add grafana package & temporary debug checks

pkg/grafana/requests.go

@@ -0,0 +1,80 @@
+package grafana
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"path"
+	"strings"
+)
+
+var DefaultHTTPClient = http.DefaultClient
+
+type Client struct {
+	baseURL   string
+	key       string
+	basicAuth bool
+	client    *http.Client
+}
+
+func NewClient(apiURL, authString string, client *http.Client) (*Client, error) {
+	basicAuth := strings.Contains(authString, ":")
+	baseURL, err := url.Parse(apiURL)
+	if err != nil {
+		return nil, err
+	}
+
+	var key string
+	if len(authString) > 0 {
+		if !basicAuth {
+			key = fmt.Sprintf("Bearer %s", authString)
+		} else {
+			parts := strings.SplitN(authString, ":", 2)
+			baseURL.User = url.UserPassword(parts[0], parts[1])
+		}
+	}
+
+	return &Client{
+		baseURL:   baseURL.String(),
+		basicAuth: basicAuth,
+		key:       key,
+		client:    client,
+	}, nil
+}
+
+func (c *Client) doRequest(ctx context.Context, method, query string, params url.Values, buf io.Reader) ([]byte, int, error) {
+	u, _ := url.Parse(c.baseURL)
+	u.Path = path.Join(u.Path, query)
+	if params != nil {
+		u.RawQuery = params.Encode()
+	}
+	req, err := http.NewRequest(method, u.String(), buf)
+	if err != nil {
+		return nil, 0, err
+	}
+	req = req.WithContext(ctx)
+	if !c.basicAuth && len(c.key) > 0 {
+		req.Header.Set("Authorization", c.key)
+	}
+	req.Header.Set("Accept", "application/json")
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("User-Agent", "grafana-backuper")
+	resp, err := c.client.Do(req)
+	if err != nil {
+		return nil, 0, err
+	}
+	data, err := io.ReadAll(resp.Body)
+	resp.Body.Close()
+	return data, resp.StatusCode, err
+}
+
+func (c *Client) get(ctx context.Context, query string, params url.Values) ([]byte, int, error) {
+	return c.doRequest(ctx, "GET", query, params, nil)
+}
+
+func (c *Client) post(ctx context.Context, query string, params url.Values, body []byte) ([]byte, int, error) {
+	return c.doRequest(ctx, "POST", query, params, bytes.NewBuffer(body))
+}