Feature/issue216

grails-app/assets/javascripts/forms-knockout-bindings.js

@@ -679,7 +679,10 @@
  var options = _.defaults(valueAccessor() || {}, defaults);
 
  $(element).select2(options).change(function(e) {
- model($(element).val());
+ if (ko.isWritableObservable(model)) { // Don't try and write the value to a computed.
+ model($(element).val());
+ }
+
  });
 
  if (options.preserveColumnWidth) {
@@ -1173,7 +1176,54 @@
  });
  }); // This is a computed rather than a pureComputed as it has a side effect.
  return target;
- }
+ };
+
+ ko.bindingHandlers['triggerPrePopulate'] = {
+ 'update': function (element, valueAccessor, allBindings, viewModel, bindingContext) {
+
+
+ var dataModelItem = valueAccessor();
+ var behaviours = dataModelItem.get('behaviour');
+ for (var i = 0; i < behaviours.length; i++) {
+ var behaviour = behaviours[i];
+
+ if (behaviour.type == 'pre_populate') {
+ var config = behaviour.config;
+ var dataLoaderContext = dataModelItem.context;
+
+ var dataLoader = new ecodata.forms.dataLoader(dataLoaderContext, dataModelItem.config);
+
+ var dependencyTracker = ko.computed(function () {
+ dataModelItem(); // register dependency on the observable.
+ dataLoader.prepop(config).done(function (data) {
+ data = data || {};
+ var target = config.target;
+ if (!target) {
+ target = viewModel;
+ }
+ else {
+ target = dataModelItem.findNearestByName(target, bindingContext);
+ }
+ if (!target) {
+ throw "Unable to locate target for pre-population: "+target;
+ }
+ if (_.isFunction(target.loadData)) {
+ target.loadData(data);
+ } else if (_.isFunction(target.load)) {
+ target.load(data);
+ } else if (ko.isObservable(target)) {
+ target(data);
+ } else {
+ console.log("Warning: target for pre-populate is invalid");
+ }
+
+ }); // This is a computed rather than a pureComputed as it has a side effect.
+ });
+ }
+ }
+
+ }
+ };
 
 })();
 

grails-app/assets/javascripts/forms.js

@@ -179,6 +179,49 @@ function orEmptyArray(v) {
  }
  };
 
+ /**
+ * Traverses the model or binding context starting from a nested context and
+ * working backwards towards the root until a property with the supplied name
+ * is matched. That property is then passed to the supplied callback.
+ * Traversing backwards is simpler than forwards as we don't need to take into
+ * account repeating model values (e.g. for repeating sections and table rows)
+ * @param targetName the name of the model variable / property to find.
+ * @param context the starting context
+ * @param callback a function to invoke when the target variable is found.
+ */
+ ecodata.forms.navigateModel = function(targetName, context, callback) {
+ if (!context) {
+ return;
+ }
+ if (!_.isUndefined(context[targetName])) {
+ callback(context[targetName]);
+ }
+ // If the context is a knockout binding context, $data will be the current object
+ // being bound to the view.
+ else if (context['$data']) {
+ ecodata.forms.navigateModel(targetName, context['$data'], callback);
+ }
+ // The root data model is constructed with fields inside a nested "data" object.
+ else if (_.isObject(context['data'])) {
+ ecodata.forms.navigateModel(targetName, context['data'], callback);
+ }
+ // Try to evaluate against the parent - the bindingContext uses $parent and the
+ // ecodata.forms.DataModelItem uses parent
+ else if (context['$parent']) {
+ ecodata.forms.navigateModel(targetName, context['$parent'], callback);
+ }
+ else if (context['parent']) {
+ ecodata.forms.navigateModel(targetName, context['parent'], callback);
+ }
+ // Try to evaluate against the context - this is setup as a model / binding context
+ // variable and refers to data external to the form - e.g. the project or activity the
+ // form is related to.
+ else if (context['$context']) {
+ ecodata.forms.navigateModel(targetName, context['$context'], callback);
+ }
+
+ }
+
  /**
  * Helper function for evaluating expressions defined in the metadata. These may be used to compute values
  * or make decisions on which constraints to apply to individual data model items.
@@ -253,6 +296,10 @@ function orEmptyArray(v) {
  return _.findWhere(list, obj);
  };
 
+ parser.functions.deepEquals = function(value1, value2) {
+ return _.isEqual(value1, value2);
+ };
+
  var specialBindings = function() {
 
  return {
@@ -296,27 +343,9 @@ function orEmptyArray(v) {
  result = specialBindings[contextVariable];
  }
  else {
- if (!_.isUndefined(context[contextVariable])) {
- result = ko.utils.unwrapObservable(context[contextVariable]);
- }
- else {
- // The root view model is constructed with fields inside a nested "data" object.
- if (_.isObject(context['data'])) {
- result = bindVariable(variable, context['data']);
- }
- // Try to evaluate against the parent
- else if (context['$parent']) {
- // If the parent is the output model, we want to evaluate against the "data" property
- var parentContext = _.isObject(context['$parent'].data) ? context['$parent'].data : context['$parent'];
- result = bindVariable(variable, parentContext);
- }
- // Try to evaluate against the context - used when we are evaluating pre-pop data with a filter
- // expression that references a variable in the form context
- else if (context['$context']) {
- result = bindVariable(variable, context['$context']);
- }
- }
-
+ ecodata.forms.navigateModel(contextVariable, context, function(target) {
+ result = ko.utils.unwrapObservable(target);
+ });
  }
  return _.isUndefined(result) ? null : result;
  }
@@ -334,14 +363,14 @@ function orEmptyArray(v) {
  var expressionCache = {};
 
  function evaluateInternal(expression, context) {
-  var parsedExpression = expressionCache[expression];
-  if (!parsedExpression) {
-  parsedExpression = parser.parse(expression);
-  expressionCache[expression] = parsedExpression;
-  }
+ var parsedExpression = expressionCache[expression];
+ if (!parsedExpression) {
+ parsedExpression = parser.parse(expression);
+ expressionCache[expression] = parsedExpression;
+ }
 
-  var variables = parsedExpression.variables();
-  var boundVariables = bindVariables(variables, context);
+ var variables = parsedExpression.variables();
+ var boundVariables = bindVariables(variables, context);
 
  var result;
  try {
@@ -619,16 +648,32 @@ function orEmptyArray(v) {
  if (prepopData) {
  var result = prepopData;
  var mapping = conf.mapping;
- if (conf.filter && conf.filter.expression) {
- if (!_.isArray(prepopData)) {
- throw "Filtering is only supported for array typed prepop data."
+
+ function postProcessPrepopData(processingFunction, processingConfig, data) {
+ if (!_.isArray(data)) {
+ throw "Filter/find is only supported for array typed prepop data."
  }
- result = _.filter(result, function(item) {
- var expression = conf.filter.expression;
- var itemContext = _.extend({}, item, {$context:context, $config:config});
- return ecodata.forms.expressionEvaluator.evaluateBoolean(expression, itemContext);
+ if (!processingConfig.expression) {
+ throw "Missing expression attribute in configuration"
+ }
+ return processingFunction(data, function(item) {
+ var expression = processingConfig.expression;
+ var namespace = processingConfig['namespace'] || 'item';
+ var evalContext = {};
+ evalContext[namespace] = item;
+
+ var evalContext = _.extend(evalContext, {$context:context, $config:config});
+ return ecodata.forms.expressionEvaluator.evaluateBoolean(expression, evalContext);
  });
  }
+
+ if (conf.filter) {
+ result = postProcessPrepopData(_.filter, conf.filter, result);
+ }
+ else if (conf.find) {
+ result = postProcessPrepopData(_.find, conf.find, result);
+ }
+
  if (mapping) {
  result = self.map(mapping, result);
  }
@@ -796,16 +841,46 @@ function orEmptyArray(v) {
  function buildPrepopConstraints(constraintsConfig, constraintsDeferred) {
  var defaultConstraints = constraintsConfig.defaults || [];
  var constraintsObservable = ko.observableArray(defaultConstraints);
-
- return ko.computed(function() {
- var dataLoaderContext = _.extend({}, context, {$parent:context.parent});
- var dataLoader = ecodata.forms.dataLoader(dataLoaderContext, config);
- dataLoader.prepop(constraintsConfig.config).done(function (data) {
+ var dataLoaderContext = _.extend({}, context, {$parent:context.parent});
+ var dataLoader = ecodata.forms.dataLoader(dataLoaderContext, config);
+
+ ko.computed(function() {
+ var prepopConf = constraintsConfig.config;
+ // If the prepop needs to post process the data, we need to execute the post processing
+ // in the context of the computed so as to register any dependencies on values used in
+ // the post-processing expressions.
+ // The dataloader won't execute post processing synchronously as retrieving the data can be done
+ // via a remote call.
+ if (prepopConf.filter) {
+ ecodata.forms.expressionEvaluator.evaluate(prepopConf.filter.expression, dataLoaderContext);
+ }
+ if (prepopConf.find) {
+ ecodata.forms.expressionEvaluator.evaluate(prepopConf.filter.expression, dataLoaderContext);
+ }
+ dataLoader.prepop(prepopConf).done(function (data) {
  constraintsObservable(data);
  constraintsDeferred.resolve();
  });
- return constraintsObservable();
  });
+
+ return constraintsObservable;
+ }
+
+ /**
+ * Finds the model attribute with the specified name searching from the context of this
+ * DataModelItem if no context is supplied.
+ * This is so that for nested items we can find the nearest neighbour with the specified name. (e.g.
+ * when the model represents a repeating section or table row)
+ */
+ self.findNearestByName = function(targetName, context) {
+ if (!context) {
+ context = self.context;
+ }
+ var result = null;
+ ecodata.forms.navigateModel(targetName, context, function(target) {
+ result = target;
+ })
+ return result;
  }
 
  function attachIncludeExclude(constraints) {

grails-app/conf/example_models/behavioursExample.json

@@ -31,6 +31,47 @@
  }
  }
  ]
+ },
+ {
+ "dataType": "text",
+ "name": "item5",
+ "behaviour": [
+ {
+ "config": {
+ "source": {
+ "url": "/preview/prepopulate",
+ "params": [
+ {
+ "name": "param",
+ "type": "computed",
+ "expression": "item5"
+ },
+ {
+ "name": "item5",
+ "type": "computed",
+ "expression": "item5"
+ }
+ ]
+ },
+ "mapping": [
+ {
+ "source-path": "param",
+ "target": "item6"
+ },
+ {
+ "source-path": "item5",
+ "target": "item5"
+ }
+ ],
+ "target": "$data"
+ },
+ "type": "pre_populate"
+ }
+ ]
+ },
+ {
+ "dataType": "text",
+ "name": "item6"
  }
  ],
  "viewModel": [
@@ -69,7 +110,40 @@
  "title": "Item 4"
  }
  ]
-
+ },
+ {
+ "type": "row",
+ "items": [
+ {
+ "type": "col",
+ "items": [
+ {
+ "type": "literal",
+ "source": "Note for this example, data entered into item5 will trigger a pre-pop call and be mapped back to item5 and item6. Note that the target of the pre-pop is $data which is the current binding context (or the root object in this case). A current limitation is the load method is used, which means if the pre-pop result does not contain keys for all data in the target object, the data for missing fields will be set to undefined. A planned enhancement is to only replace data where keys in the pre-pop data exist."
+ }
+ ]
+ }
+ ]
+ },
+ {
+ "type": "row",
+ "items": [
+ {
+ "type": "col",
+ "items": [
+ {
+ "preLabel": "Item 5",
+ "source": "item5",
+ "type": "text"
+ },
+ {
+ "preLabel": "Item 6",
+ "source": "item6",
+ "type": "text"
+ }
+ ]
+ }
+ ]
  }
  ],
  "title": "Behaviours example"

grails-app/conf/example_models/constraintsExample.json

@@ -20,7 +20,19 @@
  "type": "pre-populated",
  "config": {
  "source": {
- "url": "/preview/prepopulateConstraints"
+ "url": "/preview/prepopulateConstraints",
+ "params" : [
+ {
+ "name":"p1",
+ "value":"1"
+ },
+ {
+ "name": "p2",
+ "type": "computed",
+ "expression": "number1"
+ }
+
+ ]
  }
  },
  "excludePath": "list.value1"
@@ -65,7 +77,7 @@
  "items": [
  {
  "type": "literal",
- "source": "<p>This example illustrates the use of computed constraints</p><p>The 'Value 2' field will only allow each item in the dropdown to be selected once, no matter how many times 'Value 2' appears on the page.</p><p>For each selection made in a 'Value 2' field, that value will be added as a selectable option in the 'Value 3' field.</p>"
+ "source": "<p>This example illustrates the use of computed constraints</p><p>The 'Value 2' field will only allow each item in the dropdown to be selected once, no matter how many times 'Value 2' appears on the page.</p><p>For each selection made in a 'Value 2' field, that value will be added as a selectable option in the 'Value 3' field.</p><p>Note also that the constraints for 'value1' include a parameter that references a form variable. When that variable changes, the constraint pre-population is re-executed</p>"
  }
  ]
  },