Update build configurations to use Go modules. (#142)

* Update build configurations to use Go modules.

* Remove unneeded proto compilation options.

* Full go get (./...) for all nested projects.

COMPILE-PROTOS.sh

@@ -17,26 +17,9 @@
 
 go get github.com/golang/protobuf/protoc-gen-go
 
-protoc \
---go_out=Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. \
-OpenAPIv2/OpenAPIv2.proto
-
-protoc \
---go_out=Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. \
-OpenAPIv3/OpenAPIv3.proto
-
-protoc \
---go_out=Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. \
-discovery/discovery.proto
-
-protoc \
---go_out=Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. \
-plugins/plugin.proto
-
-protoc \
---go_out=Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. \
-extensions/extension.proto
-
-protoc \
---go_out=Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. \
-surface/surface.proto
+protoc --go_out=. OpenAPIv2/OpenAPIv2.proto
+protoc --go_out=. OpenAPIv3/OpenAPIv3.proto
+protoc --go_out=. discovery/discovery.proto
+protoc --go_out=. plugins/plugin.proto
+protoc --go_out=. extensions/extension.proto
+protoc --go_out=. surface/surface.proto

Makefile

@@ -1,13 +1,7 @@
 
 build:
 	./COMPILE-PROTOS.sh
-	go get
-	go install
-	cd generate-gnostic; go get; go install
-	cd apps/disco; go get; go install
-	cd apps/report; go get; go install
-	cd apps/petstore-builder; go get; go install
-	cd plugins/gnostic-summary; go get; go install
-	cd plugins/gnostic-analyze; go get; go install
+	go get ./...
+	go install ./...
 	cd extensions/sample; make
 

README.md

@@ -44,9 +44,14 @@ and the [Google Protocol Buffer Compiler](https://github.com/google/protobuf).
 
 ## Installation
 
-1. Get this package by downloading it with `go get`.
+The following instructions are for installing gnostic using
+[Go modules](https://blog.golang.org/using-go-modules),
+supported by Go 1.11 and later.
 
-        go get github.com/googleapis/gnostic
+1. Get this package by downloading it with `git clone`.
+
+        git clone https://github.com/googleapis/gnostic
+        cd gnostic
 
 2. [Optional] Build and run the gnostic compiler generator. 
 This uses JSON schemas to generate Protocol Buffer language files
@@ -57,9 +62,7 @@ the generated protocol buffer models.
 Pre-generated versions of these files are checked into the directories
 named OpenAPIv2, OpenAPIv3, and discovery.
 
-        cd $GOPATH/src/github.com/googleapis/gnostic/generate-gnostic
-        go install
-        cd ..
+        go install ./generate-gnostic
         generate-gnostic --v2
         generate-gnostic --v3
         generate-gnostic --discovery
@@ -70,15 +73,15 @@ and the Go protoc plugin.
 You can get protoc [here](https://github.com/google/protobuf).
 You can install the plugin with this command:
 
-        go get -u github.com/golang/protobuf/protoc-gen-go
+        go get github.com/golang/protobuf/protoc-gen-go
 
-Then use the following to compile the Gnostic Protocol Buffer models:
+Then use the following to compile the gnostic Protocol Buffer models:
 
         ./COMPILE-PROTOS.sh
 
 4. Build **gnostic**. 
 
-        go install github.com/googleapis/gnostic
+        go install .
 
 5. Run **gnostic**. This sample invocation creates a file in the current directory named "petstore.pb" that contains a binary
 Protocol Buffer description of a sample API.
@@ -93,7 +96,7 @@ Protocol Buffer description. This is mainly for use in testing and debugging.
 
 7. For a sample application, see apps/report.
 
-        go install github.com/googleapis/gnostic/apps/report
+        go install ./apps/report
         report petstore.pb
 
 8. **gnostic** supports plugins. Some are already implemented in the `plugins` directory.

extensions/sample/Makefile

@@ -1,10 +1,8 @@
 
 build:
-	go get github.com/golang/protobuf/protoc-gen-go
-	cd ..; ./COMPILE-EXTENSION.sh
-	generate-gnostic --extension x-sampleone.json --out_dir=$(GOPATH)/src/github.com/googleapis/gnostic/extensions/sample/generated
-	cd generated/gnostic-x-sampleone/proto; protoc --go_out=Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. *.proto
+	generate-gnostic --extension x-sampleone.json --out_dir=generated
+	cd generated/gnostic-x-sampleone/proto; protoc --go_out=. *.proto
 	cd generated/gnostic-x-sampleone; go get; go install
-	generate-gnostic --extension x-sampletwo.json --out_dir=$(GOPATH)/src/github.com/googleapis/gnostic/extensions/sample/generated
-	cd generated/gnostic-x-sampletwo/proto; protoc --go_out=Mgoogle/protobuf/any.proto=github.com/golang/protobuf/ptypes/any:. *.proto
+	generate-gnostic --extension x-sampletwo.json --out_dir=generated
+	cd generated/gnostic-x-sampletwo/proto; protoc --go_out=. *.proto
 	cd generated/gnostic-x-sampletwo; go get; go install

generate-gnostic/generate-extension.go

@@ -273,7 +273,11 @@ func GenerateExtension(schemaFile string, outDir string) error {
 	err = exec.Command(runtime.GOROOT()+"/bin/gofmt", "-w", goFilename).Run()
 
 	// generate the main file.
-	outDirRelativeToGoPathSrc := strings.Replace(outDir, path.Join(os.Getenv("GOPATH"), "src")+"/", "", 1)
+
+	// TODO: This path is currently fixed to the location of the samples.
+	//       Can we make it relative, perhaps with an option or by generating
+	//       a go.mod file for the generated extension handler?
+	outDirRelativeToPackageRoot := "github.com/googleapis/gnostic/extensions/sample/" + outDir
 
 	var extensionNameKeys []string
 	for k := range extensionNameToMessageName {
@@ -298,7 +302,7 @@ func GenerateExtension(schemaFile string, outDir string) error {
 		"github.com/googleapis/gnostic/extensions",
 		"github.com/googleapis/gnostic/compiler",
 		"gopkg.in/yaml.v2",
-		outDirRelativeToGoPathSrc + "/" + "proto",
+		outDirRelativeToPackageRoot + "/" + "proto",
 	}
 	if wrapperTypeIncluded {
 		imports = append(imports, "github.com/golang/protobuf/ptypes/wrappers")

go.mod

@@ -0,0 +1,9 @@
+module github.com/googleapis/gnostic
+
+go 1.12
+
+require (
+	github.com/docopt/docopt-go v0.0.0-20180111231733-ee0de3bc6815
+	github.com/golang/protobuf v1.3.2
+	gopkg.in/yaml.v2 v2.2.2
+)

go.sum

@@ -0,0 +1,7 @@
+github.com/docopt/docopt-go v0.0.0-20180111231733-ee0de3bc6815 h1:bWDMxwH3px2JBh6AyO7hdCn/PkvCZXii8TGj7sbtEbQ=
+github.com/docopt/docopt-go v0.0.0-20180111231733-ee0de3bc6815/go.mod h1:WwZ+bS3ebgob9U8Nd0kOddGdZWjyMGR8Wziv+TBNwSE=
+github.com/golang/protobuf v1.3.2 h1:6nsPYzhq5kReh6QImI3k5qWzO4PEbvbIW2cwSfR/6xs=
+github.com/golang/protobuf v1.3.2/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=