Feature/client

Makefile

@@ -1,6 +1,10 @@
 ROOT_DIR := $(dir $(realpath $(lastword $(MAKEFILE_LIST))))
 
-run:
+build:
+	go build -o $(ROOT_DIR)/bin/facilitator $(ROOT_DIR)/cmd/facilitator
+	go build -o $(ROOT_DIR)/bin/client $(ROOT_DIR)/cmd/client
+
+run-facilitator:
 	go run $(ROOT_DIR)/cmd/facilitator \
 		--config $(ROOT_DIR)/config.toml
 

README.md

@@ -14,11 +14,35 @@
 | Sui       | 🚧 Planned        |                               |
 | Tron      | 🚧 Planned        |                               |
 
-# How to run
+## How to run
+
+### Build binary
+```bash
+make build
+```
+
+### Run x402-facilitator using docker
 ```bash
 docker compose up
 ```
 
+### Run x402-client
+```
+Usage:
+  client [flags]
+
+Flags:
+  -A, --amount string    Amount to send
+  -F, --from string      Sender address
+  -h, --help             help for x402-client
+  -n, --network string   Blockchain network to use (default "base-sepolia")
+  -P, --privkey string   Sender private key
+  -s, --scheme string    Scheme to use (default "evm")
+  -T, --to string        Recipient address
+  -t, --token string     token contract for sending (default "USDC")
+  -u, --url string       Base URL of the facilitator server (default "http://localhost:9090")
+```
+
 ## Api Specification
 After starting the service, open your browser to:
 ```

api/client/client.go

@@ -0,0 +1,136 @@
+package client
+
+import (
+	"bytes"
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+
+	"github.com/rabbitprincess/x402-facilitator/types"
+)
+
+type Client struct {
+	BaseURL          *url.URL
+	HTTPClient       *http.Client
+	CreateAuthHeader func() (map[string]map[string]string, error)
+}
+
+func NewClient(baseURL string) (*Client, error) {
+	parsed, err := url.Parse(baseURL)
+	if err != nil {
+		return nil, fmt.Errorf("invalid base URL: %w", err)
+	}
+	return &Client{
+		BaseURL:    parsed,
+		HTTPClient: http.DefaultClient,
+	}, nil
+}
+
+// Supported fetches the list of supported schemes.
+func (c *Client) Supported(ctx context.Context) ([]types.SupportedKind, error) {
+	var result []types.SupportedKind
+	if err := c.doRequest(ctx, http.MethodGet, "/supported", nil, "", &result); err != nil {
+		return nil, err
+	}
+	return result, nil
+}
+
+func (c *Client) Verify(ctx context.Context, payload *types.PaymentPayload, req *types.PaymentRequirements) (*types.PaymentVerifyResponse, error) {
+	payloadJson, err := json.Marshal(payload)
+	if err != nil {
+		return nil, fmt.Errorf("marshal payment payload: %w", err)
+	}
+	header := base64.StdEncoding.EncodeToString(payloadJson)
+
+	body := types.PaymentVerifyRequest{
+		X402Version:         int(types.X402VersionV1),
+		PaymentHeader:       header,
+		PaymentRequirements: *req,
+	}
+
+	var resp types.PaymentVerifyResponse
+	if err := c.doRequest(ctx, http.MethodPost, "/verify", body, "verify", &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+// Settle sends a payment settlement request.
+func (c *Client) Settle(ctx context.Context, payload *types.PaymentPayload, req *types.PaymentRequirements) (*types.PaymentSettleResponse, error) {
+	payloadJson, err := json.Marshal(payload)
+	if err != nil {
+		return nil, fmt.Errorf("marshal payment payload: %w", err)
+	}
+	header := base64.StdEncoding.EncodeToString(payloadJson)
+
+	body := types.PaymentSettleRequest{
+		X402Version:         int(types.X402VersionV1),
+		PaymentHeader:       header,
+		PaymentRequirements: *req,
+	}
+
+	var resp types.PaymentSettleResponse
+	if err := c.doRequest(ctx, http.MethodPost, "/settle", body, "settle", &resp); err != nil {
+		return nil, err
+	}
+	return &resp, nil
+}
+
+func (c *Client) doRequest(ctx context.Context, method, path string, body any, authKey string, out any) error {
+	// Build URL
+	u := c.BaseURL.ResolveReference(&url.URL{Path: path})
+
+	// Prepare body
+	var reader io.Reader
+	if body != nil {
+		payload, err := json.Marshal(body)
+		if err != nil {
+			return fmt.Errorf("marshal request body: %w", err)
+		}
+		reader = bytes.NewReader(payload)
+	}
+
+	// Create HTTP request
+	req, err := http.NewRequestWithContext(ctx, method, u.String(), reader)
+	if err != nil {
+		return err
+	}
+	if body != nil {
+		req.Header.Set("Content-Type", "application/json")
+	}
+
+	if authKey != "" && c.CreateAuthHeader != nil {
+		hdrs, err := c.CreateAuthHeader()
+		if err != nil {
+			return fmt.Errorf("create auth headers: %w", err)
+		}
+		if section, ok := hdrs[authKey]; ok {
+			for k, v := range section {
+				req.Header.Set(k, v)
+			}
+		}
+	}
+
+	// Execute
+	resp, err := c.HTTPClient.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		data, _ := io.ReadAll(resp.Body)
+		return fmt.Errorf("%s %s failed: status %d, body: %s", method, path, resp.StatusCode, string(data))
+	}
+
+	if out != nil {
+		if err := json.NewDecoder(resp.Body).Decode(out); err != nil {
+			return fmt.Errorf("decode %s response: %w", path, err)
+		}
+	}
+	return nil
+}

api/server.go

@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"net/http"
 
-	"github.com/go-playground/validator/v10"
 	"github.com/labstack/echo/v4"
 	echomiddleware "github.com/labstack/echo/v4/middleware"
 	_ "github.com/rabbitprincess/x402-facilitator/api/swagger"
@@ -19,9 +18,6 @@ import (
 // @title        x402 Facilitator API
 // @version      1.0
 // @description  API server for x402 payment facilitator
-// @host         localhost:8080
-// @BasePath     /
-// @schemes      http
 type server struct {
 	*echo.Echo
 	facilitator facilitator.Facilitator
@@ -51,10 +47,6 @@ func NewServer(facilitator facilitator.Facilitator) *server {
 	return s
 }
 
-var (
-	validate = validator.New(validator.WithRequiredStructEnabled())
-)
-
 // Settle handles payment settlement requests
 // @Summary      Settle payment
 // @Description  Settle a payment using the facilitator
@@ -73,9 +65,7 @@ func (s *server) Settle(c echo.Context) error {
 	if err := json.NewDecoder(c.Request().Body).Decode(requirement); err != nil {
 		return echo.NewHTTPError(http.StatusBadRequest, "Received malformed settlement request")
 	}
-	if err := validate.Struct(requirement); err != nil {
-		return echo.NewHTTPError(http.StatusBadRequest, "Received invalid settlement request")
-	}
+
 	payment := &types.PaymentPayload{}
 	paymentDecoded, err := base64.StdEncoding.DecodeString(requirement.PaymentHeader)
 	if err != nil {
@@ -84,9 +74,7 @@ func (s *server) Settle(c echo.Context) error {
 	if err := json.Unmarshal(paymentDecoded, payment); err != nil {
 		return echo.NewHTTPError(http.StatusBadRequest, "Received malformed Payment header")
 	}
-	if err := validate.Struct(payment); err != nil {
-		return echo.NewHTTPError(http.StatusBadRequest, "Received invalid Payment header")
-	}
+
 	settle, err := s.facilitator.Settle(ctx, payment, &requirement.PaymentRequirements)
 	if err != nil {
 		return echo.NewHTTPError(http.StatusInternalServerError, err.Error())
@@ -113,9 +101,6 @@ func (s *server) Verify(c echo.Context) error {
 	if err := json.NewDecoder(c.Request().Body).Decode(requirement); err != nil {
 		return echo.NewHTTPError(http.StatusBadRequest, "Received malformed payment requirements")
 	}
-	if err := validate.Struct(requirement); err != nil {
-		return echo.NewHTTPError(http.StatusBadRequest, "Received invalid payment requirements")
-	}
 
 	// validate payment payload
 	payment := &types.PaymentPayload{}
@@ -126,9 +111,6 @@ func (s *server) Verify(c echo.Context) error {
 	if err := json.Unmarshal(paymentDecoded, payment); err != nil {
 		return echo.NewHTTPError(http.StatusBadRequest, "Received malformed Payment header")
 	}
-	if err := validate.Struct(payment); err != nil {
-		return echo.NewHTTPError(http.StatusBadRequest, "Received invalid Payment header")
-	}
 
 	verified, err := s.facilitator.Verify(ctx, payment, &requirement.PaymentRequirements)
 	if err != nil {

api/swagger/docs.go

@@ -294,9 +294,9 @@ const docTemplate = `{
 // SwaggerInfo holds exported Swagger Info so clients can modify it
 var SwaggerInfo = &swag.Spec{
 	Version:          "1.0",
-	Host:             "localhost:8080",
-	BasePath:         "/",
-	Schemes:          []string{"http"},
+	Host:             "",
+	BasePath:         "",
+	Schemes:          []string{},
 	Title:            "x402 Facilitator API",
 	Description:      "API server for x402 payment facilitator",
 	InfoInstanceName: "swagger",

api/swagger/swagger.json

@@ -1,16 +1,11 @@
 {
-    "schemes": [
-        "http"
-    ],
     "swagger": "2.0",
     "info": {
         "description": "API server for x402 payment facilitator",
         "title": "x402 Facilitator API",
         "contact": {},
         "version": "1.0"
     },
-    "host": "localhost:8080",
-    "basePath": "/",
     "paths": {
         "/settle": {
             "post": {

api/swagger/swagger.yaml

@@ -1,4 +1,3 @@
-basePath: /
 definitions:
   echo.HTTPError:
     properties:
@@ -106,7 +105,6 @@ definitions:
       scheme:
         type: string
     type: object
-host: localhost:8080
 info:
   contact: {}
   description: API server for x402 payment facilitator
@@ -192,6 +190,4 @@ paths:
       summary: Verify payment
       tags:
       - payments
-schemes:
-- http
 swagger: "2.0"