@startuml

skinparam backgroundColor transparent

package "PostgREST" {
  () HTTP as HTTPAPI
  HTTPAPI  - [Auth]
  [Auth] -r.> [ApiRequest]
  [ApiRequest] -r.> [Plan]
  [Plan] -r.> [Query]
  [Query] - () "Connection Pool" : "\t"
  [Plan] -u-> [Schema Cache]:uses
  [Schema Cache] <- () Listener : reloads

  () HTTP as HTTPADMIN
  [Admin]  -r- () HTTPADMIN
  [Config] -l- () CLI

  [Config] <-r~ Listener

  HTTPADMIN -[hidden]r- CLI
  [Schema Cache] -l[hidden]- [Config]
  [Schema Cache] -l[hidden]- [Admin]
  [Schema Cache] -l[hidden]- CLI
}


database "PostgreSQL" {
  node Authorization {
    rectangle "Roles, GRANT, RLS"
  }
  node "API schema" as API {
    rectangle "Functions, Views"
  }
  rectangle "Tables, extensions" as tbs
  API -d- tbs

  API -l[hidden]- Authorization
}

:user:
hexagon Proxy
:user: .r-> Proxy : request with JWT
HTTPAPI <.l- Proxy

hexagon ExternalAuth
ExternalAuth -u[hidden]- Proxy
:user: .r-> ExternalAuth : login
:user: <.r- ExternalAuth : JWT

:operator: .d-> HTTPADMIN
:operator: .d-> CLI


PostgreSQL <.developer : "\t"
Listener -r.> "PostgreSQL"
"Connection Pool" -r.> "PostgreSQL" : "\t\t"

note bottom of Auth
  Validates the JWT
end note

note bottom of ApiRequest
  Parses the URL syntax
end note

note bottom of Plan
  Generates internal AST
end note

note bottom of Query
  Generates the SQL
end note

note top of Listener
  LISTEN session
end note

url of ExternalAuth is [[../explanations/external_auth.html]]
url of Admin is [[../references/admin_server.html#admin-server]]
url of API is [[../explanations/schema_isolation.html]]
url of Auth is [[../references/auth.html#authn]]
url of ApiRequest is [[../explanations/architecture.html#api-request]]
url of Plan is [[../explanations/architecture.html#plan]]
url of Query is [[../explanations/architecture.html#query]]
url of Authorization is [[../explanations/db_authz.html]]
url of CLI is [[../references/cli.html#cli]]
url of "Connection Pool" is [[../references/connection_pool.html]]
url of Config is [[../references/configuration.html#configuration]]
url of HTTPADMIN is [[../explanations/architecture.html#http]]
url of HTTPAPI is [[../explanations/architecture.html#http]]
url of Listener is [[../references/listener.html#listener]]
url of Proxy is [[../explanations/nginx.html]]
url of "Schema Cache" is [[../references/schema_cache.html#schema-cache]]

@enduml