Add JSON Support

.gitignore

@@ -22,4 +22,4 @@ __pycache__
 .mcp.json
 .claude
 CLAUDE.md
-.kli/**
+*.xml

README.md

@@ -58,7 +58,7 @@ Once you have a Mojo project set up locally,
 
    ```toml
    [dependencies]
-   lightbug_http = ">=0.26.1.2,<0.26.2"
+   lightbug_http = ">=0.26.2.0,<0.26.3"
    ```
 
 3. Run `pixi install` at the root of your project, where `pixi.toml` is located
@@ -151,6 +151,33 @@ struct ExampleRouter(HTTPService):
 
 We plan to add more advanced routing functionality in a future library called `lightbug_api`, see [Roadmap](#roadmap) for more details.
 
+### JSON
+
+Use `json_decode[T]` to deserialize a request body into a typed struct, and `Json(value)` to return a JSON response:
+
+```mojo
+from lightbug_http import OK, HTTPRequest, HTTPResponse, HTTPService
+from lightbug_http.http.json import Json, json_decode
+
+@fieldwise_init
+struct GreetRequest(Movable, Defaultable):
+    var name: String
+    fn __init__(out self): self.name = ""
+
+@fieldwise_init
+struct GreetResponse(Movable, Defaultable):
+    var message: String
+    fn __init__(out self): self.message = ""
+
+@fieldwise_init
+struct JsonService(HTTPService):
+    fn func(mut self, req: HTTPRequest) raises -> HTTPResponse:
+        var body = json_decode[GreetRequest](req)
+        return OK(Json(GreetResponse(String("Hello, ", body.name, "!"))))
+```
+
+JSON support is powered by [emberjson](https://github.com/bgreni/EmberJson).
+
 
 <p align="right">(<a href="#readme-top">back to top</a>)</p>
 
@@ -190,7 +217,7 @@ Check out the examples directory for more example services built with Lightbug,
 
 We're working on support for the following (contributors welcome!):
 
- - [ ] [JSON support](https://github.com/saviorand/lightbug_http/issues/4)
+ - [x] [JSON support](https://github.com/saviorand/lightbug_http/issues/4)
  - [ ] Complete HTTP/1.x support compliant with RFC 9110/9112 specs (see issues)
  - [ ] [SSL/HTTPS support](https://github.com/saviorand/lightbug_http/issues/20)
  - [ ] [Multiple simultaneous connections](https://github.com/saviorand/lightbug_http/issues/5), [parallelization and performance optimizations](https://github.com/saviorand/lightbug_http/issues/6)

examples/echo_server/pixi.toml

@@ -11,7 +11,7 @@ server = "mojo run server.mojo"
 client = "mojo run client.mojo"
 
 [dependencies]
-mojo = ">=0.26.1.0,<0.26.2.0"
+mojo = ">=0.26.2.0,<0.26.3"
 curl_wrapper = { git = "https://github.com/thatstoasty/mojo-curl.git", branch = "main", subdirectory = "shim" }
 floki = ">=0.1.0,<0.2"
-lightbug_http = ">=0.26.1.2,<0.26.2.0"
+lightbug_http = ">=0.26.2.0,<0.26.3"

examples/json_service/README.md

@@ -0,0 +1,18 @@
+# JSON Service
+
+A simple JSON API example using `lightbug_http`. The server accepts a POST request with a JSON body and returns a JSON response.
+
+To run the server:
+
+```bash
+pixi run server
+```
+
+Then send a request:
+
+```bash
+curl -X POST http://localhost:8080/greet \
+  -H "Content-Type: application/json" \
+  -d '{"name": "Alice"}'
+# {"message":"Hello, Alice!"}
+```

examples/json_service/pixi.toml

@@ -0,0 +1,13 @@
+[workspace]
+channels = ["https://conda.modular.com/max", "https://repo.prefix.dev/modular-community", "https://repo.prefix.dev/mojo-community", "conda-forge"]
+name = "json_service"
+platforms = ["osx-arm64", "linux-64", "linux-aarch64"]
+version = "0.1.0"
+preview = ["pixi-build"]
+
+[tasks]
+server = "mojo run server.mojo"
+
+[dependencies]
+mojo = ">=2.0,<0.26.3"
+lightbug_http = ">=0.26.2.0,<0.26.3"

examples/json_service/server.mojo

@@ -0,0 +1,34 @@
+from lightbug_http import OK, NotFound, HTTPRequest, HTTPResponse, HTTPService, Server
+from lightbug_http.http.json import Json, json_decode
+
+
+@fieldwise_init
+struct GreetRequest(Movable, Defaultable):
+    var name: String
+
+    fn __init__(out self):
+        self.name = ""
+
+
+@fieldwise_init
+struct GreetResponse(Movable, Defaultable):
+    var message: String
+
+    fn __init__(out self):
+        self.message = ""
+
+
+@fieldwise_init
+struct JsonService(HTTPService):
+    fn func(mut self, req: HTTPRequest) raises -> HTTPResponse:
+        if req.uri.path == "/greet":
+            var body = json_decode[GreetRequest](req)
+            var response = GreetResponse(String("Hello, ", body.name, "!"))
+            return OK(Json(response))
+        return NotFound(req.uri.path)
+
+
+fn main() raises:
+    var server = Server()
+    var handler = JsonService()
+    server.listen_and_serve("localhost:8080", handler)

lightbug.mojo

@@ -0,0 +1,13 @@
+from lightbug_http import Welcome
+from lightbug_http.server import Server
+from std.os.env import getenv
+
+
+fn main() raises:
+    var server = Server()
+    var handler = Welcome()
+
+    var host = getenv("DEFAULT_SERVER_HOST", "localhost")
+    var port = getenv("DEFAULT_SERVER_PORT", "8080")
+
+    server.listen_and_serve(host + ":" + port, handler)

lightbug_http/__init__.mojo

@@ -4,4 +4,4 @@ from lightbug_http.service import Counter, HTTPService, Welcome
 from lightbug_http.uri import URI
 
 from lightbug_http.cookie import Cookie, RequestCookieJar, ResponseCookieJar
-from lightbug_http.http import OK, HTTPRequest, HTTPResponse, NotFound, SeeOther, StatusCode
+from lightbug_http.http import OK, HTTPRequest, HTTPResponse, NotFound, SeeOther, StatusCode, Json, json_decode, JsonSerializable, JsonDeserializable