Move proto compilation to RuleBuilder

Using blueprint.Rule for protoc commands was causing code duplication
because there was no good way to run the same protoc for cc, java and
python but then run custom source packaging steps for java and python.
Move most of the code into a common function that returns a
RuleBuilder, and then let java and python add their own commands at
the end of the rule.

Bug: 70706119
Test: All Soong tests
Test: m checkbuild
Change-Id: Ic692136775d273bcc4f4de99620ab4878667c83a

2 files changed, 25 insertions, 46 deletions

diff --git a/python/proto.go b/python/proto.go
index 2370cd26..813e91dd 100644
--- a/python/proto.go
+++ b/python/proto.go
@@ -16,58 +16,35 @@ package python
 
 import (
 	"android/soong/android"
-	"strings"
-
-	"github.com/google/blueprint"
 )
 
-func init() {
-	pctx.HostBinToolVariable("protocCmd", "aprotoc")
-}
+func genProto(ctx android.ModuleContext, protoFile android.Path, flags android.ProtoFlags, pkgPath string) android.Path {
+	srcsZipFile := android.PathForModuleGen(ctx, protoFile.Base()+".srcszip")
 
-var (
-	proto = pctx.AndroidStaticRule("protoc",
-		blueprint.RuleParams{
-			Command: `rm -rf $out.tmp && mkdir -p $out.tmp && ` +
-				`$protocCmd --python_out=$out.tmp --dependency_out=$out.d -I $protoBase $protoFlags $in && ` +
-				`$parCmd -o $out $pkgPathArgs -C $out.tmp -D $out.tmp && rm -rf $out.tmp`,
-			CommandDeps: []string{
-				"$protocCmd",
-				"$parCmd",
-			},
-			Depfile: "${out}.d",
-			Deps:    blueprint.DepsGCC,
-		}, "protoBase", "protoFlags", "pkgPathArgs")
-)
+	outDir := srcsZipFile.ReplaceExtension(ctx, "tmp")
+	depFile := srcsZipFile.ReplaceExtension(ctx, "srcszip.d")
 
-func genProto(ctx android.ModuleContext, p *android.ProtoProperties,
-	protoFile android.Path, protoFlags []string, pkgPath string) android.Path {
-	srcJarFile := android.PathForModuleGen(ctx, protoFile.Base()+".srcszip")
+	rule := android.NewRuleBuilder()
 
-	protoRoot := android.ProtoCanonicalPathFromRoot(ctx, p)
+	rule.Command().Text("rm -rf").Flag(outDir.String())
+	rule.Command().Text("mkdir -p").Flag(outDir.String())
 
-	var protoBase string
-	if protoRoot {
-		protoBase = "."
-	} else {
-		protoBase = strings.TrimSuffix(protoFile.String(), protoFile.Rel())
-	}
+	android.ProtoRule(ctx, rule, protoFile, flags, nil, outDir, depFile, nil)
 
-	var pkgPathArgs string
+	// Proto generated python files have an unknown package name in the path, so package the entire output directory
+	// into a srcszip.
+	zipCmd := rule.Command().
+		Tool(ctx.Config().HostToolPath(ctx, "soong_zip")).
+		FlagWithOutput("-o ", srcsZipFile).
+		FlagWithArg("-C ", outDir.String()).
+		FlagWithArg("-D ", outDir.String())
 	if pkgPath != "" {
-		pkgPathArgs = "-P " + pkgPath
+		zipCmd.FlagWithArg("-P ", pkgPath)
 	}
-	ctx.Build(pctx, android.BuildParams{
-		Rule:        proto,
-		Description: "protoc " + protoFile.Rel(),
-		Output:      srcJarFile,
-		Input:       protoFile,
-		Args: map[string]string{
-			"protoBase":   protoBase,
-			"protoFlags":  strings.Join(protoFlags, " "),
-			"pkgPathArgs": pkgPathArgs,
-		},
-	})
 
-	return srcJarFile
+	rule.Command().Text("rm -rf").Flag(outDir.String())
+
+	rule.Build(pctx, ctx, "protoc_"+protoFile.Rel(), "protoc "+protoFile.Rel())
+
+	return srcsZipFile
 }
diff --git a/python/python.go b/python/python.go
index 6eb9b6ef..3c3c396a 100644
--- a/python/python.go
+++ b/python/python.go
@@ -516,9 +516,11 @@ func (p *Module) createSrcsZip(ctx android.ModuleContext, pkgPath string) androi
 	}
 	var zips android.Paths
 	if len(protoSrcs) > 0 {
+		protoFlags := android.GetProtoFlags(ctx, &p.protoProperties)
+		protoFlags.OutTypeFlag = "--python_out"
+
 		for _, srcFile := range protoSrcs {
-			zip := genProto(ctx, &p.protoProperties, srcFile,
-				android.ProtoFlags(ctx, &p.protoProperties), pkgPath)
+			zip := genProto(ctx, srcFile, protoFlags, pkgPath)
 			zips = append(zips, zip)
 		}
 	}