From 8f6f9326de5bbeba2b1bdcf93f360d9f179fb831 Mon Sep 17 00:00:00 2001
From: fangdingjun <fangdingjun@gmail.com>
Date: Sat, 20 Oct 2018 17:29:50 +0800
Subject: [PATCH] v0.0.1

---
 README.md       |  35 ++++++++++++++
 jsonrpc.go      | 120 ++++++++++++++++++++++++++++++++++++++++++++++++
 jsonrpc_test.go |  44 ++++++++++++++++++
 3 files changed, 199 insertions(+)
 create mode 100644 README.md
 create mode 100644 jsonrpc.go
 create mode 100644 jsonrpc_test.go

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..c1286b4
--- /dev/null
+++ b/README.md
@@ -0,0 +1,35 @@
+jsonrpc
+=======
+
+simple jsonrpc 2.0 client
+
+
+usage
+====
+example
+
+    package main
+
+    import (
+        "github.com/fangdingjun/jsonrpc"
+        "log"
+    )
+
+    type result struct{
+        R1 string `json:"r1"`
+        R2 string `json:"r2"`
+    }
+
+    func main(){
+        client, _ := jsonrpc.NewClient("http://admin:123@127.0.0.1:2312/jsonrpc")
+        // client.Debug = true
+        // client.HTTPClient = &http.Client{...}
+
+        var ret result
+        var args = []interface{}{1, "a", 2}
+        err := client.Call("some_method", args, &ret)
+        if err != nil{
+            log.Fatal(err)
+        }
+        log.Println(ret)
+    }
diff --git a/jsonrpc.go b/jsonrpc.go
new file mode 100644
index 0000000..bac9ba0
--- /dev/null
+++ b/jsonrpc.go
@@ -0,0 +1,120 @@
+package jsonrpc
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+)
+
+// Client json rpc client
+type Client struct {
+	// URL is remote url, ex http://username:password@192.168.1.3:1001/jsonrpc
+	URL string
+	// http client, default is http.DefaultClient
+	HTTPClient *http.Client
+	id         uint64
+	// Debug set to true, log the send/recevied http data
+	Debug bool
+}
+
+type request struct {
+	Version string      `json:"jsonrpc"`
+	Method  string      `json:"method"`
+	Params  interface{} `json:"params"`
+	ID      uint64      `json:"id"`
+}
+
+type response struct {
+	Version string          `json:"jsonrpc"`
+	Result  json.RawMessage `json:"result"`
+	Error   *errorObj       `json:"error"`
+	ID      uint64          `json:"id"`
+}
+
+type errorObj struct {
+	Code    int         `json:"code"`
+	Message string      `json:"message"`
+	Data    interface{} `json:"data"`
+}
+
+// NewClient create a new jsonrpc client
+func NewClient(url string) (*Client, error) {
+	return &Client{URL: url, HTTPClient: http.DefaultClient}, nil
+}
+
+func (c *Client) nextID() uint64 {
+	c.id++
+	return c.id
+}
+
+// Call invoke a method with args and return reply
+func (c *Client) Call(method string, args interface{}, reply interface{}) error {
+	client := c.HTTPClient
+	if client == nil {
+		client = http.DefaultClient
+	}
+
+	if args == nil {
+		args = []string{}
+	}
+
+	r := &request{
+		Version: "2.0",
+		Method:  method,
+		Params:  args,
+		ID:      c.nextID(),
+	}
+
+	data, err := json.Marshal(r)
+	if err != nil {
+		return err
+	}
+
+	if c.Debug {
+		log.Println("send", string(data))
+	}
+
+	body := bytes.NewBuffer(data)
+
+	req, err := http.NewRequest("POST", c.URL, body)
+	if err != nil {
+		return err
+	}
+
+	req.Header.Set("Content-Type", "application/json")
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return err
+	}
+
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("http error: %s", resp.Status)
+	}
+
+	data, err = ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return err
+	}
+
+	if c.Debug {
+		log.Println("recevied", string(data))
+	}
+
+	var res response
+
+	if err = json.Unmarshal(data, &res); err != nil {
+		return err
+	}
+
+	if res.Error != nil {
+		return fmt.Errorf("%d: %s", res.Error.Code, res.Error.Message)
+	}
+
+	return json.Unmarshal(res.Result, &reply)
+}
diff --git a/jsonrpc_test.go b/jsonrpc_test.go
new file mode 100644
index 0000000..a976f8a
--- /dev/null
+++ b/jsonrpc_test.go
@@ -0,0 +1,44 @@
+package jsonrpc
+
+import (
+	"log"
+	"testing"
+)
+
+func TestCall(t *testing.T) {
+	url := "http://192.168.56.101:8542/"
+	c, _ := NewClient(url)
+	c.Debug = true
+	var ret interface{}
+	err := c.Call("eth_getBalance", []string{"0x00CB25f6fD16a52e24eDd2c8fd62071dc29A035c", "latest"}, &ret)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	log.Printf("result: %+v", ret)
+
+	url = "http://admin2:123@192.168.56.101:19011/"
+
+	c, _ = NewClient(url)
+	c.Debug = true
+
+	err = c.Call("getbalance", []string{}, &ret)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+
+	log.Printf("result: %+v", ret)
+
+	if err = c.Call("fuck", []string{}, &ret); err == nil {
+		t.Errorf("expected error, got nil")
+		return
+	}
+	log.Println("got", err)
+
+	if err = c.Call("listreceivedbyaddress", []interface{}{0, false}, &ret); err != nil {
+		t.Error(err)
+		return
+	}
+	log.Printf("result: %+v", ret)
+}