summaryrefslogtreecommitdiffstats
path: root/dcae-analytics/dcae-analytics-model/src/main/java/org/onap/dcae/analytics/model/util/function/URLToHttpGetFunction.java
diff options
context:
space:
mode:
Diffstat (limited to 'dcae-analytics/dcae-analytics-model/src/main/java/org/onap/dcae/analytics/model/util/function/URLToHttpGetFunction.java')
-rw-r--r--dcae-analytics/dcae-analytics-model/src/main/java/org/onap/dcae/analytics/model/util/function/URLToHttpGetFunction.java77
1 files changed, 77 insertions, 0 deletions
diff --git a/dcae-analytics/dcae-analytics-model/src/main/java/org/onap/dcae/analytics/model/util/function/URLToHttpGetFunction.java b/dcae-analytics/dcae-analytics-model/src/main/java/org/onap/dcae/analytics/model/util/function/URLToHttpGetFunction.java
new file mode 100644
index 0000000..fe5ae07
--- /dev/null
+++ b/dcae-analytics/dcae-analytics-model/src/main/java/org/onap/dcae/analytics/model/util/function/URLToHttpGetFunction.java
@@ -0,0 +1,77 @@
+/*
+ * ================================================================================
+ * Copyright (c) 2018 AT&T Intellectual Property. 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.dcae.analytics.model.util.function;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.util.Optional;
+import java.util.Scanner;
+import java.util.function.Function;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Simple Function that calls http 'GET' on given URL and returns the response as String if successful. This function
+ * has side effects and only used for convenience in lambda expressions
+ * <p>
+ * NOTE: Suitable for only light weight http get requests as this will be a blocking call
+ *
+ * @author Rajiv Singla
+ */
+public class URLToHttpGetFunction implements Function<URL, Optional<String>> {
+
+ private static final Logger logger = LoggerFactory.getLogger(URLToHttpGetFunction.class);
+
+ @Override
+ public Optional<String> apply(final URL url) {
+
+ try {
+ final HttpURLConnection httpConnection = (HttpURLConnection) url.openConnection();
+ httpConnection.setRequestMethod("GET");
+
+ logger.info("Sending 'GET' request to URL : {}", url);
+ final int responseCode = httpConnection.getResponseCode();
+
+ if (responseCode == 200) {
+ final StringBuilder responseString = new StringBuilder();
+ try (Scanner scanner = new Scanner(httpConnection.getInputStream(), StandardCharsets.UTF_8.name())) {
+ while (scanner.hasNext()) {
+ responseString.append(scanner.next());
+ }
+ }
+
+ logger.info("Successful Response: {}", responseString);
+ return Optional.of(responseString.toString());
+ }
+
+ logger.error("Unsuccessful Response Code: {} when calling URL: {}", responseCode, url);
+
+ } catch (IOException e) {
+
+ logger.error("Unable to create HTTP URL Connection to URL:" + url, e);
+
+ }
+
+ return Optional.empty();
+ }
+}