backend.ckan.js | |
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this.recline = this.recline || {};
-this.recline.Backend = this.recline.Backend || {};
-this.recline.Backend.Ckan = this.recline.Backend.Ckan || {};
-
-(function($, my) { | |
CKAN Backend- -This provides connection to the CKAN DataStore (v2) - -General notes - -We need 2 things to make most requests: - -
There are 2 ways to specify this information. - -EITHER (checked in order): - -
OR: - -Set the url attribute of the dataset to point to the Resource on the CKAN instance. The endpoint and id will then be automatically computed. | my.__type__ = 'ckan'; |
| Default CKAN API endpoint used for requests (you can change this but it will affect every request!) - -DEPRECATION: this will be removed in v0.7. Please set endpoint attribute on dataset instead | my.API_ENDPOINT = 'http://datahub.io/api'; |
fetch | my.fetch = function(dataset) {
- if (dataset.endpoint) {
- var wrapper = my.DataStore(dataset.endpoint);
- } else {
- var out = my._parseCkanResourceUrl(dataset.url);
- dataset.id = out.resource_id;
- var wrapper = my.DataStore(out.endpoint);
- }
- var dfd = $.Deferred();
- var jqxhr = wrapper.search({resource_id: dataset.id, limit: 0});
- jqxhr.done(function(results) { |
| map ckan types to our usual types ... | var fields = _.map(results.result.fields, function(field) {
- field.type = field.type in CKAN_TYPES_MAP ? CKAN_TYPES_MAP[field.type] : field.type;
- return field;
- });
- var out = {
- fields: fields,
- useMemoryStore: false
- };
- dfd.resolve(out);
- });
- return dfd.promise();
- }; |
| only put in the module namespace so we can access for tests! | my._normalizeQuery = function(queryObj, dataset) {
- var actualQuery = {
- resource_id: dataset.id,
- q: queryObj.q,
- limit: queryObj.size || 10,
- offset: queryObj.from || 0
- };
- if (queryObj.sort && queryObj.sort.length > 0) {
- var _tmp = _.map(queryObj.sort, function(sortObj) {
- return sortObj.field + ' ' + (sortObj.order || '');
- });
- actualQuery.sort = _tmp.join(',');
- }
- return actualQuery;
- }
-
- my.query = function(queryObj, dataset) {
- if (dataset.endpoint) {
- var wrapper = my.DataStore(dataset.endpoint);
- } else {
- var out = my._parseCkanResourceUrl(dataset.url);
- dataset.id = out.resource_id;
- var wrapper = my.DataStore(out.endpoint);
- }
- var actualQuery = my._normalizeQuery(queryObj, dataset);
- var dfd = $.Deferred();
- var jqxhr = wrapper.search(actualQuery);
- jqxhr.done(function(results) {
- var out = {
- total: results.result.total,
- hits: results.result.records,
- };
- dfd.resolve(out);
- });
- return dfd.promise();
- }; |
DataStore- -Simple wrapper around the CKAN DataStore API - -@param endpoint: CKAN api endpoint (e.g. http://datahub.io/api) | my.DataStore = function(endpoint) {
- var that = {
- endpoint: endpoint || my.API_ENDPOINT
- };
- that.search = function(data) {
- var searchUrl = that.endpoint + '/3/action/datastore_search';
- var jqxhr = $.ajax({
- url: searchUrl,
- data: data,
- dataType: 'json'
- });
- return jqxhr;
- }
-
- return that;
- }; |
| Parse a normal CKAN resource URL and return API endpoint etc - -Normal URL is something like http://demo.ckan.org/dataset/some-dataset/resource/eb23e809-ccbb-4ad1-820a-19586fc4bebd | my._parseCkanResourceUrl = function(url) {
- parts = url.split('/');
- var len = parts.length;
- return {
- resource_id: parts[len-1],
- endpoint: parts.slice(0,[len-4]).join('/') + '/api'
- }
- };
-
- var CKAN_TYPES_MAP = {
- 'int4': 'integer',
- 'int8': 'integer',
- 'float8': 'float'
- };
-
-}(jQuery, this.recline.Backend.Ckan));
-
- |