Adding support to bind multiple listeners to backfill run events

service/src/main/kotlin/app/cash/backfila/dashboard/BackfillStateToggler.kt

@@ -1,5 +1,6 @@
 package app.cash.backfila.dashboard
 
+import app.cash.backfila.service.BackfillRunListener
 import app.cash.backfila.service.SlackHelper
 import app.cash.backfila.service.persistence.BackfilaDb
 import app.cash.backfila.service.persistence.BackfillState
@@ -19,7 +20,7 @@ import wisp.logging.getLogger
 class BackfillStateToggler @Inject constructor(
   @BackfilaDb private val transacter: Transacter,
   private val queryFactory: Query.Factory,
-  private val slackHelper: SlackHelper,
+  private val backfillRunListeners: Set<BackfillRunListener>,
 ) {
   fun toggleRunningState(id: Long, caller: MiskCaller, desiredState: BackfillState) {
     val requiredCurrentState = when (desiredState) {
@@ -59,9 +60,13 @@ class BackfillStateToggler @Inject constructor(
     }
 
     if (desiredState == RUNNING) {
-      slackHelper.runStarted(Id(id), caller.principal)
+      for (listener in backfillRunListeners) {
+        listener.runStarted(Id(id), caller.principal)
+      }
     } else {
-      slackHelper.runPaused(Id(id), caller.principal)
+      for (listener in backfillRunListeners) {
+        listener.runPaused(Id(id), caller.principal)
+      }
     }
   }
 

service/src/main/kotlin/app/cash/backfila/service/BackfilaServiceModule.kt

@@ -65,6 +65,10 @@ class BackfilaServiceModule(
       install(SlackModule(config.slack))
     }
 
+    newMultibinder<BackfillRunListener>()
+            .addBinding()
+            .to(SlackHelper::class)
+
     // TODO:mikepaw Require that the Admin Console is installed so it isn't forgotten.
     // something along the lines of requireBinding but works for multibindings.
   }

service/src/main/kotlin/app/cash/backfila/service/BackfillRunListener.kt

@@ -0,0 +1,12 @@
+package app.cash.backfila.service
+
+import app.cash.backfila.service.persistence.DbBackfillRun
+import misk.hibernate.Id
+import misk.hibernate.load
+
+interface BackfillRunListener {
+    fun runStarted(id: Id<DbBackfillRun>, user: String)
+    fun runPaused(id: Id<DbBackfillRun>, user: String)
+    fun runErrored(id: Id<DbBackfillRun>)
+    fun runCompleted(id: Id<DbBackfillRun>)
+}

service/src/main/kotlin/app/cash/backfila/service/SlackHelper.kt

@@ -14,8 +14,8 @@ class SlackHelper @Inject constructor(
   private val slackClient: SlackClient,
   private val backfilaConfig: BackfilaConfig,
   private val deployment: Deployment,
-) {
-  fun runStarted(id: Id<DbBackfillRun>, user: String) {
+) : BackfillRunListener {
+  override fun runStarted(id: Id<DbBackfillRun>, user: String) {
     val (message, channel) = transacter.transaction { session ->
       val run = session.load(id)
       val message = ":backfila_start:${dryRunEmoji(run)} ${nameAndId(run)} started by @$user"
@@ -24,7 +24,7 @@ class SlackHelper @Inject constructor(
     slackClient.postMessage("Backfila", ":backfila:", message, channel)
   }
 
-  fun runPaused(id: Id<DbBackfillRun>, user: String) {
+  override fun runPaused(id: Id<DbBackfillRun>, user: String) {
     val (message, channel) = transacter.transaction { session ->
       val run = session.load(id)
       val message = ":backfila_pause:${dryRunEmoji(run)} ${nameAndId(run)} paused by @$user"
@@ -33,7 +33,7 @@ class SlackHelper @Inject constructor(
     slackClient.postMessage("Backfila", ":backfila:", message, channel)
   }
 
-  fun runErrored(id: Id<DbBackfillRun>) {
+  override fun runErrored(id: Id<DbBackfillRun>) {
     val (message, channel) = transacter.transaction { session ->
       val run = session.load(id)
       val message = ":backfila_error:${dryRunEmoji(run)} ${nameAndId(run)} paused due to error"
@@ -42,7 +42,7 @@ class SlackHelper @Inject constructor(
     slackClient.postMessage("Backfila", ":backfila:", message, channel)
   }
 
-  fun runCompleted(id: Id<DbBackfillRun>) {
+  override fun runCompleted(id: Id<DbBackfillRun>) {
     val (message, channel) = transacter.transaction { session ->
       val run = session.load(id)
       val message = ":backfila_complete:${dryRunEmoji(run)} ${nameAndId(run)} completed"

service/src/main/kotlin/app/cash/backfila/service/runner/BackfillRunner.kt

@@ -8,7 +8,7 @@ import app.cash.backfila.protos.clientservice.RunBatchRequest
 import app.cash.backfila.protos.clientservice.RunBatchResponse
 import app.cash.backfila.service.BackfilaConfig
 import app.cash.backfila.service.BackfilaMetrics
-import app.cash.backfila.service.SlackHelper
+import app.cash.backfila.service.BackfillRunListener
 import app.cash.backfila.service.persistence.BackfilaDb
 import app.cash.backfila.service.persistence.BackfillState
 import app.cash.backfila.service.persistence.DbBackfillRun
@@ -281,7 +281,9 @@ class BackfillRunner private constructor(
           "Paused backfill ${logLabel()} due to too many consecutive failures: $failuresSinceSuccess"
         }
 
-        factory.slackHelper.runErrored(backfillRunId)
+        for (listener in factory.backfillRunListeners) {
+          listener.runErrored(backfillRunId)
+        }
 
         recordErrorEvent(exception, action, elapsed, backoffMs = null, paused = true)
       }
@@ -410,7 +412,7 @@ class BackfillRunner private constructor(
     val clock: Clock,
     val queryFactory: Query.Factory,
     val connectorProvider: ConnectorProvider,
-    val slackHelper: SlackHelper,
+    val backfillRunListeners: Set<BackfillRunListener>,
     val loggingSetupProvider: BackfillRunnerLoggingSetupProvider,
     val metrics: BackfilaMetrics,
     val backfilaConfig: BackfilaConfig,

service/src/main/kotlin/app/cash/backfila/service/runner/statemachine/BatchAwaiter.kt

@@ -208,7 +208,9 @@ class BatchAwaiter(
     }
 
     if (runComplete) {
-      backfillRunner.factory.slackHelper.runCompleted(backfillRunner.backfillRunId)
+      for (listener in backfillRunner.factory.backfillRunListeners) {
+        listener.runCompleted(backfillRunner.backfillRunId)
+      }
     }
   }