feat: implement caldav search

vendor/github.com/dolanor/caldav-go/caldav/request.go

@@ -0,0 +1,56 @@
+package caldav
+
+import (
+	"bytes"
+	"github.com/dolanor/caldav-go/http"
+	"github.com/dolanor/caldav-go/icalendar"
+	"github.com/dolanor/caldav-go/utils"
+	"github.com/dolanor/caldav-go/webdav"
+	"io"
+	"io/ioutil"
+	"log"
+	"strings"
+)
+
+var _ = log.Print
+
+// an CalDAV request object
+type Request webdav.Request
+
+// downcasts the request to the WebDAV interface
+func (r *Request) WebDAV() *webdav.Request {
+	return (*webdav.Request)(r)
+}
+
+// creates a new CalDAV request object
+func NewRequest(method string, urlstr string, icaldata ...interface{}) (*Request, error) {
+	if buffer, err := icalToReadCloser(icaldata...); err != nil {
+		return nil, utils.NewError(NewRequest, "unable to encode icalendar data", icaldata, err)
+	} else if r, err := http.NewRequest(method, urlstr, buffer); err != nil {
+		return nil, utils.NewError(NewRequest, "unable to create request", urlstr, err)
+	} else {
+		if buffer != nil {
+			// set the content type to XML if we have a body
+			r.Native().Header.Set("Content-Type", "text/calendar; charset=UTF-8")
+		}
+		return (*Request)(r), nil
+	}
+}
+
+func icalToReadCloser(icaldata ...interface{}) (io.ReadCloser, error) {
+	var buffer []string
+	for _, icaldatum := range icaldata {
+		if encoded, err := icalendar.Marshal(icaldatum); err != nil {
+			return nil, utils.NewError(icalToReadCloser, "unable to encode as icalendar data", icaldatum, err)
+		} else {
+			//			log.Printf("OUT: %+v", encoded)
+			buffer = append(buffer, encoded)
+		}
+	}
+	if len(buffer) > 0 {
+		var encoded = strings.Join(buffer, "\n")
+		return ioutil.NopCloser(bytes.NewBuffer([]byte(encoded))), nil
+	} else {
+		return nil, nil
+	}
+}