S19: consume versioned engineering resources and move landscape documentation

generated/tooling/format/Format.java

@@ -0,0 +1,136 @@
+import com.palantir.javaformat.java.Formatter;
+import com.palantir.javaformat.java.JavaFormatterOptions;
+import java.nio.file.*;
+import java.security.MessageDigest;
+import java.util.*;
+import org.openrewrite.*;
+import org.openrewrite.internal.InMemoryLargeSourceSet;
+import org.openrewrite.text.*;
+
+/** Source-launcher bootstrap: no project-specific artifact is resolved or installed. */
+public class Format {
+    public static void main(String[] args) throws Exception {
+        Path root = Path.of(args[0]).toAbsolutePath().normalize();
+        boolean check = switch (args[1]) {
+            case "check" -> true;
+            case "apply" -> false;
+            default -> throw new IllegalArgumentException("format.mode must be apply or check");
+        };
+        Path cacheFile = root.resolve("target/palantir-cache.properties");
+        var cache = new Properties();
+        if (Files.exists(cacheFile)) {
+            try (var input = Files.newInputStream(cacheFile)) {
+                cache.load(input);
+            }
+        }
+        String configuration = digest(Files.readString(root.resolve("pom.xml"))
+                + Files.readString(root.resolve("generated/tooling/format/Format.java"))
+                + System.getProperty("java.version")
+                + System.getProperty("java.class.path"));
+        if (!configuration.equals(cache.getProperty("configuration"))) cache.clear();
+        cache.setProperty("configuration", configuration);
+        List<SourceFile> sources = new ArrayList<>();
+        var settings = new Properties();
+        try (var input = Files.newInputStream(root.resolve("engineering.properties"))) {
+            settings.load(input);
+        }
+        for (String directory :
+                settings.getProperty("FORMAT_DIRECTORIES", "backend/src").split(",")) {
+            if (!Files.isDirectory(root.resolve(directory))) continue;
+            try (var paths = Files.walk(root.resolve(directory))) {
+                for (Path path : paths.filter(p -> p.toString().endsWith(".java"))
+                        .sorted()
+                        .toList()) {
+                    try {
+                        String content = Files.readString(path);
+                        String key = root.relativize(path).toString();
+                        if (!digest(content).equals(cache.getProperty(key))) {
+                            sources.add(PlainText.builder()
+                                    .sourcePath(root.relativize(path))
+                                    .text(content)
+                                    .build());
+                        }
+                    } catch (Exception error) {
+                        throw new IllegalStateException(path + ": " + error.getMessage(), error);
+                    }
+                }
+            }
+        }
+        var context = new InMemoryExecutionContext(error -> {
+            throw new IllegalStateException("Formatting failed: " + error.getMessage(), error);
+        });
+        var results = new PalantirRecipe()
+                .run(new InMemoryLargeSourceSet(sources), context)
+                .getChangeset()
+                .getAllResults();
+        for (Result result : results) {
+            System.out.println((check ? "Needs formatting: " : "Formatted: ")
+                    + result.getAfter().getSourcePath());
+        }
+        if (check && !results.isEmpty()) {
+            throw new IllegalStateException("Run mvn -N exec:exec@format to apply Palantir formatting.");
+        }
+        // Complete parsing/formatting before writing any maintained file. Each replacement is atomic.
+        if (!check) {
+            for (Result result : results) {
+                Path destination = root.resolve(result.getAfter().getSourcePath());
+                Path temporary = Files.createTempFile(destination.getParent(), ".palantir-", ".tmp");
+                try {
+                    Files.writeString(temporary, result.getAfter().printAll());
+                    Files.setPosixFilePermissions(temporary, Files.getPosixFilePermissions(destination));
+                    Files.move(
+                            temporary,
+                            destination,
+                            StandardCopyOption.ATOMIC_MOVE,
+                            StandardCopyOption.REPLACE_EXISTING);
+                } finally {
+                    Files.deleteIfExists(temporary);
+                }
+            }
+        }
+        for (SourceFile source : sources) {
+            cache.setProperty(
+                    source.getSourcePath().toString(), digest(Files.readString(root.resolve(source.getSourcePath()))));
+        }
+        Files.createDirectories(cacheFile.getParent());
+        try (var output = Files.newOutputStream(cacheFile)) {
+            cache.store(output, "Successfully formatted content only");
+        }
+        System.out.println(
+                "Palantir " + args[1] + ": " + sources.size() + " Java files, " + results.size() + " differences");
+    }
+
+    static String digest(String value) throws Exception {
+        return HexFormat.of()
+                .formatHex(MessageDigest.getInstance("SHA-256")
+                        .digest(value.getBytes(java.nio.charset.StandardCharsets.UTF_8)));
+    }
+
+    public static final class PalantirRecipe extends Recipe {
+        public String getDisplayName() {
+            return "Palantir Java Format";
+        }
+
+        public String getDescription() {
+            return "Apply the pinned Palantir engine and its native import handling.";
+        }
+
+        public TreeVisitor<?, ExecutionContext> getVisitor() {
+            return new PlainTextVisitor<ExecutionContext>() {
+                final Formatter formatter = Formatter.createFormatter(JavaFormatterOptions.builder()
+                        .style(JavaFormatterOptions.Style.PALANTIR)
+                        .formatJavadoc(false)
+                        .build());
+
+                @Override
+                public PlainText visitText(PlainText text, ExecutionContext context) {
+                    try {
+                        return text.withText(formatter.formatSourceAndFixImports(text.getText()));
+                    } catch (Exception | LinkageError error) {
+                        throw new IllegalStateException(text.getSourcePath() + ": " + error, error);
+                    }
+                }
+            };
+        }
+    }
+}