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Scope tree

do.ExplainInjector prints the full tree of scopes attached to an injector — every child scope, the services registered in each one, their loading type (lazy, eager, transient), and whether they implement Healthchecker or Shutdowner. Use it to debug an unexpected dependency resolution or to understand an unfamiliar codebase's module layout.

Spec​

do.ExplainInjector(do.Injector) do.ExplainInjectorOutput

Play: https://go.dev/play/p/mRs4Q7TJ5jj

debug := do.ExplainInjector(scope)
println(debug.String())

Output:

Scope ID: 35d18a30-0cb9-4fad-aa3c-1438937612ad
Scope name: [root]

DAG:
 |
  \_ [root] (ID: 35d18a30-0cb9-4fad-aa3c-1438937612ad)
      * 😴 PostgreSQLClientService 🫀 🙅
      * 😴 RedisClientService 🫀 🙅
      * 🔁 Config
      * 🔗 Logger
      |
      |
      |\_ api (ID: dce6f365-fc52-4407-ac02-a6a857e0cbc9)
      |    |
      |    |
      |    |\_ public-api (ID: b9cac0c2-da74-4ee1-a5e0-eb30dca912c3)
      |    |    * 😴 PublicApiRouterService
      |    |    |
      |    |    |
      |    |    |\_ public-api-v1 (ID: a4407628-5b3e-4abf-8d6d-82557d5ddb13)
      |    |    |    * 😴 UserControllerService
      |    |    |
      |    |    |
      |    |     \_ public-api-v2 (ID: adc75f0a-a2dc-488f-9457-510e151d9e34)
      |    |         * 😴 UserControllerService
      |    |         * 😴 ProductControllerService
      |    |         * 😴 CartControllerService
      |    |
      |    |
      |     \_ internal-api (ID: a9e3adfc-ad10-4cbd-9b0d-85cfad95d99c)
      |         * 😴 InternalApiRouterService
      |         * 😴 UserManagementControllerService
      |
      |
       \_ jobs (ID: 53406825-b7cc-46cc-9baf-ab0319c8a3bd)
           * 😴 StatisticsJobService
           * 😴 RateLimitResetJobService

Emojis describe service type:

  • 😴 Lazy service
  • 🔁 Eager service
  • 🏭 Transient service
  • 🔗 Service alias

...and capabilities:

  • 🫀 Implements Healthchecker
  • 🙅 Implements Shutdowner