Introduce a BuckBuild that mirrors the existing Build test helper

Still have some teething problems to work through before
this can be used in anger :)

java/client/test/org/openqa/selenium/BUCK

@@ -29,6 +29,7 @@ java_library(name = 'large-tests',
 
 java_library(name = 'helpers',
   srcs = [
+    'BuckBuild.java',
     'Build.java',
     'Pages.java',
     'ParallelTestRunner.java',

java/client/test/org/openqa/selenium/BuckBuild.java

@@ -0,0 +1,168 @@
+package org.openqa.selenium;
+
+import static com.google.common.base.StandardSystemProperty.LINE_SEPARATOR;
+import static java.nio.file.StandardCopyOption.REPLACE_EXISTING;
+import static org.openqa.selenium.Platform.WINDOWS;
+import static org.openqa.selenium.testing.DevMode.isInDevMode;
+
+import com.google.common.base.Preconditions;
+import com.google.common.base.Splitter;
+import com.google.common.base.StandardSystemProperty;
+import com.google.common.collect.ImmutableList;
+import com.google.common.hash.HashCode;
+import com.google.common.hash.Hashing;
+
+import org.openqa.selenium.os.CommandLine;
+import org.openqa.selenium.testing.InProject;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.List;
+import java.util.logging.Logger;
+
+public class BuckBuild {
+  private static Logger log = Logger.getLogger(BuckBuild.class.getName());
+
+  private String target;
+
+  public BuckBuild of(String target) {
+    this.target = target;
+    return this;
+  }
+
+  public Path go() throws IOException {
+    Path projectRoot = InProject.locate("Rakefile").toPath().getParent();
+
+    if (!isInDevMode()) {
+      // we should only need to do this when we're in dev mode
+      // when running in a test suite, our dependencies should already
+      // be listed.
+      log.info("Not in dev mode. Ignoring attempt to build: " + target);
+      return findOutput(projectRoot);
+    }
+
+    if (target == null || "".equals(target)) {
+      throw new IllegalStateException("No targets specified");
+    }
+    System.out.println("\nBuilding " + target + " ...");
+
+    ImmutableList.Builder<String> builder = ImmutableList.builder();
+    findBuck(projectRoot, builder);
+    builder.add("build");
+    builder.add(target);
+
+    ImmutableList<String> command = builder.build();
+    CommandLine commandLine = new CommandLine(command.toArray(new String[command.size()]));
+    commandLine.copyOutputTo(System.err);
+    commandLine.execute();
+
+    if (!commandLine.isSuccessful()) {
+      throw new WebDriverException("Build failed! " + target);
+    }
+
+    return findOutput(projectRoot);
+  }
+
+  private Path findOutput(Path projectRoot) throws IOException {
+    ImmutableList.Builder<String> builder = ImmutableList.builder();
+    findBuck(projectRoot, builder);
+    builder.add("targets", "--show-output", target);
+
+    ImmutableList<String> command = builder.build();
+    CommandLine commandLine = new CommandLine(command.toArray(new String[command.size()]));
+    commandLine.copyOutputTo(System.err);
+    commandLine.execute();
+
+    if (!commandLine.isSuccessful()) {
+      throw new WebDriverException("Unable to find output! " + target);
+    }
+
+    String[] allLines = commandLine.getStdOut().split(LINE_SEPARATOR.value());
+    String lastLine = allLines[allLines.length -1 ];
+
+    List<String> outputs = Splitter.on(' ').limit(2).splitToList(lastLine);
+    if (outputs.size() != 2) {
+      throw new WebDriverException(
+        String.format("Unable to find output! %s, %s", target, lastLine));
+    }
+
+    Path output = projectRoot.resolve(outputs.get(1));
+
+    if (!Files.exists(output)) {
+      throw new WebDriverException(
+        String.format("Found output, but it does not exist: %s, %s", target, output));
+    }
+
+    return output;
+  }
+
+  private void findBuck(Path projectRoot, ImmutableList.Builder<String> builder) throws IOException {
+    Path noBuckCheck = projectRoot.resolve(".nobuckcheck");
+
+    // If there's a .nobuckcheck in the root of the file, and we can execute "buck", then assume
+    // that the developer knows what they're doing. Ha! Ahaha! Ahahahaha!
+    if (Files.exists(noBuckCheck)) {
+      String buckCommand = CommandLine.find("buck");
+      if (buckCommand != null) {
+        builder.add(buckCommand);
+        return;
+      }
+    }
+
+    downloadBuckPexIfNecessary(builder);
+  }
+
+  private void downloadBuckPexIfNecessary(ImmutableList.Builder<String> builder)
+    throws IOException {
+    String buckVersion = new String(Files.readAllBytes(Paths.get(".buckversion"))).trim();
+
+    Path pex = Paths.get(
+      StandardSystemProperty.USER_HOME.value(), ".crazyfun", "buck", buckVersion, "buck.pex");
+
+    String expectedHash = new String(Files.readAllBytes(Paths.get(".buckhash"))).trim();
+    HashCode md5 = Files.exists(pex) ?
+                   Hashing.md5().hashBytes(Files.readAllBytes(pex)) :
+                   HashCode.fromString("aa");  // So we have a non-null value
+
+    if (!Files.exists(pex) || !expectedHash.equals(md5.toString())) {
+      log.warning("Downloading PEX");
+
+      if (!Files.exists(pex.getParent())) {
+        Files.createDirectories(pex.getParent());
+      }
+
+      URL url = new URL(String.format(
+          "https://github.com/SeleniumHQ/buck/releases/download/buck-release-%s/buck.pex",
+          buckVersion));
+      HttpURLConnection connection = (HttpURLConnection) url.openConnection();
+      connection.setInstanceFollowRedirects(true);
+      Files.copy(connection.getInputStream(), pex, REPLACE_EXISTING);
+      // Do our best to make this executable
+      pex.toFile().setExecutable(true);
+    }
+
+    md5 = Hashing.md5().hashBytes(Files.readAllBytes(pex));
+    if (!expectedHash.equals(md5.toString())) {
+      throw new WebDriverException("Unable to confirm that download is valid");
+    }
+
+    if (Platform.getCurrent().is(WINDOWS)) {
+      String python = CommandLine.find("python2");
+      if (python == null) {
+        python = CommandLine.find("python");
+      }
+      Preconditions.checkNotNull(python, "Unable to find python executable");
+      builder.add(python);
+    }
+
+    builder.add(pex.toAbsolutePath().toString());
+  }
+
+  public static void main(String[] args) throws IOException {
+    new BuckBuild().of("se3-server").go();
+  }
+}