Germanet-common

This is a Javascript library for building Web applications using the different types of data in GermaNet, namely

• synsets (see Synsets)
• conceptual relations (see ConRels)
• lexical units (see LexUnits)
• lexical relations (see LexRels)
• examples for lexical items (see LexExamples)
• compounds (see Compounds)
• frames (see Frames)
• Interlingual Index records (see ILIRecords)
• Wiktionary definitions (see WiktionaryDefs)

GermaNet Rover is an example of an application built with this library.

The library provides abstractions for implementing the following pattern with React and Redux:

1. Fetching data objects from a JSON API into the Redux store (see APIWrapper)
2. Selecting data objects from the store into a container component (see DataContainer)
3. Rendering the data in a container into a concrete UI (see GenericDisplay and GenericForms)

The library also implements steps 1 and 2 of this pattern for each of the GermaNet data types above. This enables applications using this library to focus on rendering GermaNet data for their own specific use cases, without having to write a lot of boilerplate for fetching that data and shuffling it around.

Note: if you are reading this README on NPM, the relative links on this page will be broken. You can read the complete source and documentation on GitHub, or by installing the package.

Code structure

The code is organized around the various functions in the general pattern described above. Each of these groupings consists of a React component, or a set of related components, together with any functions needed to manage their state via Redux. Every grouping thus consists of a directory under components with at least these files:

• README.md: documentation specific to the component(s)
• component.jsx: the definition of the component(s)

If the component has local state managed by Redux, the following files will also be present:

• actions.js: Redux actions for the component(s)
• reducers.js: Redux reducers for managing the component's state
• selectors.js: Redux selectors which map the Redux state to the component's props

In some cases (notably DataContainer and APIWrapper), the component is a higher-order component. In that case, the directory structure follows the same pattern, but the associated actions, reducers, and selectors are also higher order. For example, in APIWrapper's actions.js, instead of direct definitions of action creators, there is a makeQueryActions function that returns action creators.

In addition, there are several other files that contain code shared across the library:

• errors.js: assorted error classes and handling functions
• helpers.js: assorted common utility functions

Use

Installing the package

The library is available as a package on NPM in the @sfstuebingen scope. To install the package, run

npm install --save '@sfstuebingen/germanet-common'

in the directory containing your node_modules directory. (For internal projects at the SfS, this is probably webui.)

The library is shipped as ES2015 source code only. Consuming applications are expected to include whatever code they need from the library via their own build process.

When you use this library in another project, that project should also have the following NPM packages installed:

• axios
• react
• react-dom
• redux
• react-redux
• seamless-immutable

These are listed as peer dependencies in the package.json file. This means that this package depends on them, but installing the package will not install them automatically. Instead, you must manually ensure that they are installed. Consuming applications (for instance, any project based on the SfS' reactprojecttemplate repository) are likely to depend on these packages already, so you may already have them installed in your project. Listing them as peer dependencies helps prevent multiple versions from being installed, which causes problems with React in particular.

Installing reducers

To make the library useful, you will need to install several reducers from this library into your root Redux reducer. You can import them from the top-level reducers.js:

import { synsetSearches, dataContainers, apiData } from '@sfstuebingen/germanet-common/reducers';
import { combineReducers } from 'redux';

const rootReducer = combineReducers({
   ...
   synsetSearches,
   dataContainers,
   apiData,
   ...
});

In addition to handling their specified actions, these top-level reducers respond to the global actions for the library (defined in the top-level actions.js). They will, for example, clear all the state that they manage when a RESET_GERMANET_COMMON action is emitted. The reducers defined in individual component directories do not respond to these global actions, so you should not import them directly unless you want to override how these global actions are handled.

Importing and using the components and other code

In general, you should just import the object you want using the full path within this package to the file where it is defined:

import { lexUnitQueries } from '@sfstuebingen/germanet-common/components/LexUnits/actions';

As a shortcut, you can import any React component from the library just using the path to the directory containing its definition (leaving 'component' off at the end):

import { LexUnitsContainer, LexUnitsAsList } from '@sfstuebingen/germanet-common/components/LexUnits';

All components are also re-exported from @sfstuebingen/germanet-common/components, so you can also leave off the name of the component's directory:

import { LexUnitsContainer, LexUnitsAsList } from '@sfstuebingen/germanet-common/components';

API path

By default, the library expects to make API calls to endpoints that fall under /api, e.g., /api/synsets. You can customize this by setting either window.GERMANET_API_PREFIX (recommended for new or external projects) or window.APP_CONTEXT_PATH (for existing applications at the SfS) to a prefix for these endpoints. Note that you should do this before loading the library's code. For example, if you set window.GERMANET_API_PREFIX = '/germanet'; then API requests will go to endpoints like /germanet/api/synsets. If you need more control over the exact path, you should edit the urlRoot variable in the top-level constants.js module.

Using a custom axios instance

The library uses axios to make API requests. If you need to provide a custom instance of axios, you can do so with the installAxiosInstance function in constants.js:

import { installAxiosInstance } from '@sfstuebingen/germanet-common/constants';
import axios from 'axios';

const myAxiosInstance = axios.create();

// tell germanet-common to make API requests with your custom axios instance:
installAxiosInstance(myAxiosInstance);

This is useful if, for example, you need to catch and respond to HTTP errors that result from API requests, which you can do with axios' interceptors.