Relocation of DMI Stub to DMI Plugin

Move the DMI Stub into Plugin to use generated code classes
Changes:
-Created dmi-stub module
-Changed dmi-plugin-demo-and-csit-stub/dmi-plugin-demo-and-csit-stub-service/pom.xml dependency from cps-ncmp-rest to cps-ncmp-events
-Added extra required dependencies to dmi-plugin-demo-and-csit-stub/dmi-plugin-demo-and-csit-stub-service/pom.xml
-Included EventDateTimeFormatter in dmi-plugin-demo-and-csit-stub/dmi-plugin-demo-and-csit-stub-service/utils
-Included dmi-stub in pom.xml

Issue-ID: CPS-2145

Change-Id: Ibf0c9601564d3b38979c07c6a00d622cf763bf6b
Signed-off-by: egernug <gerard.nugent@est.tech>

6 files changed, 527 insertions, 0 deletions

diff --git a/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/controller/DmiRestStubController.java b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/controller/DmiRestStubController.java
new file mode 100644
index 00000000..fdc5af76
--- /dev/null
+++ b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/controller/DmiRestStubController.java
@@ -0,0 +1,323 @@
+/*
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2023-2024 Nordix Foundation
+ *  ================================================================================
+ *  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.
+ *
+ *  SPDX-License-Identifier: Apache-2.0
+ *  ============LICENSE_END=========================================================
+ */
+
+package org.onap.cps.ncmp.dmi.rest.stub.controller;
+
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import io.cloudevents.CloudEvent;
+import io.cloudevents.core.builder.CloudEventBuilder;
+import java.net.URI;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import java.util.stream.Collectors;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.json.simple.parser.JSONParser;
+import org.json.simple.parser.ParseException;
+import org.onap.cps.ncmp.dmi.rest.stub.model.data.operational.DataOperationRequest;
+import org.onap.cps.ncmp.dmi.rest.stub.model.data.operational.DmiDataOperationRequest;
+import org.onap.cps.ncmp.dmi.rest.stub.model.data.operational.DmiOperationCmHandle;
+import org.onap.cps.ncmp.dmi.rest.stub.utils.EventDateTimeFormatter;
+import org.onap.cps.ncmp.dmi.rest.stub.utils.ResourceFileReaderUtil;
+import org.onap.cps.ncmp.events.async1_0_0.Data;
+import org.onap.cps.ncmp.events.async1_0_0.DataOperationEvent;
+import org.onap.cps.ncmp.events.async1_0_0.Response;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.ApplicationContext;
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.ResourceLoader;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.kafka.core.KafkaTemplate;
+import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.PutMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestHeader;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("${rest.api.dmi-stub-base-path}")
+@RequiredArgsConstructor
+@Slf4j
+public class DmiRestStubController {
+
+    private static final String DEFAULT_TAG = "tagD";
+    private static final String dataOperationEventType = "org.onap.cps.ncmp.events.async1_0_0.DataOperationEvent";
+    private static final Map<String, String> moduleSetTagPerCmHandleId = new HashMap<>();
+    private final KafkaTemplate<String, CloudEvent> cloudEventKafkaTemplate;
+    private final ObjectMapper objectMapper;
+    private final ApplicationContext applicationContext;
+    @Value("${app.ncmp.async-m2m.topic}")
+    private String ncmpAsyncM2mTopic;
+    @Value("${delay.module-references-delay-ms}")
+    private long moduleReferencesDelayMs;
+    @Value("${delay.module-resources-delay-ms}")
+    private long moduleResourcesDelayMs;
+    @Value("${delay.data-for-cm-handle-delay-ms}")
+    private long dataForCmHandleDelayMs;
+
+    /**
+     * This code defines a REST API endpoint for adding new the module set tag mapping. The endpoint receives the
+     * cmHandleId and moduleSetTag as request body and add into moduleSetTagPerCmHandleId map with the provided
+     * values.
+     *
+     * @param requestBody map of cmHandleId and moduleSetTag
+     * @return a ResponseEntity object containing the updated moduleSetTagPerCmHandleId map as the response body
+     */
+    @PostMapping("/v1/tagMapping")
+    public ResponseEntity<Map<String, String>> addTagForMapping(@RequestBody final Map<String, String> requestBody) {
+        moduleSetTagPerCmHandleId.putAll(requestBody);
+        return new ResponseEntity<>(requestBody, HttpStatus.CREATED);
+    }
+
+    /**
+     * This code defines a GET endpoint of  module set tag mapping.
+     *
+     * @return The map represents the module set tag mapping.
+     */
+    @GetMapping("/v1/tagMapping")
+    public ResponseEntity<Map<String, String>> getTagMapping() {
+        return ResponseEntity.ok(moduleSetTagPerCmHandleId);
+    }
+
+    /**
+     * This code defines a GET endpoint of  module set tag by cm handle ID.
+     *
+     * @return The map represents the module set tag mapping filtered by cm handle ID.
+     */
+    @GetMapping("/v1/tagMapping/ch/{cmHandleId}")
+    public ResponseEntity<String> getTagMappingByCmHandleId(@PathVariable final String cmHandleId) {
+        return ResponseEntity.ok(moduleSetTagPerCmHandleId.get(cmHandleId));
+    }
+
+    /**
+     * This code defines a REST API endpoint for updating the module set tag mapping. The endpoint receives the
+     * cmHandleId and moduleSetTag as request body and updates the moduleSetTagPerCmHandleId map with the provided
+     * values.
+     *
+     * @param requestBody map of cmHandleId and moduleSetTag
+     * @return a ResponseEntity object containing the updated moduleSetTagPerCmHandleId map as the response body
+     */
+
+    @PutMapping("/v1/tagMapping")
+    public ResponseEntity<Map<String, String>> updateTagMapping(@RequestBody final Map<String, String> requestBody) {
+        moduleSetTagPerCmHandleId.putAll(requestBody);
+        return ResponseEntity.noContent().build();
+    }
+
+    /**
+     * It contains a method to delete an entry from the moduleSetTagPerCmHandleId map.
+     * The method takes a cmHandleId as a parameter and removes the corresponding entry from the map.
+     *
+     * @return a ResponseEntity containing the updated map.
+     */
+    @DeleteMapping("/v1/tagMapping/ch/{cmHandleId}")
+    public ResponseEntity<String> deleteTagMappingByCmHandleId(@PathVariable final String cmHandleId) {
+        moduleSetTagPerCmHandleId.remove(cmHandleId);
+        return ResponseEntity.ok(String.format("Mapping of %s is deleted successfully", cmHandleId));
+    }
+
+    /**
+     * Get all modules for given cm handle.
+     *
+     * @param cmHandleId              The identifier for a network function, network element, subnetwork,
+     *                                or any other cm object by managed Network CM Proxy
+     * @param moduleReferencesRequest module references request body
+     * @return ResponseEntity response entity having module response as json string.
+     */
+    @PostMapping("/v1/ch/{cmHandleId}/modules")
+    public ResponseEntity<String> getModuleReferences(@PathVariable("cmHandleId") final String cmHandleId,
+                                                      @RequestBody final Object moduleReferencesRequest) {
+        delay(moduleReferencesDelayMs);
+        try {
+            log.info("Incoming DMI request body: {}",
+                    objectMapper.writeValueAsString(moduleReferencesRequest));
+        } catch (final JsonProcessingException jsonProcessingException) {
+            log.info("Unable to parse dmi data operation request to json string");
+        }
+        final String moduleResponseContent = getModuleResourceResponse(cmHandleId,
+                "ModuleResponse.json");
+        log.info("cm handle: {} requested for modules", cmHandleId);
+        return ResponseEntity.ok(moduleResponseContent);
+    }
+
+    /**
+     * Retrieves module resources for a given cmHandleId.
+     *
+     * @param cmHandleId                 The identifier for a network function, network element, subnetwork,
+     *                                   or any other cm object by managed Network CM Proxy
+     * @param moduleResourcesReadRequest module resources read request body
+     * @return ResponseEntity response entity having module resources response as json string.
+     */
+    @PostMapping("/v1/ch/{cmHandleId}/moduleResources")
+    public ResponseEntity<String> retrieveModuleResources(
+            @PathVariable("cmHandleId") final String cmHandleId,
+            @RequestBody final Object moduleResourcesReadRequest) {
+        delay(moduleResourcesDelayMs);
+        final String moduleResourcesResponseContent = getModuleResourceResponse(cmHandleId,
+                "ModuleResourcesResponse.json");
+        log.info("cm handle: {} requested for modules resources", cmHandleId);
+        return ResponseEntity.ok(moduleResourcesResponseContent);
+    }
+
+    /**
+     * Create resource data from passthrough operational or running for a cm handle.
+     *
+     * @param cmHandleId              The identifier for a network function, network element, subnetwork,
+     *                                or any other cm object by managed Network CM Proxy
+     * @param datastoreName           datastore name
+     * @param resourceIdentifier      resource identifier
+     * @param options                 options
+     * @param topic                   client given topic name
+     * @return (@ code ResponseEntity) response entity
+     */
+    @PostMapping("/v1/ch/{cmHandleId}/data/ds/{datastoreName}")
+    public ResponseEntity<String> getResourceDataForCmHandle(
+            @PathVariable("cmHandleId") final String cmHandleId,
+            @PathVariable("datastoreName") final String datastoreName,
+            @RequestParam(value = "resourceIdentifier") final String resourceIdentifier,
+            @RequestParam(value = "options", required = false) final String options,
+            @RequestParam(value = "topic", required = false) final String topic,
+            @RequestHeader(value = "Authorization", required = false) final String authorization,
+            @RequestBody final String requestBody) {
+        log.info("DMI AUTH HEADER: {}", authorization);
+        delay(dataForCmHandleDelayMs);
+        log.info("Logging request body {}", requestBody);
+
+        final String sampleJson = ResourceFileReaderUtil.getResourceFileContent(applicationContext.getResource(
+                ResourceLoader.CLASSPATH_URL_PREFIX + "data/operational/ietf-network-topology-sample-rfc8345.json"));
+        return ResponseEntity.ok(sampleJson);
+    }
+
+    /**
+     * This method is not implemented for ONAP DMI plugin.
+     *
+     * @param topic                   client given topic name
+     * @param requestId               requestId generated by NCMP as an ack for client
+     * @param dmiDataOperationRequest list of operation details
+     * @return (@ code ResponseEntity) response entity
+     */
+    @PostMapping("/v1/data")
+    public ResponseEntity<Void> getResourceDataForCmHandleDataOperation(
+            @RequestParam(value = "topic") final String topic,
+            @RequestParam(value = "requestId") final String requestId,
+            @RequestBody final DmiDataOperationRequest dmiDataOperationRequest) {
+        delay(dataForCmHandleDelayMs);
+        try {
+            log.info("Request received from the NCMP to DMI Plugin: {}",
+                    objectMapper.writeValueAsString(dmiDataOperationRequest));
+        } catch (final JsonProcessingException jsonProcessingException) {
+            log.info("Unable to process dmi data operation request to json string");
+        }
+        dmiDataOperationRequest.getOperations().forEach(dmiDataOperation -> {
+            final DataOperationEvent dataOperationEvent = getDataOperationEvent(dmiDataOperation);
+            dmiDataOperation.getCmHandles().forEach(dmiOperationCmHandle -> {
+                log.info("Module Set Tag received: {}", dmiOperationCmHandle.getModuleSetTag());
+                dataOperationEvent.getData().getResponses().get(0).setIds(List.of(dmiOperationCmHandle.getId()));
+                final CloudEvent cloudEvent = buildAndGetCloudEvent(topic, requestId, dataOperationEvent);
+                cloudEventKafkaTemplate.send(ncmpAsyncM2mTopic, UUID.randomUUID().toString(), cloudEvent);
+            });
+        });
+        return new ResponseEntity<>(HttpStatus.ACCEPTED);
+    }
+
+    private CloudEvent buildAndGetCloudEvent(final String topic, final String requestId,
+                                             final DataOperationEvent dataOperationEvent) {
+        CloudEvent cloudEvent = null;
+        try {
+            cloudEvent = CloudEventBuilder.v1()
+                    .withId(UUID.randomUUID().toString())
+                    .withSource(URI.create("DMI"))
+                    .withType(dataOperationEventType)
+                    .withDataSchema(URI.create("urn:cps:" + dataOperationEventType + ":1.0.0"))
+                    .withTime(EventDateTimeFormatter.toIsoOffsetDateTime(
+                            EventDateTimeFormatter.getCurrentIsoFormattedDateTime()))
+                    .withData(objectMapper.writeValueAsBytes(dataOperationEvent))
+                    .withExtension("destination", topic)
+                    .withExtension("correlationid", requestId)
+                    .build();
+        } catch (final JsonProcessingException jsonProcessingException) {
+            log.error("Unable to parse event into bytes. cause : {}", jsonProcessingException.getMessage());
+        }
+        return cloudEvent;
+    }
+
+    private DataOperationEvent getDataOperationEvent(final DataOperationRequest dataOperationRequest) {
+        final Response response = new Response();
+
+        response.setOperationId(dataOperationRequest.getOperationId());
+        response.setStatusCode("0");
+        response.setStatusMessage("Successfully applied changes");
+        response.setIds(dataOperationRequest.getCmHandles().stream().map(DmiOperationCmHandle::getId)
+                .collect(Collectors.toList()));
+        response.setResourceIdentifier(dataOperationRequest.getResourceIdentifier());
+        response.setOptions(dataOperationRequest.getOptions());
+        final String ietfNetworkTopologySample = ResourceFileReaderUtil.getResourceFileContent(
+                applicationContext.getResource(ResourceLoader.CLASSPATH_URL_PREFIX
+                        + "data/operational/ietf-network-topology-sample-rfc8345.json"));
+        final JSONParser jsonParser = new JSONParser();
+        try {
+            response.setResult(jsonParser.parse(ietfNetworkTopologySample));
+        } catch (final ParseException parseException) {
+            log.error("Unable to parse event result as json object. cause : {}", parseException.getMessage());
+        }
+        final List<Response> responseList = new ArrayList<>(1);
+        responseList.add(response);
+        final Data data = new Data();
+        data.setResponses(responseList);
+        final DataOperationEvent dataOperationEvent = new DataOperationEvent();
+        dataOperationEvent.setData(data);
+        return dataOperationEvent;
+    }
+
+    private String getModuleResourceResponse(final String cmHandleId, final String moduleResponseType) {
+        if (moduleSetTagPerCmHandleId.isEmpty()) {
+            log.info("Using default module responses of type ietfYang");
+            return ResourceFileReaderUtil.getResourceFileContent(applicationContext.getResource(
+                    ResourceLoader.CLASSPATH_URL_PREFIX
+                            + String.format("module/ietfYang-%s", moduleResponseType)));
+        }
+        final String moduleSetTag = moduleSetTagPerCmHandleId.getOrDefault(cmHandleId, DEFAULT_TAG);
+        final String moduleResponseFilePath = String.format("module/%s-%s", moduleSetTag, moduleResponseType);
+        final Resource moduleResponseResource = applicationContext.getResource(
+                ResourceLoader.CLASSPATH_URL_PREFIX + moduleResponseFilePath);
+        log.info("Using module responses from : {}", moduleResponseFilePath);
+        return ResourceFileReaderUtil.getResourceFileContent(moduleResponseResource);
+    }
+
+    private void delay(final long milliseconds) {
+        try {
+            Thread.sleep(milliseconds);
+        } catch (final InterruptedException e) {
+            log.error("Thread sleep interrupted: {}", e.getMessage());
+            Thread.currentThread().interrupt();
+        }
+    }
+}
\ No newline at end of file
diff --git a/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/model/data/operational/DataOperationRequest.java b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/model/data/operational/DataOperationRequest.java
new file mode 100644
index 00000000..41077493
--- /dev/null
+++ b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/model/data/operational/DataOperationRequest.java
@@ -0,0 +1,39 @@
+/*
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2023 Nordix Foundation
+ *  ================================================================================
+ *  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.
+ *
+ *  SPDX-License-Identifier: Apache-2.0
+ *  ============LICENSE_END=========================================================
+ */
+
+package org.onap.cps.ncmp.dmi.rest.stub.model.data.operational;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+import java.util.ArrayList;
+import java.util.List;
+import lombok.Getter;
+import lombok.Setter;
+
+@JsonInclude(JsonInclude.Include.NON_NULL)
+@Setter
+@Getter
+public class DataOperationRequest {
+    private String operation;
+    private String operationId;
+    private String datastore;
+    private String options;
+    private String resourceIdentifier;
+    private List<DmiOperationCmHandle> cmHandles = new ArrayList<>();
+}
diff --git a/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/model/data/operational/DmiDataOperationRequest.java b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/model/data/operational/DmiDataOperationRequest.java
new file mode 100644
index 00000000..ae78c033
--- /dev/null
+++ b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/model/data/operational/DmiDataOperationRequest.java
@@ -0,0 +1,33 @@
+/*
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2023 Nordix Foundation
+ *  ================================================================================
+ *  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.
+ *
+ *  SPDX-License-Identifier: Apache-2.0
+ *  ============LICENSE_END=========================================================
+ */
+
+package org.onap.cps.ncmp.dmi.rest.stub.model.data.operational;
+
+import java.util.List;
+import lombok.Getter;
+import lombok.Setter;
+
+@Setter
+@Getter
+public class DmiDataOperationRequest {
+
+    private List<DataOperationRequest> operations;
+
+}
diff --git a/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/model/data/operational/DmiOperationCmHandle.java b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/model/data/operational/DmiOperationCmHandle.java
new file mode 100644
index 00000000..5cb24bc3
--- /dev/null
+++ b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/model/data/operational/DmiOperationCmHandle.java
@@ -0,0 +1,34 @@
+/*
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2023 Nordix Foundation
+ *  ================================================================================
+ *  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.
+ *
+ *  SPDX-License-Identifier: Apache-2.0
+ *  ============LICENSE_END=========================================================
+ */
+
+package org.onap.cps.ncmp.dmi.rest.stub.model.data.operational;
+
+import java.util.HashMap;
+import java.util.Map;
+import lombok.Getter;
+import lombok.Setter;
+
+@Setter
+@Getter
+public class DmiOperationCmHandle {
+    private String id;
+    private Map<String, String> cmHandleProperties = new HashMap<>();
+    private String moduleSetTag;
+}
diff --git a/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/utils/EventDateTimeFormatter.java b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/utils/EventDateTimeFormatter.java
new file mode 100644
index 00000000..7b6d1ab7
--- /dev/null
+++ b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/utils/EventDateTimeFormatter.java
@@ -0,0 +1,47 @@
+/*
+ * ============LICENSE_START=======================================================
+ * Copyright (C) 2022-2023 Nordix Foundation
+ * ================================================================================
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.cps.ncmp.dmi.rest.stub.utils;
+
+import java.time.OffsetDateTime;
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+import org.apache.commons.lang3.StringUtils;
+
+public interface EventDateTimeFormatter {
+
+    String ISO_TIMESTAMP_PATTERN = "yyyy-MM-dd'T'HH:mm:ss.SSSZ";
+
+    DateTimeFormatter ISO_TIMESTAMP_FORMATTER = DateTimeFormatter.ofPattern(ISO_TIMESTAMP_PATTERN);
+
+    /**
+     * Gets current date time.
+     *
+     * @return the current date time
+     */
+    static String getCurrentIsoFormattedDateTime() {
+        return ZonedDateTime.now().format(ISO_TIMESTAMP_FORMATTER);
+    }
+
+    static OffsetDateTime toIsoOffsetDateTime(final String dateTimestampAsString) {
+        return StringUtils.isNotBlank(dateTimestampAsString)
+                ? OffsetDateTime.parse(dateTimestampAsString, ISO_TIMESTAMP_FORMATTER) : null;
+    }
+}
diff --git a/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/utils/ResourceFileReaderUtil.java b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/utils/ResourceFileReaderUtil.java
new file mode 100644
index 00000000..0d2adee4
--- /dev/null
+++ b/dmi-stub/dmi-plugin-demo-and-csit-stub-service/src/main/java/org/onap/cps/ncmp/dmi/rest/stub/utils/ResourceFileReaderUtil.java
@@ -0,0 +1,51 @@
+/*
+ * ============LICENSE_START=======================================================
+ *  Copyright (C) 2023 Nordix Foundation
+ *  ================================================================================
+ *  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.
+ *
+ *  SPDX-License-Identifier: Apache-2.0
+ *  ============LICENSE_END=========================================================
+ */
+
+package org.onap.cps.ncmp.dmi.rest.stub.utils;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.core.io.Resource;
+import org.springframework.util.StreamUtils;
+
+/**
+ * Common convenience methods for reading resource file content.
+ */
+@Slf4j
+public class ResourceFileReaderUtil {
+
+    /**
+     * Converts a resource file content into string.
+     *
+     * @param fileClasspath to name of the file in test/resources
+     * @return the content of the file as a String
+     * @throws IOException when there is an IO issue
+     */
+    public static String getResourceFileContent(final Resource fileClasspath) {
+        String fileContent = null;
+        try {
+            fileContent = StreamUtils.copyToString(fileClasspath.getInputStream(), StandardCharsets.UTF_8);
+        } catch (final IOException ioException) {
+            log.debug("unable to read resource file content. cause : {}", ioException.getMessage());
+        }
+        return fileContent;
+    }
+}