Uses a real go project to showcase vendor example so glide works (#828)

2018-08-01 23:55:54 +08:00
parent 6123873d2a
commit 4356378301
36 changed files with 6530 additions and 7 deletions
@@ -1,12 +1,13 @@
 package main

 import (
-	"go/vendordir/test"
 	"net/http"
+
+	"github.com/golang/example/stringutil"
 )

 // Handler is the entry point for this fission function
 func Handler(w http.ResponseWriter, r *http.Request) {
-	msg := test.Test()
+	msg := stringutil.Reverse(stringutil.Reverse("Vendor Example Test"))
 	w.Write([]byte(msg))
 }
@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
@@ -0,0 +1,65 @@
+# Go example projects
+
+This repository contains a collection of Go programs and libraries that
+demonstrate the language, standard libraries, and tools.
+
+## The examples
+
+### [hello](hello/) ([godoc](//godoc.org/github.com/golang/example/hello)) and [stringutil](stringutil/) ([godoc](//godoc.org/github.com/golang/example/stringutil))
+
+    go get github.com/golang/example/hello
+
+A trivial "Hello, world" program that uses a stringutil package.
+
+Command [hello](hello/) covers:
+
+* The basic form of an executable command
+* Importing packages (from the standard library and the local repository)
+* Printing strings ([fmt](//golang.org/pkg/fmt/))
+
+Library [stringutil](stringutil/) covers:
+
+* The basic form of a library
+* Conversion between string and []rune
+* Table-driven unit tests ([testing](//golang.org/pkg/testing/))
+
+### [outyet](outyet/) ([godoc](//godoc.org/github.com/golang/example/outyet))
+
+    go get github.com/golang/example/outyet
+
+A web server that answers the question: "Is Go 1.x out yet?"
+
+Topics covered:
+
+* Command-line flags ([flag](//golang.org/pkg/flag/))
+* Web servers ([net/http](//golang.org/pkg/net/http/))
+* HTML Templates ([html/template](//golang.org/pkg/html/template/))
+* Logging ([log](//golang.org/pkg/log/))
+* Long-running background processes
+* Synchronizing data access between goroutines ([sync](//golang.org/pkg/sync/))
+* Exporting server state for monitoring ([expvar](//golang.org/pkg/expvar/))
+* Unit and integration tests ([testing](//golang.org/pkg/testing/))
+* Dependency injection
+* Time ([time](//golang.org/pkg/time/))
+
+### [appengine-hello](appengine-hello/) ([godoc](//godoc.org/github.com/golang/example/appengine-hello))
+
+	goapp get github.com/golang/example/appengine-hello
+
+A trivial "Hello, world" App Engine application intended to be used as the
+starting point for your own code.
+
+_Note_: The `goapp` tool is part of the [Google App Engine SDK for Go](https://cloud.google.com/appengine/downloads#Google_App_Engine_SDK_for_Go).
+
+### [gotypes](gotypes/) ([godoc](//godoc.org/github.com/golang/example/gotypes))
+
+The `go/types` package is a type-checker for Go programs. It is one of the most
+complex packages in Go's standard library, so we have provided this tutorial to
+help you find your bearings. It comes with several example programs that you
+can obtain using `go get` and play with as you learn to build tools that analyze
+or manipulate Go programs.
+
+### [template](template/) ([godoc](//godoc.org/github.com/golang/example/template))
+
+A trivial web server that demonstrates the use of the
+[`template` package](https://golang.org/pkg/text/template/)'s `block` feature.
@@ -0,0 +1,11 @@
+This code is a starting point for your Google App Engine application in
+Go.
+
+To run the application locally you need the install the [Go Cloud
+SDK](https://cloud.google.com/appengine/docs/go/#Go_tools) and execute the next
+command from the directory containing this file:
+
+    $ goapp serve app.yaml
+
+To deploy the application you have to first create an App Engine project
+and use it as the application file in all the yaml files.
@@ -0,0 +1,32 @@
+// Copyright 2015 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package hello is a simple App Engine application that replies to requests
+// on /hello with a welcoming message.
+package hello
+
+import (
+	"fmt"
+	"net/http"
+)
+
+// init is run before the application starts serving.
+func init() {
+	// Handle all requests with path /hello with the helloHandler function.
+	http.HandleFunc("/hello", helloHandler)
+}
+
+func helloHandler(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintln(w, "Hello from the Go app")
+}
@@ -0,0 +1,32 @@
+# Copyright 2015 Google Inc. All rights reserved.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+# http:#www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to writing, software distributed
+# under the License is distributed on a "AS IS" BASIS, WITHOUT WARRANTIES OR
+# CONDITIONS OF ANY KIND, either express or implied.
+
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+application: you-application-id
+version: 1
+runtime: go
+api_version: go1
+
+handlers:
+- url: /hello
+  script: _go_app
+
+- url: /favicon.ico
+  static_files: static/favicon.ico
+  upload: static/favicon.ico
+
+- url: /
+  static_files: static/index.html
+  upload: static/index.html
+
+- url: /
+  static_dir: static
@@ -0,0 +1,34 @@
+<!DOCTYPE html>
+
+<!--
+Copyright 2015 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+<html>
+
+<head>
+    <title>Hello, world</title>
+    <link rel="stylesheet" href="/style.css">
+    <script src="/script.js"></script>
+</head>
+
+<body>
+    <h1>Hello, world</h1>
+
+    <button onclick="fetchMessage()">Fetch Message</button>
+    <p id="message">Click on the button to fetch the message.</p>
+</body>
+
+</html>
@@ -0,0 +1,24 @@
+/*
+Copyright 2015 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+"use strict";
+
+function fetchMessage() {
+    var xmlHttp = new XMLHttpRequest();
+    xmlHttp.open("GET", "/hello", false);
+    xmlHttp.send(null);
+    document.getElementById("message").innerHTML = xmlHttp.responseText;
+}
@@ -0,0 +1,19 @@
+/*
+Copyright 2015 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+h1 {
+  text-align: center;
+}
@@ -0,0 +1,13 @@
+
+all: README.md
+	go build ./...
+
+README.md: go-types.md weave.go $(wildcard */*.go)
+	go run weave.go go-types.md >README.md
+
+# This is for previewing using github.
+# $HOME/markdown must be a github client.
+test: README.md
+	cp README.md $$HOME/markdown/
+	(cd $$HOME/markdown/ && git commit -m . README.md && git push)
+
@@ -0,0 +1,68 @@
+package main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/importer"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"log"
+)
+
+const hello = `package main
+
+import "fmt"
+
+func main() {
+        fmt.Println("Hello, world")
+}
+`
+
+//!+
+func PrintDefsUses(fset *token.FileSet, files ...*ast.File) error {
+	conf := types.Config{Importer: importer.Default()}
+	info := &types.Info{
+		Defs: make(map[*ast.Ident]types.Object),
+		Uses: make(map[*ast.Ident]types.Object),
+	}
+	_, err := conf.Check("hello", fset, files, info)
+	if err != nil {
+		return err // type error
+	}
+
+	for id, obj := range info.Defs {
+		fmt.Printf("%s: %q defines %v\n",
+			fset.Position(id.Pos()), id.Name, obj)
+	}
+	for id, obj := range info.Uses {
+		fmt.Printf("%s: %q uses %v\n",
+			fset.Position(id.Pos()), id.Name, obj)
+	}
+	return nil
+}
+
+//!-
+
+func main() {
+	// Parse one file.
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "hello.go", hello, 0)
+	if err != nil {
+		log.Fatal(err) // parse error
+	}
+	if err := PrintDefsUses(fset, f); err != nil {
+		log.Fatal(err) // type error
+	}
+}
+
+/*
+//!+output
+$ go build github.com/golang/example/gotypes/defsuses
+$ ./defsuses
+hello.go:1:9: "main" defines <nil>
+hello.go:5:6: "main" defines func hello.main()
+hello.go:6:9: "fmt" uses package fmt
+hello.go:6:13: "Println" uses func fmt.Println(a ...interface{}) (n int, err error)
+//!-output
+*/
@@ -0,0 +1,77 @@
+// The doc command prints the doc comment of a package-level object.
+package main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"log"
+	"os"
+
+	// TODO: these will use std go/types after Feb 2016
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/types/typeutil"
+)
+
+func main() {
+	if len(os.Args) != 3 {
+		log.Fatal("Usage: doc <package> <object>")
+	}
+	//!+part1
+	pkgpath, name := os.Args[1], os.Args[2]
+
+	// The loader loads a complete Go program from source code.
+	conf := loader.Config{ParserMode: parser.ParseComments}
+	conf.Import(pkgpath)
+	lprog, err := conf.Load()
+	if err != nil {
+		log.Fatal(err) // load error
+	}
+
+	// Find the package and package-level object.
+	pkg := lprog.Package(pkgpath).Pkg
+	obj := pkg.Scope().Lookup(name)
+	if obj == nil {
+		log.Fatalf("%s.%s not found", pkg.Path(), name)
+	}
+	//!-part1
+	//!+part2
+
+	// Print the object and its methods (incl. location of definition).
+	fmt.Println(obj)
+	for _, sel := range typeutil.IntuitiveMethodSet(obj.Type(), nil) {
+		fmt.Printf("%s: %s\n", lprog.Fset.Position(sel.Obj().Pos()), sel)
+	}
+
+	// Find the path from the root of the AST to the object's position.
+	// Walk up to the enclosing ast.Decl for the doc comment.
+	_, path, _ := lprog.PathEnclosingInterval(obj.Pos(), obj.Pos())
+	for _, n := range path {
+		switch n := n.(type) {
+		case *ast.GenDecl:
+			fmt.Println("\n", n.Doc.Text())
+			return
+		case *ast.FuncDecl:
+			fmt.Println("\n", n.Doc.Text())
+			return
+		}
+	}
+	//!-part2
+}
+
+/*
+//!+output
+$ ./doc net/http File
+type net/http.File interface{Readdir(count int) ([]os.FileInfo, error); Seek(offset int64, whence int) (int64, error); Stat() (os.FileInfo, error); io.Closer; io.Reader}
+/go/src/io/io.go:92:2: method (net/http.File) Close() error
+/go/src/io/io.go:71:2: method (net/http.File) Read(p []byte) (n int, err error)
+/go/src/net/http/fs.go:65:2: method (net/http.File) Readdir(count int) ([]os.FileInfo, error)
+/go/src/net/http/fs.go:66:2: method (net/http.File) Seek(offset int64, whence int) (int64, error)
+/go/src/net/http/fs.go:67:2: method (net/http.File) Stat() (os.FileInfo, error)
+
+ A File is returned by a FileSystem's Open method and can be
+served by the FileServer implementation.
+
+The methods should behave the same as those on an *os.File.
+//!-output
+*/
@@ -0,0 +1,10 @@
+//!+
+package main
+
+import "fmt"
+
+func main() {
+	fmt.Println("Hello, 世界")
+}
+
+//!-
@@ -0,0 +1,81 @@
+// The hugeparam command identifies by-value parameters that are larger than n bytes.
+//
+// Example:
+//	$ ./hugeparams encoding/xml
+package main
+
+import (
+	"flag"
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"log"
+
+	"golang.org/x/tools/go/loader"
+)
+
+//!+
+var bytesFlag = flag.Int("bytes", 48, "maximum parameter size in bytes")
+
+var sizeof = (&types.StdSizes{8, 8}).Sizeof // the sizeof function
+
+func PrintHugeParams(fset *token.FileSet, info *types.Info, files []*ast.File) {
+	checkTuple := func(descr string, tuple *types.Tuple) {
+		for i := 0; i < tuple.Len(); i++ {
+			v := tuple.At(i)
+			if sz := sizeof(v.Type()); sz > int64(*bytesFlag) {
+				fmt.Printf("%s: %q %s: %s = %d bytes\n",
+					fset.Position(v.Pos()),
+					v.Name(), descr, v.Type(), sz)
+			}
+		}
+	}
+	checkSig := func(sig *types.Signature) {
+		checkTuple("parameter", sig.Params())
+		checkTuple("result", sig.Results())
+	}
+	for _, file := range files {
+		ast.Inspect(file, func(n ast.Node) bool {
+			switch n := n.(type) {
+			case *ast.FuncDecl:
+				checkSig(info.Defs[n.Name].Type().(*types.Signature))
+			case *ast.FuncLit:
+				checkSig(info.Types[n.Type].Type.(*types.Signature))
+			}
+			return true
+		})
+	}
+}
+
+//!-
+
+func main() {
+	flag.Parse()
+
+	// The loader loads a complete Go program from source code.
+	var conf loader.Config
+	_, err := conf.FromArgs(flag.Args(), false)
+	if err != nil {
+		log.Fatal(err) // command syntax error
+	}
+	lprog, err := conf.Load()
+	if err != nil {
+		log.Fatal(err) // load error
+	}
+
+	for _, info := range lprog.InitialPackages() {
+		PrintHugeParams(lprog.Fset, &info.Info, info.Files)
+	}
+}
+
+/*
+//!+output
+% ./hugeparam encoding/xml
+/go/src/encoding/xml/marshal.go:167:50: "start" parameter: encoding/xml.StartElement = 56 bytes
+/go/src/encoding/xml/marshal.go:734:97: "" result: encoding/xml.StartElement = 56 bytes
+/go/src/encoding/xml/marshal.go:761:51: "start" parameter: encoding/xml.StartElement = 56 bytes
+/go/src/encoding/xml/marshal.go:781:68: "start" parameter: encoding/xml.StartElement = 56 bytes
+/go/src/encoding/xml/xml.go:72:30: "" result: encoding/xml.StartElement = 56 bytes
+//!-output
+*/
@@ -0,0 +1,77 @@
+package main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/importer"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"log"
+)
+
+//!+input
+const input = `package main
+
+type A struct{}
+func (*A) f()
+
+type B int
+func (B) f()
+func (*B) g()
+
+type I interface { f() }
+type J interface { g() }
+`
+
+//!-input
+
+func main() {
+	// Parse one file.
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "input.go", input, 0)
+	if err != nil {
+		log.Fatal(err) // parse error
+	}
+	conf := types.Config{Importer: importer.Default()}
+	pkg, err := conf.Check("hello", fset, []*ast.File{f}, nil)
+	if err != nil {
+		log.Fatal(err) // type error
+	}
+
+	//!+implements
+	// Find all named types at package level.
+	var allNamed []*types.Named
+	for _, name := range pkg.Scope().Names() {
+		if obj, ok := pkg.Scope().Lookup(name).(*types.TypeName); ok {
+			allNamed = append(allNamed, obj.Type().(*types.Named))
+		}
+	}
+
+	// Test assignability of all distinct pairs of
+	// named types (T, U) where U is an interface.
+	for _, T := range allNamed {
+		for _, U := range allNamed {
+			if T == U || !types.IsInterface(U) {
+				continue
+			}
+			if types.AssignableTo(T, U) {
+				fmt.Printf("%s satisfies %s\n", T, U)
+			} else if !types.IsInterface(T) &&
+				types.AssignableTo(types.NewPointer(T), U) {
+				fmt.Printf("%s satisfies %s\n", types.NewPointer(T), U)
+			}
+		}
+	}
+	//!-implements
+}
+
+/*
+//!+output
+$ go build github.com/golang/example/gotypes/implements
+$ ./implements
+*hello.A satisfies hello.I
+hello.B satisfies hello.I
+*hello.B satisfies hello.J
+//!-output
+*/
@@ -0,0 +1,77 @@
+package main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/importer"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"log"
+	"strings"
+)
+
+//!+input
+const hello = `
+package main
+
+import "fmt"
+
+// append
+func main() {
+        // fmt
+        fmt.Println("Hello, world")
+        // main
+        main, x := 1, 2
+        // main
+        print(main, x)
+        // x
+}
+// x
+`
+
+//!-input
+
+//!+main
+func main() {
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "hello.go", hello, parser.ParseComments)
+	if err != nil {
+		log.Fatal(err) // parse error
+	}
+
+	conf := types.Config{Importer: importer.Default()}
+	pkg, err := conf.Check("cmd/hello", fset, []*ast.File{f}, nil)
+	if err != nil {
+		log.Fatal(err) // type error
+	}
+
+	// Each comment contains a name.
+	// Look up that name in the innermost scope enclosing the comment.
+	for _, comment := range f.Comments {
+		pos := comment.Pos()
+		name := strings.TrimSpace(comment.Text())
+		fmt.Printf("At %s,\t%q = ", fset.Position(pos), name)
+		inner := pkg.Scope().Innermost(pos)
+		if _, obj := inner.LookupParent(name, pos); obj != nil {
+			fmt.Println(obj)
+		} else {
+			fmt.Println("not found")
+		}
+	}
+}
+
+//!-main
+
+/*
+//!+output
+$ go build github.com/golang/example/gotypes/lookup
+$ ./lookup
+At hello.go:6:1,        "append" = builtin append
+At hello.go:8:9,        "fmt" = package fmt
+At hello.go:10:9,       "main" = func cmd/hello.main()
+At hello.go:12:9,       "main" = var main int
+At hello.go:14:9,       "x" = var x int
+At hello.go:16:1,       "x" = not found
+//!-output
+*/
@@ -0,0 +1,104 @@
+package main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/importer"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"log"
+)
+
+//!+input
+const input = `package main
+
+import "bytes"
+
+func main() {
+	var buf bytes.Buffer
+	if buf.Bytes == nil && bytes.Repeat != nil && main == nil {
+		// ...
+	}
+}
+`
+
+//!-input
+
+var fset = token.NewFileSet()
+
+func main() {
+	f, err := parser.ParseFile(fset, "input.go", input, 0)
+	if err != nil {
+		log.Fatal(err) // parse error
+	}
+	conf := types.Config{Importer: importer.Default()}
+	info := &types.Info{
+		Defs:  make(map[*ast.Ident]types.Object),
+		Uses:  make(map[*ast.Ident]types.Object),
+		Types: make(map[ast.Expr]types.TypeAndValue),
+	}
+	if _, err = conf.Check("cmd/hello", fset, []*ast.File{f}, info); err != nil {
+		log.Fatal(err) // type error
+	}
+
+	ast.Inspect(f, func(n ast.Node) bool {
+		if n != nil {
+			CheckNilFuncComparison(info, n)
+		}
+		return true
+	})
+}
+
+//!+
+// CheckNilFuncComparison reports unintended comparisons
+// of functions against nil, e.g., "if x.Method == nil {".
+func CheckNilFuncComparison(info *types.Info, n ast.Node) {
+	e, ok := n.(*ast.BinaryExpr)
+	if !ok {
+		return // not a binary operation
+	}
+	if e.Op != token.EQL && e.Op != token.NEQ {
+		return // not a comparison
+	}
+
+	// If this is a comparison against nil, find the other operand.
+	var other ast.Expr
+	if info.Types[e.X].IsNil() {
+		other = e.Y
+	} else if info.Types[e.Y].IsNil() {
+		other = e.X
+	} else {
+		return // not a comparison against nil
+	}
+
+	// Find the object.
+	var obj types.Object
+	switch v := other.(type) {
+	case *ast.Ident:
+		obj = info.Uses[v]
+	case *ast.SelectorExpr:
+		obj = info.Uses[v.Sel]
+	default:
+		return // not an identifier or selection
+	}
+
+	if _, ok := obj.(*types.Func); !ok {
+		return // not a function or method
+	}
+
+	fmt.Printf("%s: comparison of function %v %v nil is always %v\n",
+		fset.Position(e.Pos()), obj.Name(), e.Op, e.Op == token.NEQ)
+}
+
+//!-
+
+/*
+//!+output
+$ go build github.com/golang/example/gotypes/nilfunc
+$ ./nilfunc
+input.go:7:5: comparison of function Bytes == nil is always false
+input.go:7:25: comparison of function Repeat != nil is always true
+input.go:7:48: comparison of function main == nil is always false
+//!-output
+*/
@@ -0,0 +1,64 @@
+//!+
+package main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/importer"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"log"
+)
+
+const hello = `package main
+
+import "fmt"
+
+func main() {
+        fmt.Println("Hello, world")
+}`
+
+func main() {
+	fset := token.NewFileSet()
+
+	// Parse the input string, []byte, or io.Reader,
+	// recording position information in fset.
+	// ParseFile returns an *ast.File, a syntax tree.
+	f, err := parser.ParseFile(fset, "hello.go", hello, 0)
+	if err != nil {
+		log.Fatal(err) // parse error
+	}
+
+	// A Config controls various options of the type checker.
+	// The defaults work fine except for one setting:
+	// we must specify how to deal with imports.
+	conf := types.Config{Importer: importer.Default()}
+
+	// Type-check the package containing only file f.
+	// Check returns a *types.Package.
+	pkg, err := conf.Check("cmd/hello", fset, []*ast.File{f}, nil)
+	if err != nil {
+		log.Fatal(err) // type error
+	}
+
+	fmt.Printf("Package  %q\n", pkg.Path())
+	fmt.Printf("Name:    %s\n", pkg.Name())
+	fmt.Printf("Imports: %s\n", pkg.Imports())
+	fmt.Printf("Scope:   %s\n", pkg.Scope())
+}
+
+//!-
+
+/*
+//!+output
+$ go build github.com/golang/example/gotypes/pkginfo
+$ ./pkginfo
+Package  "cmd/hello"
+Name:    main
+Imports: [package fmt ("fmt")]
+Scope:   package "cmd/hello" scope 0x820533590 {
+.  func cmd/hello.main()
+}
+//!-output
+*/
@@ -0,0 +1,115 @@
+// The skeleton command prints the boilerplate for a concrete type
+// that implements the specified interface type.
+//
+// Example:
+//	$ ./skeleton io ReadWriteCloser buffer
+//	// *buffer implements io.ReadWriteCloser.
+//	type buffer struct{ /* ... */ }
+//	func (b *buffer) Close() error { panic("unimplemented") }
+//	func (b *buffer) Read(p []byte) (n int, err error) { panic("unimplemented") }
+//	func (b *buffer) Write(p []byte) (n int, err error) { panic("unimplemented") }
+package main
+
+import (
+	"fmt"
+	"go/types"
+	"log"
+	"os"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"golang.org/x/tools/go/loader"
+)
+
+const usage = "Usage: skeleton <package> <interface> <concrete>"
+
+//!+
+func PrintSkeleton(pkg *types.Package, ifacename, concname string) error {
+	obj := pkg.Scope().Lookup(ifacename)
+	if obj == nil {
+		return fmt.Errorf("%s.%s not found", pkg.Path(), ifacename)
+	}
+	if _, ok := obj.(*types.TypeName); !ok {
+		return fmt.Errorf("%v is not a named type", obj)
+	}
+	iface, ok := obj.Type().Underlying().(*types.Interface)
+	if !ok {
+		return fmt.Errorf("type %v is a %T, not an interface",
+			obj, obj.Type().Underlying())
+	}
+	// Use first letter of type name as receiver parameter.
+	if !isValidIdentifier(concname) {
+		return fmt.Errorf("invalid concrete type name: %q", concname)
+	}
+	r, _ := utf8.DecodeRuneInString(concname)
+
+	fmt.Printf("// *%s implements %s.%s.\n", concname, pkg.Path(), ifacename)
+	fmt.Printf("type %s struct{}\n", concname)
+	mset := types.NewMethodSet(iface)
+	for i := 0; i < mset.Len(); i++ {
+		meth := mset.At(i).Obj()
+		sig := types.TypeString(meth.Type(), (*types.Package).Name)
+		fmt.Printf("func (%c *%s) %s%s {\n\tpanic(\"unimplemented\")\n}\n",
+			r, concname, meth.Name(),
+			strings.TrimPrefix(sig, "func"))
+	}
+	return nil
+}
+
+//!-
+
+func isValidIdentifier(id string) bool {
+	for i, r := range id {
+		if !unicode.IsLetter(r) &&
+			!(i > 0 && unicode.IsDigit(r)) {
+			return false
+		}
+	}
+	return id != ""
+}
+
+func main() {
+	if len(os.Args) != 4 {
+		log.Fatal(usage)
+	}
+	pkgpath, ifacename, concname := os.Args[1], os.Args[2], os.Args[3]
+
+	// The loader loads a complete Go program from source code.
+	var conf loader.Config
+	conf.Import(pkgpath)
+	lprog, err := conf.Load()
+	if err != nil {
+		log.Fatal(err) // load error
+	}
+	pkg := lprog.Package(pkgpath).Pkg
+	if err := PrintSkeleton(pkg, ifacename, concname); err != nil {
+		log.Fatal(err)
+	}
+}
+
+/*
+//!+output1
+$ ./skeleton io ReadWriteCloser buffer
+// *buffer implements io.ReadWriteCloser.
+type buffer struct{}
+func (b *buffer) Close() error {
+	panic("unimplemented")
+}
+func (b *buffer) Read(p []byte) (n int, err error) {
+	panic("unimplemented")
+}
+func (b *buffer) Write(p []byte) (n int, err error) {
+	panic("unimplemented")
+}
+//!-output1
+
+//!+output2
+$ ./skeleton net/http Handler myHandler
+// *myHandler implements net/http.Handler.
+type myHandler struct{}
+func (m *myHandler) ServeHTTP(http.ResponseWriter, *http.Request) {
+	panic("unimplemented")
+}
+//!-output2
+*/
@@ -0,0 +1,134 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/format"
+	"go/importer"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"log"
+)
+
+//!+input
+const input = `
+package main
+
+var m = make(map[string]int)
+
+func main() {
+	v, ok := m["hello, " + "world"]
+	print(rune(v), ok)
+}
+`
+
+//!-input
+
+var fset = token.NewFileSet()
+
+func main() {
+	f, err := parser.ParseFile(fset, "hello.go", input, 0)
+	if err != nil {
+		log.Fatal(err) // parse error
+	}
+
+	conf := types.Config{Importer: importer.Default()}
+	info := &types.Info{Types: make(map[ast.Expr]types.TypeAndValue)}
+	if _, err := conf.Check("cmd/hello", fset, []*ast.File{f}, info); err != nil {
+		log.Fatal(err) // type error
+	}
+
+	//!+inspect
+	// f is a parsed, type-checked *ast.File.
+	ast.Inspect(f, func(n ast.Node) bool {
+		if expr, ok := n.(ast.Expr); ok {
+			if tv, ok := info.Types[expr]; ok {
+				fmt.Printf("%-24s\tmode:  %s\n", nodeString(expr), mode(tv))
+				fmt.Printf("\t\t\t\ttype:  %v\n", tv.Type)
+				if tv.Value != nil {
+					fmt.Printf("\t\t\t\tvalue: %v\n", tv.Value)
+				}
+			}
+		}
+		return true
+	})
+	//!-inspect
+}
+
+// nodeString formats a syntax tree in the style of gofmt.
+func nodeString(n ast.Node) string {
+	var buf bytes.Buffer
+	format.Node(&buf, fset, n)
+	return buf.String()
+}
+
+// mode returns a string describing the mode of an expression.
+func mode(tv types.TypeAndValue) string {
+	s := ""
+	if tv.IsVoid() {
+		s += ",void"
+	}
+	if tv.IsType() {
+		s += ",type"
+	}
+	if tv.IsBuiltin() {
+		s += ",builtin"
+	}
+	if tv.IsValue() {
+		s += ",value"
+	}
+	if tv.IsNil() {
+		s += ",nil"
+	}
+	if tv.Addressable() {
+		s += ",addressable"
+	}
+	if tv.Assignable() {
+		s += ",assignable"
+	}
+	if tv.HasOk() {
+		s += ",ok"
+	}
+	return s[1:]
+}
+
+/*
+//!+output
+$ go build github.com/golang/example/gotypes/typeandvalue
+$ ./typeandvalue
+make(map[string]int)            mode:  value
+                                type:  map[string]int
+make                            mode:  builtin
+                                type:  func(map[string]int) map[string]int
+map[string]int                  mode:  type
+                                type:  map[string]int
+string                          mode:  type
+                                type:  string
+int                             mode:  type
+                                type:  int
+m["hello, "+"world"]            mode:  value,assignable,ok
+                                type:  (int, bool)
+m                               mode:  value,addressable,assignable
+                                type:  map[string]int
+"hello, " + "world"             mode:  value
+                                type:  string
+                                value: "hello, world"
+"hello, "                       mode:  value
+                                type:  untyped string
+                                value: "hello, "
+"world"                         mode:  value
+                                type:  untyped string
+                                value: "world"
+print(rune(v), ok)              mode:  void
+                                type:  ()
+print                           mode:  builtin
+                                type:  func(rune, bool)
+rune(v)                         mode:  value
+                                type:  rune
+rune                            mode:  type
+                                type:  rune
+...more not shown...
+//!-output
+*/
@@ -0,0 +1,191 @@
+// The weave command is a simple preprocessor for markdown files.
+// It builds a table of contents and processes %include directives.
+//
+// Example usage:
+// 	$ go run weave.go go-types.md > README.md
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+func main() {
+	log.SetFlags(0)
+	log.SetPrefix("weave: ")
+	if len(os.Args) != 2 {
+		log.Fatal("usage: weave input.md\n")
+	}
+
+	f, err := os.Open(os.Args[1])
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer f.Close()
+
+	fmt.Println("<!-- Autogenerated by weave; DO NOT EDIT -->")
+
+	// Pass 1.
+	var toc []string
+	in := bufio.NewScanner(f)
+	for in.Scan() {
+		line := in.Text()
+		if line == "" || (line[0] != '#' && line[0] != '%') {
+			continue
+		}
+		line = strings.TrimSpace(line)
+		if line == "%toc" {
+			toc = nil
+		} else if strings.HasPrefix(line, "# ") || strings.HasPrefix(line, "## ") {
+			words := strings.Fields(line)
+			depth := len(words[0])
+			words = words[1:]
+			text := strings.Join(words, " ")
+			for i := range words {
+				words[i] = strings.ToLower(words[i])
+			}
+			line = fmt.Sprintf("%s1. [%s](#%s)",
+				strings.Repeat("\t", depth-1), text, strings.Join(words, "-"))
+			toc = append(toc, line)
+		}
+	}
+
+	// Pass 2.
+	if _, err := f.Seek(0, os.SEEK_SET); err != nil {
+		log.Fatalf("can't rewind input: %v", err)
+	}
+	in = bufio.NewScanner(f)
+	for in.Scan() {
+		line := in.Text()
+		switch {
+		case strings.HasPrefix(line, "%toc"): // ToC
+			for _, h := range toc {
+				fmt.Println(h)
+			}
+		case strings.HasPrefix(line, "%include"):
+			words := strings.Fields(line)
+			if len(words) < 2 {
+				log.Fatal(line)
+			}
+			filename := words[1]
+
+			// Show caption unless '-' follows.
+			if len(words) < 4 || words[3] != "-" {
+				fmt.Printf("	// go get github.com/golang/example/gotypes/%s\n\n",
+					filepath.Dir(filename))
+			}
+
+			section := ""
+			if len(words) > 2 {
+				section = words[2]
+			}
+			s, err := include(filename, section)
+			if err != nil {
+				log.Fatal(err)
+			}
+			fmt.Println("```")
+			fmt.Println(cleanListing(s)) // TODO(adonovan): escape /^```/ in s
+			fmt.Println("```")
+		default:
+			fmt.Println(line)
+		}
+
+	}
+}
+
+// include processes an included file, and returns the included text.
+// Only lines between those matching !+tag and !-tag will be returned.
+// This is true even if tag=="".
+func include(file, tag string) (string, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	startre, err := regexp.Compile("!\\+" + tag + "$")
+	if err != nil {
+		return "", err
+	}
+	endre, err := regexp.Compile("!\\-" + tag + "$")
+	if err != nil {
+		return "", err
+	}
+
+	var text bytes.Buffer
+	in := bufio.NewScanner(f)
+	var on bool
+	for in.Scan() {
+		line := in.Text()
+		switch {
+		case startre.MatchString(line):
+			on = true
+		case endre.MatchString(line):
+			on = false
+		case on:
+			text.WriteByte('\t')
+			text.WriteString(line)
+			text.WriteByte('\n')
+		}
+	}
+	if text.Len() == 0 {
+		return "", fmt.Errorf("no lines of %s matched tag %q", file, tag)
+	}
+	return text.String(), nil
+}
+
+func isBlank(line string) bool { return strings.TrimSpace(line) == "" }
+
+func indented(line string) bool {
+	return strings.HasPrefix(line, "    ") || strings.HasPrefix(line, "\t")
+}
+
+// cleanListing removes entirely blank leading and trailing lines from
+// text, and removes n leading tabs.
+func cleanListing(text string) string {
+	lines := strings.Split(text, "\n")
+
+	// remove minimum number of leading tabs from all non-blank lines
+	tabs := 999
+	for i, line := range lines {
+		if strings.TrimSpace(line) == "" {
+			lines[i] = ""
+		} else {
+			if n := leadingTabs(line); n < tabs {
+				tabs = n
+			}
+		}
+	}
+	for i, line := range lines {
+		if line != "" {
+			line := line[tabs:]
+			lines[i] = line // remove leading tabs
+		}
+	}
+
+	// remove leading blank lines
+	for len(lines) > 0 && lines[0] == "" {
+		lines = lines[1:]
+	}
+	// remove trailing blank lines
+	for len(lines) > 0 && lines[len(lines)-1] == "" {
+		lines = lines[:len(lines)-1]
+	}
+	return strings.Join(lines, "\n")
+}
+
+func leadingTabs(s string) int {
+	var i int
+	for i = 0; i < len(s); i++ {
+		if s[i] != '\t' {
+			break
+		}
+	}
+	return i
+}
@@ -0,0 +1,27 @@
+/*
+Copyright 2014 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"fmt"
+
+	"github.com/golang/example/stringutil"
+)
+
+func main() {
+	fmt.Println(stringutil.Reverse("!selpmaxe oG ,olleH"))
+}
@@ -0,0 +1,2 @@
+FROM golang:onbuild
+EXPOSE 8080
@@ -0,0 +1,8 @@
+version: v1beta2
+containers:
+- name: outyet
+  image: adg1/outyet
+  ports:
+  - name: http
+    hostPort: 80
+    containerPort: 8080
@@ -0,0 +1,140 @@
+/*
+Copyright 2014 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// outyet is a web server that announces whether or not a particular Go version
+// has been tagged.
+package main
+
+import (
+	"expvar"
+	"flag"
+	"fmt"
+	"html/template"
+	"log"
+	"net/http"
+	"sync"
+	"time"
+)
+
+// Command-line flags.
+var (
+	httpAddr   = flag.String("http", ":8080", "Listen address")
+	pollPeriod = flag.Duration("poll", 5*time.Second, "Poll period")
+	version    = flag.String("version", "1.4", "Go version")
+)
+
+const baseChangeURL = "https://go.googlesource.com/go/+/"
+
+func main() {
+	flag.Parse()
+	changeURL := fmt.Sprintf("%sgo%s", baseChangeURL, *version)
+	http.Handle("/", NewServer(*version, changeURL, *pollPeriod))
+	log.Fatal(http.ListenAndServe(*httpAddr, nil))
+}
+
+// Exported variables for monitoring the server.
+// These are exported via HTTP as a JSON object at /debug/vars.
+var (
+	hitCount       = expvar.NewInt("hitCount")
+	pollCount      = expvar.NewInt("pollCount")
+	pollError      = expvar.NewString("pollError")
+	pollErrorCount = expvar.NewInt("pollErrorCount")
+)
+
+// Server implements the outyet server.
+// It serves the user interface (it's an http.Handler)
+// and polls the remote repository for changes.
+type Server struct {
+	version string
+	url     string
+	period  time.Duration
+
+	mu  sync.RWMutex // protects the yes variable
+	yes bool
+}
+
+// NewServer returns an initialized outyet server.
+func NewServer(version, url string, period time.Duration) *Server {
+	s := &Server{version: version, url: url, period: period}
+	go s.poll()
+	return s
+}
+
+// poll polls the change URL for the specified period until the tag exists.
+// Then it sets the Server's yes field true and exits.
+func (s *Server) poll() {
+	for !isTagged(s.url) {
+		pollSleep(s.period)
+	}
+	s.mu.Lock()
+	s.yes = true
+	s.mu.Unlock()
+	pollDone()
+}
+
+// Hooks that may be overridden for integration tests.
+var (
+	pollSleep = time.Sleep
+	pollDone  = func() {}
+)
+
+// isTagged makes an HTTP HEAD request to the given URL and reports whether it
+// returned a 200 OK response.
+func isTagged(url string) bool {
+	pollCount.Add(1)
+	r, err := http.Head(url)
+	if err != nil {
+		log.Print(err)
+		pollError.Set(err.Error())
+		pollErrorCount.Add(1)
+		return false
+	}
+	return r.StatusCode == http.StatusOK
+}
+
+// ServeHTTP implements the HTTP user interface.
+func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	hitCount.Add(1)
+	s.mu.RLock()
+	data := struct {
+		URL     string
+		Version string
+		Yes     bool
+	}{
+		s.url,
+		s.version,
+		s.yes,
+	}
+	s.mu.RUnlock()
+	err := tmpl.Execute(w, data)
+	if err != nil {
+		log.Print(err)
+	}
+}
+
+// tmpl is the HTML template that drives the user interface.
+var tmpl = template.Must(template.New("tmpl").Parse(`
+<!DOCTYPE html><html><body><center>
+	<h2>Is Go {{.Version}} out yet?</h2>
+	<h1>
+	{{if .Yes}}
+		<a href="{{.URL}}">YES!</a>
+	{{else}}
+		No. :-(
+	{{end}}
+	</h1>
+</center></body></html>
+`))
@@ -0,0 +1,99 @@
+/*
+Copyright 2014 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+)
+
+// statusHandler is an http.Handler that writes an empty response using itself
+// as the response status code.
+type statusHandler int
+
+func (h *statusHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	w.WriteHeader(int(*h))
+}
+
+func TestIsTagged(t *testing.T) {
+	// Set up a fake "Google Code" web server reporting 404 not found.
+	status := statusHandler(http.StatusNotFound)
+	s := httptest.NewServer(&status)
+	defer s.Close()
+
+	if isTagged(s.URL) {
+		t.Fatal("isTagged == true, want false")
+	}
+
+	// Change fake server status to 200 OK and try again.
+	status = http.StatusOK
+
+	if !isTagged(s.URL) {
+		t.Fatal("isTagged == false, want true")
+	}
+}
+
+func TestIntegration(t *testing.T) {
+	status := statusHandler(http.StatusNotFound)
+	ts := httptest.NewServer(&status)
+	defer ts.Close()
+
+	// Replace the pollSleep with a closure that we can block and unblock.
+	sleep := make(chan bool)
+	pollSleep = func(time.Duration) {
+		sleep <- true
+		sleep <- true
+	}
+
+	// Replace pollDone with a closure that will tell us when the poller is
+	// exiting.
+	done := make(chan bool)
+	pollDone = func() { done <- true }
+
+	// Put things as they were when the test finishes.
+	defer func() {
+		pollSleep = time.Sleep
+		pollDone = func() {}
+	}()
+
+	s := NewServer("1.x", ts.URL, 1*time.Millisecond)
+
+	<-sleep // Wait for poll loop to start sleeping.
+
+	// Make first request to the server.
+	r, _ := http.NewRequest("GET", "/", nil)
+	w := httptest.NewRecorder()
+	s.ServeHTTP(w, r)
+	if b := w.Body.String(); !strings.Contains(b, "No.") {
+		t.Fatalf("body = %s, want no", b)
+	}
+
+	status = http.StatusOK
+
+	<-sleep // Permit poll loop to stop sleeping.
+	<-done  // Wait for poller to see the "OK" status and exit.
+
+	// Make second request to the server.
+	w = httptest.NewRecorder()
+	s.ServeHTTP(w, r)
+	if b := w.Body.String(); !strings.Contains(b, "YES!") {
+		t.Fatalf("body = %q, want yes", b)
+	}
+}
@@ -0,0 +1,27 @@
+/*
+Copyright 2014 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package stringutil contains utility functions for working with strings.
+package stringutil
+
+// Reverse returns its argument string reversed rune-wise left to right.
+func Reverse(s string) string {
+	r := []rune(s)
+	for i, j := 0, len(r)-1; i < len(r)/2; i, j = i+1, j-1 {
+		r[i], r[j] = r[j], r[i]
+	}
+	return string(r)
+}
@@ -0,0 +1,34 @@
+/*
+Copyright 2014 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package stringutil
+
+import "testing"
+
+func TestReverse(t *testing.T) {
+	for _, c := range []struct {
+		in, want string
+	}{
+		{"Hello, world", "dlrow ,olleH"},
+		{"Hello, 世界", "界世 ,olleH"},
+		{"", ""},
+	} {
+		got := Reverse(c.in)
+		if got != c.want {
+			t.Errorf("Reverse(%q) == %q, want %q", c.in, got, c.want)
+		}
+	}
+}
@@ -0,0 +1,9 @@
+{{define "content"}}
+<div id="image">
+	<img src="{{.URL}}" title="{{.Title}}" alt="{{.Title}}">
+</div>
+{{end}}
+
+{{define "sidebar"}}
+<a href="/">Back</a>
+{{end}}
@@ -0,0 +1,41 @@
+<!DOCTYPE html>
+<html>
+	<head>
+		<meta charset="utf-8">
+		<title>{{.Title}}</title>
+		<style>
+			body {
+				font-family: sans-serif;
+			}
+			h1 {
+				background: #ddd;
+			}
+			#sidebar {
+				float: right;
+			}
+		</style>
+	</head>
+	<body>
+		<h1>{{.Title}}</h1>
+
+		<div id="sidebar">
+			{{block "sidebar" .}}
+			<h2>Links</h2>
+			{{/* The dashes in the following template directives
+			     ensure the generated HTML of this list contains no
+			     extraneous spaces or line breaks. */}}
+			<ul>
+				{{- range .Links}}
+				<li><a href="{{.URL}}">{{.Title}}</a></li>
+				{{- end}}
+			</ul>
+			{{end}}
+		</div>
+
+		{{block "content" .}}
+		<div id="content">
+			{{.Body}}
+		</div>
+		{{end}}
+	</body>
+</html>
@@ -0,0 +1,97 @@
+/*
+Copyright 2016 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Command template is a trivial web server that uses the text/template (and
+// html/template) package's "block" feature to implement a kind of template
+// inheritance.
+//
+// It should be executed from the directory in which the source resides,
+// as it will look for its template files in the current directory.
+package main
+
+import (
+	"html/template"
+	"log"
+	"net/http"
+	"strings"
+)
+
+func main() {
+	http.HandleFunc("/", indexHandler)
+	http.HandleFunc("/image/", imageHandler)
+	log.Fatal(http.ListenAndServe("localhost:8080", nil))
+}
+
+// indexTemplate is the main site template.
+// The default template includes two template blocks ("sidebar" and "content")
+// that may be replaced in templates derived from this one.
+var indexTemplate = template.Must(template.ParseFiles("index.tmpl"))
+
+// Index is a data structure used to populate an indexTemplate.
+type Index struct {
+	Title string
+	Body  string
+	Links []Link
+}
+
+type Link struct {
+	URL, Title string
+}
+
+// indexHandler is an HTTP handler that serves the index page.
+func indexHandler(w http.ResponseWriter, r *http.Request) {
+	data := &Index{
+		Title: "Image gallery",
+		Body:  "Welcome to the image gallery.",
+	}
+	for name, img := range images {
+		data.Links = append(data.Links, Link{
+			URL:   "/image/" + name,
+			Title: img.Title,
+		})
+	}
+	if err := indexTemplate.Execute(w, data); err != nil {
+		log.Println(err)
+	}
+}
+
+// imageTemplate is a clone of indexTemplate that provides
+// alternate "sidebar" and "content" templates.
+var imageTemplate = template.Must(template.Must(indexTemplate.Clone()).ParseFiles("image.tmpl"))
+
+// Image is a data structure used to populate an imageTemplate.
+type Image struct {
+	Title string
+	URL   string
+}
+
+// imageHandler is an HTTP handler that serves the image pages.
+func imageHandler(w http.ResponseWriter, r *http.Request) {
+	data, ok := images[strings.TrimPrefix(r.URL.Path, "/image/")]
+	if !ok {
+		http.NotFound(w, r)
+		return
+	}
+	if err := imageTemplate.Execute(w, data); err != nil {
+		log.Println(err)
+	}
+}
+
+// images specifies the site content: a collection of images.
+var images = map[string]*Image{
+	"go":     {"The Go Gopher", "https://golang.org/doc/gopher/frontpage.png"},
+	"google": {"The Google Logo", "https://www.google.com/images/branding/googlelogo/1x/googlelogo_color_272x92dp.png"},
+}
@@ -1,5 +0,0 @@
-package test
-
-func Test() string {
-    return "vendor hello world"
-}
@@ -1,4 +1,8 @@
 package: github.com/fission/fission
+excludeDirs:
+- examples
+- hack
+- test
 import:
 - package: github.com/sirupsen/logrus
  version: 68cec9f21fbf3ea8d8f98c044bc6ce05f17b267a