stevedlawrence commented on a change in pull request #273: WIP: Add User 
Defined Functions Capability
URL: https://github.com/apache/incubator-daffodil/pull/273#discussion_r331574446
 
 

 ##########
 File path: 
daffodil-runtime1/src/main/java/org/apache/daffodil/udf/UDFunctionService.java
 ##########
 @@ -0,0 +1,137 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.daffodil.udf;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.ServiceConfigurationError;
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.ServiceLoader;
+import java.util.stream.Collectors;
+
+import org.apache.daffodil.util.Misc;
+
+public class UDFunctionService {
+       private ServiceLoader<UDFunctionProvider> loader;
+       private ArrayList<Class<?>> functionClasses = new ArrayList<>();
+       private HashMap<String, UDFunctionProvider> functionProviderLookup = 
new HashMap<>();
+       private ArrayList<String> errors = new ArrayList<>();
+       private ArrayList<String> warnings = new ArrayList<>();
+
+       public UDFunctionService(ClassLoader cl) {
+               try {
+                       loader = cl == null ? 
ServiceLoader.load(UDFunctionProvider.class) : 
ServiceLoader.load(UDFunctionProvider.class, cl);
+
+                       loader.forEach(fcp -> {
+                               Class<?>[] fcpfc = fcp.getFunctionClasses();
+
+                               if (fcpfc == null || fcpfc.length == 0) {
+                                       warnings.add(String.format("Provider 
ignored: [%s].\nNo Function Classes found.",
+                                                       
fcp.getClass().getName()));
+                                       return;
+                               }
+
+                               List<Class<?>> fc = Arrays.asList(fcpfc);
+
+                               List<Class<?>> missingAnnotations = fc.stream()
+                                               .filter(f -> 
!f.isAnnotationPresent(FunctionClassInfo.class)).collect(Collectors.toList());
+
+                               List<Class<?>> nonSerializables = 
fc.stream().filter(f -> Serializable.class.isAssignableFrom(f))
+                                               .collect(Collectors.toList());
+
+                               if (!missingAnnotations.isEmpty()) {
+                                       warnings.add(
+                                                       String.format("Provider 
ignored: [%s].\nAnnotations missing for FunctionClass(es):\n%s",
+                                                                       
fcp.getClass().getName(), missingAnnotations.stream().map(c -> c.getName())
+                                                                               
        .collect(Collectors.joining("\n", "\t[", "]"))));
+                                       return;
+                               }
+
+                               if (!nonSerializables.isEmpty()) {
+                                       warnings.add(String.format(
+                                                       "Provider ignored: 
[%s].\nFunctionClass(es) must implement java.io.Serializable:\n%s",
+                                                       
fcp.getClass().getName(), nonSerializables.stream().map(c -> c.getName())
+                                                                       
.collect(Collectors.joining("\n", "\t[", "]"))));
+                                       return;
+                               }
+
+                               fc.stream().forEach(f -> {
+                                       FunctionClassInfo fInfo = 
f.getAnnotation(FunctionClassInfo.class);
+                                       String ns = fInfo.namespace();
+                                       String fname = fInfo.name();
+                                       if (ns.isEmpty() || fname.isEmpty() || 
ns.matches("\\s+") || fname.matches("\\s+")) {
+                                               
warnings.add(String.format("FunctionClass ignored: [%s]. From Provider 
[%s].%s%s", f.getName(), fcp.getClass().getName(),
+                                                               ns.isEmpty() ? 
"\nAnnotation namespace field is empty or invalid." : "",
+                                                               fname.isEmpty() 
? "\nAnnotation name field is empty or invalid." : ""));
+                                       }
+
+                                       String key = String.join("_", 
fInfo.namespace(), fInfo.name());
+                                       if 
(functionProviderLookup.containsKey(key)) {
+                                               warnings.add(String.format(
+                                                               "FunctionClass 
ignored: [%s].\nDuplicate name [%s] and namespace[%s] found.",
+                                                               f.getName(), 
key.split("_")[0], key.split("_")[1]));
+                                       } else {
+                                               functionProviderLookup.put(key, 
fcp);
+                                               functionClasses.add(f);
+                                       }
+                               });
+                       });
+
+                       if (functionClasses.isEmpty()) {
+                               errors.add(String.format("No user defined 
functions found."
+                                               + "\nCheck that UDF JARs are on 
classpath and that they are properly registerable by ServiceLoader."
+                                               + "\nCurrent classpath 
locations:\n%s",
+                                               
Arrays.asList(Misc.getClassPath()).stream().map(u -> u.toString())
+                                                               
.collect(Collectors.joining("\n"))));
+                       }
+               } catch (ServiceConfigurationError | Exception e) {
+                       e.printStackTrace();
+                       errors.add(e.toString() + String.format("\nCurrent 
classpath locations:\n%s", Arrays
+                                       
.asList(Misc.getClassPath()).stream().map(u -> 
u.toString()).collect(Collectors.joining("\n"))));
+               }
+       }
+
+       public Object lookupFunctionClass(String namespace, String name) {
+               Object funcObj = null;
+
+               try {
+                       UDFunctionProvider fp = 
this.functionProviderLookup.get(String.join("_", namespace, name));
+                       if (fp != null) {
+                               funcObj = fp.lookupFunctionClass(namespace, 
name);
 
 Review comment:
   A thought, if a UDFProvider implemented their lookupFunctionClass function 
poorly, they could return an instance class that doesn't match what we had 
already validated, because we only validated what getFunctionClasses returns. 
Should we also validate here that the thing returned is the same class that we 
validated earlier?

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


With regards,
Apache Git Services

Reply via email to