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## Features
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- Multiple server operation modes:
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- Standard I/O server
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- SSE (Server-Sent Events) server with plain configuration
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- SSE server using Ktor plugin
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- Built-in capabilities for:
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- Prompts management
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- Resources handling
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- Tools integration
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## Getting Started
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### Running the Server
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The server defaults [STDIO transport](https://modelcontextprotocol.io/specification/2025-06-18/basic/transports#stdio).
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You can customize the behavior using command-line arguments.
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Logs are printed to [./build/stdout.log](./build/stdout.log)
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#### Standard I/O mode (STDIO):
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```bash
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./gradlew clean build
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```
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Use the [MCP inspector](https://modelcontextprotocol.io/docs/tools/inspector)
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to connect to MCP via STDIO (Click the "▶️ Connect" button):
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```shell
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npx @modelcontextprotocol/inspector --config mcp-inspector-config.json --server stdio-server
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```
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#### SSE with plain configuration:
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**NB!: 🐞 This configuration may not work ATM**
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```bash
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./gradlew run --args="--sse-server 3001"
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```
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or
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```shell
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./gradlew clean build
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java -jar ./build/libs/kotlin-mcp-server-0.1.0-all.jar --sse-server 3001
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```
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Use the [MCP inspector](https://modelcontextprotocol.io/docs/tools/inspector)
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to connect to `http://localhost:3002/` via SSE Transport (Click the "▶️ Connect" button):
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```shell
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npx @modelcontextprotocol/inspector --config mcp-inspector-config.json --server sse-server
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```
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#### SSE with Ktor plugin:
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```bash
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./gradlew run --args="--sse-server-ktor 3002"
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```
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or
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```shell
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./gradlew clean build
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java -jar ./build/libs/kotlin-mcp-server-0.1.0-all.jar --sse-server-ktor 3002
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```
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Use the [MCP inspector](https://modelcontextprotocol.io/docs/tools/inspector)
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to connect to `http://localhost:3002/` via SSE transport (Click the "▶️ Connect" button):
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```shell
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npx @modelcontextprotocol/inspector --config mcp-inspector-config.json --server sse-ktor-server
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```
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## Server Capabilities
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- **Prompts**: Supports prompt management with list change notifications
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- **Resources**: Includes subscription support and list change notifications
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- **Tools**: Supports tool management with list change notifications
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## Implementation Details
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The server is implemented using:
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- Ktor for HTTP server functionality (SSE modes)
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- Kotlin coroutines for asynchronous operations
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- SSE for real-time communication in web contexts
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- Standard I/O for command-line interface and process-based communication
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## Example Capabilities
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The sample server demonstrates:
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- **Prompt**: "Kotlin Developer" - helps develop small Kotlin applications with a configurable project name
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- **Tool**: "kotlin-sdk-tool" - a simple test tool that returns a greeting
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- **Resource**: "Web Search" - a placeholder resource demonstrating resource handling
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