1 files changed, 71 insertions, 0 deletions
diff --git a/config-model/src/main/java/com/yahoo/schema/processing/IndexingValues.java b/config-model/src/main/java/com/yahoo/schema/processing/IndexingValues.java
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+++ b/config-model/src/main/java/com/yahoo/schema/processing/IndexingValues.java
@@ -0,0 +1,71 @@
+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.schema.processing;
+
+import com.yahoo.config.application.api.DeployLogger;
+import com.yahoo.schema.RankProfileRegistry;
+import com.yahoo.document.Field;
+import com.yahoo.schema.Schema;
+import com.yahoo.schema.document.SDField;
+import com.yahoo.vespa.indexinglanguage.ExpressionConverter;
+import com.yahoo.vespa.indexinglanguage.expressions.Expression;
+import com.yahoo.vespa.indexinglanguage.expressions.InputExpression;
+import com.yahoo.vespa.indexinglanguage.expressions.OutputExpression;
+import com.yahoo.vespa.model.container.search.QueryProfiles;
+
+/**
+ * @author Simon Thoresen Hult
+ */
+public class IndexingValues extends Processor {
+
+    public IndexingValues(Schema schema, DeployLogger deployLogger, RankProfileRegistry rankProfileRegistry, QueryProfiles queryProfiles) {
+        super(schema, deployLogger, rankProfileRegistry, queryProfiles);
+    }
+
+    @Override
+    public void process(boolean validate, boolean documentsOnly) {
+        if ( ! validate) return;
+
+        for (Field field : schema.getDocument().fieldSet()) {
+            SDField sdField = (SDField)field;
+            if ( ! sdField.isExtraField()) {
+                new RequireThatDocumentFieldsAreImmutable(field).convert(sdField.getIndexingScript());
+            }
+        }
+    }
+
+    private class RequireThatDocumentFieldsAreImmutable extends ExpressionConverter {
+
+        final Field field;
+        Expression mutatedBy;
+
+        RequireThatDocumentFieldsAreImmutable(Field field) {
+            this.field = field;
+        }
+
+        @Override
+        public ExpressionConverter branch() {
+            return clone();
+        }
+
+        @Override
+        protected boolean shouldConvert(Expression exp) {
+            if (exp instanceof OutputExpression && mutatedBy != null) {
+                throw newProcessException(schema, field,
+                                          "Indexing expression '" + mutatedBy + "' attempts to modify the value of the " +
+                                          "document field '" + field.getName() + "'. Use a field outside the document " +
+                                          "block instead.");
+            }
+            if (exp instanceof InputExpression && ((InputExpression)exp).getFieldName().equals(field.getName())) {
+                mutatedBy = null;
+            } else if (exp.createdOutputType() != null) {
+                mutatedBy = exp;
+            }
+            return false;
+        }
+
+        @Override
+        protected Expression doConvert(Expression exp) {
+            throw new UnsupportedOperationException();
+        }
+    }
+}