Links And Field Mappings

中文：Link 与字段映射

Links turn independent model definitions into an object graph. Field mappings explain how one side of a link matches another side.

Link Kinds

Kind	Source	Destination	Purpose
data_link	EntitySet	DataSet	Shows which telemetry belongs to which object type.
entity_set_link	EntitySet	EntitySet	Defines topology relation semantics between object types.
storage_link	DataSet	Storage	Routes datasets to physical storage.
runbook_link	EntitySet	RunbookSet	Attaches operational guidance to an object type.

DataLink

DataLink maps entity fields to dataset labels or fields.

kind: data_link
metadata:
  name: "devops.service_related_to_devops.metric.devops.service"
  domain: devops
spec:
  src:
    domain: devops
    kind: entity_set
    name: devops.service
  dest:
    domain: devops
    kind: metric_set
    name: devops.metric.devops.service
  data_link_type: related_to
  fields_mapping:
    "service_id": "service_id"

Query-time meaning: from a devops.service entity, entity field service_id matches metric label service_id.

EntitySetLink

EntitySetLink defines topology relation types such as:

• contains
• calls
• instance_of
• parent_of
• same_as

The link defines what a relation means. Runtime relation records provide the actual edges.

StorageLink

StorageLink keeps physical storage separate from dataset semantics.

kind: storage_link
metadata:
  name: "devops.storage_link.devops.metric.devops.service"
  domain: devops
spec:
  src:
    domain: devops
    kind: metric_set
    name: devops.metric.devops.service
  dest:
    domain: devops
    kind: sls_metricstore
    name: devops.metric_set.core.storage

Field Mapping Rules

Use mappings when a value has different names in different systems:

Source field	Destination field	Example
Entity field	Dataset label	service_id -> acs_arms_service_id
Source entity field	Relation metric label	${{src.service_id}} -> acs_arms_p_service_id
Destination entity field	Relation metric label	${{dest.service_id}} -> acs_arms_service_id

Design Rules

• Keep links small and explicit.
• Prefer stable IDs over display names.
• Put conditional availability in link-level filters when needed.
• Name links so source, relation type, and destination are obvious.
• Test links with a sample entity and a query plan before documenting them as supported.

Related Concepts

• Entity Sets
• Datasets
• Storage And GraphStore Providers