User Guide#

This guide provides a walkthrough of the major features in the hvpy package. hvpy is a python wrapper for the Helioviewer API, which is the same API that powers

Basic Usage#

Each API endpoint has a function in hvpy that shares the same name and has the same input parameters. For example if you are looking at getJP2Image in the Helioviewer documentation, you would execute this in hvpy with the following command:

import hvpy
from hvpy.datasource import DataSource
from datetime import datetime

jp2 = hvpy.getJP2Image(, DataSource.AIA_94.value)

Managing Return Types#

hvpy will attempt to coerce the result into a Python datatype for you. In general, there are 3 types of results you can expect from the API:

  1. Raw Data

  2. Strings

  3. JSON

In hvpy these return types map to:

  1. bytearray

  2. str

  3. dict

Sometimes the return type will change dependending on the input parameters you specify. Make sure to review your input parameters carefully. The descriptions in both our API Reference and the API Docs will say whether certain parameters change the output type.

Helper Functions#

hvpy provides a few helper functions for certain actions that generally require multiple API reqeusts. There are also helper functions for actions that may require more work than a simple API call.

Helper Flows#

For example, creating a movie requires calling hvpy.queueMovie followed by hvpy.getMovieStatus to see if the movie is done. Then you would call hvpy.downloadMovie to get the result. hvpy provides some helper functions to perform these flows for you.

Datasource & Event Selection#

Some API requests accept a list of datasources and events. These are in a very specific format. For example layering an SDO/AIA 94 and an SDO/AIA 304 image might look like “[13,1,50],[8,1,50]”. Since hvpy provides a one to one mapping, you would have to understand and create this string yourself. To do this, you would have to go figure out how helioviewer likes its layer strings, and find the IDs for each source.

hvpy makes this easy by providing a function for you. hvpy.utils.create_layers will create this string for you. You simply specify a tuple with the source enum you want, and the opacity it should have the end result.

from hvpy.utils import create_layers
from hvpy.datasource import DataSource

layer_string = create_layers([(DataSource.AIA_304, 50), (DataSource.AIA_94, 50)])

There is a similar function for choosing events that you want to have displayed in hvpy.utils.create_events

Miscellaneous Helpers#

hvpy also provides some miscellaneous helper functions. For example, since many API endpoints return raw data like images or videos, we’ve implemented a simple hvpy.utils.save_file to save this binary data to disk.