api custom header

Issue-ID: DCAEGEN2-897

Change-Id: Iaff1a8f71a0ab1be997fbea654d6032eee91009b
Signed-off-by: luna <nil@vmware.com>

4 files changed, 469 insertions, 0 deletions

diff --git a/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/header/ApiVersionManagement.java b/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/header/ApiVersionManagement.java
new file mode 100644
index 00000000..06515dca
--- /dev/null
+++ b/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/header/ApiVersionManagement.java
@@ -0,0 +1,141 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * org.onap.dcaegen2.services.sdk
+ * ================================================================================
+ * Copyright (C) 2019 vmware. 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.dcaegen2.services.sdk.standardization.header;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import org.onap.dcaegen2.services.sdk.standardization.util.ObjectManagement;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import com.google.gson.Gson;
+
+public final class ApiVersionManagement {
+
+  private static final Logger LOGGER = LoggerFactory.getLogger(ApiVersionManagement.class);
+  private static final Object INSTANCE = new Object();
+  private static final String API_VERSION = "apiVersion";
+
+  private static Map<String, List<ApiVersionModel>> verModelMap;
+
+  /**
+   * private constructor
+   */
+  private ApiVersionManagement() {
+
+  }
+
+  /**
+   * get api version from json string
+   * 
+   * @param apiFilePath api file path
+   * @param requestedApiName current api name
+   * @return all api version for a major version
+   */
+  public static List<ApiVersionModel> getApiVersion(String apiFilePath, String requestedApiName) {
+    if (null != verModelMap) {
+      List<ApiVersionModel> apiLst = verModelMap.get(requestedApiName);
+      return ObjectManagement.isCollectionEmpty(apiLst) ? Collections.emptyList()
+          : Collections.unmodifiableList(apiLst);
+    }
+
+    synchronized (INSTANCE) {
+      if (null == verModelMap) {
+        verModelMap = new HashMap<>();
+        String apiVerJsonStr = readApiVersions(apiFilePath);
+
+        // component not pass the apiversion parameter
+        if (apiVerJsonStr.isEmpty()) {
+          return Collections.emptyList();
+        }
+
+        // read service or resource api and put in HashMap one by one.
+        convertVerToModel(parseApiVersion(apiVerJsonStr));
+      }
+    }
+
+    List<ApiVersionModel> apiLst = verModelMap.get(requestedApiName);
+    return ObjectManagement.isCollectionEmpty(apiLst) ? Collections.emptyList()
+        : Collections.unmodifiableList(verModelMap.get(requestedApiName));
+  }
+
+  /**
+   * parse api versions from api json string
+   * 
+   * @param apiVerJsonStr all api versions in json format
+   * @return api versions<apikey, List<version>> in map format
+   */
+  private static Map<String, Object> parseApiVersion(String apiVerJsonStr) {
+    Map<String, Object> apiMap = new Gson().fromJson(apiVerJsonStr, Map.class);
+    if (apiMap.containsKey(API_VERSION)) {
+      return apiMap;
+    }
+
+    // there is no apiVersion filed in apiVerJsonStr or the format is wrong.
+    LOGGER.error("the struct of api version is wrong, so return the empty api map.");
+    return Collections.emptyMap();
+  }
+
+  /**
+   * convert api version into ApiVersionModel object
+   * 
+   * @param apiMap Map object for all api versions
+   */
+  private static void convertVerToModel(Map<String, Object> apiMap) {
+    if (apiMap.isEmpty()) {
+      verModelMap = Collections.emptyMap();
+      return;
+    }
+
+    List<Object> currApiArray = null;
+    Map<String, Object> apiVersMap = (apiMap.get(API_VERSION) instanceof Map) ? (Map) apiMap.get(API_VERSION) : null;
+    if (null != apiVersMap) {
+      for (Map.Entry<String, Object> entry : apiVersMap.entrySet()) {
+        currApiArray = (entry.getValue() instanceof List) ? (List) entry.getValue() : null;
+        if (null != currApiArray) {
+          List<ApiVersionModel> currApiLst = new ArrayList<>();
+          currApiArray.forEach(currApi -> currApiLst.add(new ApiVersionModel(currApi.toString())));
+          verModelMap.put(entry.getKey(), currApiLst);
+        }
+      }
+    }
+  }
+
+  /**
+   * read api version from path
+   * 
+   * @param filePath api versions
+   * @return api versions json string
+   */
+  private static String readApiVersions(String filePath) {
+    try {
+      return new String(Files.readAllBytes(Paths.get(filePath)));
+    } catch (IOException e) {
+      LOGGER.error("Fail to read api version file", e);
+    }
+
+    return "";
+  }
+}
\ No newline at end of file
diff --git a/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/header/ApiVersionModel.java b/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/header/ApiVersionModel.java
new file mode 100644
index 00000000..d3c09a2b
--- /dev/null
+++ b/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/header/ApiVersionModel.java
@@ -0,0 +1,53 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * org.onap.dcaegen2.services.sdk
+ * ================================================================================
+ * Copyright (C) 2019 vmware. 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.dcaegen2.services.sdk.standardization.header;
+
+public class ApiVersionModel {
+  private String majorVersion;
+  private String minorVersion;
+  private String patchVersion;
+  private String version;
+
+  public ApiVersionModel(String version) {
+    this.version = version;
+    if (null != version) {
+      String[] verArray = version.split("\\.");
+      majorVersion = verArray[0];
+      minorVersion = verArray.length > 1 ? verArray[1] : null;
+      patchVersion = verArray.length > 2 ? verArray[2] : null;
+    }
+  }
+
+  public String getMajorVersion() {
+    return majorVersion;
+  }
+
+  public String getMinorVersion() {
+    return minorVersion;
+  }
+
+  public String getPatchVersion() {
+    return patchVersion;
+  }
+
+  public String getVersion() {
+    return version;
+  }
+}
\ No newline at end of file
diff --git a/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/header/CustomHeaderUtils.java b/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/header/CustomHeaderUtils.java
new file mode 100644
index 00000000..ecd08314
--- /dev/null
+++ b/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/header/CustomHeaderUtils.java
@@ -0,0 +1,222 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * org.onap.dcaegen2.services.sdk
+ * ================================================================================
+ * Copyright (C) 2019 vmware. 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.dcaegen2.services.sdk.standardization.header;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import org.jetbrains.annotations.NotNull;
+import org.onap.dcaegen2.services.sdk.standardization.util.ObjectManagement;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class CustomHeaderUtils {
+
+  private static final Logger logger = LoggerFactory.getLogger(CustomHeaderUtils.class);
+
+  /**
+   * more detail:
+   * https://wiki.onap.org/display/DW/ONAP+API+Common+Versioning+Strategy+%28CVS%29+Guidelines
+   */
+  private static final String API_MINOR_VERSION = "X-MinorVersion";
+  private static final String API_PATCH_VERSION = "X-PatchVersion";
+  private static final String API_LATEST_VERSION = "X-LatestVersion";
+
+  /**
+   * identify whether validate minor version successfully
+   */
+  private static final ThreadLocal<Boolean> CLIENT_MINOR_VERSION_OK = new ThreadLocal<>();
+  private String majorVersion = null;
+  private String minorVersion = null;
+  private List<ApiVersionModel> verLst = null;
+
+  /**
+   * construct
+   * 
+   * @param requestMajorVer client request major version
+   * @param reqHeaderMap request headers
+   * @param apiFilePath api file path
+   * @param requestedApiName api name that is requested by client
+   * 
+   */
+  public CustomHeaderUtils(@NotNull String requestMajorVer, @NotNull Map<String, String> reqHeaderMap,
+      @NotNull String apiFilePath, @NotNull String requestedApiName) {
+    // all api versions
+    if (!requestedApiName.isEmpty()) {
+      verLst = ApiVersionManagement.getApiVersion(apiFilePath, requestedApiName);
+    }
+
+    // major version that client requests
+    this.majorVersion = requestMajorVer;
+
+    // minor version that client requests
+    this.minorVersion = reqHeaderMap.get(API_MINOR_VERSION);
+
+    CLIENT_MINOR_VERSION_OK.set(Boolean.TRUE);
+  }
+
+  /**
+   * get the custom headers of response
+   * 
+   * @return rspHeader custom headers of response
+   */
+  public Map<String, String> getRspCustomHeader() {
+    try {
+      return calCustomHeader();
+    } finally {
+      CLIENT_MINOR_VERSION_OK.remove();
+    }
+  }
+
+  /**
+   * calculate the custom header for response
+   * 
+   * @return rspHeader custom headers of response
+   */
+  private Map<String, String> calCustomHeader() {
+    if (ObjectManagement.isCollectionEmpty(this.verLst)) {
+      logger.warn("there is no api version configured in server.");
+      return new HashMap<>();
+    }
+
+    // if client not send X-MinorVersion, return the first minor version that major version is requested
+    if (ObjectManagement.isStringEmpty(this.minorVersion)) {
+      return calHeadersNoMinorVer();
+    }
+
+    // if client send x-MinorVersion, minor vefrsion is wrong
+    if (!CLIENT_MINOR_VERSION_OK.get()) {
+      return calHeadersWithWrongMinorVer();
+    }
+
+    // client send X-MinorVersion and minor version is right
+    return calHeadersWithMinorVer();
+  }
+
+  /**
+   * calculate the custom header should be returned when client send minor version which is wrong
+   * 
+   * @return rspHeader custom headers of response
+   */
+  private Map<String, String> calHeadersWithWrongMinorVer() {
+    Map<String, String> rspHeader = new HashMap<>(3);
+
+    // Latest version mean greatest version
+    rspHeader.put(API_LATEST_VERSION, this.verLst.get(verLst.size() - 1).getVersion());
+
+    ApiVersionModel currVer = null;
+    for (int index = 0; index < this.verLst.size(); index++) {
+      if (this.majorVersion.equals(this.verLst.get(index).getMajorVersion())) {
+        currVer = this.verLst.get(index);
+      } else {
+        if (null != currVer) {
+          break;
+        }
+      }
+    }
+
+    if (null == currVer) {
+      logger.warn("wrong apiVersiona are provided, major {} not foud in them", this.majorVersion);
+    } else {
+      rspHeader.put(API_MINOR_VERSION, currVer.getMinorVersion());
+      rspHeader.put(API_PATCH_VERSION, currVer.getPatchVersion());
+    }
+
+    return rspHeader;
+  }
+
+  /**
+   * calculate the custom header should be returned when client send minor version which is right
+   * 
+   * @return rspHeader custom headers of response
+   */
+  private Map<String, String> calHeadersWithMinorVer() {
+    Map<String, String> rspHeader = new HashMap<>(3);
+
+    // Latest version mean greatest version
+    rspHeader.put(API_LATEST_VERSION, this.verLst.get(verLst.size() - 1).getVersion());
+
+    // set minor version
+    rspHeader.put(API_MINOR_VERSION, this.minorVersion);
+
+    // set patch version
+    ApiVersionModel currVer = null;
+    for (int index = 0; index < this.verLst.size(); index++) {
+      currVer = verLst.get(index);
+      if (this.majorVersion.equals(currVer.getMajorVersion()) && this.minorVersion.equals(currVer.getMinorVersion())) {
+        rspHeader.put(API_PATCH_VERSION, currVer.getPatchVersion());
+        break;
+      }
+    }
+
+    return rspHeader;
+  }
+
+  /**
+   * calculate the custom header should be returned when client not send minor version
+   * 
+   * @return rspHeader custom headers of response
+   */
+  private Map<String, String> calHeadersNoMinorVer() {
+    Map<String, String> rspHeader = new HashMap<>(3);
+
+    // Latest version mean greatest version
+    rspHeader.put(API_LATEST_VERSION, this.verLst.get(verLst.size() - 1).getVersion());
+
+    // the first version of major version
+    ApiVersionModel currVer = null;
+    for (int index = 0; index < this.verLst.size(); index++) {
+      currVer = verLst.get(index);
+      if (this.majorVersion.equals(currVer.getMajorVersion())) {
+        rspHeader.put(API_MINOR_VERSION, currVer.getMinorVersion());
+        rspHeader.put(API_PATCH_VERSION, currVer.getPatchVersion());
+        break;
+      }
+    }
+
+    return rspHeader;
+  }
+
+  /**
+   * Check header whether it is right.
+   * 
+   * @return true when validating successfully or minor version not exist
+   */
+  public boolean isOkCustomHeaders() {
+    if (ObjectManagement.isStringEmpty(this.minorVersion)) {
+      logger.warn("X-MinorVersion is empty or null");
+      return true;
+    }
+
+    ApiVersionModel currVer = null;
+
+    // verList is an order array, which is from the first version to the latest version.
+    for (int index = 0; index < this.verLst.size(); index++) {
+      currVer = verLst.get(index);
+      if (currVer.getMajorVersion().equals(this.majorVersion) && currVer.getMinorVersion().equals(this.minorVersion)) {
+        return true;
+      }
+    }
+
+    logger.error("not find major version {} and minor version {}", this.majorVersion, this.minorVersion);
+    CLIENT_MINOR_VERSION_OK.set(Boolean.FALSE);
+    return false;
+  }
+}
\ No newline at end of file
diff --git a/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/util/ObjectManagement.java b/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/util/ObjectManagement.java
new file mode 100644
index 00000000..3f173d31
--- /dev/null
+++ b/standardization/api-custom-header/src/main/java/org/onap/dcaegen2/services/sdk/standardization/util/ObjectManagement.java
@@ -0,0 +1,53 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * org.onap.dcaegen2.services.sdk
+ * ================================================================================
+ * Copyright (C) 2019 vmware. 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.dcaegen2.services.sdk.standardization.util;
+
+
+import java.util.Collection;
+
+public final class ObjectManagement {
+
+  /**
+   * constructor that not permit to new object
+   */
+  private ObjectManagement() {
+
+  }
+
+  /**
+   * check string object if it is empty
+   * 
+   * @param str string object
+   * @return true when str is null or empty
+   */
+  public static boolean isStringEmpty(String str) {
+    return null == str || str.isEmpty();
+  }
+
+  /**
+   * check collection object if it is empty
+   * 
+   * @param c collection object
+   * @return true when c is null or empty
+   */
+  public static boolean isCollectionEmpty(Collection<?> c) {
+    return null == c || c.isEmpty();
+  }
+}
\ No newline at end of file