Added fetch script for UK Gov FindATender service which is based on OCDS (with issues...)

internal/findATender/dateRepair.go

@@ -0,0 +1,59 @@
+/*
+Copyright © 2026 Craig Williams <craig@avsdev.uk>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+package findATender
+
+import (
+	"bufio"
+	"bytes"
+	"io"
+	"regexp"
+)
+
+// Global regex to identify and catch date-only fields
+var invalidDateRegex = regexp.MustCompile(`:\s*"(\d{4}-\d{2}-\d{2})"\s*([,}\s])`)
+var invalidPublishedDateRegex = regexp.MustCompile(`"publishedDate":\s*""`)
+
+// The UK Government FindATender service doesn't strictly follow OCDS date
+// format. Sometimes it provides dates only, sometimes it sends empty strings
+// instead of nulls.
+type FindATenderStreamCleaner struct {
+	reader *bufio.Reader
+	buffer bytes.Buffer
+}
+
+func NewOCDSStreamCleaner(r io.Reader) *FindATenderStreamCleaner {
+	return &FindATenderStreamCleaner{reader: bufio.NewReader(r)}
+}
+
+func (sc *FindATenderStreamCleaner) Read(p []byte) (int, error) {
+	if sc.buffer.Len() == 0 {
+		line, err := sc.reader.ReadBytes('\n')
+		if len(line) > 0 {
+			// Convert "2026-11-16" -> "2026-11-16T00:00:00Z"
+			line = invalidDateRegex.ReplaceAll(line, []byte(`:"$1T00:00:00Z"`))
+			// Convert {publishedDate:""} -> "{publishedDate:null}"
+			line = invalidPublishedDateRegex.ReplaceAll(line, []byte(`"publishedDate":null`))
+			sc.buffer.Write(line)
+		}
+		if err != nil {
+			if sc.buffer.Len() == 0 {
+				return 0, err
+			}
+		}
+	}
+	return sc.buffer.Read(p)
+}