refactoring costco to support bulk deletions and better functional transform error handling

attachments/script/costco.js

@@ -3,60 +3,117 @@
 var costco = function() {
 
   function handleEditorChange(e) {
-    mapDocs(app.cache, e.target.value, true);
-  }
-
-  function mapDocs(docs, funcString, preview) {
-    if(preview) var errors = $('.expression-preview-parsing-status');
-    try {
-      eval("var editFunc = " + funcString);
-      if(preview) errors.text('No syntax error.');
-    } catch(e) {
-      if(preview) errors.text(e+"");
+    var editFunc = evalFunction(e.target.value);
+    var errors = $('.expression-preview-parsing-status');
+    if (_.isFunction(editFunc)) {
+      errors.text('No syntax error.');
+    } else {
+      errors.text(editFunc);
       return;
     }
+    previewTransform(app.cache, editFunc);
+  }
+  
+  function evalFunction(funcString) {
+    try {
+      eval("var editFunc = " + funcString);
+      return editFunc;
+    } catch(e) {
+      return e+"";
+    }
+  }
+  
+  function previewTransform(docs, editFunc) {
+    var preview = [];
+    var updated = mapDocs(docs, editFunc);
+    for (var i = 0; i < updated.docs.length; i++) {      
+      var before = docs[i]
+        , after = updated.docs[i]
+        ;
+      if (!after) after = {};
+      preview.push({before: JSON.stringify(before[app.currentColumn]), after: JSON.stringify(after[app.currentColumn])});      
+    }
+    util.render('editPreview', 'expression-preview-container', {rows: preview});
+  }
 
-    var toUpdate = []
-      , deleted = 0
-      , edited = 0
-      , failed = 0
+  function mapDocs(docs, editFunc) {
+    var edited = []
+      , deleted = []
+      , failed = []
       ;
     
-    if(preview) var preview = [];
-      
-    _.each(docs, function(doc) {
+    var updatedDocs = _.map(docs, function(doc) {
       try {
         var updated = editFunc(_.clone(doc));
       } catch(e) {
-        failed++; // ignore if it throws on this doc
+        failed.push(doc);
         return;
       }
       if(updated === null) {
-        doc._deleted = true;
-        toUpdate.push(doc);
-        deleted++;
+        updated = {_deleted: true};
+        edited.push(updated);
+        deleted.push(doc);
       }
       else if(updated && !_.isEqual(updated, doc)) {
-        toUpdate.push(updated);
-        edited++;
+        edited.push(updated);
       }
-      
-      if(preview) preview.push({before: JSON.stringify(doc[app.currentColumn]), after: JSON.stringify(updated[app.currentColumn])});
+      return updated;      
     });
     
-    if(preview) util.render('editPreview', 'expression-preview-container', {rows: preview});
-    return toUpdate;
+    return {
+      edited: edited, 
+      docs: updatedDocs, 
+      deleted: deleted, 
+      failed: failed
+    };
+  }
+  
+  function updateDocs(editFunc) {
+    var dfd = $.Deferred();
+    util.notify("Updating documents...", {persist: true, loader: true});
+    couch.request({url: app.baseURL + "api/json"}).then(function(docs) {
+      var toUpdate = costco.mapDocs(docs.docs, editFunc).edited;
+      costco.uploadDocs(toUpdate).then(
+        function(updatedDocs) { 
+          util.notify(updatedDocs.length + " documents updated successfully");
+          recline.fetchRows(false, app.offset);
+          dfd.resolve(updatedDocs);
+        },
+        function(err) {
+          util.notify("Errorz! " + err);
+          dfd.reject(err);
+        }
+      );
+    });
+    return dfd.promise();
   }
 
-  function updateDocs(docs, callback) {
-    if(!docs.length)
-      return callback("Failed to update");    
-    couch.request({url: app.baseURL + "api/_bulk_docs", type: "POST", data: JSON.stringify({docs: docs})}).then(callback);
+  function uploadDocs(docs) {
+    var dfd = $.Deferred();
+    if(!docs.length) dfd.resolve("Failed to update");
+    couch.request({url: app.baseURL + "api/_bulk_docs", type: "POST", data: JSON.stringify({docs: docs})})
+      .then(
+        dfd.resolve, 
+        function(err) { dfd.reject(err.responseText) }
+      );
+    return dfd.promise();
+  }
+  
+  function deleteColumn(name) {
+    var deleteFunc = function(doc) {
+      delete doc[name];
+      return doc;
+    }
+    return updateDocs(deleteFunc);
   }
 
   return {
     handleEditorChange: handleEditorChange,
+    evalFunction: evalFunction,
+    previewTransform: previewTransform,
     mapDocs: mapDocs,
-    updateDocs: updateDocs
+    updateDocs: updateDocs,
+    uploadDocs: uploadDocs,
+    deleteColumn: deleteColumn
   };
 }();