From 078c34d0c2e439d8a148a2cd4d7545c6b7f56acb Mon Sep 17 00:00:00 2001 From: sebdet Date: Wed, 20 Jan 2021 23:02:17 +0100 Subject: First integration of Policy model PdpGroups Replacement of the PdpGroups clamp code by the one from policy model dependency. Issue-ID: POLICY-2924 Signed-off-by: sebdet Change-Id: I12c77704bba1c769dc2f307d91b759a3b645013f Signed-off-by: sebdet --- src/main/docker/frontend/nginx/default.conf | 2 +- .../clamp/clds/client/PolicyEngineServices.java | 20 +--- .../clamp/loop/template/PolicyModelsService.java | 58 ++++------ .../policy/clamp/policy/pdpgroup/PdpGroup.java | 92 --------------- .../clamp/policy/pdpgroup/PdpGroupsAnalyzer.java | 94 ++++++++++++++++ .../policy/clamp/policy/pdpgroup/PdpSubgroup.java | 56 --------- .../clamp/policy/pdpgroup/PolicyModelKey.java | 125 --------------------- .../resources/clds/camel/routes/policy-flows.xml | 38 ++++++- 8 files changed, 161 insertions(+), 324 deletions(-) delete mode 100644 src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpGroup.java create mode 100644 src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpGroupsAnalyzer.java delete mode 100644 src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpSubgroup.java delete mode 100644 src/main/java/org/onap/policy/clamp/policy/pdpgroup/PolicyModelKey.java (limited to 'src/main') diff --git a/src/main/docker/frontend/nginx/default.conf b/src/main/docker/frontend/nginx/default.conf index b15429c74..570806034 100644 --- a/src/main/docker/frontend/nginx/default.conf +++ b/src/main/docker/frontend/nginx/default.conf @@ -6,7 +6,7 @@ server { ssl_certificate_key /etc/ssl/clamp.key; ssl_verify_client optional_no_ca; location /restservices/clds/ { - proxy_pass https://clamp-backend:8443; + proxy_pass https://policy-clamp-backend:8443; proxy_set_header X-SSL-Cert $ssl_client_escaped_cert; } diff --git a/src/main/java/org/onap/policy/clamp/clds/client/PolicyEngineServices.java b/src/main/java/org/onap/policy/clamp/clds/client/PolicyEngineServices.java index bc6a68286..46c55ea45 100644 --- a/src/main/java/org/onap/policy/clamp/clds/client/PolicyEngineServices.java +++ b/src/main/java/org/onap/policy/clamp/clds/client/PolicyEngineServices.java @@ -2,7 +2,7 @@ * ============LICENSE_START======================================================= * ONAP CLAMP * ================================================================================ - * Copyright (C) 2020 AT&T Intellectual Property. All rights + * Copyright (C) 2020-2021 AT&T Intellectual Property. All rights * reserved. * ================================================================================ * Licensed under the Apache License, Version 2.0 (the "License"); @@ -39,7 +39,8 @@ import org.onap.policy.clamp.clds.sdc.controller.installer.BlueprintMicroService import org.onap.policy.clamp.clds.util.JsonUtils; import org.onap.policy.clamp.loop.template.PolicyModel; import org.onap.policy.clamp.loop.template.PolicyModelsService; -import org.onap.policy.clamp.policy.pdpgroup.PdpGroup; +import org.onap.policy.models.pdp.concepts.PdpGroup; +import org.onap.policy.models.pdp.concepts.PdpGroups; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component; import org.yaml.snakeyaml.DumperOptions; @@ -50,6 +51,8 @@ import org.yaml.snakeyaml.Yaml; * The class implements the communication with the Policy Engine to retrieve * policy models (tosca). It mainly delegates the physical calls to Camel * engine. + * It supports a retry mechanism for these calls, configurations can be specified in the + * application.properties "policy.retry.interval"(default 0) and "policy.retry.limit"(default 1). */ @Component public class PolicyEngineServices { @@ -192,18 +195,7 @@ public class PolicyEngineServices { return; } - JsonObject jsonObj = JsonUtils.GSON.fromJson(responseBody, JsonObject.class); - - List pdpGroupList = new LinkedList<>(); - JsonArray itemsArray = (JsonArray) jsonObj.get("groups"); - - for (com.google.gson.JsonElement jsonElement : itemsArray) { - JsonObject item = (JsonObject) jsonElement; - PdpGroup pdpGroup = JsonUtils.GSON.fromJson(item.toString(), PdpGroup.class); - pdpGroupList.add(pdpGroup); - } - - policyModelsService.updatePdpGroupInfo(pdpGroupList); + policyModelsService.updatePdpGroupInfo(JsonUtils.GSON.fromJson(responseBody, PdpGroups.class)); } private String callCamelRoute(Exchange exchange, String camelFlow, String logMsg) { diff --git a/src/main/java/org/onap/policy/clamp/loop/template/PolicyModelsService.java b/src/main/java/org/onap/policy/clamp/loop/template/PolicyModelsService.java index 8670ab73e..f0830360e 100644 --- a/src/main/java/org/onap/policy/clamp/loop/template/PolicyModelsService.java +++ b/src/main/java/org/onap/policy/clamp/loop/template/PolicyModelsService.java @@ -2,7 +2,7 @@ * ============LICENSE_START======================================================= * ONAP CLAMP * ================================================================================ - * Copyright (C) 2020 AT&T Intellectual Property. All rights + * Copyright (C) 2020-2021 AT&T Intellectual Property. All rights * reserved. * ================================================================================ * Licensed under the Apache License, Version 2.0 (the "License"); @@ -30,13 +30,18 @@ import java.util.Collections; import java.util.List; import org.onap.policy.clamp.clds.tosca.ToscaSchemaConstants; import org.onap.policy.clamp.clds.tosca.ToscaYamlToJsonConvertor; -import org.onap.policy.clamp.policy.pdpgroup.PdpGroup; +import org.onap.policy.clamp.policy.pdpgroup.PdpGroupsAnalyzer; import org.onap.policy.clamp.util.SemanticVersioning; +import org.onap.policy.models.pdp.concepts.PdpGroup; +import org.onap.policy.models.pdp.concepts.PdpGroups; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Propagation; import org.springframework.transaction.annotation.Transactional; +/** + * This class contains the methods to access the policyModel object in db. + */ @Service public class PolicyModelsService { private final PolicyModelsRepository policyModelsRepository; @@ -44,7 +49,7 @@ public class PolicyModelsService { @Autowired public PolicyModelsService(PolicyModelsRepository policyModelrepo, - ToscaYamlToJsonConvertor convertor) { + ToscaYamlToJsonConvertor convertor) { policyModelsRepository = policyModelrepo; toscaYamlToJsonConvertor = convertor; } @@ -78,31 +83,31 @@ public class PolicyModelsService { public PolicyModel createNewPolicyModelFromTosca(String policyModelTosca) { JsonObject jsonObject = toscaYamlToJsonConvertor.validateAndConvertToJson(policyModelTosca); String policyModelTypeFromTosca = toscaYamlToJsonConvertor.getValueFromMetadata(jsonObject, - ToscaSchemaConstants.METADATA_POLICY_MODEL_TYPE); + ToscaSchemaConstants.METADATA_POLICY_MODEL_TYPE); Iterable models = getAllPolicyModelsByType(policyModelTypeFromTosca); Collections.sort((List) models); PolicyModel newPolicyModel = new PolicyModel(policyModelTypeFromTosca, policyModelTosca, - SemanticVersioning.incrementMajorVersion(((ArrayList) models).isEmpty() ? null - : ((ArrayList) models).get(0).getVersion()), - toscaYamlToJsonConvertor.getValueFromMetadata(jsonObject, - ToscaSchemaConstants.METADATA_ACRONYM)); + SemanticVersioning.incrementMajorVersion(((ArrayList) models).isEmpty() ? null + : ((ArrayList) models).get(0).getVersion()), + toscaYamlToJsonConvertor.getValueFromMetadata(jsonObject, + ToscaSchemaConstants.METADATA_ACRONYM)); return saveOrUpdatePolicyModel(newPolicyModel); } /** * Update an existing Tosca Policy Model. * - * @param policyModelType The policy Model type in Tosca yaml + * @param policyModelType The policy Model type in Tosca yaml * @param policyModelVersion The policy Version to update - * @param policyModelTosca The Policy Model tosca + * @param policyModelTosca The Policy Model tosca * @return The Policy Model updated */ public PolicyModel updatePolicyModelTosca(String policyModelType, String policyModelVersion, - String policyModelTosca) { + String policyModelTosca) { JsonObject jsonObject = toscaYamlToJsonConvertor.validateAndConvertToJson(policyModelTosca); PolicyModel thePolicyModel = getPolicyModel(policyModelType, policyModelVersion); thePolicyModel.setPolicyAcronym(toscaYamlToJsonConvertor.getValueFromMetadata(jsonObject, - ToscaSchemaConstants.METADATA_ACRONYM)); + ToscaSchemaConstants.METADATA_ACRONYM)); thePolicyModel.setPolicyModelTosca(policyModelTosca); return saveOrUpdatePolicyModel(thePolicyModel); } @@ -126,13 +131,13 @@ public class PolicyModelsService { /** * Retrieves the Tosca model Yaml string. * - * @param type The Policy Model Type + * @param type The Policy Model Type * @param version The policy model version * @return The Tosca model Yaml string */ public String getPolicyModelTosca(String type, String version) { return policyModelsRepository.findById(new PolicyModelId(type, version)) - .orElse(new PolicyModel()).getPolicyModelTosca(); + .orElse(new PolicyModel()).getPolicyModelTosca(); } /** @@ -148,26 +153,11 @@ public class PolicyModelsService { /** * Update the Pdp Group info in Policy Model DB. * - * @param pdpGroupList The list of Pdp Group info received from Policy Engine + * @param pdpGroups The list of Pdp Group info received from Policy Engine */ - public void updatePdpGroupInfo(List pdpGroupList) { - List policyModelList = policyModelsRepository.findAll(); - for (PolicyModel policyModel : policyModelList) { - JsonArray supportedPdpGroups = new JsonArray(); - for (PdpGroup pdpGroup : pdpGroupList) { - JsonObject supportedPdpGroup = pdpGroup.getSupportedSubgroups( - policyModel.getPolicyModelType(), policyModel.getVersion()); - if (supportedPdpGroup != null) { - supportedPdpGroups.add(supportedPdpGroup); - } - } - - if (supportedPdpGroups.size() > 0) { - JsonObject supportedPdpJson = new JsonObject(); - supportedPdpJson.add("supportedPdpGroups", supportedPdpGroups); - policyModel.setPolicyPdpGroup(supportedPdpJson); - policyModelsRepository.saveAndFlush(policyModel); - } - } + public void updatePdpGroupInfo(PdpGroups pdpGroups) { + List policyModelsList = policyModelsRepository.findAll(); + PdpGroupsAnalyzer.updatePdpGroup(policyModelsList, pdpGroups); + this.policyModelsRepository.saveAll(policyModelsList); } } diff --git a/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpGroup.java b/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpGroup.java deleted file mode 100644 index 9cbeec109..000000000 --- a/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpGroup.java +++ /dev/null @@ -1,92 +0,0 @@ -/*- - * ============LICENSE_START======================================================= - * ONAP CLAMP - * ================================================================================ - * Copyright (C) 2020 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.policy.clamp.policy.pdpgroup; - -import com.google.gson.JsonArray; -import com.google.gson.JsonObject; -import com.google.gson.annotations.Expose; -import java.util.List; - -/** - * This class maps the get Pdp Group response to a nice pojo. - */ -public class PdpGroup { - - @Expose - private String name; - - @Expose - private String pdpGroupState; - - @Expose - private List pdpSubgroups; - - public String getName() { - return name; - } - - public void setName(String name) { - this.name = name; - } - - public String getPdpGroupState() { - return pdpGroupState; - } - - public void setPdpGroupState(String pdpGroupState) { - this.pdpGroupState = pdpGroupState; - } - - public List getPdpSubgroups() { - return pdpSubgroups; - } - - public void setPdpSubgroups(List pdpSubgroups) { - this.pdpSubgroups = pdpSubgroups; - } - - /** - * Get supported subGroups based on the defined policy type and version. - * @param policyType The policy type - * @param version The version - * @return The supported subGroup list in Json format - */ - public JsonObject getSupportedSubgroups(String policyType, String version) { - if (!pdpGroupState.equalsIgnoreCase("ACTIVE")) { - return null; - } - JsonArray supportedSubgroups = new JsonArray(); - for (PdpSubgroup subGroup : pdpSubgroups) { - if (subGroup.getSupportedPolicyTypes().contains(new PolicyModelKey(policyType, version))) { - supportedSubgroups.add(subGroup.getPdpType()); - } - } - if (supportedSubgroups.size() > 0) { - JsonObject supportedPdpGroup = new JsonObject(); - supportedPdpGroup.add(this.name, supportedSubgroups); - return supportedPdpGroup; - } - return null; - } -} diff --git a/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpGroupsAnalyzer.java b/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpGroupsAnalyzer.java new file mode 100644 index 000000000..51cdb149e --- /dev/null +++ b/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpGroupsAnalyzer.java @@ -0,0 +1,94 @@ +/*- + * ============LICENSE_START======================================================= + * ONAP CLAMP + * ================================================================================ + * Copyright (C) 2021 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.policy.clamp.policy.pdpgroup; + +import com.google.gson.JsonArray; +import com.google.gson.JsonObject; +import java.util.List; +import java.util.Objects; +import java.util.stream.Collectors; +import org.onap.policy.clamp.loop.template.PolicyModel; +import org.onap.policy.models.pdp.concepts.PdpGroup; +import org.onap.policy.models.pdp.concepts.PdpGroups; +import org.onap.policy.models.pdp.concepts.PdpSubGroup; +import org.onap.policy.models.pdp.enums.PdpState; +import org.onap.policy.models.tosca.authorative.concepts.ToscaPolicyTypeIdentifier; +import org.onap.sdc.toscaparser.api.elements.PolicyType; + +/** + * This is an utility class to do searching in pdp groups. + */ +public class PdpGroupsAnalyzer { + /** + * Get supported subGroups based on the defined policy type and version for s specific PDPgroup. + * It returns null if the Group is not ACTIVE or if the policytype/version has not been found in the PDPSubgroups. + * + * @param pdpGroup The pdpGroup that must be analyzed + * @param policyType The policy type + * @param version The version + * @return The supported subGroups list in Json format + * @see org.onap.policy.models.pdp.concepts.PdpGroup + * @see org.onap.policy.models.pdp.enums.PdpState + */ + private static JsonObject getSupportedSubgroups(PdpGroup pdpGroup, String policyType, String version) { + if (!PdpState.ACTIVE.equals(pdpGroup.getPdpGroupState())) { + return null; + } + JsonObject supportedPdpGroup = new JsonObject(); + JsonArray supportedSubgroups = new JsonArray(); + supportedPdpGroup.add(pdpGroup.getName(), supportedSubgroups); + pdpGroup.getPdpSubgroups().stream().forEach(pdpSubGroup -> { + if (pdpSubGroup.getSupportedPolicyTypes().stream().anyMatch(policyTypeIdentifier -> + policyType.matches(policyTypeIdentifier.getName().replace(".", "\\.").replace("*", ".*")) + && version.equals(policyTypeIdentifier.getVersion()))) { + supportedSubgroups.add(pdpSubGroup.getPdpType()); + } + }); + if (supportedSubgroups.size() == 0) { + return null; + } + return supportedPdpGroup; + } + + /** + * This method updates each element in the policyModelsList given in argument based on the pdpGroups given. + * + * @param policyModelsList The list of Policy Models where each PolicyModel will be updated + * @param pdpGroups The PdpGroups containing all PDP group definition + */ + public static void updatePdpGroup(List policyModelsList, PdpGroups pdpGroups) { + policyModelsList.parallelStream().forEach(policyModel -> { + JsonObject jsonResult = new JsonObject(); + JsonArray supportedPdpGroups = new JsonArray(); + jsonResult.add("supportedPdpGroups", supportedPdpGroups); + policyModel.setPolicyPdpGroup(jsonResult); + pdpGroups.getGroups().stream().map(pdpGroup -> PdpGroupsAnalyzer.getSupportedSubgroups(pdpGroup, + policyModel.getPolicyModelType(), policyModel.getVersion())).filter(Objects::nonNull) + .forEach(jsonPdpGroup -> supportedPdpGroups.add(jsonPdpGroup)); + if (supportedPdpGroups.size() == 0) { + policyModel.setPolicyPdpGroup(null); + } + }); + } +} \ No newline at end of file diff --git a/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpSubgroup.java b/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpSubgroup.java deleted file mode 100644 index 890f90775..000000000 --- a/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PdpSubgroup.java +++ /dev/null @@ -1,56 +0,0 @@ -/*- - * ============LICENSE_START======================================================= - * ONAP CLAMP - * ================================================================================ - * Copyright (C) 2020 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.policy.clamp.policy.pdpgroup; - -import com.google.gson.annotations.Expose; -import java.util.List; - -/** - * This class maps the Policy get PDP Group response to a nice pojo. - */ -public class PdpSubgroup { - - @Expose - private String pdpType; - - @Expose - private List supportedPolicyTypes; - - public String getPdpType() { - return pdpType; - } - - public void setPdpType(String pdpType) { - this.pdpType = pdpType; - } - - public List getSupportedPolicyTypes() { - return supportedPolicyTypes; - } - - public void setSupportedPolicyTypes(List supportedPolicyTypes) { - this.supportedPolicyTypes = supportedPolicyTypes; - } - -} diff --git a/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PolicyModelKey.java b/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PolicyModelKey.java deleted file mode 100644 index df92bfdf9..000000000 --- a/src/main/java/org/onap/policy/clamp/policy/pdpgroup/PolicyModelKey.java +++ /dev/null @@ -1,125 +0,0 @@ -/*- - * ============LICENSE_START======================================================= - * ONAP CLAMP - * ================================================================================ - * Copyright (C) 2020 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.policy.clamp.policy.pdpgroup; - -import com.google.gson.annotations.Expose; -import java.io.Serializable; - -public class PolicyModelKey implements Serializable { - - /** - * The serial version ID. - */ - private static final long serialVersionUID = 3307410842013230886L; - - @Expose - private String name; - - @Expose - private String version; - - /** - * Constructor. - */ - public PolicyModelKey(String name, String version) { - this.name = name; - this.version = version; - } - - /** - * name getter. - * - * @return the name - */ - public String getName() { - return name; - } - - /** - * name setter. - * - * @param name the name to set - */ - public void setName(String name) { - this.name = name; - } - - /** - * version getter. - * - * @return the version - */ - public String getVersion() { - return version; - } - - /** - * version setter. - * - * @param version the version to set - */ - public void setVersion(String version) { - this.version = version; - } - - @Override - public int hashCode() { - final int prime = 31; - int result = 1; - result = prime * result + ((name == null) ? 0 : name.hashCode()); - result = prime * result + ((version == null) ? 0 : version.hashCode()); - return result; - } - - @Override - public boolean equals(Object obj) { - if (this == obj) { - return true; - } - if (obj == null) { - return false; - } - if (getClass() != obj.getClass()) { - return false; - } - PolicyModelKey other = (PolicyModelKey) obj; - if (name == null) { - if (other.name != null) { - return false; - } - } else if (!name.equals(other.name)) { - if (!name.matches(other.name)) { - return false; - } - } - if (version == null) { - if (other.version != null) { - return false; - } - } else if (!version.equals(other.version)) { - return false; - } - return true; - } -} diff --git a/src/main/resources/clds/camel/routes/policy-flows.xml b/src/main/resources/clds/camel/routes/policy-flows.xml index 0ee386eb4..4d1eba614 100644 --- a/src/main/resources/clds/camel/routes/policy-flows.xml +++ b/src/main/resources/clds/camel/routes/policy-flows.xml @@ -109,7 +109,7 @@ + uri="{{clamp.config.policy.pap.url}}/policy/pap/v1/policies/deployed/${exchangeProperty[policyName]}/1.0.0?bridgeEndpoint=true&useSystemProperties=true&throwExceptionOnFailure=${exchangeProperty[raiseHttpExceptionFlag]}&authMethod=Basic&authUsername={{clamp.config.policy.pap.userName}}&authPassword={{clamp.config.policy.pap.password}}&httpClient.connectTimeout=10000&httpClient.socketTimeout=20000&authenticationPreemptive=true&connectionClose=true"/> java.lang.Exception @@ -427,7 +427,41 @@ + uri="{{clamp.config.policy.pap.url}}/policy/pap/v1/pdps?bridgeEndpoint=true&useSystemProperties=true&throwExceptionOnFailure=${exchangeProperty[raiseHttpExceptionFlag]}&authMethod=Basic&authUsername={{clamp.config.policy.pap.userName}}&authPassword={{clamp.config.policy.pap.password}}&httpClient.connectTimeout=10000&httpClient.socketTimeout=20000&authenticationPreemptive=true&connectionClose=true"/> + + + + + + + + + + + + + + GET + + + ${exchangeProperty[X-ONAP-RequestID]} + + + + ${exchangeProperty[X-ONAP-InvocationID]} + + + + ${exchangeProperty[X-ONAP-PartnerName]} + + + + -- cgit 1.2.3-korg