Add a command to list the triggers in a DAR (#3268)

For now, this uses a somewhat adhoc format with one trigger identifier
per line but given that I expect that it won’t be particularly common
to want to do this mechanically this should be sufficient and it’s
trivial to parse.

triggers/runner/src/main/scala/com/daml/trigger/RunnerConfig.scala

@@ -10,6 +10,8 @@ import com.digitalasset.platform.services.time.TimeProviderType
 
 case class RunnerConfig(
     darPath: File,
+    // If true, we will only list the triggers in the DAR and exit.
+    listTriggers: Boolean,
     triggerIdentifier: String,
     ledgerHost: String,
     ledgerPort: Int,
@@ -28,22 +30,18 @@ object RunnerConfig {
       .text("Path to the dar file containing the trigger")
 
     opt[String]("trigger-name")
-      .required()
       .action((t, c) => c.copy(triggerIdentifier = t))
       .text("Identifier of the trigger that should be run in the format Module.Name:Entity.Name")
 
     opt[String]("ledger-host")
-      .required()
       .action((t, c) => c.copy(ledgerHost = t))
       .text("Ledger hostname")
 
     opt[Int]("ledger-port")
-      .required()
       .action((t, c) => c.copy(ledgerPort = t))
       .text("Ledger port")
 
     opt[String]("ledger-party")
-      .required()
       .action((t, c) => c.copy(ledgerParty = t))
       .text("Ledger party")
 
@@ -58,16 +56,41 @@ object RunnerConfig {
         c.copy(commandTtl = Duration.ofSeconds(t))
       }
       .text("TTL in seconds used for commands emitted by the trigger. Defaults to 30s.")
+
+    cmd("list")
+      .action((_, c) => c.copy(listTriggers = true))
+      .text("List the triggers in the DAR.")
+
+    checkConfig(c =>
+      if (c.listTriggers) {
+        // I do not want to break the trigger CLI and require a
+        // "run" command so I can’t make these options required
+        // in general. Therefore, we do this check in checkConfig.
+        success
+      } else {
+        if (c.triggerIdentifier == null) {
+          failure("Missing option --trigger-name")
+        } else if (c.ledgerHost == null) {
+          failure("Missing option --ledger-host")
+        } else if (c.ledgerPort == 0) {
+          failure("Missing option --ledger-port")
+        } else if (c.ledgerParty == null) {
+          failure("Missing option --ledger-pary")
+        } else {
+          success
+        }
+    })
   }
   def parse(args: Array[String]): Option[RunnerConfig] =
     parser.parse(
       args,
       RunnerConfig(
         darPath = null,
+        listTriggers = false,
         triggerIdentifier = null,
-        ledgerHost = "",
+        ledgerHost = null,
         ledgerPort = 0,
-        ledgerParty = "",
+        ledgerParty = null,
         timeProviderType = TimeProviderType.Static,
         commandTtl = Duration.ofSeconds(30L),
       )

triggers/runner/src/main/scala/com/daml/trigger/RunnerMain.scala

@@ -5,6 +5,7 @@ package com.daml.trigger
 
 import akka.actor.ActorSystem
 import akka.stream._
+import java.io.File
 import scala.concurrent.{Await, ExecutionContext, Future}
 import scala.concurrent.duration.Duration
 import scalaz.syntax.traverse._
@@ -12,7 +13,7 @@ import scalaz.syntax.traverse._
 import com.digitalasset.daml.lf.archive.{Dar, DarReader}
 import com.digitalasset.daml.lf.archive.Decode
 import com.digitalasset.daml.lf.data.Ref.{Identifier, PackageId, QualifiedName}
-import com.digitalasset.daml.lf.language.Ast.Package
+import com.digitalasset.daml.lf.language.Ast._
 import com.digitalasset.daml_lf_dev.DamlLf
 import com.digitalasset.grpc.adapter.AkkaExecutionSequencerPool
 import com.digitalasset.ledger.api.refinements.ApiTypes.ApplicationId
@@ -25,6 +26,24 @@ import com.digitalasset.ledger.client.configuration.{
 
 object RunnerMain {
 
+  def listTriggers(darPath: File, dar: Dar[(PackageId, Package)]) = {
+    val triggerIds = TriggerIds.fromDar(dar)
+    println(s"Listing triggers in $darPath:")
+    for ((modName, mod) <- dar.main._2.modules) {
+      for ((defName, defVal) <- mod.definitions) {
+        defVal match {
+          case DValue(TApp(TTyCon(tcon), _), _, _, _) => {
+            if (tcon == triggerIds.getHighlevelId("Trigger")
+              || tcon == triggerIds.getId("Trigger")) {
+              println(s"  $modName:$defName")
+            }
+          }
+          case _ => {}
+        }
+      }
+    }
+  }
+
   def main(args: Array[String]): Unit = {
 
     RunnerConfig.parse(args) match {
@@ -36,6 +55,11 @@ object RunnerMain {
           case (pkgId, pkgArchive) => Decode.readArchivePayload(pkgId, pkgArchive)
         }
 
+        if (config.listTriggers) {
+          listTriggers(config.darPath, dar)
+          sys.exit(0)
+        }
+
         val triggerId: Identifier =
           Identifier(dar.main._1, QualifiedName.assertFromString(config.triggerIdentifier))
 

triggers/tests/BUILD.bazel

@@ -88,3 +88,19 @@ client_server_test(
     ],
     server_files = ["$(rootpath :acs.dar)"],
 )
+
+sh_test(
+    name = "list-triggers",
+    srcs = ["list-triggers.sh"],
+    args = [
+        "$(location //triggers/runner:trigger-runner)",
+        "$(location :acs.dar)",
+    ],
+    data = [
+        ":acs.dar",
+        "//triggers/runner:trigger-runner",
+    ],
+    deps = [
+        "@bazel_tools//tools/bash/runfiles",
+    ],
+)

triggers/tests/list-triggers.sh

@@ -0,0 +1,44 @@
+# Copyright (c) 2019 The DAML Authors. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+set -eou pipefail
+
+# --- begin runfiles.bash initialization ---
+# Copy-pasted from Bazel's Bash runfiles library (tools/bash/runfiles/runfiles.bash).
+if [[ ! -d "${RUNFILES_DIR:-/dev/null}" && ! -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
+  if [[ -f "$0.runfiles_manifest" ]]; then
+    export RUNFILES_MANIFEST_FILE="$0.runfiles_manifest"
+  elif [[ -f "$0.runfiles/MANIFEST" ]]; then
+    export RUNFILES_MANIFEST_FILE="$0.runfiles/MANIFEST"
+  elif [[ -f "$0.runfiles/bazel_tools/tools/bash/runfiles/runfiles.bash" ]]; then
+    export RUNFILES_DIR="$0.runfiles"
+  fi
+fi
+if [[ -f "${RUNFILES_DIR:-/dev/null}/bazel_tools/tools/bash/runfiles/runfiles.bash" ]]; then
+  source "${RUNFILES_DIR}/bazel_tools/tools/bash/runfiles/runfiles.bash"
+elif [[ -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
+  source "$(grep -m1 "^bazel_tools/tools/bash/runfiles/runfiles.bash " \
+            "$RUNFILES_MANIFEST_FILE" | cut -d ' ' -f 2-)"
+else
+  echo >&2 "ERROR: cannot find @bazel_tools//tools/bash/runfiles:runfiles.bash"
+  exit 1
+fi
+# --- end runfiles.bash initialization ---
+
+TRIGGER_EXE=$(rlocation "$TEST_WORKSPACE/$1")
+DAR=$(rlocation "$TEST_WORKSPACE/$2")
+OUTPUT="$($TRIGGER_EXE list --dar $DAR | tail -n '+2' | tr -d '\r')"
+EXPECTED="\
+  Retry:retryTrigger
+  ACS:test
+  CopyTrigger:copyTrigger\
+"
+
+if [ "$OUTPUT" != "$EXPECTED" ]; then
+    echo "Unexpected output:"
+    echo "$OUTPUT"
+    echo "Expected:"
+    echo "$EXPECTED"
+    exit 1
+fi
+