Reconstruct KeePassGO repository

webdav/client.go

@@ -0,0 +1,93 @@
+package webdav
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+)
+
+var ErrConflict = errors.New("webdav conflict")
+
+type Version struct {
+	ETag string
+}
+
+type Client struct {
+	HTTPClient *http.Client
+	BaseURL    string
+	Username   string
+	Password   string
+}
+
+func (c Client) Open(path string) ([]byte, Version, error) {
+	req, err := http.NewRequest(http.MethodGet, c.url(path), nil)
+	if err != nil {
+		return nil, Version{}, fmt.Errorf("build GET request: %w", err)
+	}
+	c.applyAuth(req)
+
+	resp, err := c.httpClient().Do(req)
+	if err != nil {
+		return nil, Version{}, fmt.Errorf("GET %s: %w", path, err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, Version{}, fmt.Errorf("GET %s: unexpected status %d", path, resp.StatusCode)
+	}
+
+	content, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, Version{}, fmt.Errorf("read %s: %w", path, err)
+	}
+
+	return content, Version{ETag: resp.Header.Get("ETag")}, nil
+}
+
+func (c Client) Save(path string, content io.Reader, version Version) (Version, error) {
+	req, err := http.NewRequest(http.MethodPut, c.url(path), content)
+	if err != nil {
+		return Version{}, fmt.Errorf("build PUT request: %w", err)
+	}
+	c.applyAuth(req)
+	if version.ETag != "" {
+		req.Header.Set("If-Match", version.ETag)
+	}
+
+	resp, err := c.httpClient().Do(req)
+	if err != nil {
+		return Version{}, fmt.Errorf("PUT %s: %w", path, err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode == http.StatusPreconditionFailed {
+		return Version{}, ErrConflict
+	}
+	if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusCreated && resp.StatusCode != http.StatusNoContent {
+		return Version{}, fmt.Errorf("PUT %s: unexpected status %d", path, resp.StatusCode)
+	}
+
+	return Version{ETag: resp.Header.Get("ETag")}, nil
+}
+
+func (c Client) httpClient() *http.Client {
+	if c.HTTPClient != nil {
+		return c.HTTPClient
+	}
+	return http.DefaultClient
+}
+
+func (c Client) applyAuth(req *http.Request) {
+	if c.Username == "" && c.Password == "" {
+		return
+	}
+	req.SetBasicAuth(c.Username, c.Password)
+}
+
+func (c Client) url(path string) string {
+	base := strings.TrimRight(c.BaseURL, "/")
+	path = strings.TrimLeft(path, "/")
+	return base + "/" + path
+}