Add docsum field writer for map of struct based on values in struct

field attributes.

4 files changed, 149 insertions, 2 deletions

diff --git a/searchsummary/src/vespa/searchsummary/docsummary/CMakeLists.txt b/searchsummary/src/vespa/searchsummary/docsummary/CMakeLists.txt
index ce54e7b0ea7..dccf72b2fe7 100644
--- a/searchsummary/src/vespa/searchsummary/docsummary/CMakeLists.txt
+++ b/searchsummary/src/vespa/searchsummary/docsummary/CMakeLists.txt
@@ -25,6 +25,7 @@ vespa_add_library(searchsummary_docsummary OBJECT
     positionsdfw.cpp
     linguisticsannotation.cpp
     searchdatatype.cpp
+    struct_map_attribute_combiner_dfw.cpp
     summaryfieldconverter.cpp
     AFTER
     searchsummary_config
diff --git a/searchsummary/src/vespa/searchsummary/docsummary/attribute_combiner_dfw.cpp b/searchsummary/src/vespa/searchsummary/docsummary/attribute_combiner_dfw.cpp
index b532cfb273a..e72caf9405b 100644
--- a/searchsummary/src/vespa/searchsummary/docsummary/attribute_combiner_dfw.cpp
+++ b/searchsummary/src/vespa/searchsummary/docsummary/attribute_combiner_dfw.cpp
@@ -2,6 +2,7 @@
 
 #include "attribute_combiner_dfw.h"
 #include "array_attribute_combiner_dfw.h"
+#include "struct_map_attribute_combiner_dfw.h"
 #include "docsum_field_writer_state.h"
 #include "docsumstate.h"
 #include <vespa/searchlib/attribute/attributeguard.h>
@@ -117,8 +118,7 @@ AttributeCombinerDFW::create(const vespalib::string &fieldName, IAttributeManage
     if (structFields.getError()) {
         return std::unique_ptr<IDocsumFieldWriter>();
     } else if (!structFields.getMapFields().empty()) {
-        LOG(warning, "map of struct is not yet supported for field '%s'", fieldName.c_str());
-        return std::unique_ptr<IDocsumFieldWriter>();
+        return std::make_unique<StructMapAttributeCombinerDFW>(fieldName, structFields.getMapFields());
     }
     return std::make_unique<ArrayAttributeCombinerDFW>(fieldName, structFields.getArrayFields());
 }
diff --git a/searchsummary/src/vespa/searchsummary/docsummary/struct_map_attribute_combiner_dfw.cpp b/searchsummary/src/vespa/searchsummary/docsummary/struct_map_attribute_combiner_dfw.cpp
new file mode 100644
index 00000000000..3395727b290
--- /dev/null
+++ b/searchsummary/src/vespa/searchsummary/docsummary/struct_map_attribute_combiner_dfw.cpp
@@ -0,0 +1,116 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "struct_map_attribute_combiner_dfw.h"
+#include "docsum_field_writer_state.h"
+#include "attribute_field_writer.h"
+#include <vespa/searchcommon/attribute/iattributecontext.h>
+#include <vespa/searchcommon/attribute/iattributevector.h>
+#include <vespa/vespalib/data/slime/cursor.h>
+
+using search::attribute::IAttributeContext;
+using search::attribute::IAttributeVector;
+using vespalib::slime::Cursor;
+
+namespace search::docsummary {
+
+namespace {
+
+vespalib::Memory keyName("key");
+vespalib::Memory valueName("value");
+
+class StructMapAttributeFieldWriterState : public DocsumFieldWriterState
+{
+    std::unique_ptr<AttributeFieldWriter> _keyWriter;
+    std::vector<std::unique_ptr<AttributeFieldWriter>> _writers;
+
+public:
+    StructMapAttributeFieldWriterState(const vespalib::string &keyAttributeName,
+                                       const std::vector<vespalib::string> &fieldNames,
+                                       const std::vector<vespalib::string> &attributeNames,
+                                       IAttributeContext &context);
+    ~StructMapAttributeFieldWriterState() override;
+    void insertField(uint32_t docId, vespalib::slime::Inserter &target) override;
+};
+
+StructMapAttributeFieldWriterState::StructMapAttributeFieldWriterState(const vespalib::string &keyAttributeName,
+                                                                       const std::vector<vespalib::string> &fieldNames,
+                                                                       const std::vector<vespalib::string> &attributeNames,
+                                                                       IAttributeContext &context)
+    : DocsumFieldWriterState(),
+      _keyWriter(),
+      _writers()
+{
+    const IAttributeVector *attr = context.getAttribute(keyAttributeName);
+    if (attr != nullptr) {
+        _keyWriter = AttributeFieldWriter::create(keyName, *attr);
+    }
+    size_t fields = fieldNames.size();
+    _writers.reserve(fields);
+    for (uint32_t field = 0; field < fields; ++field) {
+        attr = context.getAttribute(attributeNames[field]);
+        if (attr != nullptr) {
+            _writers.emplace_back(AttributeFieldWriter::create(fieldNames[field], *attr));
+        }
+    }
+}
+
+StructMapAttributeFieldWriterState::~StructMapAttributeFieldWriterState() = default;
+
+void
+StructMapAttributeFieldWriterState::insertField(uint32_t docId, vespalib::slime::Inserter &target)
+{
+    uint32_t elems = 0;
+    if (_keyWriter) {
+        _keyWriter->fetch(docId);
+        if (elems < _keyWriter->size()) {
+            elems = _keyWriter->size();
+        }
+    }
+    for (auto &writer : _writers) {
+        writer->fetch(docId);
+        if (elems < writer->size()) {
+            elems = writer->size();
+        }
+    }
+    if (elems == 0) {
+        return;
+    }
+    Cursor &arr = target.insertArray();
+    for (uint32_t idx = 0; idx < elems; ++idx) {
+        Cursor &keyValueObj = arr.addObject();
+        if (_keyWriter) {
+            _keyWriter->print(idx, keyValueObj);
+        }
+        Cursor &obj = keyValueObj.setObject(valueName);
+        for (auto &writer : _writers) {
+            writer->print(idx, obj);
+        }
+    }
+}
+
+}
+
+StructMapAttributeCombinerDFW::StructMapAttributeCombinerDFW(const vespalib::string &fieldName,
+                                                             const std::vector<vespalib::string> &fields)
+    : AttributeCombinerDFW(fieldName),
+      _keyAttributeName(),
+      _fields(fields),
+      _attributeNames()
+{
+    _keyAttributeName = fieldName + ".key";
+    _attributeNames.reserve(_fields.size());
+    vespalib::string prefix = fieldName + ".value.";
+    for (const auto &field : _fields) {
+        _attributeNames.emplace_back(prefix + field);
+    }
+}
+
+StructMapAttributeCombinerDFW::~StructMapAttributeCombinerDFW() = default;
+
+std::unique_ptr<DocsumFieldWriterState>
+StructMapAttributeCombinerDFW::allocFieldWriterState(IAttributeContext &context)
+{
+    return std::make_unique<StructMapAttributeFieldWriterState>(_keyAttributeName, _fields, _attributeNames, context);
+}
+
+}
diff --git a/searchsummary/src/vespa/searchsummary/docsummary/struct_map_attribute_combiner_dfw.h b/searchsummary/src/vespa/searchsummary/docsummary/struct_map_attribute_combiner_dfw.h
new file mode 100644
index 00000000000..553d82f6754
--- /dev/null
+++ b/searchsummary/src/vespa/searchsummary/docsummary/struct_map_attribute_combiner_dfw.h
@@ -0,0 +1,30 @@
+// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#pragma once
+
+#include "attribute_combiner_dfw.h"
+
+namespace search::attribute { class IAttributeContext; }
+
+namespace search::docsummary {
+
+class DocsumFieldWriterState;
+
+/*
+ * This class reads values from multiple struct field attributes and
+ * inserts them as a map of struct.
+ */
+class StructMapAttributeCombinerDFW : public AttributeCombinerDFW
+{
+    vespalib::string              _keyAttributeName;
+    std::vector<vespalib::string> _fields;
+    std::vector<vespalib::string> _attributeNames;
+
+    std::unique_ptr<DocsumFieldWriterState> allocFieldWriterState(search::attribute::IAttributeContext &context) override;
+public:
+    StructMapAttributeCombinerDFW(const vespalib::string &fieldName,
+                              const std::vector<vespalib::string> &fields);
+    ~StructMapAttributeCombinerDFW() override;
+};
+
+}