1 files changed, 139 insertions, 0 deletions
diff --git a/config-model/src/main/java/com/yahoo/schema/expressiontransforms/OnnxModelTransformer.java b/config-model/src/main/java/com/yahoo/schema/expressiontransforms/OnnxModelTransformer.java
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+++ b/config-model/src/main/java/com/yahoo/schema/expressiontransforms/OnnxModelTransformer.java
@@ -0,0 +1,139 @@
+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.schema.expressiontransforms;
+
+import com.yahoo.path.Path;
+import com.yahoo.schema.OnnxModel;
+import com.yahoo.schema.RankProfile;
+import com.yahoo.searchlib.rankingexpression.Reference;
+import com.yahoo.searchlib.rankingexpression.rule.Arguments;
+import com.yahoo.searchlib.rankingexpression.rule.CompositeNode;
+import com.yahoo.searchlib.rankingexpression.rule.ConstantNode;
+import com.yahoo.searchlib.rankingexpression.rule.ExpressionNode;
+import com.yahoo.searchlib.rankingexpression.rule.ReferenceNode;
+import com.yahoo.searchlib.rankingexpression.transform.ExpressionTransformer;
+import com.yahoo.vespa.model.ml.ConvertedModel;
+import com.yahoo.vespa.model.ml.FeatureArguments;
+import com.yahoo.vespa.model.ml.ModelName;
+
+import java.util.List;
+
+/**
+ * Transforms ONNX model features of the forms:
+ *
+ *     onnxModel(config_name)
+ *     onnxModel(config_name).output
+ *     onnxModel("path/to/model")
+ *     onnxModel("path/to/model").output
+ *     onnxModel("path/to/model", "path/to/output")
+ *     onnxModel("path/to/model", "unused", "path/to/output")    // signature is unused
+ *     onnx(...)   // same as with onnxModel, onnx is an alias of onnxModel
+ *
+ * To the format expected by the backend:
+ *
+ *     onnxModel(config_name).output
+ *
+ * @author lesters
+ */
+public class OnnxModelTransformer extends ExpressionTransformer<RankProfileTransformContext> {
+
+    @Override
+    public ExpressionNode transform(ExpressionNode node, RankProfileTransformContext context) {
+        if (node instanceof ReferenceNode)
+            return transformFeature((ReferenceNode) node, context);
+        else if (node instanceof CompositeNode)
+            return super.transformChildren((CompositeNode) node, context);
+        else
+            return node;
+    }
+
+    private ExpressionNode transformFeature(ReferenceNode feature, RankProfileTransformContext context) {
+        if (context.rankProfile() == null) return feature;
+        if (context.rankProfile().schema() == null) return feature;
+        return transformFeature(feature, context.rankProfile());
+    }
+
+    public static ExpressionNode transformFeature(ReferenceNode feature, RankProfile profile) {
+        String featureName = feature.getName();
+        if ( ! featureName.equals("onnxModel") && ! featureName.equals("onnx")) return feature;
+
+        Arguments arguments = feature.getArguments();
+        if (arguments.isEmpty())
+            throw new IllegalArgumentException("An " + featureName + " feature must take an argument referring to a " +
+                                               "onnx-model config or an ONNX file.");
+        if (arguments.expressions().size() > 3)
+            throw new IllegalArgumentException("An " + featureName + " feature can have at most 3 arguments.");
+
+        // Check that the model configuration "onnx-model" exists. If not defined, it should have been added
+        // by the "OnnxModelConfigGenerator" processor. If it still doesn't exist, it is because we can't find
+        // the actual ONNX file, which can happen if we are restarting or upgrading an application using an
+        // ONNX file that was transformed to Vespa ranking expressions. We then assume it is in the model store.
+
+        String modelConfigName = getModelConfigName(feature.reference());
+        OnnxModel onnxModel = profile.onnxModels().get(modelConfigName);
+        if (onnxModel == null) {
+            String path = asString(arguments.expressions().get(0));
+            ModelName modelName = new ModelName(null, Path.fromString(path), true);
+            ConvertedModel convertedModel = ConvertedModel.fromStore(profile.schema().applicationPackage(), modelName, path, profile);
+            FeatureArguments featureArguments = new FeatureArguments(arguments);
+            return convertedModel.expression(featureArguments, null);
+        }
+
+        String defaultOutput = onnxModel.getOutputMap().get(onnxModel.getDefaultOutput());
+        String output = getModelOutput(feature.reference(), defaultOutput);
+        if (! onnxModel.getOutputMap().containsValue(output)) {
+            throw new IllegalArgumentException(featureName + " argument '" + output +
+                                               "' output not found in model '" + onnxModel.getFileName() + "'");
+        }
+        return new ReferenceNode("onnxModel", List.of(new ReferenceNode(modelConfigName)), output);
+    }
+
+    public static String getModelConfigName(Reference reference) {
+        if (reference.arguments().size() > 0) {
+            ExpressionNode expr = reference.arguments().expressions().get(0);
+            if (expr instanceof ReferenceNode) {  // refers to onnx-model config
+                return expr.toString();
+            }
+            if (expr instanceof ConstantNode) {  // refers to a file path
+                return asValidIdentifier(expr);
+            }
+        }
+        return null;
+    }
+
+    public static String getModelOutput(Reference reference, String defaultOutput) {
+        if (reference.output() != null) {
+            return reference.output();
+        } else if (reference.arguments().expressions().size() == 2) {
+            return asValidIdentifier(reference.arguments().expressions().get(1));
+        } else if (reference.arguments().expressions().size() > 2) {
+            return asValidIdentifier(reference.arguments().expressions().get(2));
+        }
+        return defaultOutput;
+    }
+
+    public static String stripQuotes(String s) {
+        if (isNotQuoteSign(s.codePointAt(0))) return s;
+        if (isNotQuoteSign(s.codePointAt(s.length() - 1)))
+            throw new IllegalArgumentException("argument [" + s + "] is missing end quote");
+        return s.substring(1, s.length()-1);
+    }
+
+    public static String asValidIdentifier(String str) {
+        return str.replaceAll("[^\\w\\d\\$@_]", "_");
+    }
+
+    private static String asValidIdentifier(ExpressionNode node) {
+        return asValidIdentifier(asString(node));
+    }
+
+    private static boolean isNotQuoteSign(int c) {
+        return c != '\'' && c != '"';
+    }
+
+    public static String asString(ExpressionNode node) {
+        if ( ! (node instanceof ConstantNode))
+            throw new IllegalArgumentException("Expected a constant string as argument, but got '" + node);
+        return stripQuotes(node.toString());
+    }
+
+}