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Posted to commits@kafka.apache.org by cm...@apache.org on 2019/06/06 17:04:22 UTC
[kafka] branch trunk updated: MINOR: Improve Trogdor external
command worker docs (#6438)
This is an automated email from the ASF dual-hosted git repository.
cmccabe pushed a commit to branch trunk
in repository https://gitbox.apache.org/repos/asf/kafka.git
The following commit(s) were added to refs/heads/trunk by this push:
new 58aa04f MINOR: Improve Trogdor external command worker docs (#6438)
58aa04f is described below
commit 58aa04f91e9cd8203cd58f972d042d068727d256
Author: Stanislav Kozlovski <fa...@windowslive.com>
AuthorDate: Thu Jun 6 20:04:05 2019 +0300
MINOR: Improve Trogdor external command worker docs (#6438)
Reviewers: Colin McCabe <cm...@apache.org>, Xi Yang <xi...@confluent.io>
---
TROGDOR.md | 23 +++++++++++++++++++++-
tests/bin/external_trogdor_command_example.py | 13 +++++++-----
.../trogdor/workload/ExternalCommandWorker.java | 2 +-
.../workload/ExternalCommandWorkerTest.java | 10 ++--------
4 files changed, 33 insertions(+), 15 deletions(-)
diff --git a/TROGDOR.md b/TROGDOR.md
index 49c6942..ad8d8af 100644
--- a/TROGDOR.md
+++ b/TROGDOR.md
@@ -16,7 +16,7 @@ Running Kafka:
> ./bin/kafka-server-start.sh ./config/server.properties &> /tmp/kafka.log &
-Then, we want to run a Trogdor Agent, plus a Trogdor broker.
+Then, we want to run a Trogdor Agent, plus a Trogdor Coordinator.
To run the Trogdor Agent:
@@ -125,6 +125,27 @@ ProcessStopFault stops a process by sending it a SIGSTOP signal. When the fault
### NetworkPartitionFault
NetworkPartitionFault sets up an artificial network partition between one or more sets of nodes. Currently, this is implemented using iptables. The iptables rules are set up on the outbound traffic from the affected nodes. Therefore, the affected nodes should still be reachable from outside the cluster.
+External Processes
+========================================
+Trogdor supports running arbitrary commands in external processes. This is a generic way to run any configurable command in the Trogdor framework - be it a Python program, bash script, docker image, etc.
+
+### ExternalCommandWorker
+ExternalCommandWorker starts an external command defined by the ExternalCommandSpec. It essentially allows you to run any command on any Trogdor agent node.
+The worker communicates with the external process via its stdin, stdout and stderr in a JSON protocol. It uses stdout for any actionable communication and only logs what it sees in stderr.
+On startup the worker will first send a message describing the workload to the external process in this format:
+```
+{"id":<task ID string>, "workload":<configured workload JSON object>}
+```
+and will then listen for messages from the external process, again in a JSON format.
+Said JSON can contain the following fields:
+- status: If the object contains this field, the status of the worker will be set to the given value.
+- error: If the object contains this field, the error of the worker will be set to the given value. Once an error occurs, the external process will be terminated.
+- log: If the object contains this field, a log message will be issued with this text.
+An example:
+```json
+{"log": "Finished successfully.", "status": {"p99ProduceLatency": "100ms", "messagesSent": 10000}}
+```
+
Exec Mode
========================================
Sometimes, you just want to run a test quickly on a single node. In this case, you can use "exec mode." This mode allows you to run a single Trogdor Agent without a Coordinator.
diff --git a/tests/bin/external_trogdor_command_example.py b/tests/bin/external_trogdor_command_example.py
index 0e53557..1254b82 100755
--- a/tests/bin/external_trogdor_command_example.py
+++ b/tests/bin/external_trogdor_command_example.py
@@ -20,7 +20,7 @@ import time
#
# This is an example of an external script which can be run through Trogdor's
-# ExternalCommandWorker.
+# ExternalCommandWorker. It sleeps for the given amount of time expressed by the delayMs field in the ExternalCommandSpec
#
if __name__ == '__main__':
@@ -28,11 +28,14 @@ if __name__ == '__main__':
line = sys.stdin.readline()
start_message = json.loads(line)
workload = start_message["workload"]
- print("Starting external_trogdor_command_example with task id %s, workload %s" \
- % (start_message["id"], workload))
+ print("Starting external_trogdor_command_example with task id %s, workload %s"
+ % (start_message["id"], workload))
sys.stdout.flush()
- `print(json.dumps({"status": "running"}))`
+
+ # pretend to start some workload
+ print(json.dumps({"status": "running"}))
sys.stdout.flush()
time.sleep(0.001 * workload["delayMs"])
- `print(json.dumps({"status": "exiting after %s delayMs" % workload["delayMs"]}))`
+
+ print(json.dumps({"status": "exiting after %s delayMs" % workload["delayMs"]}))
sys.stdout.flush()
diff --git a/tools/src/main/java/org/apache/kafka/trogdor/workload/ExternalCommandWorker.java b/tools/src/main/java/org/apache/kafka/trogdor/workload/ExternalCommandWorker.java
index 6f5799f..9db7f18 100644
--- a/tools/src/main/java/org/apache/kafka/trogdor/workload/ExternalCommandWorker.java
+++ b/tools/src/main/java/org/apache/kafka/trogdor/workload/ExternalCommandWorker.java
@@ -389,7 +389,7 @@ public class ExternalCommandWorker implements TaskWorker {
spec.shutdownGracePeriodMs().get() : DEFAULT_SHUTDOWN_GRACE_PERIOD_MS;
if (!executor.awaitTermination(shutdownGracePeriodMs, TimeUnit.MILLISECONDS)) {
terminatorActionQueue.add(TerminatorAction.DESTROY_FORCIBLY);
- executor.awaitTermination(1000, TimeUnit.DAYS);
+ executor.awaitTermination(1, TimeUnit.DAYS);
}
this.status = null;
this.doneFuture = null;
diff --git a/tools/src/test/java/org/apache/kafka/trogdor/workload/ExternalCommandWorkerTest.java b/tools/src/test/java/org/apache/kafka/trogdor/workload/ExternalCommandWorkerTest.java
index 9800b13..73ac77c 100644
--- a/tools/src/test/java/org/apache/kafka/trogdor/workload/ExternalCommandWorkerTest.java
+++ b/tools/src/test/java/org/apache/kafka/trogdor/workload/ExternalCommandWorkerTest.java
@@ -17,7 +17,6 @@
package org.apache.kafka.trogdor.workload;
-import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.IntNode;
import com.fasterxml.jackson.databind.node.JsonNodeFactory;
import com.fasterxml.jackson.databind.node.ObjectNode;
@@ -109,7 +108,7 @@ public class ExternalCommandWorkerTest {
}
/**
- * Test attempting to run an exeutable which doesn't exist.
+ * Test attempting to run an executable which doesn't exist.
* We use a path which starts with /dev/null, since that should never be a
* directory in UNIX.
*/
@@ -172,12 +171,7 @@ public class ExternalCommandWorkerTest {
}
}
CompletableFuture<String> statusFuture = new CompletableFuture<>();
- final WorkerStatusTracker statusTracker = new WorkerStatusTracker() {
- @Override
- public void update(JsonNode status) {
- statusFuture .complete(status.textValue().toString());
- }
- };
+ final WorkerStatusTracker statusTracker = status -> statusFuture .complete(status.textValue());
ExternalCommandWorker worker = new ExternalCommandWorkerBuilder("testForceKillTask").
shutdownGracePeriodMs(1).
command("bash", tempFile.getAbsolutePath()).