Add imported fields to document configs

This adds the field names of all imported fields in a search definition
to the document configs associated with it (document manager and document
types config for Java and C++, respectively). This enables consumers of
these configs to distinguish between field references to imported fields
and fields that don't exist in the document schema itself.

20 files changed, 555 insertions, 41 deletions

diff --git a/config-model/src/main/java/com/yahoo/documentmodel/NewDocumentType.java b/config-model/src/main/java/com/yahoo/documentmodel/NewDocumentType.java
index fc42864f1d0..41a30c4553d 100644
--- a/config-model/src/main/java/com/yahoo/documentmodel/NewDocumentType.java
+++ b/config-model/src/main/java/com/yahoo/documentmodel/NewDocumentType.java
@@ -69,25 +69,37 @@ public final class NewDocumentType extends StructuredDataType implements DataTyp
     private final StructDataType body;
     private final Set<FieldSet> fieldSets = new LinkedHashSet<>();
     private final Set<Name> documentReferences;
+    // Imported fields are virtual and therefore exist outside of the SD's document field definition
+    // block itself. But for features like imported fields in a non-search context (e.g. GC selections)
+    // it is necessary to know that certain identifiers refer to imported fields instead of being unknown
+    // document fields. To achieve this, we track the names of imported fields as part of the document
+    // config itself.
+    private final Set<String> importedFieldNames;
 
     public NewDocumentType(Name name) {
         this(name, emptySet());
     }
 
-    public NewDocumentType(Name name, Set<Name> documentReferences) {
+    public NewDocumentType(Name name, Set<Name> documentReferences, Set<String> importedFieldNames) {
         this(
                 name,
                 new StructDataType(name.getName() + ".header"),
                 new StructDataType(name.getName() + ".body"),
                 new FieldSets(),
-                documentReferences);
+                documentReferences,
+                importedFieldNames);
+    }
+
+    public NewDocumentType(Name name, Set<Name> documentReferences) {
+        this(name, documentReferences, emptySet());
     }
 
     public NewDocumentType(Name name,
                            StructDataType header,
                            StructDataType body,
                            FieldSets fs,
-                           Set<Name> documentReferences) {
+                           Set<Name> documentReferences,
+                           Set<String> importedFieldNames) {
         super(name.getName());
         this.name = name;
         this.header = header;
@@ -102,6 +114,7 @@ public final class NewDocumentType extends StructuredDataType implements DataTyp
             }
         }
         this.documentReferences = documentReferences;
+        this.importedFieldNames = importedFieldNames;
     }
 
     public Name getFullName() {
@@ -389,4 +402,8 @@ public final class NewDocumentType extends StructuredDataType implements DataTyp
         return documentReferences;
     }
 
+    public Set<String> getImportedFieldNames() {
+        return importedFieldNames;
+    }
+
 }
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/DocumentModelBuilder.java b/config-model/src/main/java/com/yahoo/searchdefinition/DocumentModelBuilder.java
index f0b1b427531..d3a78321106 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/DocumentModelBuilder.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/DocumentModelBuilder.java
@@ -18,6 +18,7 @@ import com.yahoo.documentmodel.VespaDocumentType;
 import com.yahoo.searchdefinition.document.Attribute;
 import com.yahoo.searchdefinition.document.SDDocumentType;
 import com.yahoo.searchdefinition.document.SDField;
+import com.yahoo.searchdefinition.document.TemporaryImportedFields;
 import com.yahoo.searchdefinition.document.annotation.SDAnnotationType;
 import com.yahoo.searchdefinition.document.annotation.TemporaryAnnotationReferenceDataType;
 import com.yahoo.vespa.documentmodel.DocumentModel;
@@ -27,6 +28,7 @@ import com.yahoo.vespa.documentmodel.SearchField;
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedList;
@@ -338,7 +340,8 @@ public class DocumentModelBuilder {
                                                  sdoc.getDocumentType().contentStruct(),
                                                  sdoc.getDocumentType().getBodyType(),
                                                  sdoc.getFieldSets(),
-                                                 convertDocumentReferencesToNames(sdoc.getDocumentReferences()));
+                                                 convertDocumentReferencesToNames(sdoc.getDocumentReferences()),
+                                                 convertTemporaryImportedFieldsToNames(sdoc.getTemporaryImportedFields()));
         for (SDDocumentType n : sdoc.getInheritedTypes()) {
             NewDocumentType.Name name = new NewDocumentType.Name(n.getName());
                 NewDocumentType inherited =  model.getDocumentManager().getDocumentType(name);
@@ -404,6 +407,13 @@ public class DocumentModelBuilder {
                 .collect(toSet());
     }
 
+    private static Set<String> convertTemporaryImportedFieldsToNames(TemporaryImportedFields importedFields) {
+        if (importedFields == null) {
+            return emptySet();
+        }
+        return Collections.unmodifiableSet(importedFields.fields().keySet());
+    }
+
     private static void extractDataTypesFromFields(NewDocumentType dt, Collection<Field> fields) {
         for (Field f : fields) {
             DataType type = f.getDataType();
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/ImportedFieldsEnumerator.java b/config-model/src/main/java/com/yahoo/searchdefinition/ImportedFieldsEnumerator.java
new file mode 100644
index 00000000000..c736ca8e9dc
--- /dev/null
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/ImportedFieldsEnumerator.java
@@ -0,0 +1,32 @@
+package com.yahoo.searchdefinition;
+
+import com.yahoo.searchdefinition.document.SDDocumentType;
+import com.yahoo.searchdefinition.document.TemporaryImportedFields;
+
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Enumerates and emplaces a set of all imported fields into a SDDocumentType from
+ * its corresponding Search instance.
+ */
+public class ImportedFieldsEnumerator {
+
+    private final List<Search> searchDefinitions;
+
+    public ImportedFieldsEnumerator(List<Search> searchDefinitions) {
+        this.searchDefinitions = searchDefinitions;
+    }
+
+    public void enumerateImportedFields(SDDocumentType documentType) {
+        var search = this.searchDefinitions.stream()
+                .filter(s -> s.getDocument() != null)
+                .filter(s -> s.getDocument().getName().equals(documentType.getName()))
+                .findFirst();
+        if (search.isEmpty()) {
+            return; // No imported fields present.
+        }
+        search.get().temporaryImportedFields().ifPresent(documentType::setTemporaryImportedFields);
+    }
+
+}
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/SearchBuilder.java b/config-model/src/main/java/com/yahoo/searchdefinition/SearchBuilder.java
index 949539ff99f..eb68e6af203 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/SearchBuilder.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/SearchBuilder.java
@@ -230,20 +230,22 @@ public class SearchBuilder {
                 sdocs.add(search.getDocument());
             }
         }
-        SDDocumentTypeOrderer orderer = new SDDocumentTypeOrderer(sdocs, deployLogger);
+        var orderer = new SDDocumentTypeOrderer(sdocs, deployLogger);
         orderer.process();
         for (SDDocumentType sdoc : orderer.getOrdered()) {
             new FieldOperationApplierForStructs().process(sdoc);
             new FieldOperationApplier().process(sdoc);
         }
 
-        DocumentReferenceResolver resolver = new DocumentReferenceResolver(searchList);
+        var resolver = new DocumentReferenceResolver(searchList);
         sdocs.forEach(resolver::resolveReferences);
+        var importedFieldsEnumerator = new ImportedFieldsEnumerator(searchList);
+        sdocs.forEach(importedFieldsEnumerator::enumerateImportedFields);
 
         if (validate)
             new DocumentGraphValidator().validateDocumentGraph(sdocs);
 
-        DocumentModelBuilder builder = new DocumentModelBuilder(model);
+        var builder = new DocumentModelBuilder(model);
         for (Search search : new SearchOrderer().order(searchList)) {
             new FieldOperationApplierForSearch().process(search); // TODO: Why is this not in the regular list?
             process(search, deployLogger, new QueryProfiles(queryProfileRegistry, deployLogger), validate);
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/document/SDDocumentType.java b/config-model/src/main/java/com/yahoo/searchdefinition/document/SDDocumentType.java
index 414a605c621..b3f98cc6f26 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/document/SDDocumentType.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/document/SDDocumentType.java
@@ -47,6 +47,7 @@ public class SDDocumentType implements Cloneable, Serializable {
     private FieldSets fieldSets;
     // Document references
     private Optional<DocumentReferences> documentReferences = Optional.empty();
+    private TemporaryImportedFields temporaryImportedFields;
 
     static {
         VESPA_DOCUMENT = new SDDocumentType(VespaDocumentType.INSTANCE.getFullName().getName());
@@ -58,6 +59,7 @@ public class SDDocumentType implements Cloneable, Serializable {
         type.docType = docType.clone();
         type.inheritedTypes.putAll(inheritedTypes);
         type.structType = structType;
+        // TODO this isn't complete; should it be..?!
         return type;
     }
 
@@ -334,4 +336,11 @@ public class SDDocumentType implements Cloneable, Serializable {
         this.documentReferences = Optional.of(documentReferences);
     }
 
+    public TemporaryImportedFields getTemporaryImportedFields() {
+        return temporaryImportedFields;
+    }
+
+    public void setTemporaryImportedFields(TemporaryImportedFields temporaryImportedFields) {
+        this.temporaryImportedFields = temporaryImportedFields;
+    }
 }
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/processing/ImportedFieldsResolver.java b/config-model/src/main/java/com/yahoo/searchdefinition/processing/ImportedFieldsResolver.java
index d6c334ee80b..6d3de23238d 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/processing/ImportedFieldsResolver.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/processing/ImportedFieldsResolver.java
@@ -64,7 +64,7 @@ public class ImportedFieldsResolver extends Processor {
     }
 
     private void resolveImportedPositionField(TemporaryImportedField importedField, DocumentReference reference,
-                                                   ImmutableSDField targetField, boolean validate) {
+                                              ImmutableSDField targetField, boolean validate) {
         TemporaryImportedField importedZCurveField = new TemporaryImportedField(PositionDataType.getZCurveFieldName(importedField.fieldName()),
                 reference.referenceField().getName(), PositionDataType.getZCurveFieldName(targetField.getName()));
         ImmutableSDField targetZCurveField = getTargetField(importedZCurveField, reference);
@@ -175,7 +175,7 @@ public class ImportedFieldsResolver extends Processor {
     }
 
     private void validateTargetField(TemporaryImportedField importedField,
-                                                 ImmutableSDField targetField, DocumentReference reference) {
+                                     ImmutableSDField targetField, DocumentReference reference) {
         if (!targetField.doesAttributing()) {
             fail(importedField, targetFieldAsString(targetField.getName(), reference) +
                     ": Is not an attribute field. Only attribute fields supported");
diff --git a/config-model/src/main/java/com/yahoo/vespa/configmodel/producers/DocumentManager.java b/config-model/src/main/java/com/yahoo/vespa/configmodel/producers/DocumentManager.java
index 02d500931d7..e0d015cc8b2 100644
--- a/config-model/src/main/java/com/yahoo/vespa/configmodel/producers/DocumentManager.java
+++ b/config-model/src/main/java/com/yahoo/vespa/configmodel/producers/DocumentManager.java
@@ -62,6 +62,7 @@ public class DocumentManager {
             }
         }
     }
+
     private void buildConfig(Collection<AnnotationType> types, DocumentmanagerConfig.Builder builder) {
         for (AnnotationType type : types) {
             DocumentmanagerConfig.Annotationtype.Builder atb = new DocumentmanagerConfig.Annotationtype.Builder();
@@ -110,6 +111,7 @@ public class DocumentManager {
                 doc.inherits(new Datatype.Documenttype.Inherits.Builder().name(inherited.getName()));
             }
             buildConfig(dt.getFieldSets(), doc);
+            buildImportedFieldsConfig(dt.getImportedFieldNames(), doc);
         } else if (type instanceof TemporaryStructuredDataType) {
             //Ignored
         } else if (type instanceof StructDataType) {
@@ -164,4 +166,12 @@ public class DocumentManager {
         doc.fieldsets(fs.getName(), new Datatype.Documenttype.Fieldsets.Builder().fields(fs.getFieldNames()));
     }
 
+    private void buildImportedFieldsConfig(Collection<String> fieldNames, Datatype.Documenttype.Builder builder) {
+        for (String fieldName : fieldNames) {
+            var ib = new DocumentmanagerConfig.Datatype.Documenttype.Importedfield.Builder();
+            ib.name(fieldName);
+            builder.importedfield(ib);
+        }
+    }
+
 }
diff --git a/config-model/src/main/java/com/yahoo/vespa/configmodel/producers/DocumentTypes.java b/config-model/src/main/java/com/yahoo/vespa/configmodel/producers/DocumentTypes.java
index d4228b52746..e6bf826dccc 100644
--- a/config-model/src/main/java/com/yahoo/vespa/configmodel/producers/DocumentTypes.java
+++ b/config-model/src/main/java/com/yahoo/vespa/configmodel/producers/DocumentTypes.java
@@ -58,6 +58,7 @@ public class DocumentTypes {
             buildConfig(annotation, atb);
         }
         buildConfig(documentType.getFieldSets(), db);
+        buildImportedFieldsConfig(documentType.getImportedFieldNames(), db);
         builder.documenttype(db);
     }
 
@@ -120,6 +121,14 @@ public class DocumentTypes {
         }
     }
 
+    private void buildImportedFieldsConfig(Collection<String> fieldNames, DocumenttypesConfig.Documenttype.Builder  builder) {
+        for (String fieldName : fieldNames) {
+            var ib = new DocumenttypesConfig.Documenttype.Importedfield.Builder();
+            ib.name(fieldName);
+            builder.importedfield(ib);
+        }
+    }
+
     private void buildConfig(StructDataType type,
                              DocumenttypesConfig.Documenttype.Datatype.Builder dataTypeBuilder,
                              DocumenttypesConfig.Documenttype.Builder documentBuilder,
diff --git a/config-model/src/test/configmodel/types/references/documentmanager_multiple_imported_fields.cfg b/config-model/src/test/configmodel/types/references/documentmanager_multiple_imported_fields.cfg
new file mode 100644
index 00000000000..7b50176625d
--- /dev/null
+++ b/config-model/src/test/configmodel/types/references/documentmanager_multiple_imported_fields.cfg
@@ -0,0 +1,104 @@
+enablecompression false
+datatype[0].id 1381038251
+datatype[0].structtype[0].name "position"
+datatype[0].structtype[0].version 0
+datatype[0].structtype[0].compresstype NONE
+datatype[0].structtype[0].compresslevel 0
+datatype[0].structtype[0].compressthreshold 95
+datatype[0].structtype[0].compressminsize 800
+datatype[0].structtype[0].field[0].name "x"
+datatype[0].structtype[0].field[0].datatype 0
+datatype[0].structtype[0].field[0].detailedtype ""
+datatype[0].structtype[0].field[1].name "y"
+datatype[0].structtype[0].field[1].datatype 0
+datatype[0].structtype[0].field[1].detailedtype ""
+datatype[1].id 595216861
+datatype[1].referencetype[0].target_type_id -1318255918
+datatype[2].id 542332920
+datatype[2].referencetype[0].target_type_id 443162583
+datatype[3].id 959075962
+datatype[3].structtype[0].name "ad.header"
+datatype[3].structtype[0].version 0
+datatype[3].structtype[0].compresstype NONE
+datatype[3].structtype[0].compresslevel 0
+datatype[3].structtype[0].compressthreshold 95
+datatype[3].structtype[0].compressminsize 800
+datatype[3].structtype[0].field[0].name "campaign_ref"
+datatype[3].structtype[0].field[0].datatype 595216861
+datatype[3].structtype[0].field[0].detailedtype ""
+datatype[3].structtype[0].field[1].name "person_ref"
+datatype[3].structtype[0].field[1].datatype 542332920
+datatype[3].structtype[0].field[1].detailedtype ""
+datatype[4].id -255288561
+datatype[4].structtype[0].name "ad.body"
+datatype[4].structtype[0].version 0
+datatype[4].structtype[0].compresstype NONE
+datatype[4].structtype[0].compresslevel 0
+datatype[4].structtype[0].compressthreshold 95
+datatype[4].structtype[0].compressminsize 800
+datatype[5].id 2987301
+datatype[5].documenttype[0].name "ad"
+datatype[5].documenttype[0].version 0
+datatype[5].documenttype[0].inherits[0].name "document"
+datatype[5].documenttype[0].inherits[0].version 0
+datatype[5].documenttype[0].headerstruct 959075962
+datatype[5].documenttype[0].bodystruct -255288561
+datatype[5].documenttype[0].fieldsets{[document]}.fields[0] "campaign_ref"
+datatype[5].documenttype[0].fieldsets{[document]}.fields[1] "person_ref"
+datatype[5].documenttype[0].importedfield[0].name "my_cool_field"
+datatype[5].documenttype[0].importedfield[1].name "my_swag_field"
+datatype[5].documenttype[0].importedfield[2].name "my_name"
+datatype[6].id -2041471955
+datatype[6].structtype[0].name "campaign.header"
+datatype[6].structtype[0].version 0
+datatype[6].structtype[0].compresstype NONE
+datatype[6].structtype[0].compresslevel 0
+datatype[6].structtype[0].compressthreshold 95
+datatype[6].structtype[0].compressminsize 800
+datatype[6].structtype[0].field[0].name "cool_field"
+datatype[6].structtype[0].field[0].datatype 2
+datatype[6].structtype[0].field[0].detailedtype ""
+datatype[6].structtype[0].field[1].name "swag_field"
+datatype[6].structtype[0].field[1].datatype 4
+datatype[6].structtype[0].field[1].detailedtype ""
+datatype[7].id 1448849794
+datatype[7].structtype[0].name "campaign.body"
+datatype[7].structtype[0].version 0
+datatype[7].structtype[0].compresstype NONE
+datatype[7].structtype[0].compresslevel 0
+datatype[7].structtype[0].compressthreshold 95
+datatype[7].structtype[0].compressminsize 800
+datatype[8].id -1318255918
+datatype[8].documenttype[0].name "campaign"
+datatype[8].documenttype[0].version 0
+datatype[8].documenttype[0].inherits[0].name "document"
+datatype[8].documenttype[0].inherits[0].version 0
+datatype[8].documenttype[0].headerstruct -2041471955
+datatype[8].documenttype[0].bodystruct 1448849794
+datatype[8].documenttype[0].fieldsets{[document]}.fields[0] "cool_field"
+datatype[8].documenttype[0].fieldsets{[document]}.fields[1] "swag_field"
+datatype[9].id 3129224
+datatype[9].structtype[0].name "person.header"
+datatype[9].structtype[0].version 0
+datatype[9].structtype[0].compresstype NONE
+datatype[9].structtype[0].compresslevel 0
+datatype[9].structtype[0].compressthreshold 95
+datatype[9].structtype[0].compressminsize 800
+datatype[9].structtype[0].field[0].name "name"
+datatype[9].structtype[0].field[0].datatype 2
+datatype[9].structtype[0].field[0].detailedtype ""
+datatype[10].id -2003767395
+datatype[10].structtype[0].name "person.body"
+datatype[10].structtype[0].version 0
+datatype[10].structtype[0].compresstype NONE
+datatype[10].structtype[0].compresslevel 0
+datatype[10].structtype[0].compressthreshold 95
+datatype[10].structtype[0].compressminsize 800
+datatype[11].id 443162583
+datatype[11].documenttype[0].name "person"
+datatype[11].documenttype[0].version 0
+datatype[11].documenttype[0].inherits[0].name "document"
+datatype[11].documenttype[0].inherits[0].version 0
+datatype[11].documenttype[0].headerstruct 3129224
+datatype[11].documenttype[0].bodystruct -2003767395
+datatype[11].documenttype[0].fieldsets{[document]}.fields[0] "name"
\ No newline at end of file
diff --git a/config-model/src/test/configmodel/types/references/documenttypes_multiple_imported_fields.cfg b/config-model/src/test/configmodel/types/references/documenttypes_multiple_imported_fields.cfg
new file mode 100644
index 00000000000..7859703ffe0
--- /dev/null
+++ b/config-model/src/test/configmodel/types/references/documenttypes_multiple_imported_fields.cfg
@@ -0,0 +1,141 @@
+enablecompression false
+documenttype[0].id 2987301
+documenttype[0].name "ad"
+documenttype[0].version 0
+documenttype[0].headerstruct 959075962
+documenttype[0].bodystruct -255288561
+documenttype[0].inherits[0].id 8
+documenttype[0].datatype[0].id 959075962
+documenttype[0].datatype[0].type STRUCT
+documenttype[0].datatype[0].array.element.id 0
+documenttype[0].datatype[0].map.key.id 0
+documenttype[0].datatype[0].map.value.id 0
+documenttype[0].datatype[0].wset.key.id 0
+documenttype[0].datatype[0].wset.createifnonexistent false
+documenttype[0].datatype[0].wset.removeifzero false
+documenttype[0].datatype[0].annotationref.annotation.id 0
+documenttype[0].datatype[0].sstruct.name "ad.header"
+documenttype[0].datatype[0].sstruct.version 0
+documenttype[0].datatype[0].sstruct.compression.type NONE
+documenttype[0].datatype[0].sstruct.compression.level 0
+documenttype[0].datatype[0].sstruct.compression.threshold 95
+documenttype[0].datatype[0].sstruct.compression.minsize 200
+documenttype[0].datatype[0].sstruct.field[0].name "campaign_ref"
+documenttype[0].datatype[0].sstruct.field[0].id 23963250
+documenttype[0].datatype[0].sstruct.field[0].datatype 595216861
+documenttype[0].datatype[0].sstruct.field[0].detailedtype ""
+documenttype[0].datatype[0].sstruct.field[1].name "person_ref"
+documenttype[0].datatype[0].sstruct.field[1].id 100779805
+documenttype[0].datatype[0].sstruct.field[1].datatype 542332920
+documenttype[0].datatype[0].sstruct.field[1].detailedtype ""
+documenttype[0].datatype[1].id -255288561
+documenttype[0].datatype[1].type STRUCT
+documenttype[0].datatype[1].array.element.id 0
+documenttype[0].datatype[1].map.key.id 0
+documenttype[0].datatype[1].map.value.id 0
+documenttype[0].datatype[1].wset.key.id 0
+documenttype[0].datatype[1].wset.createifnonexistent false
+documenttype[0].datatype[1].wset.removeifzero false
+documenttype[0].datatype[1].annotationref.annotation.id 0
+documenttype[0].datatype[1].sstruct.name "ad.body"
+documenttype[0].datatype[1].sstruct.version 0
+documenttype[0].datatype[1].sstruct.compression.type NONE
+documenttype[0].datatype[1].sstruct.compression.level 0
+documenttype[0].datatype[1].sstruct.compression.threshold 95
+documenttype[0].datatype[1].sstruct.compression.minsize 200
+documenttype[0].fieldsets{[document]}.fields[0] "campaign_ref"
+documenttype[0].fieldsets{[document]}.fields[1] "person_ref"
+documenttype[0].referencetype[0].id 595216861
+documenttype[0].referencetype[0].target_type_id -1318255918
+documenttype[0].referencetype[1].id 542332920
+documenttype[0].referencetype[1].target_type_id 443162583
+documenttype[0].importedfield[0].name "my_cool_field"
+documenttype[0].importedfield[1].name "my_swag_field"
+documenttype[0].importedfield[2].name "my_name"
+documenttype[1].id -1318255918
+documenttype[1].name "campaign"
+documenttype[1].version 0
+documenttype[1].headerstruct -2041471955
+documenttype[1].bodystruct 1448849794
+documenttype[1].inherits[0].id 8
+documenttype[1].datatype[0].id -2041471955
+documenttype[1].datatype[0].type STRUCT
+documenttype[1].datatype[0].array.element.id 0
+documenttype[1].datatype[0].map.key.id 0
+documenttype[1].datatype[0].map.value.id 0
+documenttype[1].datatype[0].wset.key.id 0
+documenttype[1].datatype[0].wset.createifnonexistent false
+documenttype[1].datatype[0].wset.removeifzero false
+documenttype[1].datatype[0].annotationref.annotation.id 0
+documenttype[1].datatype[0].sstruct.name "campaign.header"
+documenttype[1].datatype[0].sstruct.version 0
+documenttype[1].datatype[0].sstruct.compression.type NONE
+documenttype[1].datatype[0].sstruct.compression.level 0
+documenttype[1].datatype[0].sstruct.compression.threshold 95
+documenttype[1].datatype[0].sstruct.compression.minsize 200
+documenttype[1].datatype[0].sstruct.field[0].name "cool_field"
+documenttype[1].datatype[0].sstruct.field[0].id 1588702436
+documenttype[1].datatype[0].sstruct.field[0].datatype 2
+documenttype[1].datatype[0].sstruct.field[0].detailedtype ""
+documenttype[1].datatype[0].sstruct.field[1].name "swag_field"
+documenttype[1].datatype[0].sstruct.field[1].id 1691224741
+documenttype[1].datatype[0].sstruct.field[1].datatype 4
+documenttype[1].datatype[0].sstruct.field[1].detailedtype ""
+documenttype[1].datatype[1].id 1448849794
+documenttype[1].datatype[1].type STRUCT
+documenttype[1].datatype[1].array.element.id 0
+documenttype[1].datatype[1].map.key.id 0
+documenttype[1].datatype[1].map.value.id 0
+documenttype[1].datatype[1].wset.key.id 0
+documenttype[1].datatype[1].wset.createifnonexistent false
+documenttype[1].datatype[1].wset.removeifzero false
+documenttype[1].datatype[1].annotationref.annotation.id 0
+documenttype[1].datatype[1].sstruct.name "campaign.body"
+documenttype[1].datatype[1].sstruct.version 0
+documenttype[1].datatype[1].sstruct.compression.type NONE
+documenttype[1].datatype[1].sstruct.compression.level 0
+documenttype[1].datatype[1].sstruct.compression.threshold 95
+documenttype[1].datatype[1].sstruct.compression.minsize 200
+documenttype[1].fieldsets{[document]}.fields[0] "cool_field"
+documenttype[1].fieldsets{[document]}.fields[1] "swag_field"
+documenttype[2].id 443162583
+documenttype[2].name "person"
+documenttype[2].version 0
+documenttype[2].headerstruct 3129224
+documenttype[2].bodystruct -2003767395
+documenttype[2].inherits[0].id 8
+documenttype[2].datatype[0].id 3129224
+documenttype[2].datatype[0].type STRUCT
+documenttype[2].datatype[0].array.element.id 0
+documenttype[2].datatype[0].map.key.id 0
+documenttype[2].datatype[0].map.value.id 0
+documenttype[2].datatype[0].wset.key.id 0
+documenttype[2].datatype[0].wset.createifnonexistent false
+documenttype[2].datatype[0].wset.removeifzero false
+documenttype[2].datatype[0].annotationref.annotation.id 0
+documenttype[2].datatype[0].sstruct.name "person.header"
+documenttype[2].datatype[0].sstruct.version 0
+documenttype[2].datatype[0].sstruct.compression.type NONE
+documenttype[2].datatype[0].sstruct.compression.level 0
+documenttype[2].datatype[0].sstruct.compression.threshold 95
+documenttype[2].datatype[0].sstruct.compression.minsize 200
+documenttype[2].datatype[0].sstruct.field[0].name "name"
+documenttype[2].datatype[0].sstruct.field[0].id 1160796772
+documenttype[2].datatype[0].sstruct.field[0].datatype 2
+documenttype[2].datatype[0].sstruct.field[0].detailedtype ""
+documenttype[2].datatype[1].id -2003767395
+documenttype[2].datatype[1].type STRUCT
+documenttype[2].datatype[1].array.element.id 0
+documenttype[2].datatype[1].map.key.id 0
+documenttype[2].datatype[1].map.value.id 0
+documenttype[2].datatype[1].wset.key.id 0
+documenttype[2].datatype[1].wset.createifnonexistent false
+documenttype[2].datatype[1].wset.removeifzero false
+documenttype[2].datatype[1].annotationref.annotation.id 0
+documenttype[2].datatype[1].sstruct.name "person.body"
+documenttype[2].datatype[1].sstruct.version 0
+documenttype[2].datatype[1].sstruct.compression.type NONE
+documenttype[2].datatype[1].sstruct.compression.level 0
+documenttype[2].datatype[1].sstruct.compression.threshold 95
+documenttype[2].datatype[1].sstruct.compression.minsize 200
+documenttype[2].fieldsets{[document]}.fields[0] "name"
\ No newline at end of file
diff --git a/config-model/src/test/java/com/yahoo/searchdefinition/AttributeUtils.java b/config-model/src/test/java/com/yahoo/searchdefinition/AttributeUtils.java
new file mode 100644
index 00000000000..6ce5a430e92
--- /dev/null
+++ b/config-model/src/test/java/com/yahoo/searchdefinition/AttributeUtils.java
@@ -0,0 +1,14 @@
+package com.yahoo.searchdefinition;
+
+import com.yahoo.searchdefinition.document.SDField;
+
+/**
+ * Convenience class for tests that need to set attribute properties on fields.
+ */
+public class AttributeUtils {
+
+    public static void addAttributeAspect(SDField field) {
+        field.parseIndexingScript("{ attribute }");
+    }
+
+}
diff --git a/config-model/src/test/java/com/yahoo/searchdefinition/DocumentReferenceResolverTest.java b/config-model/src/test/java/com/yahoo/searchdefinition/DocumentReferenceResolverTest.java
index 8378ec811a5..e46208c770d 100644
--- a/config-model/src/test/java/com/yahoo/searchdefinition/DocumentReferenceResolverTest.java
+++ b/config-model/src/test/java/com/yahoo/searchdefinition/DocumentReferenceResolverTest.java
@@ -36,7 +36,7 @@ public class DocumentReferenceResolverTest {
         // Create foo document with document reference to bar and add another field
         SDField fooRefToBarField = new SDField
                 ("bar_ref", ReferenceDataType.createWithInferredId(barDocument.getDocumentType()));
-        addAttributeAspect(fooRefToBarField);
+        AttributeUtils.addAttributeAspect(fooRefToBarField);
         SDField irrelevantField = new SDField("irrelevant_stuff", DataType.INT);
         Search fooSearch = new Search();
         SDDocumentType fooDocument = new SDDocumentType("foo", fooSearch);
@@ -59,7 +59,7 @@ public class DocumentReferenceResolverTest {
         // Create foo document with document reference to non-existing document bar
         SDField fooRefToBarField = new SDField(
                 "bar_ref", ReferenceDataType.createWithInferredId(TemporaryStructuredDataType.create("bar")));
-        addAttributeAspect(fooRefToBarField);
+        AttributeUtils.addAttributeAspect(fooRefToBarField);
         Search fooSearch = new Search();
         SDDocumentType fooDocument = new SDDocumentType("foo", fooSearch);
         fooDocument.addField(fooRefToBarField);
@@ -95,8 +95,4 @@ public class DocumentReferenceResolverTest {
         resolver.resolveReferences(fooDocument);
     }
 
-    private static void addAttributeAspect(SDField fooRefToBarField) {
-        fooRefToBarField.parseIndexingScript("{ attribute }");
-    }
-
 }
diff --git a/config-model/src/test/java/com/yahoo/searchdefinition/ImportedFieldsEnumeratorTest.java b/config-model/src/test/java/com/yahoo/searchdefinition/ImportedFieldsEnumeratorTest.java
new file mode 100644
index 00000000000..d63f3dd903b
--- /dev/null
+++ b/config-model/src/test/java/com/yahoo/searchdefinition/ImportedFieldsEnumeratorTest.java
@@ -0,0 +1,65 @@
+package com.yahoo.searchdefinition;
+
+import com.yahoo.document.DataType;
+import com.yahoo.document.ReferenceDataType;
+import com.yahoo.searchdefinition.document.SDDocumentType;
+import com.yahoo.searchdefinition.document.SDField;
+import com.yahoo.searchdefinition.document.TemporaryImportedField;
+import org.junit.Test;
+
+import java.util.HashSet;
+import java.util.List;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+public class ImportedFieldsEnumeratorTest {
+
+    @Test
+    public void imported_fields_are_enumerated_and_copied_from_correct_search_instance() {
+        Search parentSearch = new Search();
+        SDDocumentType parentDocument = new SDDocumentType("parent", parentSearch);
+        var parentField = new SDField("their_field", DataType.INT);
+        AttributeUtils.addAttributeAspect(parentField);
+        parentDocument.addField(parentField);
+        parentSearch.addDocument(parentDocument);
+
+        Search fooSearch = new Search();
+        SDField fooRefToParent = new SDField(
+                "foo_ref", ReferenceDataType.createWithInferredId(parentDocument.getDocumentType()));
+        AttributeUtils.addAttributeAspect(fooRefToParent);
+        var fooImports = fooSearch.temporaryImportedFields().get();
+        fooImports.add(new TemporaryImportedField("my_first_import", "foo_ref", "their_field"));
+        fooImports.add(new TemporaryImportedField("my_second_import", "foo_ref", "their_field"));
+        SDDocumentType fooDocument = new SDDocumentType("foo", fooSearch);
+        fooSearch.addDocument(fooDocument);
+
+        Search barSearch = new Search();
+        SDField barRefToParent = new SDField(
+                "bar_ref", ReferenceDataType.createWithInferredId(parentDocument.getDocumentType()));
+        AttributeUtils.addAttributeAspect(barRefToParent);
+        var barImports = barSearch.temporaryImportedFields().get();
+        barImports.add(new TemporaryImportedField("my_cool_import", "my_ref", "their_field"));
+        SDDocumentType barDocument = new SDDocumentType("bar", barSearch);
+        barSearch.addDocument(barDocument);
+
+        var enumerator = new ImportedFieldsEnumerator(List.of(parentSearch, fooSearch, barSearch));
+
+        enumerator.enumerateImportedFields(parentDocument);
+        assertImportedFieldsAre(parentDocument, List.of()); // No imported fields in parent
+
+        enumerator.enumerateImportedFields(fooDocument);
+        assertImportedFieldsAre(fooDocument, List.of("my_first_import", "my_second_import"));
+
+        enumerator.enumerateImportedFields(barDocument);
+        assertImportedFieldsAre(barDocument, List.of("my_cool_import"));
+    }
+
+    private void assertImportedFieldsAre(SDDocumentType documentType, List<String> expectedNames) {
+        assertNotNull(documentType.getTemporaryImportedFields());
+        var actualNames = documentType.getTemporaryImportedFields().fields().keySet();
+        var expectedNameSet = new HashSet<>(expectedNames);
+        assertEquals(expectedNameSet, actualNames);
+    }
+
+}
diff --git a/config-model/src/test/java/com/yahoo/vespa/documentmodel/AbstractReferenceFieldTestCase.java b/config-model/src/test/java/com/yahoo/vespa/documentmodel/AbstractReferenceFieldTestCase.java
new file mode 100644
index 00000000000..b6498b48928
--- /dev/null
+++ b/config-model/src/test/java/com/yahoo/vespa/documentmodel/AbstractReferenceFieldTestCase.java
@@ -0,0 +1,34 @@
+package com.yahoo.vespa.documentmodel;
+
+import com.yahoo.document.DocumenttypesConfig;
+import com.yahoo.document.config.DocumentmanagerConfig;
+import com.yahoo.searchdefinition.SearchDefinitionTestCase;
+import com.yahoo.vespa.configmodel.producers.DocumentManager;
+import com.yahoo.vespa.configmodel.producers.DocumentTypes;
+
+import java.io.IOException;
+
+/**
+ * Utility functions for testing generated configs for reference/imported fields.
+ */
+public abstract class AbstractReferenceFieldTestCase extends SearchDefinitionTestCase {
+
+    private static String TEST_FOLDER = "src/test/configmodel/types/references/";
+
+    protected void assertDocumentConfigs(DocumentModel model,
+                                         String cfgFileSpec) throws IOException {
+        assertDocumentmanagerCfg(model, "documentmanager_" + cfgFileSpec + ".cfg");
+        assertDocumenttypesCfg(model , "documenttypes_" + cfgFileSpec + ".cfg");
+    }
+
+    protected void assertDocumentmanagerCfg(DocumentModel model, String documentmanagerCfgFile) throws IOException {
+        DocumentmanagerConfig.Builder documentmanagerCfg = new DocumentManager().produce(model, new DocumentmanagerConfig.Builder());
+        assertConfigFile(TEST_FOLDER + documentmanagerCfgFile, new DocumentmanagerConfig(documentmanagerCfg).toString());
+    }
+
+    protected void assertDocumenttypesCfg(DocumentModel model, String documenttypesCfgFile) throws IOException {
+        DocumenttypesConfig.Builder documenttypesCfg = new DocumentTypes().produce(model, new DocumenttypesConfig.Builder());
+        assertConfigFile(TEST_FOLDER + documenttypesCfgFile, new DocumenttypesConfig(documenttypesCfg).toString());
+    }
+
+}
diff --git a/config-model/src/test/java/com/yahoo/vespa/documentmodel/DocumentModelBuilderImportedFieldsTestCase.java b/config-model/src/test/java/com/yahoo/vespa/documentmodel/DocumentModelBuilderImportedFieldsTestCase.java
new file mode 100644
index 00000000000..3faf4118b8c
--- /dev/null
+++ b/config-model/src/test/java/com/yahoo/vespa/documentmodel/DocumentModelBuilderImportedFieldsTestCase.java
@@ -0,0 +1,54 @@
+package com.yahoo.vespa.documentmodel;
+
+import com.yahoo.searchdefinition.SearchBuilder;
+import com.yahoo.searchdefinition.parser.ParseException;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import static com.yahoo.config.model.test.TestUtil.joinLines;
+
+public class DocumentModelBuilderImportedFieldsTestCase extends AbstractReferenceFieldTestCase {
+
+    @Test
+    public void imported_fields_are_included_in_generated_document_configs() throws ParseException, IOException {
+        assertDocumentConfigs(new TestDocumentModelBuilder().addCampaign().addPerson().build(joinLines(
+                "search ad {",
+                "  document ad {",
+                "    field campaign_ref type reference<campaign> { indexing: attribute }",
+                "    field person_ref type reference<person> { indexing: attribute }",
+                "  }",
+                "  import field campaign_ref.cool_field as my_cool_field {}",
+                "  import field campaign_ref.swag_field as my_swag_field {}",
+                "  import field person_ref.name as my_name {}",
+                "}")),
+                "multiple_imported_fields");
+    }
+
+    private static class TestDocumentModelBuilder {
+        private final SearchBuilder builder = new SearchBuilder();
+        public TestDocumentModelBuilder addCampaign() throws ParseException {
+            builder.importString(joinLines("search campaign {",
+                    "  document campaign {",
+                    "    field cool_field type string { indexing: attribute }",
+                    "    field swag_field type long { indexing: attribute }",
+                    "  }",
+                    "}"));
+            return this;
+        }
+        public TestDocumentModelBuilder addPerson() throws ParseException {
+            builder.importString(joinLines("search person {",
+                    "  document person {",
+                    "    field name type string { indexing: attribute }",
+                    "  }",
+                    "}"));
+            return this;
+        }
+        public DocumentModel build(String adSdContent) throws ParseException {
+            builder.importString(adSdContent);
+            builder.build();
+            return builder.getModel();
+        }
+    }
+
+}
diff --git a/config-model/src/test/java/com/yahoo/vespa/documentmodel/DocumentModelBuilderReferenceTypeTestCase.java b/config-model/src/test/java/com/yahoo/vespa/documentmodel/DocumentModelBuilderReferenceTypeTestCase.java
index e9a7a6ed33e..55980ee5fea 100644
--- a/config-model/src/test/java/com/yahoo/vespa/documentmodel/DocumentModelBuilderReferenceTypeTestCase.java
+++ b/config-model/src/test/java/com/yahoo/vespa/documentmodel/DocumentModelBuilderReferenceTypeTestCase.java
@@ -1,15 +1,10 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.vespa.documentmodel;
 
-import com.yahoo.document.DocumenttypesConfig;
 import com.yahoo.document.ReferenceDataType;
-import com.yahoo.document.config.DocumentmanagerConfig;
 import com.yahoo.documentmodel.NewDocumentType;
 import com.yahoo.searchdefinition.SearchBuilder;
-import com.yahoo.searchdefinition.SearchDefinitionTestCase;
 import com.yahoo.searchdefinition.parser.ParseException;
-import com.yahoo.vespa.configmodel.producers.DocumentManager;
-import com.yahoo.vespa.configmodel.producers.DocumentTypes;
 import org.junit.Test;
 
 import java.io.IOException;
@@ -20,7 +15,7 @@ import static org.junit.Assert.assertEquals;
 /**
  * @author geirst
  */
-public class DocumentModelBuilderReferenceTypeTestCase extends SearchDefinitionTestCase {
+public class DocumentModelBuilderReferenceTypeTestCase extends AbstractReferenceFieldTestCase {
 
     @Test
     public void reference_fields_can_reference_other_document_types() throws ParseException, IOException {
@@ -60,24 +55,6 @@ public class DocumentModelBuilderReferenceTypeTestCase extends SearchDefinitionT
         assertEquals(campaignRefType.getTargetType(), campaignType);
     }
 
-    private static String TEST_FOLDER = "src/test/configmodel/types/references/";
-
-    private void assertDocumentConfigs(DocumentModel model,
-                                       String cfgFileSpec) throws IOException {
-        assertDocumentmanagerCfg(model, "documentmanager_" + cfgFileSpec + ".cfg");
-        assertDocumenttypesCfg(model , "documenttypes_" + cfgFileSpec + ".cfg");
-    }
-
-    private void assertDocumentmanagerCfg(DocumentModel model, String documentmanagerCfgFile) throws IOException {
-        DocumentmanagerConfig.Builder documentmanagerCfg = new DocumentManager().produce(model, new DocumentmanagerConfig.Builder());
-        assertConfigFile(TEST_FOLDER + documentmanagerCfgFile, new DocumentmanagerConfig(documentmanagerCfg).toString());
-    }
-
-    private void assertDocumenttypesCfg(DocumentModel model, String documenttypesCfgFile) throws IOException {
-        DocumenttypesConfig.Builder documenttypesCfg = new DocumentTypes().produce(model, new DocumenttypesConfig.Builder());
-        assertConfigFile(TEST_FOLDER + documenttypesCfgFile, new DocumenttypesConfig(documenttypesCfg).toString());
-    }
-
     private static class TestDocumentModelBuilder {
         private final SearchBuilder builder = new SearchBuilder();
         public TestDocumentModelBuilder addCampaign() throws ParseException {
diff --git a/config-model/src/test/java/com/yahoo/vespa/model/application/validation/change/search/DocumentTypeChangeValidatorTest.java b/config-model/src/test/java/com/yahoo/vespa/model/application/validation/change/search/DocumentTypeChangeValidatorTest.java
index 4064e53dfb7..3dfcef70aba 100644
--- a/config-model/src/test/java/com/yahoo/vespa/model/application/validation/change/search/DocumentTypeChangeValidatorTest.java
+++ b/config-model/src/test/java/com/yahoo/vespa/model/application/validation/change/search/DocumentTypeChangeValidatorTest.java
@@ -203,6 +203,7 @@ public class DocumentTypeChangeValidatorTest {
                 headerfields,
                 new StructDataType("bodyfields"),
                 new FieldSets(),
+                Collections.emptySet(),
                 Collections.emptySet());
     }
 
diff --git a/document/abi-spec.json b/document/abi-spec.json
index e4917a174a6..717b0c9f188 100644
--- a/document/abi-spec.json
+++ b/document/abi-spec.json
@@ -712,6 +712,8 @@
       "public com.yahoo.document.DocumenttypesConfig$Documenttype$Builder fieldsets(java.util.Map)",
       "public com.yahoo.document.DocumenttypesConfig$Documenttype$Builder referencetype(com.yahoo.document.DocumenttypesConfig$Documenttype$Referencetype$Builder)",
       "public com.yahoo.document.DocumenttypesConfig$Documenttype$Builder referencetype(java.util.List)",
+      "public com.yahoo.document.DocumenttypesConfig$Documenttype$Builder importedfield(com.yahoo.document.DocumenttypesConfig$Documenttype$Importedfield$Builder)",
+      "public com.yahoo.document.DocumenttypesConfig$Documenttype$Builder importedfield(java.util.List)",
       "public com.yahoo.document.DocumenttypesConfig$Documenttype build()"
     ],
     "fields": [
@@ -719,7 +721,8 @@
       "public java.util.List datatype",
       "public java.util.List annotationtype",
       "public java.util.Map fieldsets",
-      "public java.util.List referencetype"
+      "public java.util.List referencetype",
+      "public java.util.List importedfield"
     ]
   },
   "com.yahoo.document.DocumenttypesConfig$Documenttype$Datatype$Annotationref$Annotation$Builder": {
@@ -1264,6 +1267,35 @@
     ],
     "fields": []
   },
+  "com.yahoo.document.DocumenttypesConfig$Documenttype$Importedfield$Builder": {
+    "superClass": "java.lang.Object",
+    "interfaces": [
+      "com.yahoo.config.ConfigBuilder"
+    ],
+    "attributes": [
+      "public"
+    ],
+    "methods": [
+      "public void <init>()",
+      "public void <init>(com.yahoo.document.DocumenttypesConfig$Documenttype$Importedfield)",
+      "public com.yahoo.document.DocumenttypesConfig$Documenttype$Importedfield$Builder name(java.lang.String)",
+      "public com.yahoo.document.DocumenttypesConfig$Documenttype$Importedfield build()"
+    ],
+    "fields": []
+  },
+  "com.yahoo.document.DocumenttypesConfig$Documenttype$Importedfield": {
+    "superClass": "com.yahoo.config.InnerNode",
+    "interfaces": [],
+    "attributes": [
+      "public",
+      "final"
+    ],
+    "methods": [
+      "public void <init>(com.yahoo.document.DocumenttypesConfig$Documenttype$Importedfield$Builder)",
+      "public java.lang.String name()"
+    ],
+    "fields": []
+  },
   "com.yahoo.document.DocumenttypesConfig$Documenttype$Inherits$Builder": {
     "superClass": "java.lang.Object",
     "interfaces": [
@@ -1347,7 +1379,9 @@
       "public java.util.Map fieldsets()",
       "public com.yahoo.document.DocumenttypesConfig$Documenttype$Fieldsets fieldsets(java.lang.String)",
       "public java.util.List referencetype()",
-      "public com.yahoo.document.DocumenttypesConfig$Documenttype$Referencetype referencetype(int)"
+      "public com.yahoo.document.DocumenttypesConfig$Documenttype$Referencetype referencetype(int)",
+      "public java.util.List importedfield()",
+      "public com.yahoo.document.DocumenttypesConfig$Documenttype$Importedfield importedfield(int)"
     ],
     "fields": []
   },
diff --git a/document/src/vespa/document/config/documentmanager.def b/document/src/vespa/document/config/documentmanager.def
index 1961f67d83c..092a29d9293 100644
--- a/document/src/vespa/document/config/documentmanager.def
+++ b/document/src/vespa/document/config/documentmanager.def
@@ -93,6 +93,9 @@ datatype[].documenttype[].bodystruct int
 ## Field sets
 datatype[].documenttype[].fieldsets{}.fields[] string
 
+## Imported fields (specified outside the document block in the schema)
+datatype[].documenttype[].importedfield[].name string
+
 ## Cross-document reference with ID of target document type
 datatype[].referencetype[].target_type_id int
 
diff --git a/document/src/vespa/document/config/documenttypes.def b/document/src/vespa/document/config/documenttypes.def
index fb3fcd8b123..a9ebde90bb6 100644
--- a/document/src/vespa/document/config/documenttypes.def
+++ b/document/src/vespa/document/config/documenttypes.def
@@ -104,3 +104,5 @@ documenttype[].referencetype[].id int
 
 ## Numeric ID of the document type instances of the reference point to.
 documenttype[].referencetype[].target_type_id int
+
+documenttype[].importedfield[].name string