Mongo DB View
Purpose#
The Mongo View is component responsible for creating read-projections of tasks and business data entries. It implements the Taskpool and Datapool View API and persists the projection as document collections in a Mongo database.
Features#
- stores JSON document representation of enriched tasks, process definitions and business data entries
- provides single query API
- provides subscription query API (reactive)
- switchable subscription query API (AxonServer or MongoDB ChangeStream)
Warning
Mongo DB View is currently NOT SUPPORTING Revision Aware queries.
Configuration options#
In order to activate the Mongo implementation, please include the following dependency on your classpath:
<dependency>
<groupId>io.holunda.polyflow</groupId>
<artifactId>polyflow-view-mongo</artifactId>
<version>${polyflow.version}</version>
</dependency>
The implementation relies on Spring Data Mongo and needs to activate those. Please add the following annotation to any class marked as Spring Configuration loaded during initialization:
@Configuration
@EnablePolyflowMongoView
@Import({
org.springframework.boot.autoconfigure.mongo.MongoAutoConfiguration.class,
org.springframework.boot.autoconfigure.mongo.MongoReactiveAutoConfiguration.class,
org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration.class,
org.springframework.boot.autoconfigure.data.mongo.MongoReactiveDataAutoConfiguration.class
})
public class MyViewConfiguration {
}
In addition, configure a Mongo connection to database called tasks-payload using application.properties or
application.yaml:
spring:
data:
mongodb:
database: tasks-payload
host: localhost
port: 27017
The view implementation provides runtime details using standard logging facility. If you
want to increase the logging level, please set up it e.g. in your application.yaml:
logging.level.io.holunda.polyflow.view.mongo: DEBUG
For further configuration, please check Mongo DB View Configuration
Collections#
The Mongo View uses several collections to store the results. These are:
- data-entries: collection for business data entries
- processes: collection for process definitions
- tasks: collection for user tasks
- tracking-tokens: collection for Axon Tracking Tokens
Data Entries Collection#
The data entries collection stores the business data entries in a uniform Datapool format. Here is an example:
{
"_id" : "io.holunda.camunda.taskpool.example.ApprovalRequest#2db47ced-83d4-4c74-a644-44dd738935f8",
"entryType" : "io.holunda.camunda.taskpool.example.ApprovalRequest",
"payload" : {
"amount" : "900.00",
"subject" : "Advanced training",
"currency" : "EUR",
"id" : "2db47ced-83d4-4c74-a644-44dd738935f8",
"applicant" : "hulk"
},
"correlations" : {},
"type" : "Approval Request",
"name" : "AR 2db47ced-83d4-4c74-a644-44dd738935f8",
"applicationName" : "example-process-approval",
"description" : "Advanced training",
"state" : "Submitted",
"statusType" : "IN_PROGRESS",
"authorizedUsers" : [
"gonzo",
"hulk"
],
"authorizedGroups" : [],
"deleted" : false,
"protocol" : [
{
"time" : ISODate("2019-08-21T09:12:54.779Z"),
"statusType" : "PRELIMINARY",
"state" : "Draft",
"username" : "gonzo",
"logMessage" : "Draft created.",
"logDetails" : "Request draft on behalf of hulk created."
},
{
"time" : ISODate("2019-08-21T09:12:55.060Z"),
"statusType" : "IN_PROGRESS",
"state" : "Submitted",
"username" : "gonzo",
"logMessage" : "New approval request submitted."
}
]
}
Tasks Collections#
Tasks are stored in the following format (an example):
{
"_id" : "dc1abe54-c3f3-11e9-86e8-4ab58cfe8f17",
"sourceReference" : {
"_id" : "dc173bca-c3f3-11e9-86e8-4ab58cfe8f17",
"executionId" : "dc1a9742-c3f3-11e9-86e8-4ab58cfe8f17",
"definitionId" : "process_approve_request:1:91f2ff26-a64b-11e9-b117-3e6d125b91e2",
"definitionKey" : "process_approve_request",
"name" : "Request Approval",
"applicationName" : "example-process-approval",
"_class" : "process"
},
"taskDefinitionKey" : "user_approve_request",
"payload" : {
"request" : "2db47ced-83d4-4c74-a644-44dd738935f8",
"originator" : "gonzo"
},
"correlations" : {
"io:holunda:camunda:taskpool:example:ApprovalRequest" : "2db47ced-83d4-4c74-a644-44dd738935f8",
"io:holunda:camunda:taskpool:example:User" : "gonzo"
},
"dataEntriesRefs" : [
"io.holunda.camunda.taskpool.example.ApprovalRequest#2db47ced-83d4-4c74-a644-44dd738935f8",
"io.holunda.camunda.taskpool.example.User#gonzo"
],
"businessKey" : "2db47ced-83d4-4c74-a644-44dd738935f8",
"name" : "Approve Request",
"description" : "Please approve request 2db47ced-83d4-4c74-a644-44dd738935f8 from gonzo on behalf of hulk.",
"formKey" : "approve-request",
"priority" : 23,
"createTime" : ISODate("2019-08-21T09:12:54.872Z"),
"candidateUsers" : [
"fozzy",
"gonzo"
],
"candidateGroups" : [],
"dueDate" : ISODate("2019-06-26T07:55:00.000Z"),
"followUpDate" : ISODate("2023-06-26T07:55:00.000Z"),
"deleted" : false
}
Process Collection#
Process definition collection allows for storage of startable process definitions, deployed in a Camunda Engine. This information is in particular interesting, if you are building a process-starter component and want to react dynamically on processes deployed in your landscape.
{
"_id" : "process_approve_request:1:91f2ff26-a64b-11e9-b117-3e6d125b91e2",
"processDefinitionKey" : "process_approve_request",
"processDefinitionVersion" : 1,
"applicationName" : "example-process-approval",
"processName" : "Request Approval",
"processDescription" : "This is a wonderful process.",
"formKey" : "start-approval",
"startableFromTasklist" : true,
"candidateStarterUsers" : [],
"candidateStarterGroups" : [
"muppetshow",
"avengers"
]
}
Tracking Token Collection#
The Axon Tracking Token reflects the index of the event processed by the Mongo View and is stored in the following format:
{
"_id" : ObjectId("5d2b45d6a9ca33042abea23b"),
"processorName" : "io.holunda.camunda.taskpool.view.mongo.service",
"segment" : 0,
"owner" : "18524@blackstar",
"timestamp" : NumberLong(1566379093564),
"token" : { "$binary" : "PG9yZy5heG9uZnJhbWV3b3JrLmV2ZW50aGFuZGxpbmcuR2xvYmFsU2VxdWVuY2VUcmFja2luZ1Rva2VuPjxnbG9iYWxJbmRleD40NDwvZ2xvYmFsSW5kZXg+PC9vcmcuYXhvbmZyYW1ld29yay5ldmVudGhhbmRsaW5nLkdsb2JhbFNlcXVlbmNlVHJhY2tpbmdUb2tlbj4=", "$type" : "00" },
"tokenType" : "org.axonframework.eventhandling.GlobalSequenceTrackingToken"
}