| Warning |
|---|
This spike is a WIP |
| Table of Contents |
|---|
| Jira | ||||||
|---|---|---|---|---|---|---|
|
...
| Jira | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Issues/Decisions
...
| Color | Meaning |
|---|---|
| New/Open | |
| Reopened | |
| Agreed/Closed |
| # | Issue | Decision | Notes/Jira | Decision | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | What topic to use for client? | To be supplied by cient | Topic provided by client as a parameter which will be injected into our environment and used for asynchronous requests sent back to client. | 2 | What topic to use for private DMI-NCMP? | e.g. ncmp-async-private but decision needs to be made with current best practices. | 3 | Are adding a new REST endpoint for async or modifying an existing endpoint? | /ncmp/v1/data/ch/123ee5/ds/ncmp-datastore:*?topic=<topic-name> |
| Jira | ||||||
|---|---|---|---|---|---|---|
|
/ncmp/v1/data/ch/123ee5/ds/ncmp-datastore:*?topic=<topic-name>
Do we need to persist the generated requestID?
Async Request Option using Messaging
Proposed Diagram
| draw.io Diagram | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Kafka config & Implementation
Example Kafka Consumer Implementation from CPS-Temporal
The below code snippet taken from cps-temporal can be used in the same way in NCMP to listen to message from DMI substituting the topics and errorHandler
| Code Block | ||||||
|---|---|---|---|---|---|---|
| ||||||
/**
* Consume the specified event.
*
* @param cpsDataUpdatedEvent the data updated event to be consumed and persisted.
*/
@KafkaListener(topics = "${app.listener.data-updated.topic}", errorHandler = "dataUpdatedEventListenerErrorHandler")
public void consume(final CpsDataUpdatedEvent cpsDataUpdatedEvent) {
log.debug("Receiving {} ...", cpsDataUpdatedEvent);
// Validate event envelop
validateEventEnvelop(cpsDataUpdatedEvent);
// Map event to entity
final var networkData = this.cpsDataUpdatedEventMapper.eventToEntity(cpsDataUpdatedEvent);
log.debug("Persisting {} ...", networkData);
// Persist entity
final var persistedNetworkData = this.networkDataService.addNetworkData(networkData);
log.debug("Persisted {}", persistedNetworkData);
} |
Example Kafka Consumer Config from CPS-Temporal
Update: Toine Siebelink had a conversation with Tony Finnerty it has been agreed CPS is to configure a (temporary) dedicated client-topic as final destination for the async replies: we now want to propose to use a common ‘cps-broadcast’ topic which also will used for broadcasting messages like cm handles being added o removed etc. Still it is only a temporary solution until the client have a better way of declaring their own topics. It does not affect our proposed interfaces, just the name of the topic that will be accepted by NCMP (for now) --------------------------------------------------------------------------------------- Update: After discussion with Fiachra Corcoran regarding Kafka-strimzi it has been agreed that we will define a topic for client responses in advance (defined upfront). After release K it is envisioned that auto creation of topics will be disbaled by default thus the client will have to use our predefined topic. Agreement on topic name outstanding ---------------------------------------------------------------------------------------
| |||||||||||
| 2 | What topic to use for private DMI-NCMP? | Contact Fiachra Corcoran regarding ONAP conventions. Response was that there aren't any conventions to speak of but we would use dashes (i.e. my-new-topic) instead of dot notation (i.e. my.new.topic) for topic name | ncmp-async-m2m | ||||||||
| 3 | Are adding a new REST endpoint for async or modifying an existing endpoint? | To facilitate asynchronous requests to DMI we will need to either create a new endpoint or modify existing endpoint to include /async flag. The second solution may not be backwards compatible. However creating a new endpoint solely for a flag is also not ideal. We could add async to list of options (but this might interfere with the purpose of /options. Additionally, considered adding a new endpoint for async which simply re-routes the response to the original endpoint while adding the logic for OK response to the client. However, would this lead to a change in the schema? If so, would this be backwards compatible?
| /ncmp/v1/data/ch/123ee5/ds/ncmp-datastore:*?topic=<topic-name> | ||||||||
| 4 | Agree URL for async once #2 is clarified | CPS R10 Release Planning#NCMPRequirements #11. | /ncmp/v1/data/ch/123ee5/ds/ncmp-datastore:*?topic=<topic-name> | ||||||||
| 5 | Passthrough request need to be able to handle different response types (using accept header) but the async option would have a fixed and possibly different response type. | CPS R10 Release Planning#NCMPRequirements #11. | The async response can 'wrap' the native response inside a json object identical to the synchronous response | ||||||||
| 6 | Should we create a standalone app to demo or are tests sufficient? | CSIT tests may require more involved effort - perhaps we could add standalone app to nexus and use it as part of CSIT test? | See #13 | ||||||||
| 7 | Do we need to persist the generated requestID? | We should be be stateless | No - Further disc | ||||||||
| 8 | Error Reporting - Topic Correctness/Availability | At a minimum we should report to the client if a topic was not found or if the topic name was incorrect | In Scope | ||||||||
| 9 | Error Reporting - Kafka Issues | Issues such full buffer/queue, drop messages, failure not in scope | Out of scope | ||||||||
| 10 | Async Request Option using Messaging | See: https://wiki.onap.org/display/DW/CPS-821+Spike%3A+Support+Async+read-write+operations+on+CPS-NCMP+interface#CPS821Spike:SupportAsyncreadwriteoperationsonCPSNCMPinterface-AsyncRequestOptionusingMessaging(OutofScope) | Out of scope | ||||||||
| 11 | Do we actually require futures in this implementation proposal? | It could be argued that the need for futures is made redundant by the fact we call dmi from ncmp through rest and the response will be consumed via Kafka. What benefit would future give us in this case? | Not needed | ||||||||
| 12 | ID Generation | Which mechanism to use? Look at CPS-Temporal and follow to keep consistency | See: https://wiki.onap.org/display/DW/CPS-821+Spike%3A+Support+Async+read-write+operations+on+CPS-NCMP+interface#CPS821Spike:SupportAsyncreadwriteoperationsonCPSNCMPinterface-CanRobotFrameworkverifyKafkaEvents | ||||||||
| 13 | Can robot framework verify if Kafka events have been sent/received | This would be less work and overhead (rather than creating/.maintaining client app) Will need to verify if 3PP libraries are safe to introduce into codebase. If so, what is the process? Do they need to be FOSSed? | Integration testing should be carried out by a client of NCMP. Demo can be performed up the point NCMP produces message for the client. | ||||||||
| 14 | Can Webflux do this work with less code/impl? | Sourabh Sourabh suggested using this to compliment our existing approach. By adding webflux we add an event loop to synchronize and access I/O connections to the database. | No, It will compliment the design by adding an event loop for I/O synchronization and access. See: CPS-850 | ||||||||
| 15 | ONAP may be deprecating PLAINTEXT for Kafka. Strimzi Kafka might need to be used | No relevant information could be found relating to this. See: https://wiki.onap.org/display/DW/CPS-821+Spike%3A+Support+Async+read-write+operations+on+CPS-NCMP+interface#CPS821Spike:SupportAsyncreadwriteoperationsonCPSNCMPinterface-KafkaStrimziInvestigation | The underlying implementation won't be affected. The config will contain relevant configuration for protocol (e.g. PLAINTEXT, SASL) and connections. This information needs to be made configurable when implementing. | ||||||||
| 16 | Should we have something like the message count in the response or an indication of the last message at least.? | On the topic=Xyz async analysis, One item I forgot to mention was when a client might know when they have received the last response message for a request. If async there may be many responses (otherwise there's no need for async) Therefore should it not have something like the message count in it or an indication of the last message at least. | This is another step in an evolution of the product. Multiple response messages might become a necessity for asycnc bulk operations and maybe that is when we can discuss it in more detail. I don’t think it has to affect our current implementation additional field to handle that can always be added in a backward compatible way. | ||||||||
| 17 | Do we need Kafka messaging between DMI and NCMP? | This was discussed as it was argued that the client and CPS ecosystem is decoupled and async using only bus between ncmp and client. However, this would not rectify blocking calls between ncmp and dmi. | It was decided to have two separate kafka topics for client → ncmp & ncmp → dmi | ||||||||
| 18 | Can NCMP list all existing topics |
AC Point 3 : Topic does not exists (not allowed to create new topics, assuming NCMP can 'list' existing topics) Gareth Roper Need your suggestion. | |||||||||
| 19 |
Async: NCMP Rest impl. including Request ID generation | AC Points : 2. cm handle does not exists 3. No DMI registration for CM Handle | AC point 2 : We agreed to check only if cm handle exists. If cm does not exists will get Http status 404 as below. { AC point 3 . Is not valid. | ||||||||
| 20 | Client Kafka User & Privileges | After discussion with Fiachra Corcoran regarding Kafka-strimzi we will need to ensure client can access Kafka user and be allocated sufficient privileges (principle of least privilege) | |||||||||
| 21 | agree client response format | Message gets forwarded to original Client Topic | |||||||||
| 22 | Async Ack | { | Agreed & implemented |
Proposed Design
...
| draw.io Diagram | ||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
High-level Steps/Possible Tickets:
- Modify REST endpoint to include param topic (1)
- Add logic to send response and request (2a)
- Send request if async is implemented or NotSupportedException if not (2b)
- Add producer to DMI (implementation and config) (31 & 3b)
- Add consumer to NCMP (implementation and config) (4a)
- Add Producer to NCMP (implementation and config) (4b)
- Demo & Test (5)
Alternative Approaches
| # | Person | Approach |
|---|---|---|
| 1 | [Relates to point 3 from high-level steps] It would be good to have async implementation only dependent on NCMP. So that it does not break or work with only few DMI plugins. 2. No async request get lost because of pod restart or JVM crash. |
Proposed Message Format
...
| Info | ||||||||
|---|---|---|---|---|---|---|---|---|
| ||||||||
Legend
|
Success Scenario
| Info | ||||
|---|---|---|---|---|
| ||||
{ "eventId" : "9999", # some generic event uuid generated by DMI Plugin "eventType" : "org.onap.ncmp.async-request-response-event", # event type for async request response events (kieran mccarthy Who owns this schema? How do the schemas relate?)
|
| Info | ||||
|---|---|---|---|---|
| ||||
{ "eventId" : "33001", # some generic event uuid generated by NCMP "eventId" : "00001", # some generic event uuid generated by DMI Plugin
|
Failure Scenario
| Info | ||||
|---|---|---|---|---|
| ||||
{ "eventId" : "9999", # some generic event uuid generated by DMI Plugin |
| Info | ||||
|---|---|---|---|---|
| ||||
{ "eventId" : "33001", # some generic event uuid generated by NCMP "eventId" : "00001", # some generic event uuid generated by DMI Plugin
|
Sample Output
| Code Block | ||||||
|---|---|---|---|---|---|---|
| ||||||
{
"eventId": "c5c7c885-2e31-4951-aba5-3062889b8a7c",
"eventCorrelationId": "2539f8ac-b2c3-422d-bb75-b3f10d3d6216",
"eventTime": "2022-05-05T13:48:51.157+0000",
"eventSource": "org.onap.ncmp",
"eventSchema": "urn:cps:org.onap.cps:async-request-response-event-schema:v1",
"eventTarget": "my-topic-999",
"event": {
"response-data-schema": "urn:cps:org.onap.cps:async-request-response-event-schema:v1",
"response-status": "200",
"response-code": "SUCCESS",
"response-data": {
"ietf-netconf-monitoring:netconf-state": {
"schemas": {
"schema": [
{
"identifier": "ietf-tls-server",
"version": "2016-11-02",
"format": "ietf-netconf-monitoring:yang",
"namespace": "urn:ietf:params:xml:ns:yang:ietf-tls-server",
"location": [
"NETCONF"
]
},
...,
{
"identifier": "ietf-system",
"version": "2014-08-06",
"format": "ietf-netconf-monitoring:yin",
"namespace": "urn:ietf:params:xml:ns:yang:ietf-system",
"location": [
"NETCONF"
]
}
]
}
}
}
}
} |
| Code Block | ||||||
|---|---|---|---|---|---|---|
| ||||||
{
"eventId": "bfb86f3e-641b-4750-b3a0-d8d31f01a708",
"eventCorrelationId": "2539f8ac-b2c3-422d-bb75-b3f10d3d6216",
"eventTime": "2022-05-05T13:48:53.375+0000",
"eventSource": "org.onap.ncmp",
"eventSchema": "urn:cps:org.onap.cps:async-request-response-event-schema:v1",
"eventTarget": "my-topic-999",
"eventOrigin": {
"eventId": "c5c7c885-2e31-4951-aba5-3062889b8a7c",
"eventCorrelationId": "2539f8ac-b2c3-422d-bb75-b3f10d3d6216",
"eventTime": "2022-05-05T13:48:51.157+0000",
"eventSource": "org.onap.ncmp",
"eventSchema": "urn:cps:org.onap.cps:async-request-response-event-schema:v1",
"eventTarget": "my-topic-999"
},
"event": {
"response-data-schema": "urn:cps:org.onap.cps:async-request-response-event-schema:v1",
"response-status": "200",
"response-code": "SUCCESS",
"response-data": {
"ietf-netconf-monitoring:netconf-state": {
"schemas": {
"schema": [
{
"identifier": "ietf-tls-server",
"version": "2016-11-02",
"format": "ietf-netconf-monitoring:yang",
"namespace": "urn:ietf:params:xml:ns:yang:ietf-tls-server",
"location": [
"NETCONF"
]
},
...,
{
"identifier": "ietf-system",
"version": "2014-08-06",
"format": "ietf-netconf-monitoring:yin",
"namespace": "urn:ietf:params:xml:ns:yang:ietf-system",
"location": [
"NETCONF"
]
}
]
}
}
}
}
} |
Manual Testing
...
| Code Block | ||||||||
|---|---|---|---|---|---|---|---|---|
| ||||||||
{
"headers": {},
"body": {
"requestId": "0f574dfa-9c05-4899-9ae1-e6741f53c6d9"
},
"statusCode": "OK",
"statusCodeValue": 200
} |
| Code Block | ||||||||
|---|---|---|---|---|---|---|---|---|
| ||||||||
{
"logTimeStamp": "2022-05-10T11:16:27.123Z",
"logLevel": "INFO",
"principalId": "cpsuser",
"serviceName": "cps-application",
"message": "Async task completed successfully.",
"processId": "1",
"threadName": "ForkJoinPool.commonPool-worker-5",
"class": "o.o.c.n.r.executor.CpsNcmpTaskExecutor"
} |
| Code Block | ||||||||
|---|---|---|---|---|---|---|---|---|
| ||||||||
{
"eventId": "b2f629ae-ee90-44d9-97f9-500c8a595b6a",
"eventCorrelationId": "2243bbcd-b0b3-4aa5-9d53-41dc88a525a5",
"eventTime": "2022-05-10T08:39:37.597+0000",
"eventSource": "org.onap.ncmp",
"eventSchema": "urn:cps:org.onap.cps:async-request-response-event-schema:v1",
"eventTarget": "my-topic-999",
"eventContent": {
"response-data-schema": "urn:cps:org.onap.cps:async-request-response-event-schema:v1",
"response-status": "SUCCESS",
"response-code": "200",
"response-data": {
"ietf-netconf-monitoring:netconf-state": {
"schemas": {
"schema": [
{
"identifier": "ietf-tls-server",
"version": "2016-11-02",
"format": "ietf-netconf-monitoring:yang",
"namespace": "urn:ietf:params:xml:ns:yang:ietf-tls-server",
"location": [
"NETCONF"
]
},
{
"identifier": "nc-notifications",
"version": "2008-07-14",
"format": "ietf-netconf-monitoring:yang",
"namespace": "urn:ietf:params:xml:ns:netmod:notification",
"location": [
"NETCONF"
]
}
}
}
}
}
} |
| Code Block | ||||||||
|---|---|---|---|---|---|---|---|---|
| ||||||||
{
"eventId": "699da452-4131-4e55-b49a-50e0c5f0d641",
"eventCorrelationId": "efc17123-902a-4f50-8294-178a782b9102",
"eventTarget": "test-env-1",
"eventTime": "2022-05-10T11:16:27.427+0000",
"forwardedEvent": {
"eventId": "0f574dfa-9c05-4899-9ae1-e6741f53c6d9",
"eventCorrelationId": "efc17123-902a-4f50-8294-178a782b9102",
"eventTime": "2022-05-10T11:16:27.374+0000",
"eventSource": "org.onap.ncmp",
"eventSchema": "urn:cps:org.onap.cps:async-request-response-event-schema:v1",
"eventTarget": "test-env-1",
"response-data-schema": "urn:cps:org.onap.cps:async-request-response-event-schema:v1",
"response-status": "SUCCESS",
"response-code": "200",
"response-data": {
"ietf-netconf-monitoring:netconf-state": {
"schemas": {
"schema": [
{
"identifier": "ietf-tls-server",
"version": "2016-11-02",
"format": "ietf-netconf-monitoring:yang",
"namespace": "urn:ietf:params:xml:ns:yang:ietf-tls-server",
"location": [
"NETCONF"
]
},
{
"identifier": "nc-notifications",
"version": "2008-07-14",
"format": "ietf-netconf-monitoring:yang",
"namespace": "urn:ietf:params:xml:ns:netmod:notification",
"location": [
"NETCONF"
]
}
]
}
}
}
}
} |
Kafka config & Implementation
...
Example Kafka Consumer Implementation from CPS-Temporal
The below code snippet taken from cps-temporal can be used in the same way in NCMP to listen to message from DMI substituting the topics and errorHandler
| Code Block | ||||||
|---|---|---|---|---|---|---|
| ||||||
/**
* Consume the specified event.
*
* @param cpsDataUpdatedEvent the data updated event to be consumed and persisted.
*/
@KafkaListener(topics = "${app.listener.data-updated.topic}", errorHandler = "dataUpdatedEventListenerErrorHandler")
public void consume(final CpsDataUpdatedEvent cpsDataUpdatedEvent) {
log.debug("Receiving {} ...", cpsDataUpdatedEvent);
// Validate event envelop
validateEventEnvelop(cpsDataUpdatedEvent);
// Map event to entity
final var networkData = this.cpsDataUpdatedEventMapper.eventToEntity(cpsDataUpdatedEvent);
log.debug("Persisting {} ...", networkData);
// Persist entity
final var persistedNetworkData = this.networkDataService.addNetworkData(networkData);
log.debug("Persisted {}", persistedNetworkData);
} |
Example Kafka Consumer Config from CPS-Temporal
| Code Block | ||||||
|---|---|---|---|---|---|---|
| ||||||
# ============LICENSE_START=======================================================
# Copyright (c) 2021 Bell Canada.
# ================================================================================
# 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=========================================================
# Spring profile configuration for sasl ssl Kafka
spring:
kafka:
bootstrap-servers: ${KAFKA_BOOTSTRAP_SERVER}
security:
protocol: SASL_SSL
ssl:
trust-store-type: JKS
trust-store-location: ${KAFKA_SSL_TRUST_STORE_LOCATION}
trust-store-password: ${KAFKA_SSL_TRUST_STORE_PASSWORD}
properties:
sasl.mechanism: SCRAM-SHA-512
sasl.jaas.config: ${KAFKA_SASL_JAAS_CONFIG}
ssl.endpoint.identification.algorithm: |
Example Kafka Producer Implementation from CPS-NCMP
| Code Block | ||||||
|---|---|---|---|---|---|---|
| ||||||
/*
* ============LICENSE_START=======================================================
* Copyright (c) 2021 Bell Canada.
* ================================================================================
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* SPDX-License-Identifier: Apache-2.0
* ============LICENSE_END=========================================================
*/
package org.onap.cps.notification;
import lombok.extern.slf4j.Slf4j;
import org.checkerframework.checker.nullness.qual.NonNull;
import org.onap.cps.event.model.CpsDataUpdatedEvent;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.stereotype.Component;
@Component
@Slf4j
public class NotificationPublisher {
private KafkaTemplate<String, CpsDataUpdatedEvent> kafkaTemplate;
private String topicName;
/**
* Create an instance of Notification Publisher.
*
* @param kafkaTemplate kafkaTemplate is send event using kafka
* @param topicName topic, to which cpsDataUpdatedEvent is sent, is provided by setting
* 'notification.data-updated.topic' in the application properties
*/
@Autowired
public NotificationPublisher(
final KafkaTemplate<String, CpsDataUpdatedEvent> kafkaTemplate,
final @Value("${notification.data-updated.topic}") String topicName) {
this.kafkaTemplate = kafkaTemplate;
this.topicName = topicName;
}
/**
* Send event to Kafka with correct message key.
*
* @param cpsDataUpdatedEvent event to be sent to kafka
*/
public void sendNotification(@NonNull final CpsDataUpdatedEvent cpsDataUpdatedEvent) {
final var messageKey = cpsDataUpdatedEvent.getContent().getDataspaceName() + ","
+ cpsDataUpdatedEvent.getContent().getAnchorName();
log.debug("Data Updated event is being sent with messageKey: '{}' & body : {} ",
messageKey, cpsDataUpdatedEvent);
kafkaTemplate.send(topicName, messageKey, cpsDataUpdatedEvent);
}
}
|
Example Kafka Producer Config from CPS-NCMP
| Code Block | ||||||
|---|---|---|---|---|---|---|
| ||||||
spring:
kafka:
properties:
request.timeout.ms: 5000
retries: 1
max.block.ms: 10000
producer:
value-serializer: org.springframework.kafka.support.serializer.JsonSerializer
cliend-id: cps
consumer:
group-id: cps-test
auto-offset-reset: earliest
value-deserializer: org.springframework.kafka.support.serializer.JsonDeserializer
properties:
spring.json.value.default.type: org.onap.cps.event.model.CpsDataUpdatedEvent |
Example Kafka Docker-Compose
| Code Block | ||||||
|---|---|---|---|---|---|---|
| ||||||
kafka:
image: confluentinc/cp-kafka:6.1.1
container_name: kafka
ports:
- "19092:19092"
depends_on:
- zookeeper
environment:
KAFKA_BROKER_ID: 1
KAFKA_ZOOKEEPER_CONNECT: zookeeper:2181
KAFKA_ADVERTISED_LISTENERS: PLAINTEXT://kafka:9092,CONNECTIONS_FROM_HOST://localhost:19092
KAFKA_LISTENER_SECURITY_PROTOCOL_MAP: PLAINTEXT:PLAINTEXT,CONNECTIONS_FROM_HOST:PLAINTEXT
KAFKA_OFFSETS_TOPIC_REPLICATION_FACTOR: 1 |
Future or alternative (Out of Scope)
...
What are Futures?
A Java Future, java.util.concurrent.Future, represents the result of an asynchronous computation. When the asynchronous task is created, a Java Future object is returned. This Future object functions as a handle to the result of the asynchronous task. Once the asynchronous task completes, the result can be accessed via the Future object returned when the task was started
source: http://tutorials.jenkov.com/java-util-concurrent/java-future.html
CompletableFuture (Java8+)
Java 8 introduced the CompletableFuture class. Along with the Future interface, it also implemented the CompletionStage interface. This interface defines the contract for an asynchronous computation step that we can combine with other steps.
CompletableFuture is at the same time a building block and a framework, with about 50 different methods for composing, combining, and executing asynchronous computation steps and handling errors.
| Code Block | ||||||||
|---|---|---|---|---|---|---|---|---|
| ||||||||
CompletableFuture<Void> future = CompletableFuture.runAsync(() -> {
// Simulate a long-running Job
try {
TimeUnit.SECONDS.sleep(1);
} catch (InterruptedException e) {
throw new IllegalStateException(e);
}
System.out.println("I'll run in a separate thread than the main thread.");
}); |
source: https://www.callicoder.com/java-8-completablefuture-tutorial/
Alternatives - Thread
| Code Block | ||||||
|---|---|---|---|---|---|---|
| ||||||
int number = 20;
Thread newThread = new Thread(() -> {
System.out.println("Factorial of " + number + " is: " + factorial(number));
});
newThread.start(); |
| # | Type | Pros | Cons | Recommend |
|---|---|---|---|---|
| 1 | Future | Futures return value | Y | |
| 2 | Thread | threads does not return anything as the run() method returns void. We could possibly implement mechanism to trigger a response but this is unnecessary as futures do this | N |
Request ID Generation
...
| Type | Method | Ease of implementation | Decision |
|---|---|---|---|
| UUID | | Easy | ~ |
| Custom | We generate our own (example exists in NCMP (notificationPublisher - confrm)) | Medium | - |
| HTTP Request ID | Further investigation required | ~ | |
| Kafka Event ID | Further investigation required | ~ |
How do NCMP → CPS-Temporal perform ID Generation for Events?
| Code Block | ||||||
|---|---|---|---|---|---|---|
| ||||||
/*
* ============LICENSE_START=======================================================
* Copyright (c) 2021 Bell Canada.
* ================================================================================
* 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.notification;
import java.time.OffsetDateTime;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.Future;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import lombok.extern.slf4j.Slf4j;
import org.springframework.scheduling.annotation.Async;
import org.springframework.stereotype.Service;
@Service
@Slf4j
public class NotificationService {
private NotificationProperties notificationProperties;
private NotificationPublisher notificationPublisher;
private CpsDataUpdatedEventFactory cpsDataUpdatedEventFactory;
private NotificationErrorHandler notificationErrorHandler;
private List<Pattern> dataspacePatterns;
/**
* Create an instance of Notification Subscriber.
*
* @param notificationProperties properties for notification
* @param notificationPublisher notification Publisher
* @param cpsDataUpdatedEventFactory to create CPSDataUpdatedEvent
* @param notificationErrorHandler error handler
*/
public NotificationService(
final NotificationProperties notificationProperties,
final NotificationPublisher notificationPublisher,
final CpsDataUpdatedEventFactory cpsDataUpdatedEventFactory,
final NotificationErrorHandler notificationErrorHandler) {
log.info("Notification Properties {}", notificationProperties);
this.notificationProperties = notificationProperties;
this.notificationPublisher = notificationPublisher;
this.cpsDataUpdatedEventFactory = cpsDataUpdatedEventFactory;
this.notificationErrorHandler = notificationErrorHandler;
this.dataspacePatterns = getDataspaceFilterPatterns(notificationProperties);
}
private List<Pattern> getDataspaceFilterPatterns(final NotificationProperties notificationProperties) {
if (notificationProperties.isEnabled()) {
return Arrays.stream(notificationProperties.getFilters()
.getOrDefault("enabled-dataspaces", "")
.split(","))
.map(filterPattern -> Pattern.compile(filterPattern, Pattern.CASE_INSENSITIVE))
.collect(Collectors.toList());
} else {
return Collections.emptyList();
}
}
/**
* Process Data Updated Event and publishes the notification.
*
* @param dataspaceName dataspace name
* @param anchorName anchor name
* @param observedTimestamp observedTimestamp
* @return future
*/
@Async("notificationExecutor")
public Future<Void> processDataUpdatedEvent(final String dataspaceName, final String anchorName,
final OffsetDateTime observedTimestamp) {
log.debug("process data updated event for dataspace '{}' & anchor '{}'", dataspaceName, anchorName);
try {
if (shouldSendNotification(dataspaceName)) {
final var cpsDataUpdatedEvent =
cpsDataUpdatedEventFactory.createCpsDataUpdatedEvent(dataspaceName, anchorName, observedTimestamp);
log.debug("data updated event to be published {}", cpsDataUpdatedEvent);
notificationPublisher.sendNotification(cpsDataUpdatedEvent);
}
} catch (final Exception exception) {
/* All the exceptions are handled to not to propagate it to caller.
CPS operation should not fail if sending event fails for any reason.
*/
notificationErrorHandler.onException("Failed to process cps-data-updated-event.",
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# ============LICENSE_START======================================================= # Copyright (c) 2021 Bell Canada. # ================================================================================ # 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========================================================= # Spring profile configuration for sasl ssl Kafka spring: kafka: bootstrap-servers: ${KAFKA_BOOTSTRAP_SERVER} security: exception, protocol: SASL_SSLdataspaceName, anchorName); ssl:} return CompletableFuture.completedFuture(null); trust-store-type: JKS } /* trust-store-location: ${KAFKA_SSL_TRUST_STORE_LOCATION} trust-store-password: ${KAFKA_SSL_TRUST_STORE_PASSWORD}Add more complex rules based on dataspace and anchor later */ properties: private boolean shouldSendNotification(final String dataspaceName) { sasl.mechanism: SCRAM-SHA-512 return notificationProperties.isEnabled() && sasl.jaas.config: ${KAFKA_SASL_JAAS_CONFIG}dataspacePatterns.stream() ssl.endpoint.identification.algorithm: |
...
.anyMatch(pattern -> pattern.matcher(dataspaceName).find());
}
}
|
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/* * ============LICENSE_START======================================================= * Copyright (c) 2021 Bell Canada. * ================================================================================ * 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.notification; import lombok.extern.slf4j.Slf4j; import org.checkerframework.checker.nullness.qual.NonNull; import org.onap.cps.event.model.CpsDataUpdatedEvent; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.kafka.core.KafkaTemplate; import org.springframework.stereotype.Component; @Component @Slf4j public class NotificationPublisher { private KafkaTemplate<String, CpsDataUpdatedEvent> kafkaTemplate; private String topicName; /** * Create an instance of Notification Publisher. * * @param kafkaTemplate kafkaTemplate is send event using kafka * @param topicName topic, to which cpsDataUpdatedEvent is sent, is provided by setting public class NotificationPublisher { private KafkaTemplate<String, CpsDataUpdatedEvent> kafkaTemplate; private String topicName; /** * Create an instance of 'notification.data-updated.topic' in the application propertiesNotification Publisher. */ @Autowired * @param kafkaTemplate public NotificationPublisher( final KafkaTemplate<String, CpsDataUpdatedEvent> kafkaTemplate, kafkaTemplate is send event using kafka final @Value("${notification.data-updated.topic}") String topicName) { * @param topicName topic, to which cpsDataUpdatedEvent this.kafkaTemplate = kafkaTemplate; is sent, is provided by setting this.topicName* = topicName; } /** * Send event to Kafka with correct message key. * 'notification.data-updated.topic' in the application properties * @param cpsDataUpdatedEvent event to be sent to kafka/ @Autowired public */NotificationPublisher( public void sendNotification(@NonNull final CpsDataUpdatedEventKafkaTemplate<String, cpsDataUpdatedEvent)CpsDataUpdatedEvent> {kafkaTemplate, final var messageKey = cpsDataUpdatedEvent.getContent().getDataspaceName() + ","@Value("${notification.data-updated.topic}") String topicName) { this.kafkaTemplate + cpsDataUpdatedEvent.getContent().getAnchorName()= kafkaTemplate; log.debug("Data Updated event is being sent with messageKey: '{}' & body : {} ",this.topicName = topicName; } /** * Send event to Kafka with correct messageKey, cpsDataUpdatedEvent);message key. * kafkaTemplate.send(topicName, messageKey, cpsDataUpdatedEvent); } } |
Example Kafka Producer Config from CPS-NCMP (application.yml)
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|---|---|---|---|---|---|---|
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spring: kafka: properties: request.timeout.ms: 5000 * @param cpsDataUpdatedEvent event to be sent to kafka */ public void sendNotification(@NonNull final CpsDataUpdatedEvent cpsDataUpdatedEvent) { retries: 1 final var messageKey = max.block.ms: 10000 cpsDataUpdatedEvent.getContent().getDataspaceName() + "," producer: value-serializer: org.springframework.kafka.support.serializer.JsonSerializer+ cpsDataUpdatedEvent.getContent().getAnchorName(); cliend-id: cps consumer: group-id: cps-test log.debug("Data Updated event is being sent with messageKey: '{}' & body : {} ", auto-offset-reset: earliest value-deserializer: org.springframework.kafka.support.serializer.JsonDeserializermessageKey, cpsDataUpdatedEvent); properties: kafkaTemplate.send(topicName, messageKey, cpsDataUpdatedEvent); spring.json.value.default.type: org.onap.cps.event.model.CpsDataUpdatedEvent |
Example Kafka Docker-Compose
| Code Block | ||||||
|---|---|---|---|---|---|---|
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kafka:
image: confluentinc/cp-kafka:6.1.1
container_name: kafka
ports:
- "19092:19092"
depends_on:
- zookeeper
environment:
KAFKA_BROKER_ID: 1
KAFKA_ZOOKEEPER_CONNECT: zookeeper:2181
KAFKA_ADVERTISED_LISTENERS: PLAINTEXT://kafka:9092,CONNECTIONS_FROM_HOST://localhost:19092
KAFKA_LISTENER_SECURITY_PROTOCOL_MAP: PLAINTEXT:PLAINTEXT,CONNECTIONS_FROM_HOST:PLAINTEXT
KAFKA_OFFSETS_TOPIC_REPLICATION_FACTOR: 1 |
Future (or alternative)
What are Futures?
A Java Future, java.util.concurrent.Future, represents the result of an asynchronous computation. When the asynchronous task is created, a Java Future object is returned. This Future object functions as a handle to the result of the asynchronous task. Once the asynchronous task completes, the result can be accessed via the Future object returned when the task was started
source: http://tutorials.jenkov.com/java-util-concurrent/java-future.html
CompletableFuture (Java8+)
Java 8 introduced the CompletableFuture class. Along with the Future interface, it also implemented the CompletionStage interface. This interface defines the contract for an asynchronous computation step that we can combine with other steps.
CompletableFuture is at the same time a building block and a framework, with about 50 different methods for composing, combining, and executing asynchronous computation steps and handling errors.
| Code Block | ||||||||
|---|---|---|---|---|---|---|---|---|
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CompletableFuture<Void> future = CompletableFuture.runAsync(() -> {
// Simulate a long-running Job
try {
TimeUnit.SECONDS.sleep(1);
} catch (InterruptedException e) {
throw new IllegalStateException(e);
}
System.out.println("I'll run in a separate thread than the main thread.");
}); |
source: https://www.callicoder.com/java-8-completablefuture-tutorial/
Alternatives
Thread
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|---|---|---|---|---|---|---|
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int number = 20;
Thread newThread = new Thread(() -> {
System.out.println("Factorial of " + number + " is: " + factorial(number));
});
newThread.start(); |
...
}
} |
Async Request Option using Messaging (Out of Scope)
...
This was for a future completely message driven solution (for now we start with a REST request that will generate an async message eventually. In future we could also send a message that will trigger the same.
Webflux Investigation (Out of Scope)
...
| Info | ||||||||
|---|---|---|---|---|---|---|---|---|
This may need it's own study to determine improvements to operations like model sync. There is a spike planned to further investigate reactive programming in cps-core.
|
What is Webflux?
Spring WebFlux is a web framework that’s built on top of Project Reactor, to give you asynchronous I/O, and allow your application to perform better. The original web framework included in the Spring Framework, Spring Web MVC, was purpose-built for the Servlet API and Servlet containers. The reactive-stack web framework, Spring WebFlux, was added later in version 5.0. It is fully non-blocking, supports Reactive Streams back pressure, and runs on such servers as Netty, Undertow, and Servlet 3.1+ containers.
We suggest that you consider the following specific points:
If you have a Spring MVC application that works fine, there is no need to change. Imperative programming is the easiest way to write, understand, and debug code. You have maximum choice of libraries, since, historically, most are blocking.
In a microservice architecture, you can have a mix of applications with either Spring MVC or Spring WebFlux controllers or with Spring WebFlux functional endpoints. Having support for the same annotation-based programming model in both frameworks makes it easier to re-use knowledge while also selecting the right tool for the right job.
A simple way to evaluate an application is to check its dependencies. If you have blocking persistence APIs (JPA, JDBC) or networking APIs to use, Spring MVC is the best choice for common architectures at least. It is technically feasible with both Reactor and RxJava to perform blocking calls on a separate thread but you would not be making the most of a non-blocking web stack.
If you have a Spring MVC application with calls to remote services, try the reactive
WebClient. You can return reactive types (Reactor, RxJava, or other) directly from Spring MVC controller methods. The greater the latency per call or the interdependency among calls, the more dramatic the benefits. Spring MVC controllers can call other reactive components too.If you have a large team, keep in mind the steep learning curve in the shift to non-blocking, functional, and declarative programming. A practical way to start without a full switch is to use the reactive
WebClient. Beyond that, start small and measure the benefits. We expect that, for a wide range of applications, the shift is unnecessary. If you are unsure what benefits to look for, start by learning about how non-blocking I/O works (for example, concurrency on single-threaded Node.js) and its effects.Webflux supports:
- Annotation-based reactive components
- Functional routing and handling
Source: https://docs.spring.io/spring-framework/docs/current/reference/html/web-reactive.html
Pros & cons
| Pros | Cons |
|---|---|
|
|
Links to materials:
https://www.baeldung.com/spring-webflux
https://www.youtube.com/watch?v=1F10gr2pbvQ
Kafka Strimzi Investigation
...
Could not find relevant information for ONAP strimzi but there is a PoC to move CPS to Strimzi:
| Jira | ||||||
|---|---|---|---|---|---|---|
|
Can Robot Framework verify Kafka Events?
...
It does not appear to be possible to verify Kafka in Robotframework natively, but there are third party libraries that would aid in this:
- https://robooo.github.io/robotframework-ConfluentKafkaLibrary/
- https://github.com/opencord/kafka-robot
RequestID Generation
...
String uniqueID = UUID.randomUUID().toString();...
Async Request Option using Messaging (Out of Scope)
...
Demo/Test
...
Existing Groovy tests exist for Kafka in cps-service/src/test/groovy/org/onap/cps/notification
| Jira | ||||||
|---|---|---|---|---|---|---|
|
To facilitate demo and testing of this functionality a new standalone app will be required to act as client.
...
For a demo it will be sufficient to show that the response is being produced on the client topic.
The client should conduct integration testing.
References
...