tinystruct-patterns

name tinystruct-patterns description Expert guidance for developing with the tinystruct Java framework. Use when working on the tinystruct codebase or any project built on tinystruct — including creating Application classes, @Action-mapped routes, unit tests, ActionRegistry, HTTP/CLI dual-mode handling, the built-in HTTP server, the event system, JSON with Builder/Builders, database persistence with AbstractData, POJO generation, Server-Sent Events (SSE), file uploads, and outbound HTTP networking. metadata {"origin":"ECC"} tinystruct Development Patterns Architecture and implementation patterns for building modules with the tinystruct Java framework – a lightweight, high-performance framework that treats CLI and HTTP as equal citizens, requiring no main() method and minimal configuration. Core Principle CLI and HTTP are equal citizens. Every method annotated with @Action should ideally be runnable from both a terminal and a web browser without modification. This "dual-mode" capability is the core design philosophy of tinystruct. When to Activate When to Use Creating new Application modules by extending AbstractApplication . Defining routes and command-line actions using @Action . Handling per-request state via Context . Performing JSON serialization using the native Builder and Builders components. Working with database persistence via AbstractData POJOs. Generating POJOs from database tables using the generate command. Implementing Server-Sent Events (SSE) for real-time push. Handling file uploads via multipart data. Making outbound HTTP requests with URLRequest and HTTPHandler . Configuring database connections or system settings in application.properties . Debugging routing conflicts (Actions) or CLI argument parsing. How It Works The tinystruct framework treats any method annotated with @Action as a routable endpoint for both terminal and web environments. Applications are created by extending AbstractApplication , which provides core lifecycle hooks like init() and access to the request Context . Routing is handled by the ActionRegistry , which automatically maps path segments to method arguments and injects dependencies. For data-only services, the native Builder and Builders components should be used for JSON serialization to maintain a zero-dependency footprint. The database layer uses AbstractData POJOs paired with XML mapping files for CRUD operations without external ORM libraries. Examples Basic Application (MyService) public class MyService extends AbstractApplication { @Override public void init () { this .setTemplateRequired( false ); // Disable .view lookup for data/API apps } @Override public String version () { return "1.0.0" ; } @Action("greet") public String greet () { return "Hello from tinystruct!" ; } // Path parameter: GET /?q=greet/James OR bin/dispatcher greet/James @Action("greet") public String greet (String name) { return "Hello, " + name + "!" ; } } HTTP Mode Disambiguation (login) @Action(value = "login", mode = Mode.HTTP_POST) public String doLogin (Request<?, ?> request) throws ApplicationException { request.getSession().setAttribute( "userId" , "42" ); return "Logged in" ; } Native JSON Data Handling (Builder + Builders) import org.tinystruct.data.component.Builder; import org.tinystruct.data.component.Builders; @Action("api/data") public String getData () throws ApplicationException { Builders dataList = new Builders (); Builder item = new Builder (); item.put( "id" , 1 ); item.put( "name" , "James" ); dataList.add(item); Builder response = new Builder (); response.put( "status" , "success" ); response.put( "data" , dataList); return response.toString(); // {"status":"success","data":[{"id":1,"name":"James"}]} } SSE (Server-Sent Events) import org.tinystruct.http.SSEPushManager; @Action("sse/connect") public String connect () { return "{\"type\":\"connect\",\"message\":\"Connected to SSE\"}" ; } // Push to a specific client String sessionId = getContext().getId(); Builder msg = new Builder (); msg.put( "text" , "Hello, user!" ); SSEPushManager.getInstance().push(sessionId, msg); // Broadcast to all // Broadcast to all SSEPushManager.getInstance().broadcast(msg); File Upload import org.tinystruct.data.FileEntity; @Action(value = "upload", mode = Mode.HTTP_POST) public String upload (Request<?, ?> request) throws ApplicationException { List<FileEntity> files = request.getAttachments(); if (files != null ) { for (FileEntity file : files) { System.out.println( "Uploaded: " + file.getFilename()); } } return "Upload OK" ; } MCP Server and Tools Integration tinystruct provides native support for the Model Context Protocol (MCP) starting with SDK version 1.7.26 . The MCP APIs (e.g., org.tinystruct.mcp.MCPTool , org.tinystruct.mcp.MCPServer , org.tinystruct.mcp.MCPException ) are included directly in the core dependency: < dependency > < groupId > org.tinystruct </ groupId > < artifactId > tinystruct </ artifactId > < version > 1.7.26 </ version > </ dependency > SECURITY WARNING (Prompt Injection): Tool return values are fed directly back into the AI model's context window. You MUST validate and sanitize all caller-supplied arguments before including them in the tool's return string. Failure to sanitize inputs can allow an attacker to inject adversarial instructions (Prompt Injection) that override the model's behavior. Always validate length, character sets, and nullity. To create an MCP Tool: Extend org.tinystruct.mcp.MCPTool . Annotate operations with @Action and declare parameters using @Argument within the arguments array. Accept parameters as explicit method arguments matching the keys in @Argument . (Do not use getContext().getAttribute(...) for tool arguments). import org.tinystruct.mcp.MCPTool; import org.tinystruct.mcp.MCPException; import org.tinystruct.system.annotation.Action; import org.tinystruct.system.annotation.Argument; public class MyCustomTool extends MCPTool { public MyCustomTool () { super ( "custom" , "A custom tool for demonstrating MCP" ); } @Action( value = "custom/hello", description = "Say hello to someone", arguments = { @Argument(key = "name", description = "The name to greet", type = "string", optional = false) } ) public String hello (String name) throws MCPException { // SECURITY: Validate/sanitize tool inputs before returning to the model // to prevent prompt injection vulnerabilities. if (name == null || name.length() > 50 || !name.matches( "^[a-zA-Z0-9 ]+$" )) { throw new MCPException ( "Invalid name provided" ); } return "Hello, " + name + "!" ; } } To deploy an MCP Server: Extend org.tinystruct.mcp.MCPServer . Override init() and register your tools using this.registerTool() . The framework automatically scans and maps the @Action methods. import org.tinystruct.mcp.MCPServer; public class MyMCPServer extends MCPServer { @Override public void init () { super .init(); this .registerTool( new MyCustomTool ()); } @Override public String version () { return "1.0.0" ; } } Run the server via the dispatcher: bin/dispatcher start --import org.tinystruct.system.HttpServer --import com.example.MyMCPServer Configuration Settings are managed in src/main/resources/application.properties . # Database driver=org.h2.Driver database.url=jdbc:h2:~/mydb database.user=sa database.password= # Server default.home.page=hello server.port=8080 # Locale default.language=en_US # Session (Redis for clustered environments) # default.session.repository=org.tinystruct.http.RedisSessionRepository # redis.host=127.0.0.1 # redis.port=6379 Access config values in your application: String port = this .getConfiguration( "server.port" ); Red Flags & Anti-patterns Symptom Correct Pattern Importing com.google.gson or com.fasterxml.jackson Use org.tinystruct.data.component.Builder / Builders . Using List<Builder> for JSON arrays Use Builders to avoid generic type erasure issues. ApplicationRuntimeException: template not found Call setTemplateRequired(false) in init() for API-only apps. Annotating private methods with @Action Actions must be public to be registered by the framework. Hardcoding main(String[] args) in apps Use bin/dispatcher as the entry point for all modules. Manual ActionRegistry registration Prefer the @Action annotation for automatic discovery. Action not found at runtime Ensure class is imported via --import or listed in application.properties . CLI arg not visible Pass with --key value ; access via getContext().getAttribute("--key") . Two methods same path, wrong one fires Set explicit mode (e.g., HTTP_GET vs HTTP_POST ) to disambiguate. Best Practices Granular Applications : Break logic into smaller, focused applications rather than one monolithic class. Setup in init() : Leverage init() for setup (config, DB) rather than the constructor. Do NOT call setAction() — use @Action annotation. Mode Awareness : Use the Mode parameter in @Action to restrict sensitive operations to CLI only or specific HTTP methods. Context over Params : For optional CLI flags, use getContext().getAttribute("--flag") rather than adding parameters to the method signature. Asynchronous Events : For heavy tasks triggered by events, use CompletableFuture.runAsync() inside the event handler. Technical Reference Detailed guides are available in the references/ directory: Architecture & Config — Abstractions, Package Map, Properties Routing & @Action — Annotation details, Modes, Parameters Data Handling — Builder, Builders, JSON serialization & parsing Database Persistence — AbstractData POJOs, CRUD, mapping XML, POJO generation System & Usage — Context, Sessions, SSE, File Uploads, Events, Networking Testing Patterns — JUnit 5 unit and HTTP integration testing Reference Source Files (Internal) src/main/java/org/tinystruct/AbstractApplication.java — Core base class with lifecycle hooks src/main/java/org/tinystruct/system/annotation/Action.java — Annotation & Modes src/main/java/org/tinystruct/application/ActionRegistry.java — Routing Engine src/main/java/org/tinystruct/data/component/Builder.java — JSON object serializer src/main/java/org/tinystruct/data/component/Builders.java — JSON array serializer src/main/java/org/tinystruct/data/component/AbstractData.java — Base POJO class with CRUD src/main/java/org/tinystruct/data/Mapping.java — Mapping XML parser src/main/java/org/tinystruct/data/tools/MySQLGenerator.java — POJO generator reference src/main/java/org/tinystruct/data/component/FieldType.java — SQL-to-Java type mappings src/main/java/org/tinystruct/data/component/Condition.java — Fluent SQL query builder src/main/java/org/tinystruct/http/SSEPushManager.java — SSE connection management src/test/java/org/tinystruct/application/ActionRegistryTest.java — Registry test examples src/test/java/org/tinystruct/system/HttpServerHttpModeTest.java — HTTP integration test patterns