Added basic readiness check for registry API

CHANGES.md

@@ -12,6 +12,7 @@
 -   Fixed: some helm chart (gateway & web) deployment doesn't allow setting `replicas` value properly
 -   Added an opt-in for chart/map/table previews if files are large.
 -   Upgraded helm-docs to v1.2.1
+-   Added basic readiness check for registry API
 
 ## 0.0.57
 

magda-registry-api/src/main/scala/au/csiro/data61/magda/registry/Api.scala

@@ -133,10 +133,18 @@ class Api(
 
   val routes = handleExceptions(myExceptionHandler) {
     pathPrefix("v0") {
-      path("ping") { complete("OK") } ~
+      path("ping") {
+        complete("OK")
+      } ~
         pathPrefix("status") {
-          path("live") { complete("OK") } ~
-            path("ready") { complete(ReadyStatus(true)) }
+          new ProbesService(
+            config,
+            authApiClient,
+            system,
+            materializer,
+            recordPersistence,
+            eventPersistence
+          ).route
         } ~ roleDependentRoutes
     }
   }

magda-registry-api/src/main/scala/au/csiro/data61/magda/registry/ProbesService.scala

@@ -0,0 +1,62 @@
+package au.csiro.data61.magda.registry
+
+import java.util.concurrent.TimeoutException
+
+import akka.actor.{ActorRef, ActorSystem}
+import akka.event.Logging
+import akka.http.scaladsl.model.StatusCodes
+import akka.http.scaladsl.server.Directives._
+import akka.http.scaladsl.server.Route
+import akka.stream.Materializer
+import au.csiro.data61.magda.client.AuthApiClient
+import au.csiro.data61.magda.directives.AuthDirectives.requireIsAdmin
+import au.csiro.data61.magda.directives.TenantDirectives.{
+  requiresTenantId,
+  requiresSpecifiedTenantId
+}
+import au.csiro.data61.magda.model.Registry._
+import com.typesafe.config.Config
+import gnieh.diffson.sprayJson._
+import io.swagger.annotations._
+import javax.ws.rs.Path
+import scalikejdbc.DB
+import org.everit.json.schema.ValidationException
+
+import scala.concurrent.{Await, ExecutionContext, Future}
+import scala.concurrent.duration._
+import scala.util.{Failure, Success}
+
+// @Path("/status")
+class ProbesService(
+    config: Config,
+    authClient: RegistryAuthApiClient,
+    system: ActorSystem,
+    materializer: Materializer,
+    recordPersistence: RecordPersistence,
+    eventPersistence: EventPersistence
+) extends Protocols {
+  val logger = Logging(system, getClass)
+  implicit val ec: ExecutionContext = system.dispatcher
+
+  def live: Route = get {
+    path("live") {
+      complete("OK")
+    }
+  }
+
+  def ready: Route = get {
+    path("ready") {
+      DB readOnly { session =>
+        recordPersistence.getReadiness(Some(logger))(session)
+      } match {
+        case Some(true) => complete("OK")
+        case Some(false) | None =>
+          complete(StatusCodes.InternalServerError, "Database not ready")
+      }
+    }
+  }
+
+  val route =
+    live ~
+      ready
+}

magda-registry-api/src/main/scala/au/csiro/data61/magda/registry/RecordPersistence.scala

@@ -63,6 +63,10 @@ trait RecordPersistence {
       aspectOrQueries: Iterable[AspectQuery] = Nil
   )(implicit session: DBSession): Long
 
+  def getReadiness(
+      logger: Option[LoggingAdapter] = None
+  )(implicit session: DBSession): Option[Boolean]
+
   def getById(
       tenantId: TenantId,
       opaQueries: Option[List[(String, List[List[OpaQuery]])]],
@@ -245,6 +249,7 @@ class DefaultRecordPersistence(config: Config)
 
   /**
     * Given a list of recordIds, filter out any record that the current user has not access and return the rest of ids
+    *
     * @param tenantId
     * @param opaRecordQueries
     * @param recordIds
@@ -323,6 +328,51 @@ class DefaultRecordPersistence(config: Config)
     }
   }
 
+  def getReadiness(
+      logger: Option[LoggingAdapter] = None
+  )(implicit session: DBSession): Option[Boolean] = {
+    def checkTableExists(table: String): Boolean = {
+      try {
+        val schemaAndTable = "public." + table
+        val regclass = sql"select to_regclass(${schemaAndTable})"
+
+        val tableExists = regclass
+          .map(_.toMap)
+          .list
+          .apply()
+          .map { res =>
+            {
+              res("to_regclass").toString == table
+            }
+          }
+          .forall(x => x);
+        tableExists
+      } catch {
+        case e: Exception => {
+          if (logger.isDefined) {
+            logger.get.error(
+              e,
+              s"Error occurred on getReadiness probe for table ${table}"
+            )
+          }
+          false
+        }
+      }
+    }
+
+    Some(
+      List(
+        checkTableExists("aspects"),
+        checkTableExists("events"),
+        checkTableExists("eventtypes"),
+        checkTableExists("recordaspects"),
+        checkTableExists("records"),
+        checkTableExists("webhookevents"),
+        checkTableExists("webhooks")
+      ).forall(x => x)
+    )
+  }
+
   def getAllWithAspects(
       tenantId: TenantId,
       aspectIds: Iterable[String],
@@ -676,7 +726,9 @@ where (RecordAspects.recordId, RecordAspects.aspectId)=($recordId, $aspectId) AN
         case _                           => Success(result)
       }
       // No failed aspects, so unwrap the aspects from the Success Trys.
-      resultAspects <- Try { patchedAspects.mapValues(_.get) }
+      resultAspects <- Try {
+        patchedAspects.mapValues(_.get)
+      }
     } yield
       result.copy(aspects = resultAspects, sourceTag = newRecord.sourceTag)
   }
@@ -1368,7 +1420,7 @@ where (RecordAspects.recordId, RecordAspects.aspectId)=($recordId, $aspectId) AN
       aspectIds: Iterable[String] = List()
   )(implicit session: DBSession): Try[Iterable[String]] = {
 
-    /** For aspects that have links to other aspects, a map of the ids of those aspects to the location (first-level, not path) in their JSON where the link is  */
+    /** For aspects that have links to other aspects, a map of the ids of those aspects to the location (first-level, not path) in their JSON where the link is */
     val referenceMap = this.buildReferenceMap(aspectIds)
 
     Try {
@@ -1952,6 +2004,7 @@ where (RecordAspects.recordId, RecordAspects.aspectId)=($recordId, $aspectId) AN
       case _            => throw new Exception("Invalid tenant value " + tenantId)
     }
   }
+
   private def aspectIdsToWhereClause(
       tenantId: TenantId,
       aspectIds: Iterable[String]