patch: allow option to allow comments in json files

Author: itzg

README.md

@@ -935,7 +935,8 @@ Provides simple operations to list network interface names and check existence
 ### patch
 
 ```
-Usage: mc-image-helper patch [-h] [--patch-env-prefix=<envPrefix>] FILE_OR_DIR
+Usage: mc-image-helper patch [-h] [--json-allow-comments]
+                             [--patch-env-prefix=<envPrefix>] FILE_OR_DIR
 Patches one or more existing files using JSON path based operations
 Supports the file formats:
 - JSON
@@ -945,6 +946,9 @@ Supports the file formats:
       FILE_OR_DIR   Path to a PatchSet json file or directory containing
                       PatchDefinition json files
   -h, --help        Show this usage and exit
+      --json-allow-comments
+                    Whether to allow comments in JSON files. Env: PATCH_JSON_ALLOW_COMMENTS
+                      Default: true
       --patch-env-prefix=<envPrefix>
                     Only placeholder variables with this prefix will be
                       processed

src/main/java/me/itzg/helpers/curseforge/CurseForgeInstaller.java

@@ -230,7 +230,7 @@ void install(String slug, InstallationEntryPoint entryPoint) {
             );
 
         } catch (IOException e) {
-            throw new GenericException("Failed to setup API caching", e);
+            throw new GenericException("File system issue during installation", e);
         }
     }
 

src/main/java/me/itzg/helpers/patch/JsonFileFormat.java

@@ -1,5 +1,6 @@
 package me.itzg.helpers.patch;
 
+import com.fasterxml.jackson.core.JsonParser.Feature;
 import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.core.util.DefaultPrettyPrinter;
 import com.fasterxml.jackson.core.util.Separators;
@@ -19,8 +20,9 @@ public class JsonFileFormat implements FileFormat {
     private final ObjectMapper objectMapper;
     private final ObjectWriter objectWriter;
 
-    public JsonFileFormat() {
-        objectMapper = new ObjectMapper();
+    public JsonFileFormat(boolean allowComments) {
+        objectMapper = new ObjectMapper()
+            .configure(Feature.ALLOW_COMMENTS, allowComments);
         objectWriter = objectMapper.writer(
                 new DefaultPrettyPrinter()
                     .withSeparators(

src/main/java/me/itzg/helpers/patch/PatchCommand.java

@@ -13,28 +13,39 @@
 import me.itzg.helpers.patch.model.PatchDefinition;
 import me.itzg.helpers.patch.model.PatchSet;
 import picocli.CommandLine;
+import picocli.CommandLine.Command;
+import picocli.CommandLine.Option;
+import picocli.CommandLine.Parameters;
 
-@CommandLine.Command(name = "patch",
+@Command(name = "patch",
     description = "Patches one or more existing files using JSON path based operations%n"
         + "Supports the file formats:%n"
         + "- JSON%n"
         + "- JSON5%n"
         + "- Yaml%n"
-        + "- TOML, but processed output is not pretty"
+        + "- TOML, but processed output is not pretty",
+    showDefaultValues = true
 )
 @Slf4j
 public class PatchCommand implements Callable<Integer> {
-    @CommandLine.Option(names = {"-h", "--help"}, usageHelp = true, description = "Show this usage and exit")
+
+    private static final String ENV_JSON_ALLOW_COMMENTS = "PATCH_JSON_ALLOW_COMMENTS";
+    @Option(names = {"-h", "--help"}, usageHelp = true, description = "Show this usage and exit")
     boolean showHelp;
 
-    @CommandLine.Option(names = "--patch-env-prefix",
+    @Option(names = "--patch-env-prefix",
             defaultValue = "CFG_",
-            showDefaultValue = CommandLine.Help.Visibility.ALWAYS,
             description = "Only placeholder variables with this prefix will be processed"
     )
     String envPrefix;
 
-    @CommandLine.Parameters(description = "Path to a PatchSet json file or directory containing PatchDefinition json files",
+    @Option(names = "--json-allow-comments", defaultValue = "${env:" + ENV_JSON_ALLOW_COMMENTS + ":-true}",
+        description = "Whether to allow comments in JSON files. Env: " + ENV_JSON_ALLOW_COMMENTS,
+        showDefaultValue = CommandLine.Help.Visibility.ALWAYS
+    )
+    boolean jsonAllowComments;
+
+    @Parameters(description = "Path to a PatchSet json file or directory containing PatchDefinition json files",
         paramLabel = "FILE_OR_DIR"
     )
     Path patches;

src/main/java/me/itzg/helpers/patch/PatchSetProcessor.java

@@ -29,15 +29,20 @@ public class PatchSetProcessor {
     private final Interpolator interpolator;
 
     public PatchSetProcessor(Interpolator interpolator) {
+        this(interpolator, false);
+    }
+
+    public PatchSetProcessor(Interpolator interpolator, boolean jsonAllowComments) {
         this.interpolator = interpolator;
+        fileFormats = new FileFormat[]{
+                new JsonFileFormat(jsonAllowComments),
+                new Json5FileFormat(),
+                new YamlFileFormat(),
+                new TomlFileFormat()
+        };
     }
 
-    private final FileFormat[] fileFormats = new FileFormat[]{
-            new JsonFileFormat(),
-            new Json5FileFormat(),
-            new YamlFileFormat(),
-            new TomlFileFormat()
-    };
+    private final FileFormat[] fileFormats;
 
     public void process(PatchSet patchSet) {
         log.debug("patchSet={}", patchSet);

src/test/java/me/itzg/helpers/patch/PatchSetProcessorTest.java

@@ -16,6 +16,7 @@
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Arrays;
+import java.util.stream.Stream;
 import me.itzg.helpers.env.EnvironmentVariablesProvider;
 import me.itzg.helpers.env.Interpolator;
 import me.itzg.helpers.patch.model.PatchDefinition;
@@ -25,6 +26,9 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.junit.jupiter.api.io.TempDir;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
 
@@ -34,29 +38,39 @@ class PatchSetProcessorTest {
     @Mock
     EnvironmentVariablesProvider environmentVariablesProvider;
 
-    @Test
-    void setInJson(@TempDir Path tempDir) throws IOException {
+    public static Stream<Arguments> setInJson_args() {
+        return Stream.of(
+            Arguments.arguments("testing.json", false),
+            Arguments.arguments("testing.json", true),
+            Arguments.arguments("testing-with-comment.json", true)
+        );
+    }
+
+    @ParameterizedTest
+    @MethodSource("setInJson_args")
+    void setInJson(String file, boolean allowComments, @TempDir Path tempDir) throws IOException {
         final Path src = tempDir.resolve("testing.json");
-        Files.copy(Paths.get("src/test/resources/patch/testing.json"), src);
+        Files.copy(Paths.get("src/test/resources/patch/" + file), src);
 
         final PatchSetProcessor processor = new PatchSetProcessor(
-                new Interpolator(environmentVariablesProvider, "CFG_")
+            new Interpolator(environmentVariablesProvider, "CFG_"),
+            allowComments
         );
 
         processor.process(new PatchSet()
-                .setPatches(singletonList(
-                    new PatchDefinition()
-                        .setFile(src.toString())
-                        .setOps(singletonList(
-                            new PatchSetOperation()
-                                .setPath("$.outer.field1")
-                                .setValue(new TextNode("new value"))
-                        ))
-                ))
+            .setPatches(singletonList(
+                new PatchDefinition()
+                    .setFile(src.toString())
+                    .setOps(singletonList(
+                        new PatchSetOperation()
+                            .setPath("$.outer.field1")
+                            .setValue(new TextNode("new value"))
+                    ))
+            ))
         );
 
         assertThat(src).hasSameTextualContentAs(
-                Paths.get("src/test/resources/patch/expected-setInJson.json")
+            Paths.get("src/test/resources/patch/expected-setInJson.json")
         );
     }
 

src/test/resources/patch/testing-with-comment.json

@@ -0,0 +1,6 @@
+{
+  "outer": {
+    // some comment
+    "field1": "old"
+  }
+}