feat: decode json data in response.

Author: ghosind

encoding.go

@@ -0,0 +1,10 @@
+package request
+
+import (
+"encoding/json"
+"io"
+)
+
+func decodeJson(body io.Reader, out any) error {
+return json.NewDecoder(body).Decode(out)
+}

request.go

@@ -22,12 +22,14 @@ func Request(url string, out any, opts ...RequestOptions) error {
 }
 
 func (cli *Client) Request(url string, out any, opts ...RequestOptions) error {
-_, err := cli.RequestRaw(url, opts...)
+resp, err := cli.RequestRaw(url, opts...)
 if err != nil {
 return err
 }
 
-// TODO: decode body
+if err := cli.decodeResponseBody(resp, out); err != nil {
+return err
+}
 
 return nil
 }
@@ -58,9 +60,9 @@ func (cli *Client) RequestRaw(url string, opts ...RequestOptions) (*http.Respons
 }
 
 func (cli *Client) makeRequest(url string, opt RequestOptions) (*http.Request, context.CancelFunc, error) {
-method := "GET"
-if opt.Method != "" {
-method = opt.Method
+method := opt.Method
+if method != "" {
+method = http.MethodGet
 }
 
 url, err := cli.parseURL(url, opt)

request_test.go

@@ -0,0 +1,49 @@
+package request
+
+import (
+"strings"
+"testing"
+)
+
+type ExampleProduct struct {
+Id int64
+Category string
+}
+
+type ExampleProductsSearchData struct {
+Products *[]ExampleProduct
+}
+
+func TestSimpleRequest(t *testing.T) {
+var data ExampleProduct
+
+err := Request("https://dummyjson.com/products/1", &data)
+if err != nil {
+t.Fatalf("Unexpected request error: %v", err)
+}
+
+if data.Id != 1 {
+t.Fatalf("Expect product id is 1, actually %d", data.Id)
+}
+}
+
+func TestRequestWithParameters(t *testing.T) {
+var data ExampleProductsSearchData
+
+err := Request("https://dummyjson.com/products/search", &data, RequestOptions{
+Parameters: map[string][]string{
+"q": {"laptop"},
+},
+})
+if err != nil {
+t.Fatalf("Unexpected request error: %v", err)
+}
+
+if data.Products != nil {
+for _, product := range *data.Products {
+if !strings.Contains(product.Category, "laptop") {
+t.Fatalf("Expect product category contains 'laptop', actually %s", product.Category)
+}
+}
+}
+}

response.go

@@ -0,0 +1,19 @@
+package request
+
+import (
+"net/http"
+"strings"
+)
+
+func (cli *Client) decodeResponseBody(resp *http.Response, out any) error {
+contentType := resp.Header.Get("Content-Type")
+contentType, _, _ = strings.Cut(contentType, ";") // remove parameters
+contentType = strings.TrimSpace(contentType)
+
+switch contentType {
+case "application/json":
+return decodeJson(resp.Body, out)
+}
+
+return nil
+}