Version 3.18.1
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File: dataschema/js/dataschema-text.js

            /**
             * Provides a DataSchema implementation which can be used to work with
             * delimited text data.
             *
             * @module dataschema
             * @submodule dataschema-text
             */
            
            /**
            Provides a DataSchema implementation which can be used to work with
            delimited text data.
            
            See the `apply` method for usage.
            
            @class DataSchema.Text
            @extends DataSchema.Base
            @static
            **/
            
            var Lang = Y.Lang,
                isString = Lang.isString,
                isUndef  = Lang.isUndefined,
            
                SchemaText = {
            
                    ////////////////////////////////////////////////////////////////////////
                    //
                    // DataSchema.Text static methods
                    //
                    ////////////////////////////////////////////////////////////////////////
                    /**
                    Applies a schema to a string of delimited data, returning a normalized
                    object with results in the `results` property. The `meta` property of
                    the response object is present for consistency, but is assigned an
                    empty object.  If the input data is absent or not a string, an `error`
                    property will be added.
            
                    Use _schema.resultDelimiter_ and _schema.fieldDelimiter_ to instruct
                    `apply` how to split up the string into an array of data arrays for
                    processing.
            
                    Use _schema.resultFields_ to specify the keys in the generated result
                    objects in `response.results`. The key:value pairs will be assigned
                    in the order of the _schema.resultFields_ array, assuming the values
                    in the data records are defined in the same order.
            
                    _schema.resultFields_ field identifiers are objects with the following
                    properties:
            
                      * `key`   : <strong>(required)</strong> The property name you want
                            the data value assigned to in the result object (String)
                      * `parser`: A function or the name of a function on `Y.Parsers` used
                            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 just the desired property
                    name string as the field identifier instead of an object (see example
                    below).
            
                    @example
                        // Process simple csv
                        var schema = {
                                resultDelimiter: "\n",
                                fieldDelimiter: ",",
                                resultFields: [ 'fruit', 'color' ]
                            },
                            data = "Banana,yellow\nOrange,orange\nEggplant,purple";
            
                        var response = Y.DataSchema.Text.apply(schema, data);
            
                        // response.results[0] is { fruit: "Banana", color: "yellow" }
            
            
                        // Use parsers
                        schema.resultFields = [
                            {
                                key: 'fruit',
                                parser: function (val) { return val.toUpperCase(); }
                            },
                            'color' // mix and match objects and strings
                        ];
            
                        response = Y.DataSchema.Text.apply(schema, data);
            
                        // response.results[0] is { fruit: "BANANA", color: "yellow" }
            
                    @method apply
                    @param {Object} schema Schema to apply.  Supported configuration
                        properties are:
                      @param {String} schema.resultDelimiter Character or character
                          sequence that marks the end of one record and the start of
                          another.
                      @param {String} [schema.fieldDelimiter] Character or character
                          sequence that marks the end of a field and the start of
                          another within the same record.
                      @param {Array} [schema.resultFields] Field identifiers to
                          assign values in the response records. See above for details.
                    @param {String} data Text data.
                    @return {Object} An Object with properties `results` and `meta`
                    @static
                    **/
                    apply: function(schema, data) {
                        var data_in = data,
                            data_out = { results: [], meta: {} };
            
                        if (isString(data) && schema && isString(schema.resultDelimiter)) {
                            // Parse results data
                            data_out = SchemaText._parseResults.call(this, schema, data_in, data_out);
                        } else {
                            Y.log("Text data could not be schema-parsed: " + Y.dump(data) + " " + Y.dump(data), "error", "dataschema-text");
                            data_out.error = new Error("Text schema parse failure");
                        }
            
                        return data_out;
                    },
            
                    /**
                     * Schema-parsed list of results from full data
                     *
                     * @method _parseResults
                     * @param schema {Array} Schema to parse against.
                     * @param text_in {String} Text to parse.
                     * @param data_out {Object} In-progress parsed data to update.
                     * @return {Object} Parsed data object.
                     * @static
                     * @protected
                     */
                    _parseResults: function(schema, text_in, data_out) {
                        var resultDelim = schema.resultDelimiter,
                            fieldDelim  = isString(schema.fieldDelimiter) &&
                                            schema.fieldDelimiter,
                            fields      = schema.resultFields || [],
                            results     = [],
                            parse       = Y.DataSchema.Base.parse,
                            results_in, fields_in, result, item,
                            field, key, value, i, j;
            
                        // Delete final delimiter at end of string if there
                        if (text_in.slice(-resultDelim.length) === resultDelim) {
                            text_in = text_in.slice(0, -resultDelim.length);
                        }
            
                        // Split into results
                        results_in = text_in.split(schema.resultDelimiter);
            
                        if (fieldDelim) {
                            for (i = results_in.length - 1; i >= 0; --i) {
                                result = {};
                                item = results_in[i];
            
                                fields_in = item.split(schema.fieldDelimiter);
            
                                for (j = fields.length - 1; j >= 0; --j) {
                                    field = fields[j];
                                    key = (!isUndef(field.key)) ? field.key : field;
                                    // FIXME: unless the key is an array index, this test
                                    // for fields_in[key] is useless.
                                    value = (!isUndef(fields_in[key])) ?
                                                fields_in[key] :
                                                fields_in[j];
            
                                    result[key] = parse.call(this, value, field);
                                }
            
                                results[i] = result;
                            }
                        } else {
                            results = results_in;
                        }
            
                        data_out.results = results;
            
                        return data_out;
                    }
                };
            
            Y.DataSchema.Text = Y.mix(SchemaText, Y.DataSchema.Base);