solarnetwork / sn-datum-loader-js

Classes to load datum for time ranges.

SolarNetwork Datum Loader - JavaScript

This project contains classes to help with loading SolarNetwork datum over time ranges.

To include the library in your NPM-based project, run the following:

npm i solarnetwork-datum-loader

API docs

The latest API documentation is published here, or you can build the API documentation by running the apidoc script:

npm run apidoc

That will produce HTML documentation in docs/html.

DatumLoader

The DatumLoader class helps return data from the SolarQuery /datum/list endpoint. The class takes care of loading all results for a given search criteria, including making multiple API requests to download all result pages when more than one page of results are available.

Here's an example of loading a month's worth of data for SolarNode 123:

const filter = new DatumFilter();
filter.nodeId = 123;
filter.startDate = new Date("Sat, 1 Apr 2017 12:00:00 GMT");
filter.endDate = new Date("Mon, 1 May 2017 12:00:00 GMT");

const api = new SolarQueryApi();

new DatumLoader(api, filter).load((error, results) => {
	// results is an array of Datum objects
});

A Promise based API is available as well:

const result = await new DatumLoader(api, filter).fetch();

MultiLoader

The MultiLoader class helps load data from multiple Loader objects (the DatumLoader class conforms to that interface). This is useful for pulling down data from different search criterias all in one go. For example:

const filter1 = new DatumFilter();
filter1.nodeId = 123;
filter1.sourceId = "a";

const filter2 = new DatumFilter();
filter2.nodeId = 234;
filter2.sourceIds = ["b", "c"];

const api = new SolarQueryApi();

new MultiLoader([
	new DatumLoader(api, filter1),
	new DatumLoader(api, filter2),
]).load((error, results) => {
	// results is a 2-element array of Datum arrays
});

# or via promise...
const result = await new MultiLoader([
	new DatumLoader(api, filter1),
	new DatumLoader(api, filter2),
]).fetch();

DatumRangeFinder

The DatumRangeFinder class helps find the date range of available data for a set of SolarNodes. This is useful when generating reports or charts for a set of SolarNode datum streams, so the overall start/end dates can be determined before requesting the actual data. For example:

const api = new SolarQueryApi();

const filter = new DatumFilter();
filter.nodeId = 123;
filter.sourceIds = ["a", "b"];

const range = await new DatumRangeFinder(api, filter).fetch();

Ranges for more complex queries can be accomplished by passing in an array of filters, like this example, continuing from the last one:

const filter2 = new DatumFilter();
filter2.nodeId = 234;
filter2.sourceId = "c";

const range2 = await new DatumRangeFinder(api, [filter1, filter2]).fetch();

DatumSourceFinder

The DatumSourceFinder class helps find the available source IDs for a set of node IDs.

const api = new SolarQueryApi();

const filter = new DatumFilter();
filter.nodeId = 123;

const sources = await new DatumSourceFinder(api, filter).fetch();

Wildcard patterns can also be used to limit the search to a more specific set of source IDs, and start/end dates can also be used to narrow the search, for example:

const api = new SolarQueryApi();

const filter = new DatumFilter();
filter.startDate = new Date(Date.now() - 24 * 60 * 60 * 1000);
filter.sourceId = "/power/**";

const sources2 = await new DatumSourceFinder(api, filter).fetch();

Building

The build uses NPM and requires Node 18+. First, initialize the dependencies:

npm ci

Then you can run the build script:

npm run build:dist

That will produce ES2022 modules with an entry point in lib/index.js.

You can also produce an ES2022 bundle by running npm run build:bundle. That will produce a single bundled file at lib/solarnetwork-datum-loader.es.js.

Releases

Releases are done using the gitflow branching model. Gitflow must be installed on your host system. Then you can run

npm run release

to version, build, commit, and publish the release. See the generate-release site for more information.

Unit tests

The unit tests can be run by running the test script:

npm test

That will output the test results and produce a HTML code coverage report at coverage/index.html.