Amazon and eBay Buy/Sell APIs

src/main/java/de/rwu/easydrop/api/client/AbstractDataSource.java

@@ -42,7 +42,7 @@ public abstract class AbstractDataSource implements DataSource {
     protected abstract ProductDTO buildProductDTO(ProductDTO product, String json);
 
     /**
-     * Overridable standard implementation.
+     * Pulls product data from a remote data source.
      */
     @Override
     public ProductDTO getProductDTOById(final String productIdentifier)

src/main/java/de/rwu/easydrop/api/client/AbstractDataWriter.java

@@ -0,0 +1,81 @@
+package de.rwu.easydrop.api.client;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.MalformedURLException;
+import java.net.URL;
+
+import de.rwu.easydrop.api.dto.ProductDTO;
+import de.rwu.easydrop.exception.DataWriterException;
+import de.rwu.easydrop.util.FormattingUtil;
+
+/**
+ * Writes data to a remote API.
+ *
+ * @since 0.3.0
+ */
+public abstract class AbstractDataWriter {
+
+    /**
+     * Returns the data source's API key.
+     *
+     * @return Data source API key
+     */
+    protected abstract String getApiKey();
+
+    /**
+     * Returns the target API's name.
+     *
+     * @return Data target API name
+     */
+    protected abstract String getDataTarget();
+
+    /**
+     * Creates an URL object to connect to the API with.
+     *
+     * @param productIdentifier Product identifier
+     * @return URL object
+     * @throws MalformedURLException
+     */
+    protected abstract URL createApiUrl(String productIdentifier) throws MalformedURLException;
+
+    /**
+     * Sends a put request to the API.
+     *
+     * @param dto     Product data transfer object
+     * @param apiType API Type, like Purchase or Sales
+     */
+    protected void sendPutRequest(final ProductDTO dto, final String apiType) {
+        String apiKey = getApiKey();
+        String dataTarget = getDataTarget();
+
+        if (!dataTarget.equals(dto.getDataOrigin())) {
+            throw new DataWriterException(
+                    "Product data source and target " + apiType + " API are incompatible.");
+        }
+
+        try {
+            String urlReadyIdentifier = FormattingUtil.urlEncode(dto.getProductId());
+            URL apiUrl = createApiUrl(urlReadyIdentifier);
+
+            HttpURLConnection connection = (HttpURLConnection) apiUrl.openConnection();
+            connection.setRequestMethod("PUT");
+            connection.setRequestProperty("Credential", apiKey);
+
+            int responseCode = connection.getResponseCode();
+            if (responseCode != HttpURLConnection.HTTP_OK) {
+                throw new DataWriterException(
+                        dataTarget
+                                + " "
+                                + apiType
+                                + " API responded with error code "
+                                + responseCode);
+            }
+        } catch (IOException e) {
+            throw new DataWriterException(
+                    "Couldn't fulfill "
+                            + dataTarget
+                            + " API request");
+        }
+    }
+}

src/main/java/de/rwu/easydrop/api/client/AbstractPurchaser.java

@@ -0,0 +1,19 @@
+package de.rwu.easydrop.api.client;
+
+import de.rwu.easydrop.api.dto.ProductDTO;
+
+/**
+ * Abstract construct to provide access to a purchase API.
+ *
+ * @since 0.3.0
+ */
+public abstract class AbstractPurchaser extends AbstractDataWriter {
+    /**
+     * Sends a buy request to the Amazon API.
+     *
+     * @param dto
+     */
+    public void purchaseProduct(final ProductDTO dto) {
+        sendPutRequest(dto, "Purchase");
+    }
+}

src/main/java/de/rwu/easydrop/api/client/AbstractSeller.java

@@ -0,0 +1,19 @@
+package de.rwu.easydrop.api.client;
+
+import de.rwu.easydrop.api.dto.ProductDTO;
+
+/**
+ * Abstract construct to provide access to a sales API.
+ *
+ * @since 0.3.0
+ */
+public abstract class AbstractSeller extends AbstractDataWriter {
+    /**
+     * Sends a sell request to the Amazon API.
+     *
+     * @param dto
+     */
+    public void sellProduct(final ProductDTO dto) {
+        sendPutRequest(dto, "Sales");
+    }
+}

src/main/java/de/rwu/easydrop/api/client/AmazonPurchaser.java

@@ -0,0 +1,67 @@
+package de.rwu.easydrop.api.client;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+
+/**
+ * Sends a buy request to the Amazon API.
+ *
+ * @since 0.3.0
+ */
+public final class AmazonPurchaser extends AbstractPurchaser {
+    /**
+     * Name of this data source.
+     */
+    private static final String DATA_TARGET = "Amazon";
+    /**
+     * Base URL to the Amazon Purchase API.
+     */
+    private String baseUrl;
+    /**
+     * Access credential.
+     */
+    private String apiKey;
+    /**
+     * Product region parameter required for data writes.
+     */
+    private static final String PRODUCT_REGION = "DE";
+    /**
+     * Locale parameter required for data writes.
+     */
+    private static final String LOCALE = "de_DE";
+
+    /**
+     * Sets up instance with Base URL and API Key.
+     *
+     * @param newBaseUrl
+     * @param newApiKey
+     */
+    public AmazonPurchaser(final String newBaseUrl, final String newApiKey) {
+        this.baseUrl = newBaseUrl;
+        this.apiKey = newApiKey;
+    }
+
+    /**
+     * @param productId ASIN
+     */
+    @Override
+    protected URL createApiUrl(final String productId) throws MalformedURLException {
+        return new URL(baseUrl
+                + "/products/2020-08-26/products/"
+                + productId
+                + "/buy?productRegion="
+                + PRODUCT_REGION
+                + "&locale="
+                + LOCALE);
+    }
+
+    @Override
+    protected String getApiKey() {
+        return this.apiKey;
+    }
+
+    @Override
+    protected String getDataTarget() {
+        return DATA_TARGET;
+    }
+}

src/main/java/de/rwu/easydrop/api/client/AmazonSeller.java

@@ -0,0 +1,67 @@
+package de.rwu.easydrop.api.client;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+
+/**
+ * Sends a sell request to the Amazon API.
+ *
+ * @since 0.3.0
+ */
+public final class AmazonSeller extends AbstractSeller {
+    /**
+     * Name of this data source.
+     */
+    private static final String DATA_TARGET = "Amazon";
+    /**
+     * Base URL to the Amazon Purchase API.
+     */
+    private String baseUrl;
+    /**
+     * Access credential.
+     */
+    private String apiKey;
+    /**
+     * Product region parameter required for data writes.
+     */
+    private static final String PRODUCT_REGION = "DE";
+    /**
+     * Locale parameter required for data writes.
+     */
+    private static final String LOCALE = "de_DE";
+
+    /**
+     * Sets up instance with Base URL and API Key.
+     *
+     * @param newBaseUrl
+     * @param newApiKey
+     */
+    public AmazonSeller(final String newBaseUrl, final String newApiKey) {
+        this.baseUrl = newBaseUrl;
+        this.apiKey = newApiKey;
+    }
+
+    /**
+     * @param productId ASIN
+     */
+    @Override
+    protected URL createApiUrl(final String productId) throws MalformedURLException {
+        return new URL(baseUrl
+                + "/products/2020-08-26/products/"
+                + productId
+                + "/sell?productRegion="
+                + PRODUCT_REGION
+                + "&locale="
+                + LOCALE);
+    }
+
+    @Override
+    protected String getApiKey() {
+        return apiKey;
+    }
+
+    @Override
+    protected String getDataTarget() {
+        return DATA_TARGET;
+    }
+}

src/main/java/de/rwu/easydrop/api/client/EbayPurchaser.java

@@ -0,0 +1,52 @@
+package de.rwu.easydrop.api.client;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+
+/**
+ * Sends a buy request to the eBay API.
+ *
+ * @since 0.3.0
+ */
+public final class EbayPurchaser extends AbstractPurchaser {
+    /**
+     * Name of this data source.
+     */
+    private static final String DATA_TARGET = "eBay";
+    /**
+     * Base URL to the eBay Purchase API.
+     */
+    private String baseUrl;
+    /**
+     * Access credential.
+     */
+    private String apiKey;
+
+    /**
+     * Sets up instance with Base URL and API Key.
+     *
+     * @param newBaseUrl
+     * @param newApiKey
+     */
+    public EbayPurchaser(final String newBaseUrl, final String newApiKey) {
+        this.baseUrl = newBaseUrl;
+        this.apiKey = newApiKey;
+    }
+
+    @Override
+    protected URL createApiUrl(final String searchQuery) throws MalformedURLException {
+        return new URL(baseUrl
+                + "/buy/"
+                + searchQuery);
+    }
+
+    @Override
+    protected String getApiKey() {
+        return apiKey;
+    }
+
+    @Override
+    protected String getDataTarget() {
+        return DATA_TARGET;
+    }
+}

src/main/java/de/rwu/easydrop/api/client/EbaySeller.java

@@ -0,0 +1,52 @@
+package de.rwu.easydrop.api.client;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+
+/**
+ * Sends a sell request to the eBay API.
+ *
+ * @since 0.3.0
+ */
+public final class EbaySeller extends AbstractSeller {
+    /**
+     * Name of this data source.
+     */
+    private static final String DATA_TARGET = "eBay";
+    /**
+     * Base URL to the eBay Purchase API.
+     */
+    private String baseUrl;
+    /**
+     * Access credential.
+     */
+    private String apiKey;
+
+    /**
+     * Sets up instance with Base URL and API Key.
+     *
+     * @param newBaseUrl
+     * @param newApiKey
+     */
+    public EbaySeller(final String newBaseUrl, final String newApiKey) {
+        this.baseUrl = newBaseUrl;
+        this.apiKey = newApiKey;
+    }
+
+    @Override
+    protected URL createApiUrl(final String searchQuery) throws MalformedURLException {
+        return new URL(baseUrl
+                + "/sell/"
+                + searchQuery);
+    }
+
+    @Override
+    protected String getApiKey() {
+        return this.apiKey;
+    }
+
+    @Override
+    protected String getDataTarget() {
+        return DATA_TARGET;
+    }
+}

src/main/java/de/rwu/easydrop/exception/DataWriterException.java

@@ -0,0 +1,27 @@
+package de.rwu.easydrop.exception;
+
+/**
+ * Exception that signifies a communication problem with a writer API.
+ *
+ * @since 0.3.0
+ */
+public class DataWriterException extends RuntimeException {
+    /**
+     * Throws an exception that signifies the data of a Product are invalid.
+     *
+     * @param message
+     */
+    public DataWriterException(final String message) {
+        super(message);
+    }
+
+    /**
+     * Throws an exception that signifies the data of a Product are invalid.
+     *
+     * @param message
+     * @param cause
+     */
+    public DataWriterException(final String message, final Throwable cause) {
+        super(message, cause);
+    }
+}