Add HttpClient

Issue-ID: AAF-996
Signed-off-by: Tomasz Wrobel <tomasz.wrobel@nokia.com>
Change-Id: I3ebb0ea88ef1a72c16064fd9a1931943b57410d8

1 files changed, 109 insertions, 0 deletions

diff --git a/certServiceClient/src/main/java/org/onap/aaf/certservice/client/httpclient/HttpClient.java b/certServiceClient/src/main/java/org/onap/aaf/certservice/client/httpclient/HttpClient.java
new file mode 100644
index 00000000..603d5848
--- /dev/null
+++ b/certServiceClient/src/main/java/org/onap/aaf/certservice/client/httpclient/HttpClient.java
@@ -0,0 +1,109 @@
+/*
+ * ============LICENSE_START=======================================================
+ * aaf-certservice-client
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.aaf.certservice.client.httpclient;
+
+import com.google.gson.Gson;
+import org.apache.http.HttpEntity;
+import org.apache.http.HttpResponse;
+import org.apache.http.HttpStatus;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.impl.client.CloseableHttpClient;
+import org.apache.http.util.EntityUtils;
+import org.onap.aaf.certservice.client.httpclient.exception.CertServiceApiResponseException;
+import org.onap.aaf.certservice.client.httpclient.exception.HttpClientException;
+import org.onap.aaf.certservice.client.httpclient.model.CertServiceResponse;
+import org.onap.aaf.certservice.client.httpclient.model.ErrorCertServiceResponse;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+
+public class HttpClient {
+
+    private static final String CSR_HEADER_NAME = "CSR";
+    private static final String PK_HEADER_NAME = "PK";
+    private static final String CHARSET_UTF_8 = "UTF-8";
+
+    private final Logger LOGGER = LoggerFactory.getLogger(HttpClient.class);
+
+    private final Gson gson = new Gson();
+    private final CloseableHttpClientProvider httpClientProvider;
+    private final String certServiceAddress;
+
+    public HttpClient(CloseableHttpClientProvider httpClientProvider, String certServiceAddress) {
+        this.httpClientProvider = httpClientProvider;
+        this.certServiceAddress = certServiceAddress;
+    }
+
+    public CertServiceResponse retrieveCertServiceData(String caName, String csr, String encodedPk)
+            throws CertServiceApiResponseException, HttpClientException {
+
+        try (CloseableHttpClient httpClient = httpClientProvider.getClient()) {
+            HttpResponse httpResponse = httpClient.execute(createHttpPayload(caName, csr, encodedPk));
+            return extractCertServiceResponse(httpResponse);
+
+        } catch (IOException e) {
+            LOGGER.error(String.format("Failed on communication between client and API for URL: '%s' . Exception message: '%s'",
+                    certServiceAddress + caName, e.getMessage()));
+            throw new HttpClientException(e);
+        }
+    }
+
+    private int getStatusCode(HttpResponse httpResponse) {
+        return httpResponse.getStatusLine().getStatusCode();
+    }
+
+    private CertServiceResponse extractCertServiceResponse(HttpResponse httpResponse)
+            throws CertServiceApiResponseException, IOException {
+        int httpResponseCode = getStatusCode(httpResponse);
+        if (HttpStatus.SC_OK != httpResponseCode) {
+            LOGGER.error(String.format("Error on API response. Response Code: %d", httpResponseCode));
+            throw generateApiResponseException(httpResponse);
+        }
+        String jsonResponse = getStringResponse(httpResponse.getEntity());
+        return gson.fromJson(jsonResponse, CertServiceResponse.class);
+    }
+
+    private String getStringResponse(HttpEntity httpEntity) throws IOException {
+        return EntityUtils.toString(httpEntity, CHARSET_UTF_8);
+    }
+
+    private HttpGet createHttpPayload(String caName, String csr, String pk) {
+        String url = certServiceAddress + caName;
+        HttpGet httpGet = new HttpGet(url);
+        httpGet.addHeader(CSR_HEADER_NAME, csr);
+        httpGet.addHeader(PK_HEADER_NAME, pk);
+        return httpGet;
+    }
+
+
+    private CertServiceApiResponseException generateApiResponseException(HttpResponse httpResponse) throws IOException {
+        String stringResponse = getStringResponse(httpResponse.getEntity());
+        ErrorCertServiceResponse errorCertServiceResponse =
+                gson.fromJson(stringResponse, ErrorCertServiceResponse.class);
+
+        String messageFromApi = errorCertServiceResponse.getMessage();
+        String path = errorCertServiceResponse.getPath();
+        int httpResponseCode = getStatusCode(httpResponse);
+
+        return new CertServiceApiResponseException(certServiceAddress + path, httpResponseCode, messageFromApi);
+    }
+}