Refactor expression commands for Jackson serialization

main/src/com/google/refine/commands/expr/GetExpressionHistoryCommand.java

@@ -37,19 +37,71 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Properties;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
+import org.json.JSONException;
 import org.json.JSONWriter;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+import com.google.refine.Jsonizable;
 import com.google.refine.ProjectManager;
 import com.google.refine.commands.Command;
 import com.google.refine.preference.TopList;
 
 public class GetExpressionHistoryCommand extends Command {
+    
+    public static class ExpressionState implements Jsonizable {
+        @JsonProperty("code")
+        protected String code;
+        @JsonProperty("global")
+        protected boolean global = false;
+        @JsonProperty("starred")
+        protected boolean starred;
+        
+        protected ExpressionState(String code, boolean starred) {
+            this.code = code;
+            this.starred = starred;
+        }
+
+        @Override
+        public void write(JSONWriter writer, Properties options)
+                throws JSONException {
+            writer.object();
+            writer.key("code"); writer.value(code);
+            writer.key("global"); writer.value(false);
+            writer.key("starred"); writer.value(starred);
+            writer.endObject();
+        }
+    }
+    
+    public static class ExpressionsList implements Jsonizable {
+        @JsonProperty("expressions")
+        List<ExpressionState> expressions;
+        
+        protected ExpressionsList(List<ExpressionState> states) {
+            this.expressions = states;
+        }
+
+        @Override
+        public void write(JSONWriter writer, Properties options)
+                throws JSONException {
+            writer.object();
+            writer.key("expressions");
+                writer.array();
+                for (ExpressionState e : expressions) {
+                    e.write(writer, options);
+                }
+                writer.endArray();
+            writer.endObject();
+        }
+    }
 
     static protected List<String> toExpressionList(Object o) {
         return o == null ? new ArrayList<String>() : ((TopList) o).getList();
@@ -60,40 +112,14 @@ public class GetExpressionHistoryCommand extends Command {
             throws ServletException, IOException {
         
         try {
-            List<String> localExpressions = toExpressionList(ProjectManager.singleton.getPreferenceStore().get("scripting.expressions"));
-            localExpressions = localExpressions.size() > 20 ? localExpressions.subList(0, 20) : localExpressions;
             
-            List<String> globalExpressions = toExpressionList(ProjectManager.singleton.getPreferenceStore().get("scripting.expressions"));
+            List<String> expressions = toExpressionList(ProjectManager.singleton.getPreferenceStore().get("scripting.expressions"));
             Set<String> starredExpressions = new HashSet<String>(((TopList)ProjectManager.singleton.getPreferenceStore().get("scripting.starred-expressions")).getList());
-            
+            ExpressionsList expressionsList = new ExpressionsList(expressions.stream()
-            Set<String> done = new HashSet<String>();
+                    .map(s -> new ExpressionState(s, starredExpressions.contains(s)))
-            
+                    .collect(Collectors.toList()));
-            response.setCharacterEncoding("UTF-8");
+      
-            response.setHeader("Content-Type", "application/json");
+            respondJSON(response, expressionsList);
-            
-            JSONWriter writer = new JSONWriter(response.getWriter());
-            writer.object();
-            writer.key("expressions");
-                writer.array();
-                for (String s : localExpressions) {
-                    writer.object();
-                    writer.key("code"); writer.value(s);
-                    writer.key("global"); writer.value(false);
-                    writer.key("starred"); writer.value(starredExpressions.contains(s));
-                    writer.endObject();
-                    done.add(s);
-                }
-                for (String s : globalExpressions) {
-                    if (!done.contains(s)) {
-                        writer.object();
-                        writer.key("code"); writer.value(s);
-                        writer.key("global"); writer.value(true);
-                        writer.key("starred"); writer.value(starredExpressions.contains(s));
-                        writer.endObject();
-                    }
-                }
-                writer.endArray();
-            writer.endObject();
         } catch (Exception e) {
             respondException(response, e);
         }

main/src/com/google/refine/commands/expr/GetExpressionLanguageInfoCommand.java

@@ -34,6 +34,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 package com.google.refine.commands.expr;
 
 import java.io.IOException;
+import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Properties;
 
@@ -41,8 +42,12 @@ import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
+import org.json.JSONException;
 import org.json.JSONWriter;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+import com.google.refine.Jsonizable;
 import com.google.refine.commands.Command;
 import com.google.refine.grel.Control;
 import com.google.refine.grel.ControlFunctionRegistry;
@@ -50,23 +55,27 @@ import com.google.refine.grel.Function;
 
 public class GetExpressionLanguageInfoCommand extends Command {
     
-    @Override
+    public static class LanguageInfo implements Jsonizable {
-    public void doGet(HttpServletRequest request, HttpServletResponse response)
-            throws ServletException, IOException {
         
-        try {
+        @JsonProperty("functions")
-            response.setCharacterEncoding("UTF-8");
+        Map<String, Function> functions;
-            response.setHeader("Content-Type", "application/json");
+        @JsonProperty("controls")
-            
+        Map<String, Control> controls;
-            JSONWriter writer = new JSONWriter(response.getWriter());
+        
-            Properties options = new Properties();
+        public LanguageInfo() {
-            
+            functions = ControlFunctionRegistry.getFunctionMap();
+            controls = ControlFunctionRegistry.getControlMap();
+        }
+
+        @Override
+        public void write(JSONWriter writer, Properties options)
+                throws JSONException {
             writer.object();
             
             writer.key("functions");
             writer.object();
             {
-                for (Entry<String, Function> entry : ControlFunctionRegistry.getFunctionMapping()) {
+                for (Entry<String, Function> entry : functions.entrySet()) {
                     writer.key(entry.getKey());
                     entry.getValue().write(writer, options);
                 }
@@ -76,7 +85,7 @@ public class GetExpressionLanguageInfoCommand extends Command {
             writer.key("controls");
             writer.object();
             {
-                for (Entry<String, Control> entry : ControlFunctionRegistry.getControlMapping()) {
+                for (Entry<String, Control> entry : controls.entrySet()) {
                     writer.key(entry.getKey());
                     entry.getValue().write(writer, options);
                 }
@@ -84,6 +93,16 @@ public class GetExpressionLanguageInfoCommand extends Command {
             writer.endObject();
             
             writer.endObject();
+        }
+        
+    }
+    
+    @Override
+    public void doGet(HttpServletRequest request, HttpServletResponse response)
+            throws ServletException, IOException {
+        
+        try {
+            respondJSON(response, new LanguageInfo());
         } catch (Exception e) {
             respondException(response, e);
         }

main/src/com/google/refine/commands/expr/GetStarredExpressionsCommand.java

@@ -2,13 +2,19 @@ package com.google.refine.commands.expr;
 
 import java.io.IOException;
 import java.util.List;
+import java.util.Properties;
+import java.util.stream.Collectors;
 
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
+import org.json.JSONException;
 import org.json.JSONWriter;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+import com.google.refine.Jsonizable;
 import com.google.refine.ProjectManager;
 import com.google.refine.commands.Command;
 import com.google.refine.preference.TopList;
@@ -16,27 +22,52 @@ import com.google.refine.preference.TopList;
 
 public class GetStarredExpressionsCommand extends Command {
     
+    protected static class Expression implements Jsonizable {
+        @JsonProperty("code")
+        protected String code;
+        protected Expression(String c) {
+            code = c;
+        }
+        @Override
+        public void write(JSONWriter writer, Properties options)
+                throws JSONException {
+            writer.object();
+            writer.key("code"); writer.value(code);
+            writer.endObject();
+        }
+    }
+    
+    protected static class ExpressionList implements Jsonizable {
+        @JsonProperty("expressions")
+        protected List<Expression> expressions;
+        protected ExpressionList(List<Expression> e) {
+            expressions = e;
+        }
+        @Override
+        public void write(JSONWriter writer, Properties options)
+                throws JSONException {
+            writer.object();
+            writer.key("expressions");
+                writer.array();
+                for (Expression s : expressions) {
+                    s.write(writer, options);
+                }
+                writer.endArray();
+            writer.endObject();
+        }
+    }
+    
+    public static ExpressionList getExpressionsList() {
+        List<String> starredExpressions = ((TopList)ProjectManager.singleton.getPreferenceStore().get("scripting.starred-expressions")).getList();
+        return new ExpressionList(starredExpressions.stream().map(e -> new Expression(e)).collect(Collectors.toList()));
+    }
+    
     @Override
     public void doGet(HttpServletRequest request, HttpServletResponse response)
             throws ServletException, IOException {
         
         try {
-            List<String> starredExpressions = ((TopList)ProjectManager.singleton.getPreferenceStore().get("scripting.starred-expressions")).getList();
+            respondJSON(response, getExpressionsList());
-            
-            response.setCharacterEncoding("UTF-8");
-            response.setHeader("Content-Type", "application/json");
-            
-            JSONWriter writer = new JSONWriter(response.getWriter());
-            writer.object();
-            writer.key("expressions");
-                writer.array();
-                for (String s : starredExpressions) {
-                    writer.object();
-                    writer.key("code"); writer.value(s);
-                    writer.endObject();
-                }
-                writer.endArray();
-            writer.endObject();
         } catch (Exception e) {
             respondException(response, e);
         }

main/src/com/google/refine/commands/expr/LogExpressionCommand.java

@@ -41,7 +41,6 @@ import javax.servlet.http.HttpServletResponse;
 
 import com.google.refine.ProjectManager;
 import com.google.refine.commands.Command;
-import com.google.refine.model.Project;
 import com.google.refine.preference.TopList;
 
 public class LogExpressionCommand extends Command {
@@ -51,7 +50,6 @@ public class LogExpressionCommand extends Command {
             throws ServletException, IOException {
         
         try {
-            Project project = getProject(request);
             String expression = request.getParameter("expression");
             
             ((TopList) ProjectManager.singleton.getPreferenceStore().get("scripting.expressions"))

main/src/com/google/refine/commands/expr/PreviewExpressionCommand.java

@@ -36,6 +36,7 @@ package com.google.refine.commands.expr;
 import java.io.IOException;
 import java.io.Serializable;
 import java.time.OffsetDateTime;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Properties;
 
@@ -48,6 +49,12 @@ import org.json.JSONException;
 import org.json.JSONObject;
 import org.json.JSONWriter;
 
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonInclude.Include;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonValue;
+
+import com.google.refine.Jsonizable;
 import com.google.refine.commands.Command;
 import com.google.refine.expr.EvalError;
 import com.google.refine.expr.Evaluable;
@@ -64,6 +71,85 @@ import com.google.refine.util.ParsingUtilities;
 
 public class PreviewExpressionCommand extends Command {
     
+    protected static interface ExpressionValue extends Jsonizable { }
+    protected static class ErrorMessage implements ExpressionValue {
+        @JsonProperty("message")
+        protected String message;
+        public ErrorMessage(String m) {
+            message = m;
+        }
+        @Override
+        public void write(JSONWriter writer, Properties options)
+                throws JSONException {
+            writer.object();
+            writer.key("message"); writer.value(message);
+            writer.endObject();
+        }
+        
+    }
+    protected static class SuccessfulEvaluation implements ExpressionValue {
+        @JsonValue
+        protected String value;
+        protected SuccessfulEvaluation(String value) {
+            this.value = value;
+        }
+        @Override
+        public void write(JSONWriter writer, Properties options)
+                throws JSONException {
+            writer.value(value);
+        }
+        
+    }
+    
+    protected static class PreviewResult implements Jsonizable {
+        @JsonProperty("code")
+        protected String code;
+        @JsonProperty("message")
+        @JsonInclude(Include.NON_NULL)
+        protected String message;
+        @JsonProperty("type")
+        @JsonInclude(Include.NON_NULL)
+        protected String type;
+        @JsonProperty("results")
+        List<ExpressionValue> results; 
+        
+        public PreviewResult(String code, String message, String type) {
+            this.code = code;
+            this.message = message;
+            this.type = type;
+            this.results = null;
+        }
+
+        public PreviewResult(List<ExpressionValue> evaluated) {
+            this.code = "ok";
+            this.message = null;
+            this.type = null;
+            this.results = evaluated;
+        }
+
+        @Override
+        public void write(JSONWriter writer, Properties options)
+                throws JSONException {
+            writer.object();
+            writer.key("code"); writer.value(code);
+            if(message != null) {
+                writer.key("message"); writer.value(message);
+            }
+            if(type != null) {
+                writer.key("type"); writer.value(type);
+            }
+            if(results != null) {
+                writer.key("results");
+                writer.array();
+                for(ExpressionValue v : results) {
+                    v.write(writer, options);
+                }
+                writer.endArray();
+            }
+            writer.endObject();
+        }
+    }
+    
     @Override
     public void doPost(HttpServletRequest request, HttpServletResponse response)
             throws ServletException, IOException {
@@ -77,7 +163,7 @@ public class PreviewExpressionCommand extends Command {
             String expression = request.getParameter("expression");
             String rowIndicesString = request.getParameter("rowIndices");
             if (rowIndicesString == null) {
-                respond(response, "{ \"code\" : \"error\", \"message\" : \"No row indices specified\" }");
+                respondJSON(response, new PreviewResult("error", "No row indices specified", null));
                 return;
             }
             
@@ -91,21 +177,13 @@ public class PreviewExpressionCommand extends Command {
                 }
             }
             
-            response.setCharacterEncoding("UTF-8");
-            response.setHeader("Content-Type", "application/json");
-            
             JSONArray rowIndices = ParsingUtilities.evaluateJsonStringToArray(rowIndicesString);
             int length = rowIndices.length();
             
-            JSONWriter writer = new JSONWriter(response.getWriter());
-            writer.object();
-            
             try {
                 Evaluable eval = MetaParser.parse(expression);
                 
-                writer.key("code"); writer.value("ok");
+                List<ExpressionValue> evaluated = new ArrayList<>();
-                writer.key("results"); writer.array();
-                
                 Properties bindings = ExpressionUtils.createBindings(project);
                 for (int i = 0; i < length; i++) {
                     Object result = null;
@@ -140,31 +218,23 @@ public class PreviewExpressionCommand extends Command {
                     }
                     
                     if (result == null) {
-                        writer.value(null);
+                        evaluated.add(null);
                     } else if (ExpressionUtils.isError(result)) {
-                        writer.object();
+                        evaluated.add(new ErrorMessage(((EvalError) result).message));
-                        writer.key("message"); writer.value(((EvalError) result).message);
-                        writer.endObject();
                     } else {
                         StringBuffer sb = new StringBuffer();
                         
                         writeValue(sb, result, false);
                         
-                        writer.value(sb.toString());
+                        evaluated.add(new SuccessfulEvaluation(sb.toString()));
                     }
                 }
-                writer.endArray();
+                respondJSON(response, new PreviewResult(evaluated));
             } catch (ParsingException e) {
-                writer.key("code"); writer.value("error");
+                respondJSON(response, new PreviewResult("error", e.getMessage(), "parser"));
-                writer.key("type"); writer.value("parser");
-                writer.key("message"); writer.value(e.getMessage());
             } catch (Exception e) {
-                writer.key("code"); writer.value("error");
+                respondJSON(response, new PreviewResult("error", e.getMessage(), "other"));
-                writer.key("type"); writer.value("other");
-                writer.key("message"); writer.value(e.getMessage());
             }
-            
-            writer.endObject();
         } catch (Exception e) {
             respondException(response, e);
         }

main/src/com/google/refine/commands/expr/ToggleStarredExpressionCommand.java

@@ -7,8 +7,6 @@ import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-import org.json.JSONWriter;
-
 import com.google.refine.ProjectManager;
 import com.google.refine.commands.Command;
 import com.google.refine.preference.TopList;
@@ -30,21 +28,7 @@ public class ToggleStarredExpressionCommand extends Command {
 
         if(request.getParameter("returnList") != null) {
             try {
-                response.setCharacterEncoding("UTF-8");
+                respondJSON(response, GetStarredExpressionsCommand.getExpressionsList());
-                response.setHeader("Content-Type", "application/json");
-
-                JSONWriter writer = new JSONWriter(response.getWriter());
-                writer.object();
-                writer.key("expressions");
-                writer.array();
-                for (String s : starredExpressions) {
-                    writer.object();
-                    writer.key("code");
-                    writer.value(s);
-                    writer.endObject();
-                }
-                writer.endArray();
-                writer.endObject();
             } catch (Exception e) {
                 respondException(response, e);
             }

main/src/com/google/refine/grel/ControlFunctionRegistry.java

@@ -33,6 +33,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 package com.google.refine.grel;
 
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -168,6 +169,9 @@ public class ControlFunctionRegistry {
     static public Set<Entry<String, Function>> getFunctionMapping() {
         return s_nameToFunction.entrySet();
     }
+    static public Map<String,Function> getFunctionMap() {
+        return Collections.unmodifiableMap(s_nameToFunction);
+    }
 
     static public Control getControl(String name) {
         return s_nameToControl.get(name);
@@ -178,6 +182,9 @@ public class ControlFunctionRegistry {
     static public Set<Entry<String, Control>> getControlMapping() {
         return s_nameToControl.entrySet();
     }
+    static public Map<String,Control> getControlMap() {
+        return Collections.unmodifiableMap(s_nameToControl);
+    }
 
     static public void registerFunction(String name, Function f) {
         s_nameToFunction.put(name, f);