Pagination attempts (#5)

* Adds pagination example

README.md

@@ -13,29 +13,37 @@ You can find :
 * [SwaCLIBasic](src/main/kotlin/nl/lengrand/swacli/SwaCLIBasic.kt) Not doing anything but showing how picoCLI comes with batteries included
 * [SwaCLIOptions](src/main/kotlin/nl/lengrand/swacli/SwaCLIOptions.kt) A small demonstration on how to use (mutually exclusive) options and arguments
 * [SwaCLISubCommands](src/main/kotlin/nl/lengrand/swacli/SwaCLISubCommands.kt) A small demonstration on how to use subcommands 
+* [SwaCLIPaginate](src/main/kotlin/nl/lengrand/swacli/SwaCLIPaginate.kt) A small demonstration on how to use subcommands and paginate the results. Default command in the sw compilable
 * [SwaCLIProgrammatic](src/main/kotlin/nl/lengrand/swacli/SwaCLIProgrammatic.kt) An example that uses the programmatic API instead of the annotation system.
 * [SwaCLISubCommandsTest](src/test/kotlin/nl/lengrand/swacli/SwaCLISubCommandsTest.kt) An example on how to test commandline configurations 
 
 
 All examples are in Kotlin and provide the same rough capabilities (get some facts about characters or planets in Star Wars)
 
-## Running
+## Compiling / Running 
 
 ```
 $  ./gradlew customFatJar
-$ java -cp build/libs/all-in-one-jar-1.0-SNAPSHOT.jar nl.lengrand.swacli.SwaCLI
-# to keep color and paginate the results
-$ java -Dpicocli.ansi=true -cp build/libs/all-in-one-jar-1.0-SNAPSHOT.jar nl.lengrand.swacli.SwaCLIOptions -p | less -R 
-# to create the native image
-$ cd build/libs;native-image --static -jar all-in-one-jar-1.0-SNAPSHOT.jar sw
+$ java -cp build/libs/all-in-one-jar-1.0-SNAPSHOT.jar nl.lengrand.swacli.SwaCLIPaginate
+```
+
+or if you're on Mac give a shot to the latest [release](https://github.com/jlengrand/swacli/releases).
+
+## Creating the native image
+
+[You'll need to have GraalVM and the native image extension setup on your system :)](https://www.graalvm.org/reference-manual/native-image/)
+
+```
+$ cd build/libs;native-image --static -jar all-in-one-jar-1.0-SNAPSHOT.jar sw --enable-http --enable-https
 # remove static if you're on Mac :)
-$ cd build/libs;native-image -jar all-in-one-jar-1.0-SNAPSHOT.jar sw
 ```
 
 ##  Why
 
 This is an example CLI that I created as illustration for my [JFall 2020 talk](https://jfall.nl/sessions/an-introduction-to-creating-cli-applications-using-picocli/)
 
+You can check out the slides [here](https://github.com/jlengrand/picocli-jfall-bitesize-2020). 
+
 ## Source
 
 * [The repository can be found here](https://github.com/jlengrand/swacli)

build.gradle

@@ -49,7 +49,7 @@ kapt {
 
 task customFatJar(type: Jar) {
     manifest {
-        attributes 'Main-Class': 'nl.lengrand.swacli.SwaCLISubCommands'
+        attributes 'Main-Class': 'nl.lengrand.swacli.SwaCLIPaginate'
     }
     baseName = 'all-in-one-jar'
     from { configurations.runtimeClasspath.collect { it.isDirectory() ? it : zipTree(it) } }

src/main/kotlin/nl/lengrand/swacli/PrettyPrinter.kt

@@ -12,7 +12,7 @@ ______     __     __     ______     ______     __         __
   \/_____/   \/_/   \/_/   \/_/\/_/   \/_____/   \/_____/   \/_/
 """
 
-class PrettyPrinter(val spec : CommandLine.Model.CommandSpec ) {
+class PrettyPrinter(val spec : CommandLine.Model.CommandSpec) {
     fun <T : Data> print(response: Response<T>){
 
         spec.commandLine().out.println("""

src/main/kotlin/nl/lengrand/swacli/SwaCLIPaginate.kt

@@ -0,0 +1,55 @@
+package nl.lengrand.swacli
+
+import picocli.CommandLine
+import picocli.CommandLine.*
+import picocli.CommandLine.Model.*
+import java.io.FileWriter
+import java.io.PrintWriter
+import java.nio.file.Files
+import java.util.concurrent.Callable
+import kotlin.system.exitProcess
+
+@Command(
+    name = "sw",
+    version = ["0.2"],
+    mixinStandardHelpOptions = true,
+    description = [asciiArt, "@|bold,yellow \uD83E\uDE90 A Star Wars CLI built on top of https://swapi.dev/ \uD83E\uDE90 |@"],
+    subcommands = [PlanetsCommand::class, PeopleCommand::class, HelpCommand::class]
+)
+class SwaCLIPaginate : Callable<Int> {
+
+    @Spec
+    lateinit var spec: CommandSpec
+
+    private fun executionStrategy(parseResult: ParseResult): Int {
+
+        if (!parseResult.hasSubcommand())
+            return RunLast().execute(parseResult)
+
+        val file = Files.createTempFile("pico", ".tmp").toFile()
+        this.spec.commandLine().out = PrintWriter(FileWriter(file), true)
+
+        val result = RunLast().execute(parseResult)
+
+        val processBuilder = ProcessBuilder("less", file.absolutePath).inheritIO()
+        val process = processBuilder.start()
+        process.waitFor()
+
+        return result
+    }
+
+    override fun call(): Int {
+        spec.commandLine().usage(System.out)
+        return 0
+    }
+
+    companion object{
+        @JvmStatic
+        fun main(args: Array<String>){
+            val app = SwaCLIPaginate()
+            exitProcess(CommandLine(app)
+                    .setExecutionStrategy(app::executionStrategy)
+                    .execute(*args))
+        }
+    }
+}