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#297 Move API Gateway code into a new submodule: api-gateway-service. Change api-gateway packaging type to "pom". Update price-microservice and image-microservice to be true submodules of api-gateway

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tmcconville
2016-05-03 17:17:36 -05:00
parent a6036e5787
commit 8653eb87bc
14 changed files with 106 additions and 65 deletions
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64
api-gateway/api-gateway-service/src/main/java/com/iluwatar/api/gateway/ApiGateway.java Normal file
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/**
* The MIT License
* Copyright (c) 2014 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.api.gateway;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import javax.annotation.Resource;
/**
* The ApiGateway aggregates calls to microservices based on the needs of the individual clients.
*/
@RestController
public class ApiGateway {
@Resource
private ImageClient imageClient;
@Resource
private PriceClient priceClient;
/**
* Retrieves product information that desktop clients need
* @return Product information for clients on a desktop
*/
@RequestMapping("/desktop")
public DesktopProduct getProductDesktop() {
DesktopProduct desktopProduct = new DesktopProduct();
desktopProduct.setImagePath(imageClient.getImagePath());
desktopProduct.setPrice(priceClient.getPrice());
return desktopProduct;
}
/**
* Retrieves product information that mobile clients need
* @return Product information for clients on a mobile device
*/
@RequestMapping("/mobile")
public MobileProduct getProductMobile() {
MobileProduct mobileProduct = new MobileProduct();
mobileProduct.setPrice(priceClient.getPrice());
return mobileProduct;
}
}

66
api-gateway/api-gateway-service/src/main/java/com/iluwatar/api/gateway/App.java Normal file
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/**
* The MIT License
* Copyright (c) 2014 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.api.gateway;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
/**
* With the Microservices pattern, a client may need data from multiple different microservices.
* If the client called each microservice directly, that could contribute to longer load times,
* since the client would have to make a network request for each microservice called. Moreover,
* having the client call each microservice directly ties the client to that microservice - if the
* internal implementations of the microservices change (for example, if two microservices are
* combined sometime in the future) or if the location (host and port) of a microservice changes,
* then every client that makes use of those microservices must be updated.
*
* <p>
* The intent of the API Gateway pattern is to alleviate some of these issues. In the API Gateway
* pattern, an additional entity (the API Gateway) is placed between the client and the
* microservices. The job of the API Gateway is to aggregate the calls to the microservices.
* Rather than the client calling each microservice individually, the client calls the API Gateway
* a single time. The API Gateway then calls each of the microservices that the client needs.
*
* <p>
* This implementation shows what the API Gateway pattern could look like for an e-commerce site.
* The {@link ApiGateway} makes calls to the Image and Price microservices using the
* {@link ImageClientImpl} and {@link PriceClientImpl} respectively. Customers viewing the site on a
* desktop device can see both price information and an image of a product, so the {@link ApiGateway}
* calls both of the microservices and aggregates the data in the {@link DesktopProduct} model.
* However, mobile users only see price information; they do not see a product image. For mobile
* users, the {@link ApiGateway} only retrieves price information, which it uses to populate the
* {@link MobileProduct}.
*/
@SpringBootApplication
public class App {
/**
* Program entry point
*
* @param args
* command line args
*/
public static void main(String[] args) {
SpringApplication.run(App.class, args);
}
}

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api-gateway/api-gateway-service/src/main/java/com/iluwatar/api/gateway/DesktopProduct.java Normal file
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/**
* The MIT License
* Copyright (c) 2014 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.api.gateway;
/**
* Encapsulates all of the information that a desktop client needs to display a product.
*/
public class DesktopProduct {
/**
* The price of the product
*/
private String price;
/**
* The path to the image of the product
*/
private String imagePath;
public String getPrice() {
return price;
}
public void setPrice(String price) {
this.price = price;
}
public String getImagePath() {
return imagePath;
}
public void setImagePath(String imagePath) {
this.imagePath = imagePath;
}
}

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api-gateway/api-gateway-service/src/main/java/com/iluwatar/api/gateway/ImageClient.java Normal file
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/**
* The MIT License
* Copyright (c) 2014 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.api.gateway;
/**
* An interface used to communicate with the Image microservice
*/
public interface ImageClient {
String getImagePath();
}

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api-gateway/api-gateway-service/src/main/java/com/iluwatar/api/gateway/ImageClientImpl.java Normal file
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/**
* The MIT License
* Copyright (c) 2014 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.api.gateway;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.springframework.stereotype.Component;
import java.io.IOException;
/**
* An adapter to communicate with the Image microservice
*/
@Component
public class ImageClientImpl implements ImageClient{
/**
* Makes a simple HTTP Get request to the Image microservice
* @return The path to the image
*/
@Override
public String getImagePath() {
String response = null;
try (CloseableHttpClient httpClient = HttpClients.createDefault()) {
HttpGet httpGet = new HttpGet("http://localhost:50005/image-path");
try (CloseableHttpResponse httpResponse = httpClient.execute(httpGet)) {
response = EntityUtils.toString(httpResponse.getEntity());
}
} catch (IOException e) {
e.printStackTrace();
}
return response;
}
}

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api-gateway/api-gateway-service/src/main/java/com/iluwatar/api/gateway/MobileProduct.java Normal file
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/**
* The MIT License
* Copyright (c) 2014 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.api.gateway;
/**
* Encapsulates all of the information that mobile client needs to display a product.
*/
public class MobileProduct {
/**
* The price of the product
*/
private String price;
public String getPrice() {
return price;
}
public void setPrice(String price) {
this.price = price;
}
}

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api-gateway/api-gateway-service/src/main/java/com/iluwatar/api/gateway/PriceClient.java Normal file
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/**
* The MIT License
* Copyright (c) 2014 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.api.gateway;
/**
* An interface used to communicate with the Price microservice
*/
public interface PriceClient {
String getPrice();
}

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api-gateway/api-gateway-service/src/main/java/com/iluwatar/api/gateway/PriceClientImpl.java Normal file
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/**
* The MIT License
* Copyright (c) 2014 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.api.gateway;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.springframework.stereotype.Component;
import java.io.IOException;
/**
* An adapter to communicate with the Price microservice
*/
@Component
public class PriceClientImpl implements PriceClient{
/**
* Makes a simple HTTP Get request to the Price microservice
* @return The price of the product
*/
@Override
public String getPrice() {
String response = null;
try (CloseableHttpClient httpClient = HttpClients.createDefault()) {
HttpGet httpGet = new HttpGet("http://localhost:50006/price");
try (CloseableHttpResponse httpResponse = httpClient.execute(httpGet)) {
response = EntityUtils.toString(httpResponse.getEntity());
}
} catch (IOException e) {
e.printStackTrace();
}
return response;
}
}

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api-gateway/api-gateway-service/src/main/resources/application.properties Normal file
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#
# The MIT License
# Copyright (c) 2014 Ilkka Seppälä
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
#
server.port=50004

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api-gateway/api-gateway-service/src/test/java/com/iluwatar/api/gateway/ApiGatewayTest.java Normal file
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/**
* The MIT License
* Copyright (c) 2014 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.api.gateway;
import org.junit.Before;
import org.junit.Test;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;
import static org.junit.Assert.assertEquals;
import static org.mockito.Mockito.when;
public class ApiGatewayTest {
@InjectMocks
private ApiGateway apiGateway;
@Mock
private ImageClient imageClient;
@Mock
private PriceClient priceClient;
@Before
public void setup() {
MockitoAnnotations.initMocks(this);
}
/**
* Tests getting the data for a desktop client
*/
@Test
public void testGetProductDesktop() {
String imagePath = "/product-image.png";
String price = "20";
when(imageClient.getImagePath()).thenReturn(imagePath);
when(priceClient.getPrice()).thenReturn(price);
DesktopProduct desktopProduct = apiGateway.getProductDesktop();
assertEquals(price, desktopProduct.getPrice());
assertEquals(imagePath, desktopProduct.getImagePath());
}
/**
* Tests getting the data for a mobile client
*/
@Test
public void testGetProductMobile() {
String price = "20";
when(priceClient.getPrice()).thenReturn(price);
MobileProduct mobileProduct = apiGateway.getProductMobile();
assertEquals(price, mobileProduct.getPrice());
}
}