From 97bc009cce27e43c901d51ee3d00a2389f64d3d8 Mon Sep 17 00:00:00 2001
From: Mukhtar Haji <mukhtar.haji@oracle.com>
Date: Tue, 6 Jun 2017 11:22:23 +0100
Subject: [PATCH] Revert "Build project/func on host machine for java-maven"

This reverts commit 4ccb8fa33c8a5dc94e7262c3e5595ee4bced3d0b.
---
 fn/langs/base.go       |  6 +++++
 fn/langs/java_maven.go | 54 ++++++++++++++++++++++++++++++++----------
 2 files changed, 47 insertions(+), 13 deletions(-)

diff --git a/fn/langs/base.go b/fn/langs/base.go
index 37b994568..eaf26b782 100644
--- a/fn/langs/base.go
+++ b/fn/langs/base.go
@@ -66,6 +66,7 @@ type LangHelper interface {
 type BaseHelper struct {
 }
 
+<<<<<<< 1918edacff928f017aa215c925d1e454c43f6320
 func (h *BaseHelper) BuildFromImage() string        { return "" }
 func (h *BaseHelper) RunFromImage() string          { return h.BuildFromImage() }
 func (h *BaseHelper) IsMultiStage() bool            { return true }
@@ -78,6 +79,11 @@ func (h *BaseHelper) PreBuild() error               { return nil }
 func (h *BaseHelper) AfterBuild() error             { return nil }
 func (h *BaseHelper) HasBoilerplate() bool          { return false }
 func (h *BaseHelper) GenerateBoilerplate() error    { return nil }
+=======
+func (h *BaseHelper) Cmd() string { return "" }
+func (h *BaseHelper) HasBoilerplate() bool { return false }
+func (h *BaseHelper) GenerateBoilerplate() error { return nil }
+>>>>>>> Revert "Build project/func on host machine for java-maven"
 
 // exists checks if a file exists
 func exists(name string) bool {
diff --git a/fn/langs/java_maven.go b/fn/langs/java_maven.go
index 110adb14a..bf1e9cb47 100644
--- a/fn/langs/java_maven.go
+++ b/fn/langs/java_maven.go
@@ -1,31 +1,59 @@
 package langs
 
-import "fmt"
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+)
 
 // JavaMavenLangHelper provides a set of helper methods for the build lifecycle of Java Maven projects
 type JavaMavenLangHelper struct {
 	BaseHelper
 }
 
+
 // Entrypoint returns the Java runtime Docker entrypoint that will be executed when the function is run
 func (lh *JavaMavenLangHelper) Entrypoint() string {
-	// TODO need mechanism to determine the java user function dynamically
-	userFunction := "com.example.faas.ExampleFunction::itsOn"
-	return fmt.Sprintf("java -jar /function/target/function.jar %s", userFunction)
+	return fmt.Sprintf("java -jar /function/target/function.jar com.example.faas.ExampleFunction::itsOn")
 }
 
-func (lh *JavaMavenLangHelper) HasLocalBuildCmd() bool {
+// HasPreBuild returns whether the Java runtime has a pre-build step
+func (lh *JavaMavenLangHelper) HasPreBuild() bool {
 	return true
 }
 
-func (lh *JavaMavenLangHelper) LocalBuildCmd() []string {
-	return []string{
-		"mvn clean package",
+// PreBuild runs "mvn clean package" in the root of the project and by default expects a jar at `target/function.jar` as the
+// output.  We mount `$HOME/.m2` in order to get maven the proxy config specified in .m2/settings.xml, but it has the nice
+// side effect of making the users .m2/repository available.  Any new deps downloaded will be owned by root :(
+func (lh *JavaMavenLangHelper) PreBuild() error {
+	wd, err := os.Getwd()
+	if err != nil {
+		return err
 	}
+
+	if !exists(filepath.Join(wd, "pom.xml")) {
+		return fmt.Errorf("Could not find pom.xml - are you sure this is a maven project?")
+	}
+
+	cmd := exec.Command(
+		"docker", "run",
+		"--rm",
+		"-v", wd+":/java", "-w", "/java",
+		"-v", os.Getenv("HOME")+"/.m2:/.m2",
+		"maven:3.5-jdk-8-alpine",
+		"/bin/sh", "-c", "mvn -gs /.m2/settings.xml clean package",
+	)
+
+	cmd.Stderr = os.Stderr
+	cmd.Stdout = os.Stdout
+	if err := cmd.Run(); err != nil {
+		return dockerBuildError(err)
+	}
+	return nil
 }
 
-func (lh *JavaMavenLangHelper) HasPreBuild() bool { return false }
-
-func (lh *JavaMavenLangHelper) PreBuild() error { return nil }
-
-func (lh *JavaMavenLangHelper) AfterBuild() error { return nil }
+// AfterBuild should remove the (root-owned) target dir.
+func (lh *JavaMavenLangHelper) AfterBuild() error {
+	return nil
+}