DataSchema.JSON Class
+ + + + +Provides a DataSchema implementation which can be used to work with JSON data.
+ +See the apply method for usage.
Item Index
+ + +Methods
+ +-
+
+
- + _getFieldValues + + + static + + + + +
- + _parseMeta + + + static + + + + +
- + _parseResults + + + static + + + + +
- + apply + + + static + + + + +
- + getLocationValue + + + static + + + + +
- + getPath + + + static + + + + +
- + parse + + + + + +
Methods
+ + +_getFieldValues
+
+
+ -
+
+
-
+
+
fields+ +
+
+ -
+
+
array_in+ +
+
+ -
+
+
data_out+ +
+
+
Get field data values out of list of full results
+Parameters:
+ + +Returns:
+ +_parseMeta
+
+
+ -
+
+
-
+
+
metaFields+ +
+
+ -
+
+
json_in+ +
+
+ -
+
+
data_out+ +
+
+
Parses results data according to schema
+Parameters:
+ + +Returns:
+ +_parseResults
+
+
+ -
+
+
-
+
+
schema+ +
+
+ -
+
+
json_in+ +
+
+ -
+
+
data_out+ +
+
+
Schema-parsed list of results from full data
+Parameters:
+ + +Returns:
+ +apply
+
+
+ -
+
+
-
+
+
[schema]+ +
+
+ -
+
+
data+ +
+
+
Applies a schema to an array of data located in a JSON structure, returning
+a normalized object with results in the results property. Additional
+information can be parsed out of the JSON for inclusion in the meta
+property of the response object. If an error is encountered during
+processing, an error property will be added.
The input data is expected to be an object or array. If it is a string,
+it will be passed through Y.JSON.parse().
If data contains an array of data records to normalize, specify the +schema.resultListLocator as a dot separated path string just as you would +reference it in JavaScript. So if your data object has a record array at +data.response.results, use schema.resultListLocator = +"response.results". Bracket notation can also be used for array indices or +object properties (e.g. "response['results']"); This is called a "path +locator"
+ +Field data in the result list is extracted with field identifiers in +schema.resultFields. Field identifiers are objects with the following +properties:
+ +-
+
key: (required) The path locator (String)
+parser: A function or the name of a function onY.Parsersused + to convert the input value into a normalized type. Parser + functions are passed the value as input and are expected to + return a value.
+
If no value parsing is needed, you can use path locators (strings) +instead of field identifiers (objects) -- see example below.
+ +If no processing of the result list array is needed, schema.resultFields
+can be omitted; the response.results will point directly to the array.
If the result list contains arrays, response.results will contain an
+array of objects with key:value pairs assuming the fields in
+schema.resultFields are ordered in accordance with the data array
+values.
If the result list contains objects, the identified schema.resultFields +will be used to extract a value from those objects for the output result.
+ +To extract additional information from the JSON, include an array of
+path locators in schema.metaFields. The collected values will be
+stored in response.meta.
Parameters:
+ +-
+
+
-
+
+
[schema]+ Object + optional + + + + +++ + +Schema to apply. Supported configuration + properties are:
+-
+
+
-
+
+
[resultListLocator]+ String + optional + + +++ + +Path locator for the + location of the array of records to flatten into
+response.results
+
+ -
+
+
[resultFields]+ Array + optional + + +++ + +Field identifiers to + locate/assign values in the response records. See above for + details.
+
+
+ -
+
+
[metaFields]+ Array + optional + + +++ + +Path locators to extract extra + non-record related information from the data object.
+
+
+
+
+ -
+
+
-
+
+
data+ Object | Array | String + + + + +++ + +JSON data or its string serialization.
+
+
+
Returns:
+ + +Example:
+ +// Process array of arrays
+var schema = {
+ resultListLocator: 'produce.fruit',
+ resultFields: [ 'name', 'color' ]
+ },
+ data = {
+ produce: {
+ fruit: [
+ [ 'Banana', 'yellow' ],
+ [ 'Orange', 'orange' ],
+ [ 'Eggplant', 'purple' ]
+ ]
+ }
+ };
+
+var response = Y.DataSchema.JSON.apply(schema, data);
+
+// response.results[0] is { name: "Banana", color: "yellow" }
+
+
+// Process array of objects + some metadata
+schema.metaFields = [ 'lastInventory' ];
+
+data = {
+ produce: {
+ fruit: [
+ { name: 'Banana', color: 'yellow', price: '1.96' },
+ { name: 'Orange', color: 'orange', price: '2.04' },
+ { name: 'Eggplant', color: 'purple', price: '4.31' }
+ ]
+ },
+ lastInventory: '2011-07-19'
+};
+
+response = Y.DataSchema.JSON.apply(schema, data);
+
+// response.results[0] is { name: "Banana", color: "yellow" }
+// response.meta.lastInventory is '2001-07-19'
+
+
+// Use parsers
+schema.resultFields = [
+ {
+ key: 'name',
+ parser: function (val) { return val.toUpperCase(); }
+ },
+ {
+ key: 'price',
+ parser: 'number' // Uses Y.Parsers.number
+ }
+];
+
+response = Y.DataSchema.JSON.apply(schema, data);
+
+// Note price was converted from a numeric string to a number
+// response.results[0] looks like { fruit: "BANANA", price: 1.96 }
+getLocationValue
+
+
+ -
+
+
-
+
+
path+ +
+
+ -
+
+
data+ +
+
+
Utility function to walk a path and return the value located there.
+Parameters:
+ + +Returns:
+ +getPath
+
+
+ -
+
+
-
+
+
locator+ +
+
+
Utility function converts JSON locator strings into walkable paths
+Parameters:
+ +-
+
+
-
+
+
locator+ String + + + + +++ + +JSON value locator.
+
+
+