Conversion from YAML to JSON

Add conversion of JSON to YAML, and allow multiple files to be converted with incremental build support.

Resolve castocolina#1

README.md

@@ -1,8 +1,10 @@
 # json2yaml
 
-Gradle plugin for JSON to YAML tranformation
+Gradle plugin for JSON to YAML or YAML to JSON tranformation
 
-### Step 1
+## Basic Usage
+
+### Install the plugin
 
 Apply the plugin
 
@@ -12,11 +14,50 @@ plugins {
 }
 ```
 
-### Step 2
+### Original Tasks (single file conversion)
 
-Set input and output file
+The original plugin version offered a simple model where a single input and output file could be set for conversion.
 
+For JSON to YAML:
 ```
 json2yaml.inputFile = project.file('sample.json')
 json2yaml.outputFile = project.file('output.yaml')
 ```
+
+For YAML to JSON:
+```
+yaml2json.inputFile = project.file('sample.yaml')
+yaml2json.outputFile = project.file('output.json')
+```
+
+### Enhanced Tasks (multiple file conversion)
+
+A newer set of enhanced tasks has been added which allows 
+
+   - multiple files to be converted 
+   - adds support for Gradle incremental builds
+   - allows either a file collection to be supplied, with conversion outputs flattened, or a file tree which preserves the original directory structure
+   - allows file extension mapping to be specified using task configuration options. If the input file extension matches, it  will be swapped with the configured output extension
+
+
+For JSON to YAML - using file collection:
+```
+task incremental(type: dev.castocolina.gradle.plugin.JsonToYaml) {
+    outDir = file("${buildDir}/generated")
+    // collection of files - converted files will appear directly under outDir
+    sourceFiles = layout.files('tst.json', 'src/resources/jsonschema/tst2.json')
+}
+```
+
+For YAML to JSON - using file tree:
+```
+YamlToJson {
+    outDir = file("${buildDir}/generated")
+    // file tree - converted files will use same sub-directory structure as originals
+    sourceFiles = fileTree(dir: "src", include: "resources/jsonschema/*.yaml")
+    // Extension mapping (values shown are actually the defaults). 
+    yamlExt = ".yaml"
+    jsonExt = ".json"
+
+}
+```

build.gradle

@@ -27,13 +27,16 @@ ext {
 }
 
 dependencies {
+    implementation 'org.codehaus.groovy:groovy-all:3.0.5' 
+    implementation 'org.codehaus.groovy:groovy-yaml:3.0.5' 
+
     implementation "com.fasterxml.jackson.dataformat:jackson-dataformat-yaml:${jacksonVer}"
     implementation "com.fasterxml.jackson.datatype:jackson-datatype-jsr310:${jacksonVer}"
     // Use the awesome Spock testing and specification framework
     testImplementation 'org.spockframework:spock-core:1.3-groovy-2.5'
 }
 
-version = "1.0.0-SNAPSHOT"
+version = "1.1.0-SNAPSHOT"
 
 pluginBundle {
     website = 'https://github.com/castocolina/json2yaml' 

src/main/groovy/dev/castocolina/gradle/plugin/Json2YamlPlugin.groovy

@@ -1,5 +1,7 @@
 /*
- * This Groovy source file was generated by the Gradle 'init' task.
+ * Various flavours of JSON <> YAML converstion task
+ * Note: I am definitely more of a Java coder than a Groovy one, and also on something of a Gradle learning process here
+ *       So feel free to critique and suggest improvements!
  */
 package dev.castocolina.gradle.plugin
 
@@ -10,30 +12,50 @@ import com.fasterxml.jackson.databind.ObjectMapper
 import com.fasterxml.jackson.dataformat.yaml.YAMLFactory
 import com.fasterxml.jackson.dataformat.yaml.YAMLGenerator.Feature
 
+import groovy.yaml.YamlSlurper
+import com.fasterxml.jackson.core.JsonFactory
+
+import org.gradle.api.file.FileCollection
+import org.gradle.api.file.FileTree
+import org.gradle.api.DefaultTask
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.InputFiles
+import org.gradle.api.tasks.Internal
+import org.gradle.api.tasks.OutputDirectory
+import org.gradle.api.tasks.TaskAction
+import org.gradle.api.tasks.SkipWhenEmpty
+import org.gradle.api.tasks.incremental.IncrementalTaskInputs
+
 public class Json2YamlPluginExtension {
     File inputFile = new File('sample.json')
     File outputFile = new File('build/tmp/docs.yaml')
     Boolean minimizeQuote = Boolean.TRUE
     Boolean deleteTargetFirst = Boolean.TRUE
 }
 
+public class Yaml2JsonPluginExtension {
+    File inputFile = new File('sample.yaml')
+    File outputFile = new File('build/tmp/docs.json')
+    Boolean deleteTargetFirst = Boolean.TRUE
+}
+
 /**
- * A simple 'hello world' plugin.
+ * Main class to register plugin tasks
  */
 public class Json2YamlPlugin implements Plugin<Project> {
     public void apply(Project project) {
-        def extension = project.extensions.create('json2yaml', Json2YamlPluginExtension)
 
-        // Register a task
+        // Register task from JSON to YAML - from code originally forked
+        def extToJson = project.extensions.create('json2yaml', Json2YamlPluginExtension)
 
         project.tasks.register("json2yaml") {
             def inJson, ouYaml, minQuote, delTarget
 
             doFirst {
-                inJson = extension.inputFile
-                ouYaml = extension.outputFile
-                minQuote = extension.minimizeQuote
-                delTarget = extension.deleteTargetFirst
+                inJson = extToJson.inputFile
+                ouYaml = extToJson.outputFile
+                minQuote = extToJson.minimizeQuote
+                delTarget = extToJson.deleteTargetFirst
 
                 println "Transform input: " + inJson.absolutePath
                 println "Transform output: " + ouYaml.absolutePath
@@ -43,17 +65,146 @@ public class Json2YamlPlugin implements Plugin<Project> {
             }
 
             doLast {
-                def jsonText = inJson.text
-                def jSonMap = new JsonSlurper().parseText(jsonText)
-                def factory = new YAMLFactory()
-                if (minQuote){
-                    factory.enable(Feature.MINIMIZE_QUOTES)
+                JsonToYaml.doIt(inJson, ouYaml, minQuote)
+                println("File converted!!!")
+            }
+
+        }
+
+        // Register task from YAML to JSON - following same approach as code originally forked
+        def extToYaml = project.extensions.create('yaml2json', Yaml2JsonPluginExtension)
+
+        project.tasks.register("yaml2json") {
+            def inYaml, ouJson, delTarget
+
+            doFirst {
+                inYaml = extToYaml.inputFile
+                ouJson = extToYaml.outputFile
+                delTarget = extToYaml.deleteTargetFirst
+
+                println "Transform input: " + inYaml.absolutePath
+                println "Transform output: " + ouJson.absolutePath
+                if (delTarget){
+                    println "Delete target first: " + ouJson.delete()
                 }
-                def mapper = new ObjectMapper(factory)
-                mapper.writeValue(ouYaml, jSonMap)
+            }
+
+            doLast {
+                YamlToJson.doIt(inYaml, ouJson)
                 println("File converted!!!")
             }
 
         }
+
+        // Alternate approach to register custom tasks for converrsion. This allows use of the 
+        // injection of config properties and support for incremental build handling
+        project.tasks.register("JsonToYaml", JsonToYaml)        
+        project.tasks.register("YamlToJson", YamlToJson)
     }
 }
+
+// Newer classes to provide conversion tasks with incremental build support
+
+public abstract class ConverterTask extends DefaultTask {
+    @OutputDirectory
+    File outDir = project.file("${project.buildDir}/generated")
+
+    @InputFiles
+    @SkipWhenEmpty
+    FileCollection sourceFiles
+
+    @Input
+    String yamlExt = ".yaml"    // configurable default extension for YAML files
+
+    @Input
+    String jsonExt = ".json"    // configurable default extension for JSON files
+
+
+    @Internal
+    def convertMap = [:]
+
+    void initConversionMap(String extFrom, String extTo) {
+        if (sourceFiles instanceof FileTree) {
+            // For file trees, we will try and preserve structure on output
+            FileTree tree = (FileTree) sourceFiles
+            tree.visit {element ->
+                if (element.file.isFile()) {
+                    convertMap.put(element.file, swapExtension(element.relativePath.toString(), extFrom, extTo))
+                }
+            }
+        } else {
+            // For simple collections, output will be flattened
+            sourceFiles.each {File file ->
+                if (file.isFile()) {
+                    convertMap.put(file, swapExtension(file.name, extFrom, extTo))
+                }
+            }
+        } 
+    }
+
+    String swapExtension(String path, String extFrom, String extTo) {
+        return (path.endsWith(extFrom)) ? path.take(path.lastIndexOf('.')) + extTo
+                                        : path + extTo
+    }
+
+    void convertAll() {
+        convertMap.each{entry -> convert(entry.key, new File(outDir, entry.value))}
+    }
+
+    abstract void convert(File fin, File fout)
+}
+
+public class YamlToJson extends ConverterTask {
+
+    @TaskAction
+    void perform() {
+        initConversionMap(yamlExt, jsonExt)
+        convertAll()
+    }
+
+    void convert(File fin, File fout) {
+        doIt(fin, fout)
+    }
+
+    static void doIt (File fin, File fout) {
+        def yamlText = fin.text
+        def yamlMap = new YamlSlurper().parseText(yamlText)
+        def factory = new JsonFactory()
+        def mapper = new ObjectMapper(factory)
+
+        fout.parentFile.mkdirs()
+        mapper.writeValue(fout, yamlMap)
+    }
+}
+
+
+public class JsonToYaml extends ConverterTask {
+
+    @Input
+    boolean minimizeQuote = true
+
+    @TaskAction
+    void perform() {
+        initConversionMap(jsonExt, yamlExt)
+        convertAll()
+    }
+
+    void convert(File fin, File fout) {
+        doIt(fin, fout, minimizeQuote)
+    }
+
+    static void doIt (File fin, File fout, boolean minQuote) {
+        def jsonText = fin.text
+        def jSonMap = new JsonSlurper().parseText(jsonText)
+        def factory = new YAMLFactory()
+        if (minQuote){
+             factory.enable(Feature.MINIMIZE_QUOTES)
+         }
+        def mapper = new ObjectMapper(factory)
+
+        fout.parentFile.mkdirs()
+        mapper.writeValue(fout, jSonMap)
+    }
+}
+
+

src/test/groovy/dev/castocolina/gradle/plugin/Json2YamlPluginTest.groovy

@@ -19,7 +19,9 @@ public class Json2YamlPluginTest extends Specification {
         project.plugins.apply("dev.castocolina.json2yaml")
 
         then:
-        project.tasks.findByName("json2yaml") != null
-
+        (project.tasks.findByName("json2yaml") != null &&
+         project.tasks.findByName("yaml2json") != null &&
+         project.tasks.findByName("JsonToYaml") != null &&
+         project.tasks.findByName("YamlToJson") != null)
     }
 }