Add a Pub source for pub.dartlang.org.

utils/pub/io.dart

Index: utils/pub/io.dart
diff --git a/utils/pub/io.dart b/utils/pub/io.dart
index 3f3c9d0a37f469ac7f25a3b1e6261cc5ce9fdc75..039965ee92e7056616f5d596f6df4543b45f5437 100644
--- a/utils/pub/io.dart
+++ b/utils/pub/io.dart
@@ -8,6 +8,7 @@
 #library('io');
 
 #import('dart:io');
+#import('dart:uri');
 
 /** Gets the current working directory. */
 String get workingDir() => new File('.').fullPathSync();
@@ -263,6 +264,57 @@ Future<File> createSymlink(from, to) {
 String getFullPath(entry) => new File(_getPath(entry)).fullPathSync();
 
 /**
+ * Opens an input stream for a HTTP GET request to [uri], which may be a
+ * [String] or [Uri].
+ */
+InputStream httpGet(uri) {
+  var resultStream = new ListInputStream();
+  var connection = new HttpClient().getUrl(_getUri(uri));
+
+  // TODO(nweiz): propagate this error to the return value. See issue 3657.
+  connection.onError = (e) { throw e; };
+  connection.onResponse = (response) {
+    if (response.statusCode >= 400) {
+      // TODO(nweiz): propagate this error to the return value. See issue 3657.
+      throw new Exception(
+          "HTTP request for $uri failed with status ${response.statusCode}");
+    }
+
+    pipeInputToInput(response.inputStream, resultStream);
+  };
+
+  return resultStream;
+}
+
+/**
+ * Takes all input from [source] and writes it to [sink].
+ *
+ * [onClosed] is called when [source] is closed.
+ */
+void pipeInputToInput(InputStream source, ListInputStream sink,
+    [void onClosed()]) {
+  source.onClosed = () {
+    sink.markEndOfStream();
+    if (onClosed != null) onClosed();
+  };
+  source.onData = () => sink.write(source.read());
+  // TODO(nweiz): propagate this error to the sink. See issue 3657.
+  source.onError = (e) { throw e; };
+}
+
+/**
+ * Buffers all input from an InputStream and returns it as a future.
+ */
+Future<List<int>> consumeInputStream(InputStream stream) {
+  var completer = new Completer<List<int>>();
+  var buffer = <int>[];
+  stream.onClosed = () => completer.complete(buffer);
+  stream.onData = () => buffer.addAll(stream.read());
+  stream.onError = (e) => completer.completeException(e);
+  return completer.future;
+}
+
+/**
  * Spawns and runs the process located at [executable], passing in [args].
  * Returns a [Future] that will complete the results of the process after it
  * has ended.
@@ -357,6 +409,24 @@ Future<bool> get isGitInstalled() {
 }
 
 /**
+ * Extracts a `.tar.gz` file from [stream] to [destination], which can be a
+ * directory or a path. Returns whether or not the extraction was successful.
+ */
+Future<bool> extractTarGz(InputStream stream, destination) {
+  var process = Process.start("tar",
+      ["--extract", "--gunzip", "--directory", _getPath(destination)]);
+  var completer = new Completer<int>();
+
+  stream.pipe(process.stdin);
+  process.stdout.pipe(stdout, close: false);
+  process.stderr.pipe(stderr, close: false);
+
+  process.onExit = completer.complete;
+  process.onError = completer.completeException;
+  return completer.future.transform((exitCode) => exitCode == 0);
+}
+
+/**
  * Contains the results of invoking a [Process] and waiting for it to complete.
  */
 class PubProcessResult {
@@ -389,3 +459,11 @@ Directory _getDirectory(entry) {
   if (entry is Directory) return entry;
   return new Directory(entry);
 }
+
+/**
+ * Gets a [Uri] for [uri], which can either already be one, or be a [String].
+ */
+Uri _getUri(uri) {
+  if (uri is Uri) return uri;
+  return new Uri.fromString(uri);
+}