More granular errors, start get_multiple

sru/almasru.py

@@ -82,19 +82,52 @@ class RecordRetriever:
         :raises SruDiagnostics: if SRU returns an error
         """
 
-        startrecord = '0'
-
+        startrecord = 0
         sru_url = self._create_url(alma_query, startrecord)
         sru_xml = self._response_to_xml(sru_url)
 
-        self._raise_errors_unique_record(sru_xml)
+        num_recs = sru_xml.find("srw:numberOfRecords", self.namespaces)
+        self._raise_error_unique(num_recs)
+        self._raise_error_no_match(num_recs)
+        self._raise_error_sru(sru_xml)
 
         xml_list = self._extract_marc_xml(sru_xml)
         return xml_list[0]
 
-    def _create_url(self, alma_query: str, startrecord: str) -> str:
+    def get_multiple(self, alma_query: str) -> list:
+        """Return one MARC XML record for a specific query.
+
+        :param alma_query: URI-parameter query for SRU request
+        :return: XML as list of etree-Elements
+        :rtype list
+        :raises NoRecord: if no record was returned by SRU
+        :raises SruDiagnostics: if SRU returns an error
+        """
+
+        startrecord = 0
+        sru_url = self._create_url(alma_query, startrecord)
+        sru_xml = self._response_to_xml(sru_url)
+
+        num_recs = sru_xml.find("srw:numberOfRecords", self.namespaces)
+        self._raise_error_no_match(num_recs)
+        self._raise_error_sru(sru_xml)
+
+        num_pages = num_recs//10
+
+        xml_list = self._extract_marc_xml(sru_xml)
+
+        for i in range(num_pages):
+
+            startrecord = i*10
+            sru_url = self._create_url(alma_query, startrecord)
+            sru_xml = self._response_to_xml(sru_url)
+            xml_list.append(self._extract_marc_xml(sru_xml))
+
+        return xml_list
+
+    def _create_url(self, alma_query: str, startrecord: int) -> str:
 
-        self.url_query['startRecord'] = startrecord
+        self.url_query['startRecord'] = str(startrecord)
         self.url_query['maximumRecords'] = '1'
         self.url_query['query'] = alma_query
         url_query_string = parse.urlencode(self.url_query)
@@ -102,27 +135,30 @@ class RecordRetriever:
 
         return sru_url
 
-    def _response_to_xml(self, sru_url):
+    @staticmethod
+    def _response_to_xml(url):
 
-        response = request.urlopen(sru_url).read()
-        sru_xml = fromstring(response)
+        response = request.urlopen(url).read()
+        xml = fromstring(response)
 
-        return sru_xml
+        return xml
 
-    def _raise_errors_unique_record(self, sru_xml: Element):
-
-        num_recs = sru_xml.find("srw:numberOfRecords", self.namespaces)
+    @staticmethod
+    def _raise_error_unique(num_recs: Element):
 
         if (num_recs is not None and
-                num_recs.text == '0'):
-            raise NoRecord('No matching records found!')
-
-        elif (num_recs is not None and
                 num_recs.text > '1'):
             raise MultiRecord('More than one record found'
                               'while exactly one was expected!')
 
-    def _raise_errors_sru(self, sru_xml: Element):
+    @staticmethod
+    def _raise_error_no_match(num_recs: Element):
+
+        if (num_recs is not None and
+                num_recs.text == '0'):
+            raise NoRecord('No matching records found!')
+
+    def _raise_error_sru(self, sru_xml: Element):
 
         if sru_xml.find("srw:diagnostics", self.namespaces):
             xpath = "srw:diagnostics/diag:diagnostic/diag:message"