first commit

pkg/gitea/rest.go

@@ -0,0 +1,184 @@
+package gitea
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"sync"
+	"time"
+
+	mcpContext "gitea.com/gitea/gitea-mcp/pkg/context"
+	"gitea.com/gitea/gitea-mcp/pkg/flag"
+)
+
+const (
+	httpClientTimeout  = 60 * time.Second
+	errBodySnippetSize = 8192
+)
+
+type HTTPError struct {
+	StatusCode int
+	Body       string
+}
+
+func (e *HTTPError) Error() string {
+	if e.Body == "" {
+		return fmt.Sprintf("request failed with status %d", e.StatusCode)
+	}
+	return fmt.Sprintf("request failed with status %d: %s", e.StatusCode, e.Body)
+}
+
+func tokenFromContext(ctx context.Context) string {
+	if ctx != nil {
+		if token, ok := ctx.Value(mcpContext.TokenContextKey).(string); ok && token != "" {
+			return token
+		}
+	}
+	return flag.Token
+}
+
+var (
+	restClientOnce sync.Once
+	restClient     *http.Client
+)
+
+func restHTTPClient() *http.Client {
+	restClientOnce.Do(func() {
+		restClient = &http.Client{
+			Transport:     sharedTransport(),
+			Timeout:       httpClientTimeout,
+			CheckRedirect: checkRedirect,
+		}
+	})
+	return restClient
+}
+
+func buildAPIURL(path string, query url.Values) (string, error) {
+	host := strings.TrimRight(flag.Host, "/")
+	if host == "" {
+		return "", errors.New("gitea host is empty")
+	}
+	p := strings.TrimLeft(path, "/")
+	u, err := url.Parse(fmt.Sprintf("%s/api/v1/%s", host, p))
+	if err != nil {
+		return "", err
+	}
+	if query != nil {
+		u.RawQuery = query.Encode()
+	}
+	return u.String(), nil
+}
+
+// DoJSON performs an API request and decodes a JSON response into respOut (if non-nil).
+// It returns the HTTP status code.
+func DoJSON(ctx context.Context, method, path string, query url.Values, body, respOut any) (int, error) {
+	var bodyReader io.Reader
+	if body != nil {
+		b, err := json.Marshal(body)
+		if err != nil {
+			return 0, fmt.Errorf("marshal request body: %w", err)
+		}
+		bodyReader = bytes.NewReader(b)
+	}
+
+	u, err := buildAPIURL(path, query)
+	if err != nil {
+		return 0, err
+	}
+	req, err := http.NewRequestWithContext(ctx, method, u, bodyReader)
+	if err != nil {
+		return 0, fmt.Errorf("create request: %w", err)
+	}
+
+	token := tokenFromContext(ctx)
+	if token != "" {
+		req.Header.Set("Authorization", "token "+token)
+	}
+	req.Header.Set("Accept", "application/json")
+	if body != nil {
+		req.Header.Set("Content-Type", "application/json")
+	}
+
+	client := restHTTPClient()
+	resp, err := client.Do(req)
+	if err != nil {
+		return 0, fmt.Errorf("do request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		bodySnippet, _ := io.ReadAll(io.LimitReader(resp.Body, errBodySnippetSize))
+		return resp.StatusCode, &HTTPError{StatusCode: resp.StatusCode, Body: strings.TrimSpace(string(bodySnippet))}
+	}
+
+	if respOut == nil {
+		_, _ = io.Copy(io.Discard, resp.Body) // best-effort
+		return resp.StatusCode, nil
+	}
+
+	if err := json.NewDecoder(resp.Body).Decode(respOut); err != nil {
+		return resp.StatusCode, fmt.Errorf("decode response: %w", err)
+	}
+	return resp.StatusCode, nil
+}
+
+// DoBytes performs an API request and returns the raw response bytes.
+// It returns the HTTP status code.
+func DoBytes(ctx context.Context, method, path string, query url.Values, body any, accept string) ([]byte, int, error) {
+	var bodyReader io.Reader
+	if body != nil {
+		b, err := json.Marshal(body)
+		if err != nil {
+			return nil, 0, fmt.Errorf("marshal request body: %w", err)
+		}
+		bodyReader = bytes.NewReader(b)
+	}
+
+	u, err := buildAPIURL(path, query)
+	if err != nil {
+		return nil, 0, err
+	}
+	req, err := http.NewRequestWithContext(ctx, method, u, bodyReader)
+	if err != nil {
+		return nil, 0, fmt.Errorf("create request: %w", err)
+	}
+
+	token := tokenFromContext(ctx)
+	if token != "" {
+		req.Header.Set("Authorization", "token "+token)
+	}
+	if accept != "" {
+		req.Header.Set("Accept", accept)
+	}
+	if body != nil {
+		req.Header.Set("Content-Type", "application/json")
+	}
+
+	client := restHTTPClient()
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, 0, fmt.Errorf("do request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	respBytes, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, resp.StatusCode, fmt.Errorf("read response: %w", err)
+	}
+
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		bodySnippet := respBytes
+		if len(bodySnippet) > errBodySnippetSize {
+			bodySnippet = bodySnippet[:errBodySnippetSize]
+		}
+		return nil, resp.StatusCode, &HTTPError{StatusCode: resp.StatusCode, Body: strings.TrimSpace(string(bodySnippet))}
+	}
+
+	return respBytes, resp.StatusCode, nil
+}