Rewrite the Command API
Important: the simplified API now defaults to forwarding interrupts to
subprocesses. I did audit all the call sites, and I think this is a safe change
to make.
- Properly support timeouts with all implementations
- Simplify the API
- only provide two flavours of blocking calls, which require no input and
forward interrupts; this is the most common usage
- provide a number of async calls, which optionally takes input, and a flag
whether to forward interrupts
- only support input streams, no byte arrays or other 'convenience features'
that are rarely needed and unnecessarily increase the surface area
- use java.time.Duration to specify timeout; for consistency, interpret a
timeout of <= 0 as no timeout (i.e., including rather than excluding 0)
- KillableObserver and subclasses are no longer part of the public API, but
still used to implement timeouts if the Subprocess.Factory does not support
them
- Update the documentation for Command
- Update all callers; most callers now use the simplified API
PiperOrigin-RevId: 164716782
diff --git a/src/main/java/com/google/devtools/build/lib/shell/Consumers.java b/src/main/java/com/google/devtools/build/lib/shell/Consumers.java
index 47515d7..b3864d3 100644
--- a/src/main/java/com/google/devtools/build/lib/shell/Consumers.java
+++ b/src/main/java/com/google/devtools/build/lib/shell/Consumers.java
@@ -13,6 +13,7 @@
// limitations under the License.
package com.google.devtools.build.lib.shell;
+import com.google.common.base.Preconditions;
import com.google.common.util.concurrent.Uninterruptibles;
import java.io.ByteArrayOutputStream;
import java.io.Closeable;
@@ -31,11 +32,10 @@
/**
* This class provides convenience methods for consuming (actively reading)
* output and error streams with different consumption policies:
- * discarding ({@link #createDiscardingConsumers()},
* accumulating ({@link #createAccumulatingConsumers()},
* and streaming ({@link #createStreamingConsumers(OutputStream, OutputStream)}).
*/
-class Consumers {
+final class Consumers {
private static final Logger log =
Logger.getLogger("com.google.devtools.build.lib.shell.Command");
@@ -45,33 +45,26 @@
private static final ExecutorService pool =
Executors.newCachedThreadPool(new AccumulatorThreadFactory());
- static OutErrConsumers createDiscardingConsumers() {
- return new OutErrConsumers(new DiscardingConsumer(),
- new DiscardingConsumer());
- }
-
static OutErrConsumers createAccumulatingConsumers() {
- return new OutErrConsumers(new AccumulatingConsumer(),
- new AccumulatingConsumer());
+ return new OutErrConsumers(new AccumulatingConsumer(), new AccumulatingConsumer());
}
- static OutErrConsumers createStreamingConsumers(OutputStream out,
- OutputStream err) {
- return new OutErrConsumers(new StreamingConsumer(out),
- new StreamingConsumer(err));
+ static OutErrConsumers createStreamingConsumers(OutputStream out, OutputStream err) {
+ Preconditions.checkNotNull(out);
+ Preconditions.checkNotNull(err);
+ return new OutErrConsumers(new StreamingConsumer(out), new StreamingConsumer(err));
}
static class OutErrConsumers {
-
private final OutputConsumer out;
private final OutputConsumer err;
- private OutErrConsumers(final OutputConsumer out, final OutputConsumer err){
+ private OutErrConsumers(final OutputConsumer out, final OutputConsumer err) {
this.out = out;
this.err = err;
}
- void registerInputs(InputStream outInput, InputStream errInput, boolean closeStreams){
+ void registerInputs(InputStream outInput, InputStream errInput, boolean closeStreams) {
out.registerInput(outInput, closeStreams);
err.registerInput(errInput, closeStreams);
}
