kz930 commented on code in PR #7207: URL: https://github.com/apache/texera/pull/7207#discussion_r3769803777
########## common/workflow-operator/src/test/scala/org/apache/texera/amber/util/python/PythonWorkerPoolSpec.scala: ########## @@ -0,0 +1,243 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ + +package org.apache.texera.amber.util.python + +import com.fasterxml.jackson.databind.node.ObjectNode +import org.apache.texera.amber.util.JSONUtils.objectMapper +import org.scalatest.funsuite.AnyFunSuite + +import java.util.concurrent.{Executors, TimeUnit} +import scala.concurrent.duration._ +import scala.concurrent.{Await, ExecutionContext, ExecutionContextExecutorService, Future} +import scala.util.Try + +/** + * What the pool owes a caller when a worker misbehaves. An ordinary job failure + * is the other suites' business; this one is about a worker that stays alive and + * stops taking part, which is the case that does not end by itself: a crash + * closes the pipe and the pending read returns, while silence would hold the + * caller forever — neither a read nor a write on a process pipe answers an + * interrupt or a deadline, so no suite-level timeout can release one. + * + * Every wait here is bounded and runs on daemon threads, so a regression fails + * these tests instead of wedging the run: a lost non-daemon thread parked on a + * pipe would keep the JVM, and the build, alive. + * + * The fixture worker is stdlib-only and runs under `-I -S`, so this needs an + * interpreter but none of the operator packages. + */ +final class PythonWorkerPoolSpec extends AnyFunSuite { + + private val HangingWorker = "/python/hanging_worker.py" + + /** Short enough to keep the suite quick, far enough above process startup to + * not be mistaken for one: a fixture asked to hang never answers at all, so + * these deadlines cannot race it. + */ + private val ShortTimeouts: PythonWorkerPool.Timeouts = + PythonWorkerPool.Timeouts(responseMillis = 1500, startupMillis = 1500) + + /** For the case that interrupts its own callers: far enough out that they are + * certainly still waiting on the worker, not already past their deadline. + */ + private val PatientTimeouts: PythonWorkerPool.Timeouts = + PythonWorkerPool.Timeouts(responseMillis = 60000, startupMillis = 60000) + + /** Ceiling on a whole case, well above the deadlines under test. Reaching it + * means something never gave up. + */ + private val Bound: FiniteDuration = 25.seconds + + /** Any interpreter serves — the fixture imports only `json` and `time` — so + * this deliberately skips the configured `python.path` the suites that need + * pandas resolve. A machine without one cancels rather than fails. + */ + private lazy val python: String = { + def isRunnable(exe: String): Boolean = + Try(new ProcessBuilder(exe, "--version").redirectErrorStream(true).start()).toOption + .exists { p => + if (p.waitFor(5, TimeUnit.SECONDS)) p.exitValue() == 0 else { p.destroyForcibly(); false } + } + + List("python3", "python", "py").find(isRunnable).getOrElse(cancel("no runnable python")) Review Comment: Fixed in `39e74b76` with the `withFixture` you suggested. Reproduced first by pointing the probe at names that do not exist: 5 failed and 2 succeeded before, 8 cancel after. ########## common/workflow-operator/src/test/scala/org/apache/texera/amber/util/python/PythonWorkerPool.scala: ########## @@ -0,0 +1,492 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ + +package org.apache.texera.amber.util.python + +import com.fasterxml.jackson.databind.node.ObjectNode +import com.typesafe.scalalogging.LazyLogging +import org.apache.texera.amber.util.JSONUtils.objectMapper + +import java.io.{BufferedReader, BufferedWriter, InputStreamReader, OutputStreamWriter} +import java.nio.charset.StandardCharsets +import java.nio.file.{Files, Path, StandardCopyOption} +import java.util.concurrent.{ + Callable, + ConcurrentHashMap, + ExecutionException, + ExecutorService, + Executors, + LinkedBlockingQueue, + TimeUnit, + TimeoutException +} +import java.util.concurrent.atomic.AtomicInteger +import scala.annotation.tailrec +import scala.collection.mutable +import scala.jdk.CollectionConverters._ +import scala.util.control.NonFatal + +/** + * Pools of persistent Python "worker" processes that eliminate the per-call + * interpreter-boot + import cost a test otherwise pays on every subprocess + * spawn. Testing operators one at a time does not scale when each one costs a + * spawn: a bare `-I -S` interpreter boots in ~25 ms, and once pandas and plotly + * are imported a spawn costs ~260-310 ms — mostly the imports — dwarfing + * the ~4 ms of real work a job does. A worker pays that once at startup, then + * serves many jobs over its lifetime, so N spawns become one. + * + * Lives in test scope here, rather than beside a single caller, because tests in + * several modules run generated operator code and would otherwise each + * hand-roll a driver, a stdout protocol and a timeout. Other modules reach it + * through a `test->test` dependency on this one. + * + * Generic over the worker script — the pool never interprets the payload — so + * one implementation serves a syntax check, template execution and DataFrame + * comparison alike. Each distinct (resource, interpreterArgs, launchArgs, + * python, env) combination gets its own sub-pool. + * + * Protocol (line-delimited JSON, shared by all worker scripts): + * startup worker -> pool: {"ready": true} + * request pool -> worker: <caller-supplied JSON object>\n + * response worker -> pool: {"exit": <int>, "stdout": "...", "stderr": "..."}\n + * + * Concurrency: callers submit from several threads at once — one test fanning + * its cases out, or suites running in parallel — so each sub-pool holds up to + * [[maxWorkers]] workers, each serving one job at a time (borrow -> run -> + * return). A worker script may chdir per job, so a worker must never run two + * jobs at once — the borrow/return discipline guarantees that. + * + * Robustness: an ordinary *job* failure comes back as an [[Outcome]] with + * `exit != 0` (worker keeps running). A hard interpreter crash ends a worker; + * the pool detects the EOF / broken pipe, discards it, and throws + * [[WorkerDiedException]] so the caller can fall back to a one-shot subprocess + * — behavior is then never worse than the pre-pool path. A worker that stays + * alive but stops answering ends the same way, on the [[Timeouts]] below. + */ +object PythonWorkerPool extends LazyLogging { + + /** Worker response: process-like exit code plus captured streams. */ + final case class Outcome(exit: Int, stdout: String, stderr: String) + + /** Thrown for a worker the pool could not give out or keep: one that would not + * start, one that never signalled ready, or one that died or fell silent + * mid-job. Callers catch this and fall back to a one-shot subprocess. + */ + final class WorkerDiedException(message: String, cause: Throwable = null) + extends RuntimeException(message, cause) + + /** Feature toggle. `TEXERA_TEST_PYTHON_WORKER=0` (or `false`/`off`) forces the + * one-subprocess-per-call paths everywhere — an escape hatch for debugging a + * suspected isolation leak. Default on. + */ + val enabled: Boolean = + !sys.env + .get("TEXERA_TEST_PYTHON_WORKER") + .map(_.trim.toLowerCase) + .exists(Set("0", "false", "off")) + + /** Max live workers per sub-pool, so callers on distinct worker + * scripts add up rather than share this bound. Defaults to 4, override via + * `TEXERA_TEST_PYTHON_WORKERS`. Public so a caller fanning out jobs within one + * test can size that fan-out to the workers it will get. + */ + val maxWorkers: Int = + sys.env + .get("TEXERA_TEST_PYTHON_WORKERS") + .flatMap(s => scala.util.Try(s.trim.toInt).toOption) + .filter(_ > 0) + .getOrElse(4) + + /** How long a caller waits on a worker before the pool kills and discards it. + * A read on a process pipe cannot be interrupted — a suite or executor timeout + * leaves the reading thread stuck on it — so a worker that stays alive without + * answering has to be bounded here. `responseMillis` keeps the 30 seconds the + * one-shot spawn this pool replaced allowed a job; `startupMillis` is longer because + * a worker imports its libraries before it reports ready, and a loaded CI + * machine makes that slow. Override in seconds via + * `TEXERA_TEST_PYTHON_WORKER_TIMEOUT` / `TEXERA_TEST_PYTHON_WORKER_STARTUP_TIMEOUT`. + */ + final case class Timeouts(responseMillis: Long, startupMillis: Long) + + object Timeouts { + private def envSeconds(name: String, default: Long): Long = + sys.env + .get(name) + .flatMap(s => scala.util.Try(s.trim.toLong).toOption) + .filter(_ > 0) + .getOrElse(default) * 1000 + + val Default: Timeouts = Timeouts( + responseMillis = envSeconds("TEXERA_TEST_PYTHON_WORKER_TIMEOUT", 30), + startupMillis = envSeconds("TEXERA_TEST_PYTHON_WORKER_STARTUP_TIMEOUT", 60) + ) + } + + /** + * Run one job through a pooled worker for `resourcePath`, launched as + * `pythonExe <interpreterArgs> <script> <launchArgs>` with extra environment + * `env`. `request` is the worker-specific JSON payload (the pool does not + * interpret it). Throws [[WorkerDiedException]] for every worker the pool could + * not give out or keep — one that would not start, would not report ready, or + * died mid-job — so one `catch` covers a caller's whole fallback. + * + * `interpreterArgs` are the flags that must precede the script — a syntax + * checker wants `-I -S` so it validates under the same isolation a one-shot + * `python -I -S -m py_compile` gave it. `launchArgs` are the script's own + * (e.g. `--serve`), and `env` carries what a flag cannot — though not + * PYTHONPATH or any other PYTHON* var, which the `-I` above makes CPython ignore. + * All three are part of a worker's identity: one started differently is not + * interchangeable, so it gets its own sub-pool. `timeouts` is not — it bounds + * this call, so a caller whose jobs are slower than most can raise it without + * splitting the pool. + */ + def run( + resourcePath: String, + launchArgs: Seq[String], + pythonExe: String, + request: ObjectNode, + env: Map[String, String] = Map.empty, + interpreterArgs: Seq[String] = Seq.empty, + timeouts: Timeouts = Timeouts.Default + ): Outcome = { + val pool = pools.computeIfAbsent( + Key(resourcePath, pythonExe, interpreterArgs.toList, launchArgs.toList, env.toList.sorted), + _ => new Pool(resourcePath, launchArgs, pythonExe, env, interpreterArgs) + ) + pool.run(request, timeouts) + } + + /** What makes two launches the same worker. Compared field by field rather than + * as one joined string, so a value carrying whatever the separator was — a + * python path with a space in it, a PYTHONPATH — cannot make two different + * launches share a pool. + */ + private final case class Key( + resourcePath: String, + pythonExe: String, + interpreterArgs: List[String], + launchArgs: List[String], + env: List[(String, String)] + ) + + /** How long a caller at the worker cap waits before re-examining it. Not a + * deadline — see [[Pool.borrow]]. + */ + private val CapRecheckMillis: Long = 250 + + private val pools = new ConcurrentHashMap[Key, Pool]() + + Runtime.getRuntime.addShutdownHook(new Thread(() => shutdownAll())) + + private def shutdownAll(): Unit = + pools.values().forEach(_.shutdown()) + + // A single sub-pool: up to `maxWorkers` live workers for one worker script. + private final class Pool( + resourcePath: String, + launchArgs: Seq[String], + pythonExe: String, + env: Map[String, String], + interpreterArgs: Seq[String] + ) { + private val idle = new LinkedBlockingQueue[Worker]() + private val liveCount = new AtomicInteger(0) + private val all = mutable.Set.empty[Worker] // guarded by `all` + @volatile private var script: Path = _ + + def run(request: ObjectNode, timeouts: Timeouts): Outcome = { + val w = borrow(timeouts) + try { + val outcome = w.run(request, timeouts.responseMillis) + idle.offer(w) // healthy — return to pool + outcome + } catch { + // Every throw, not only a WorkerDiedException: an interrupt on this + // thread — what an executor's `shutdownNow` sends — leaves the blocking + // read or write as an InterruptedException, which `NonFatal` excludes and + // [[Worker.run]] therefore does not wrap. A worker left neither returned + // nor discarded costs this sub-pool a slot for the life of the JVM, and + // its answer may still be in flight, so it cannot be reused either way. + case e: Throwable => + discard(w) + throw e + } + } + + @tailrec + private def borrow(timeouts: Timeouts): Worker = { + val existing = idle.poll() + if (existing != null) existing + else if (liveCount.getAndIncrement() < maxWorkers) { + try create(timeouts) + catch { + case e: Throwable => + liveCount.decrementAndGet() + throw e + } + } else { + liveCount.decrementAndGet() + // At the cap. Waiting outright for a returned worker would strand this + // caller when the ones ahead are discarded instead: a discard frees a + // slot without putting anything back. So wait only briefly, then look at + // the cap again — the next pass starts a replacement. A long queue still + // waits as long as it takes; that is the caller's own backlog, not a hang. + val returned = idle.poll(CapRecheckMillis, TimeUnit.MILLISECONDS) + if (returned != null) returned else borrow(timeouts) + } + } + + private def create(timeouts: Timeouts): Worker = { + val cmd = + (((pythonExe +: interpreterArgs) :+ ensureScript().toString) ++ launchArgs).asJava + val pb = new ProcessBuilder(cmd).redirectErrorStream(false) + env.foreach { case (k, v) => pb.environment().put(k, v) } + // A worker that cannot be started is a worker death like any other, so it + // leaves through the same exception: `start` throws a bare IOException — no + // interpreter at that path, or the OS out of processes under a fan-out — and + // a caller's fallback is written against [[WorkerDiedException]]. + val process = + try pb.start() + catch { + case NonFatal(e) => + throw new WorkerDiedException( + s"could not start python worker for $resourcePath: ${e.getMessage}", + e + ) + } + val w = new Worker(process, s"$resourcePath ${launchArgs.mkString(" ")}".trim) + // Anything thrown before the worker joins `all` — a startup that timed out, + // an interrupt on this thread — leaves an interpreter nothing else would + // reap: not the caller, which never gets the handle, and not the shutdown + // hook, which walks `all`. `destroy` is idempotent, so a worker that already + // killed itself on the way out is no exception to that. + try w.awaitReady(timeouts.startupMillis) + catch { + case e: Throwable => + w.destroy() + throw e + } + all.synchronized(all.add(w)) + logger.debug(s"Started python worker for $resourcePath (live=${liveCount.get}/$maxWorkers)") + w + } + + private def discard(w: Worker): Unit = { + all.synchronized(all.remove(w)) + liveCount.decrementAndGet() + w.destroy() + } + + private def ensureScript(): Path = { + if (script == null) synchronized { + if (script == null) { + val stream = getClass.getResourceAsStream(resourcePath) + require(stream != null, s"worker script not found on classpath at $resourcePath") + try { + val tmp = Files.createTempFile("py-worker-", ".py") + Files.copy(stream, tmp, StandardCopyOption.REPLACE_EXISTING) + tmp.toFile.deleteOnExit() + script = tmp + } finally stream.close() + } + } + script + } + + def shutdown(): Unit = + all.synchronized { + all.foreach(_.destroy()) + all.clear() + } + } + + // One live worker process plus its framed-JSON stdin and background drains of + // its stdout (the protocol) and stderr (only non-empty on a hard crash). + private final class Worker(process: Process, label: String) { + private val stdin: BufferedWriter = + new BufferedWriter(new OutputStreamWriter(process.getOutputStream, StandardCharsets.UTF_8)) + private val errBuf = new StringBuilder + + // Protocol lines the worker has written, `None` marking end of stream. A + // dedicated thread owns the blocking read so a caller can wait with a + // timeout: `readLine` on a process pipe answers neither an interrupt nor a + // deadline, and only closing the pipe — killing the process — releases it. + private val lines = new LinkedBlockingQueue[Option[String]]() + + // Owns the writing end for the same reason. + private val writer: ExecutorService = Executors.newSingleThreadExecutor { r => + val t = new Thread(r, "python-worker-stdin") + t.setDaemon(true) + t + } + + private val outThread: Thread = { + val t = new Thread(() => { + val r = + new BufferedReader(new InputStreamReader(process.getInputStream, StandardCharsets.UTF_8)) + try { + var line = r.readLine() + while (line != null) { + lines.put(Some(line)) + line = r.readLine() + } + } catch { case NonFatal(_) => () } + finally lines.put(None) + }) + t.setDaemon(true) + t.setName("python-worker-stdout") + t.start() + t + } + + private val errThread: Thread = { + val t = new Thread(() => { + val r = + new BufferedReader(new InputStreamReader(process.getErrorStream, StandardCharsets.UTF_8)) + try { + var line = r.readLine() + while (line != null) { + errBuf.synchronized(errBuf.append(line).append('\n')) + line = r.readLine() + } + } catch { case NonFatal(_) => () } + }) + t.setDaemon(true) + t.setName("python-worker-stderr") + t.start() + t + } + + /** Wait for the worker's startup `{"ready": true}`; if it dies first (e.g. an + * import failed) or never gets there, surface its stderr. A worker that + * fails here is killed: it is not in the pool's set yet, so nothing else + * will reap it. + * + * A first line that is not the protocol at all counts as not ready, rather + * than throwing whatever the parser throws: the caller's contract here is + * [[WorkerDiedException]], and an escape past it would leave this + * interpreter with nothing to reap it. The line goes into the message — + * stderr is empty when a script writes its noise to stdout. + */ + def awaitReady(timeoutMillis: Long): Unit = { + val line = nextLine(timeoutMillis, "signal ready") + val ready = + try objectMapper.readTree(line).path("ready").asBoolean(false) + catch { case NonFatal(_) => false } + if (!ready) { + destroy() + throw new WorkerDiedException( + s"python worker [$label] did not signal ready; it wrote: ${abbreviate(line)}." + + s" stderr:\n${drainErr()}" + ) + } + } + + def run(request: ObjectNode, timeoutMillis: Long): Outcome = + try { + send(request, timeoutMillis) + val node = objectMapper.readTree(nextLine(timeoutMillis, "answer")) + Outcome( + node.path("exit").asInt(1), Review Comment: Yes, a `WorkerDiedException` is the right answer, fixed in `12046730`. The worker is discarded and the caller's spawn fallback covers it; the fixture and spec gain a case that answers without the field. ########## common/workflow-operator/build.sbt: ########## @@ -35,6 +35,19 @@ ThisBuild / conflictManager := ConflictManager.latestRevision // Restrict parallel execution of tests to avoid conflicts Global / concurrentRestrictions += Tags.limit(Tags.Test, 1) +// A test needing more than a bare Python interpreter is tagged, so the amber job +// excludes it and amber-integration, which installs operator-requirements.txt, Review Comment: Applied in `ed51a857`. ########## common/workflow-operator/build.sbt: ########## @@ -35,6 +35,19 @@ ThisBuild / conflictManager := ConflictManager.latestRevision // Restrict parallel execution of tests to avoid conflicts Global / concurrentRestrictions += Tags.limit(Tags.Test, 1) +// A test needing more than a bare Python interpreter is tagged, so the amber job +// excludes it and amber-integration, which installs operator-requirements.txt, +// runs it. The amber job already sets this env var on the step that invokes +// WorkflowOperator/jacoco, so no workflow change is needed for the exclusion. +// +// PythonCodeRawInvalidTextSpec reads the same env var and value directly, to tell +// a missing package in amber-integration (a defect) from one on a developer's +// machine (a local-setup fact). Renaming either without the other leaves that test +// cancelling in the job meant to fail it. Review Comment: Applied in `ed51a857`. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
