1 files changed, 115 insertions, 0 deletions
diff --git a/internal/github/rest_client.go b/internal/github/rest_client.go
new file mode 100644
index 0000000..6fdd31c
--- /dev/null
+++ b/internal/github/rest_client.go
@@ -0,0 +1,115 @@
+package github
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+)
+
+type HTTPRequester interface {
+	Do(req *http.Request) (*http.Response, error)
+}
+
+type BearerAuthClient struct {
+	HTTPRequester
+	Username string
+	Password string
+}
+
+func WithBearerAuth(
+	cli HTTPRequester,
+	username, password string,
+) *BearerAuthClient {
+	return &BearerAuthClient{cli, username, password}
+}
+
+func (s *BearerAuthClient) Do(req *http.Request) (*http.Response, error) {
+	if s.Username != "" && s.Password != "" {
+		value := fmt.Sprintf("Bearer %s:%s", s.Username, s.Password)
+		req.Header.Set("Authorization", value)
+	}
+	return s.HTTPRequester.Do(req)
+}
+
+type jsonClient struct {
+	Client   HTTPRequester
+	basePath string
+}
+
+func newJSONClient(
+	cli HTTPRequester,
+	basePath string,
+) *jsonClient {
+	return &jsonClient{
+		Client:   cli,
+		basePath: basePath,
+	}
+}
+
+func newHTTPJSONReq(
+	method string,
+	url string,
+	req interface{},
+) (*http.Request, error) {
+	body := &bytes.Buffer{}
+	if req != nil {
+		buf, err := json.Marshal(req)
+		if err != nil {
+			return nil, err
+		}
+		body = bytes.NewBuffer(buf)
+	}
+	httpReq, err := http.NewRequest(method, url, body)
+	if err != nil {
+		return nil, err
+	}
+	httpReq.Header.Set("Content-Type", "application/json")
+	httpReq.Header.Set("Accept", "application/json")
+	return httpReq, nil
+}
+
+func decodeJSONResponse(httpResp *http.Response, resp interface{}) error {
+	if httpResp.StatusCode/100 != 2 {
+		return fmt.Errorf(
+			"received HTTP status code %d (%s)",
+			httpResp.StatusCode,
+			httpResp.Status,
+		)
+	}
+	if resp == nil {
+		return nil
+	}
+	err := json.NewDecoder(httpResp.Body).Decode(resp)
+	if err != nil {
+		return err
+	}
+	return err
+}
+
+func (s *jsonClient) Request(
+	method string,
+	statusCode *int,
+	path string,
+	req, resp interface{},
+) (int, error) {
+	url := fmt.Sprintf("%s/%s", s.basePath, path)
+	httpReq, err := newHTTPJSONReq(method, url, req)
+	if err != nil {
+		return 0, err
+	}
+	httpResp, err := s.Client.Do(httpReq)
+	if err != nil {
+		return 0, err
+	}
+	defer httpResp.Body.Close()
+
+	err = decodeJSONResponse(httpResp, resp)
+	if err != nil {
+		return httpResp.StatusCode, err
+	}
+	if statusCode != nil && httpResp.StatusCode != *statusCode {
+		return httpResp.StatusCode, fmt.Errorf("expected status code %d but got %d", *statusCode, httpResp.StatusCode)
+	}
+	return httpResp.StatusCode, nil
+}