...
Only once this done should we be able to trigger migrate.
Assumptions:
- We assume that composition target is already primed
- Participants execute the effective pre-check.
- Pre-check is completely optional. it will be
- Only the participants can execute a effective precheck.
- Precheck is executed before the migration, if . If it fail or the migration is not supported, can the migration will be not executed.?
- User needs to receive receives the result of the precheck .Acm-runtime needs to handle the precheck fail in a different way it handles migration failon the outProperties result.
Solution: create a new flow for migration-precheck
...
- User send migration-precheck action
- Acm-runtime set the state of the instance in "MIGRATING-PRECHECK" deployState
- Acm-runtime sends migration-precheck message to participants (it will be AUTOMATION_COMPOSITION_MIGRATION message with Boolean flag "precheck" set to true)
- Participant receives migration-precheck message and executes the precheck and sends the result (it will be a new method "migratePrecheck()" that participant has to implement)
- It will add a new NOT_VALID state in stateChangeResult
- Acm-runtime receives precheck-result messages from all participants
- Acm-runtime shows this result into the stateChangeResult
- NO_ERROR: means the migration is supported (deployState will be in "DEPLOYED")NOT_VALID: means the migration is not supported (deployState will be in "DEPLOYED"state will back as before the precheck-migration call)
- FAILED: means something went wrong during the migration precheck (deployState state will be in "MIGRATING-PRECHECK")
- It will be implemented migratePrecheck() in participant-simulator to test all scenarios.
PlantUML Macro |
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@startuml participant "ACM Runtime" participant Participant participant AutomationCompositionElementListener alt "Priming Compositon Target"instance Id"ACM andRuntime" Composition-> Ids"ACM exist"Runtime" : Create Compositon Target "ACM Runtime" -> Participant : [ASYNC] Migration pre-check message Prime Compositon Target Participant -> AutomationCompositionElementListener : Prime Compositon Target AutomationCompositionElementListener -> Participant : Compositon Target primed Participant -> "ACM Runtime" : [ASYNC] Compositon Target primed end alt "Migrating pre-check an instance to Compositon Target" "ACM Runtime" -> Participant : [ASYNC] Message for migration pre-check from source to target composition Participant -> AutomationCompositionElementListener : Migrate pre-check AC Element AutomationCompositionElementListener -> Participant : Migrate supported / not supported Participant -> "ACM Runtime" : [ASYNC] Migration pre-check completed note right Returns AUTOMATION_COMPOSITION_STATE_CHANGE message. end note end alt "Migrating an instance to Compositon Target" "ACM Runtime" -> Participant : [ASYNC] Message for migration from source to target composition Participant -> AutomationCompositionElementListener : Migrate AC Element AutomationCompositionElementListener -> Participant : Element instance Migrated Participant -> "ACM Runtime" : [ASYNC] Migration completed note right Returns AUTOMATION_COMPOSITION_STATE_CHANGE message. end note end @enduml |
Allowed operations
stateChangeResult | deployStatestate | Allowed | Not Allowed Operation |
---|---|---|---|
NOT_VALID | DEPLOYED | UPDATE, UNDEPLOY, UNLOCK, MIGRATE_PRECHECK | DELETE, DEPLOY, MIGRATE, LOCK |
FAILED | MIGRATING-PRECHECK | UNDEPLOY, MIGRATE_PRECHECK | UPDATE, DELETE, DEPLOY, MIGRATE, UNLOCK, LOCK |
TIMEOUT | MIGRATING-PRECHECK | UNDEPLOY, MIGRATE_PRECHECK | UPDATE, DELETE, DEPLOY, MIGRATE, UNLOCK, LOCK |
...
Code Block | ||
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| ||
name: DemoInstance0
version: 1.0.1
compositionId: {{composition1Id}}
instanceId: {{instanceId}}
compositionTargetId: {{composition2Id}}
precheck: true
....................... |
What state suits for migration-precheck?
Differently in what happen in deploy, undeploy, update and migrate, the migration-precheck operation do not make changes in the applications (same will be for prepare and review). What state is most suitable for that operation?
Using deployState, lockState or a new subState does not impact the migration-precheck functionality, it is an implementation detail that it help to understand how to implement all new functionalities.