DataStore Plugin Development

Overview

By developing a DataStore plugin, you can add content retrieval functionality from new data sources to Fess.

Basic Structure

DataStore plugins extend AbstractDataStore.

Minimum Implementation

package org.codelibs.fess.ds.example;

import java.util.Map;

import org.codelibs.fess.ds.AbstractDataStore;
import org.codelibs.fess.ds.callback.IndexUpdateCallback;
import org.codelibs.fess.opensearch.config.exentity.DataConfig;

public class ExampleDataStore extends AbstractDataStore {

    @Override
    public String getName() {
        return "Example";
    }

    @Override
    protected void storeData(
            final DataConfig dataConfig,
            final IndexUpdateCallback callback,
            final Map<String, String> paramMap,
            final Map<String, String> scriptMap,
            final Map<String, Object> defaultDataMap) {

        // Implement data retrieval and processing here
    }
}

AbstractDataStore

Main Methods

Method Description
getName() Returns the DataStore name (required)
storeData() Performs data retrieval and index registration (required)
register() Registers the plugin

Parameters

Parameters passed to the storeData() method:

  • dataConfig: DataStore configuration

  • callback: Index update callback

  • paramMap: Parameters configured in admin console

  • scriptMap: Script configuration

  • defaultDataMap: Default data map

Implementation Examples

Simple DataStore

@Override
protected void storeData(
        final DataConfig dataConfig,
        final IndexUpdateCallback callback,
        final Map<String, String> paramMap,
        final Map<String, String> scriptMap,
        final Map<String, Object> defaultDataMap) {

    // Get parameters
    final String apiUrl = paramMap.get("api.url");
    final String apiKey = paramMap.get("api.key");

    try {
        // Fetch data
        List<Document> documents = fetchDocuments(apiUrl, apiKey);

        // Process each document
        for (Document doc : documents) {
            final Map<String, Object> dataMap = new HashMap<>(defaultDataMap);

            // Map data
            dataMap.put("url", doc.getUrl());
            dataMap.put("title", doc.getTitle());
            dataMap.put("content", doc.getContent());
            dataMap.put("lastModified", doc.getUpdatedAt());

            // Execute scripts (mapping)
            final Map<String, Object> resultMap = new HashMap<>();
            for (Map.Entry<String, String> entry : scriptMap.entrySet()) {
                Object value = convertValue(entry.getValue(), dataMap);
                if (value != null) {
                    resultMap.put(entry.getKey(), value);
                }
            }

            // Register to index
            callback.store(paramMap, resultMap);
        }
    } catch (Exception e) {
        logger.error("Failed to crawl data", e);
    }
}

Pagination Support

@Override
protected void storeData(...) {
    int page = 0;
    int pageSize = 100;

    while (true) {
        List<Document> documents = fetchDocuments(apiUrl, apiKey, page, pageSize);

        if (documents.isEmpty()) {
            break;
        }

        for (Document doc : documents) {
            processDocument(doc, callback, paramMap, scriptMap, defaultDataMap);
        }

        page++;
    }
}

Authentication Implementation

OAuth 2.0

protected String getAccessToken(String clientId, String clientSecret, String refreshToken) {
    // Token refresh
    OkHttpClient client = new OkHttpClient();

    RequestBody body = new FormBody.Builder()
        .add("grant_type", "refresh_token")
        .add("client_id", clientId)
        .add("client_secret", clientSecret)
        .add("refresh_token", refreshToken)
        .build();

    Request request = new Request.Builder()
        .url("https://oauth.example.com/token")
        .post(body)
        .build();

    try (Response response = client.newCall(request).execute()) {
        JsonNode json = objectMapper.readTree(response.body().string());
        return json.get("access_token").asText();
    }
}

API Key Authentication

protected Response callApi(String url, String apiKey) {
    Request request = new Request.Builder()
        .url(url)
        .addHeader("Authorization", "Bearer " + apiKey)
        .build();

    return httpClient.newCall(request).execute();
}

Error Handling

@Override
protected void storeData(...) {
    try {
        // Processing
    } catch (AuthenticationException e) {
        logger.error("Authentication failed. Check your credentials.", e);
        throw new DataStoreException("Authentication failed", e);
    } catch (RateLimitException e) {
        logger.warn("Rate limit exceeded. Waiting...");
        Thread.sleep(60000);
        // Retry logic
    } catch (Exception e) {
        logger.error("Unexpected error occurred", e);
        throw new DataStoreException("Failed to crawl data", e);
    }
}

Testing

Unit Testing

public class ExampleDataStoreTest {

    private ExampleDataStore dataStore;

    @Before
    public void setUp() {
        dataStore = new ExampleDataStore();
    }

    @Test
    public void testGetName() {
        assertEquals("Example", dataStore.getName());
    }

    @Test
    public void testFetchDocuments() {
        // Test using mocks
    }
}

Configuration Example

Example configuration in admin console:

Parameters

api.url=https://api.example.com/v1
api.key=your_api_key
max.items=1000
include.folders=folder1,folder2

Scripts

url=data.url
title=data.name
content=data.content
lastModified=data.updated_at
mimetype=data.content_type

Reference