fn: docker version check2 (#744)

1) now required docker version is 17.06
2) enable circle ci latest docker install
3) docker driver & agent check minimum version before start

.circleci/config.yml

@@ -22,11 +22,11 @@ jobs:
           sudo tar -C /usr/local -xzf go$GOVERSION.$OS-$ARCH.tar.gz
       - run: go version
       # install latest Docker
-      #- run: |
-          #sudo rm -rf /var/cache/apt/archives && sudo ln -s ~/.apt-cache /var/cache/apt/archives && mkdir -p ~/.apt-cache/partial
-          #sudo service docker stop
-          #curl -fsSL https://get.docker.com/ | sudo sh
-          #docker version
+      - run: |
+          sudo rm -rf /var/cache/apt/archives && sudo ln -s ~/.apt-cache /var/cache/apt/archives && mkdir -p ~/.apt-cache/partial
+          sudo service docker stop
+          curl -fsSL https://get.docker.com/ | sudo sh
+          docker version
       - run: docker version
       - run: nproc
       - run: make clear-images

Gopkg.lock

@@ -103,6 +103,15 @@
   packages = ["pathdriver"]
   revision = "b2b946a77f5973f420514090d6f6dd58b08303f0"
 
+[[projects]]
+  name = "github.com/coreos/go-semver"
+  packages = [
+    ".",
+    "semver"
+  ]
+  revision = "8ab6407b697782a06568d4b7f1db25550ec2e4c6"
+  version = "v0.2.0"
+
 [[projects]]
   name = "github.com/davecgh/go-spew"
   packages = ["spew"]
@@ -669,6 +678,6 @@
 [solve-meta]
   analyzer-name = "dep"
   analyzer-version = 1
-  inputs-digest = "556d3a6039ee958f59418b978bbb50d2733c1069bdcb67c931ffa0ab09195097"
+  inputs-digest = "f5c10f8c63262754a0ceb541105cfac5448693af7997269bb1edce828eb3a551"
   solver-name = "gps-cdcl"
   solver-version = 1

Gopkg.toml

@@ -76,3 +76,7 @@ ignored = ["github.com/fnproject/fn/cli"]
 [[constraint]]
   name = "github.com/fsouza/go-dockerclient"
   revision = "98edf3edfae6a6500fecc69d2bcccf1302544004"
+
+[[constraint]]
+  name = "github.com/coreos/go-semver"
+  version = "0.2.0"

README.md

@@ -26,7 +26,7 @@ The fastest way to experience Fn is to follow the quickstart below, or you can j
 
 ### Pre-requisites
 
-* Docker 17.05 or later installed and running
+* Docker 17.06 or later installed and running
 * A Docker Hub account ([Docker Hub](https://hub.docker.com/)) (or other Docker-compliant registry)
 * Log Docker into your Docker Hub account: `docker login`
 

api/agent/agent.go

@@ -123,7 +123,9 @@ type agent struct {
 
 func New(da DataAccess) Agent {
 	// TODO: Create drivers.New(runnerConfig)
-	driver := docker.NewDocker(drivers.Config{})
+	driver := docker.NewDocker(drivers.Config{
+		ServerVersion: "17.06.0",
+	})
 
 	a := &agent{
 		da:          da,

api/agent/drivers/docker/docker.go

@@ -12,6 +12,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/coreos/go-semver/semver"
 	"github.com/fnproject/fn/api/agent/drivers"
 	"github.com/fnproject/fn/api/common"
 	"github.com/fnproject/fn/api/models"
@@ -58,12 +59,45 @@ func NewDocker(conf drivers.Config) *DockerDriver {
 		logrus.WithError(err).Fatal("couldn't resolve hostname")
 	}
 
-	return &DockerDriver{
+	driver := &DockerDriver{
 		conf:     conf,
 		docker:   newClient(),
 		hostname: hostname,
 		auths:    registryFromEnv(),
 	}
+
+	if conf.ServerVersion != "" {
+		err = checkDockerVersion(driver, conf.ServerVersion)
+		if err != nil {
+			logrus.WithError(err).Fatal("docker version error")
+		}
+	}
+
+	return driver
+}
+
+func checkDockerVersion(driver *DockerDriver, expected string) error {
+
+	info, err := driver.docker.Info(context.Background())
+	if err != nil {
+		return err
+	}
+
+	actual, err := semver.NewVersion(info.ServerVersion)
+	if err != nil {
+		return err
+	}
+
+	wanted, err := semver.NewVersion(expected)
+	if err != nil {
+		return err
+	}
+
+	if actual.Compare(*wanted) < 0 {
+		return fmt.Errorf("docker version is too old. Required: %s Found: %s", expected, info.ServerVersion)
+	}
+
+	return nil
 }
 
 func registryFromEnv() map[string]docker.AuthConfiguration {

api/agent/drivers/docker/docker_client.go

@@ -38,6 +38,7 @@ type dockerClient interface {
 	InspectImage(ctx context.Context, name string) (*docker.Image, error)
 	InspectContainerWithContext(container string, ctx context.Context) (*docker.Container, error)
 	Stats(opts docker.StatsOptions) error
+	Info(ctx context.Context) (*docker.DockerInfo, error)
 }
 
 // TODO: switch to github.com/docker/engine-api
@@ -169,6 +170,19 @@ func filterNoSuchContainer(ctx context.Context, err error) error {
 	return err
 }
 
+func (d *dockerWrap) Info(ctx context.Context) (info *docker.DockerInfo, err error) {
+	span, ctx := opentracing.StartSpanFromContext(ctx, "docker_server_version")
+	defer span.Finish()
+
+	ctx, cancel := context.WithTimeout(ctx, retryTimeout)
+	defer cancel()
+	err = d.retry(ctx, func() error {
+		info, err = d.docker.Info()
+		return err
+	})
+	return info, err
+}
+
 func (d *dockerWrap) AttachToContainerNonBlocking(ctx context.Context, opts docker.AttachToContainerOptions) (w docker.CloseWaiter, err error) {
 	span, ctx := opentracing.StartSpanFromContext(ctx, "docker_attach_container")
 	defer span.Finish()

api/agent/drivers/docker/docker_test.go

@@ -63,6 +63,26 @@ func TestRunnerDocker(t *testing.T) {
 	}
 }
 
+func TestRunnerDockerVersion(t *testing.T) {
+
+	dkr := NewDocker(drivers.Config{
+		ServerVersion: "0.0.0",
+	})
+	if dkr == nil {
+		t.Fatal("should not be nil")
+	}
+
+	err := checkDockerVersion(dkr, "1.0.0")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = checkDockerVersion(dkr, "9999.0.0")
+	if err == nil {
+		t.Fatal("should have failed")
+	}
+}
+
 func TestRunnerDockerStdin(t *testing.T) {
 	dkr := NewDocker(drivers.Config{})
 	ctx := context.Background()

api/agent/drivers/driver.go

@@ -178,15 +178,8 @@ const (
 type Config struct {
 	Docker string `json:"docker"`
 	// TODO CPUShares should likely be on a per container basis
-	CPUShares int64 `json:"cpu_shares"`
-}
-
-// for tests
-func DefaultConfig() Config {
-	return Config{
-		Docker:    "unix:///var/run/docker.sock",
-		CPUShares: 0,
-	}
+	CPUShares     int64  `json:"cpu_shares"`
+	ServerVersion string `json:"server_version"`
 }
 
 func average(samples []Stat) (Stat, bool) {

vendor/github.com/coreos/go-semver/.travis.yml

@@ -0,0 +1,8 @@
+language: go
+sudo: false
+go:
+  - 1.4
+  - 1.5
+  - 1.6
+  - tip
+script: cd semver && go test

vendor/github.com/coreos/go-semver/LICENSE

@@ -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,
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+   3. Grant of Patent License. Subject to the terms and conditions of
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+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
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+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
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+   4. Redistribution. You may reproduce and distribute copies of the
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+      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
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+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
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+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
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+          of the following places: within a NOTICE text file distributed
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+          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
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+
+      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
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+      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.

vendor/github.com/coreos/go-semver/README.md

@@ -0,0 +1,28 @@
+# go-semver - Semantic Versioning Library
+
+[![Build Status](https://travis-ci.org/coreos/go-semver.svg?branch=master)](https://travis-ci.org/coreos/go-semver)
+[![GoDoc](https://godoc.org/github.com/coreos/go-semver/semver?status.svg)](https://godoc.org/github.com/coreos/go-semver/semver)
+
+go-semver is a [semantic versioning][semver] library for Go. It lets you parse
+and compare two semantic version strings.
+
+[semver]: http://semver.org/
+
+## Usage
+
+```go
+vA := semver.New("1.2.3")
+vB := semver.New("3.2.1")
+
+fmt.Printf("%s < %s == %t\n", vA, vB, vA.LessThan(*vB))
+```
+
+## Example Application
+
+```
+$ go run example.go 1.2.3 3.2.1
+1.2.3 < 3.2.1 == true
+
+$ go run example.go 5.2.3 3.2.1
+5.2.3 < 3.2.1 == false
+```

vendor/github.com/coreos/go-semver/example.go

@@ -0,0 +1,20 @@
+package main
+
+import (
+	"fmt"
+	"github.com/coreos/go-semver/semver"
+	"os"
+)
+
+func main() {
+	vA, err := semver.NewVersion(os.Args[1])
+	if err != nil {
+		fmt.Println(err.Error())
+	}
+	vB, err := semver.NewVersion(os.Args[2])
+	if err != nil {
+		fmt.Println(err.Error())
+	}
+
+	fmt.Printf("%s < %s == %t\n", vA, vB, vA.LessThan(*vB))
+}

vendor/github.com/coreos/go-semver/semver/semver.go

@@ -0,0 +1,268 @@
+// Copyright 2013-2015 CoreOS, 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.
+
+// Semantic Versions http://semver.org
+package semver
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+type Version struct {
+	Major      int64
+	Minor      int64
+	Patch      int64
+	PreRelease PreRelease
+	Metadata   string
+}
+
+type PreRelease string
+
+func splitOff(input *string, delim string) (val string) {
+	parts := strings.SplitN(*input, delim, 2)
+
+	if len(parts) == 2 {
+		*input = parts[0]
+		val = parts[1]
+	}
+
+	return val
+}
+
+func New(version string) *Version {
+	return Must(NewVersion(version))
+}
+
+func NewVersion(version string) (*Version, error) {
+	v := Version{}
+
+	if err := v.Set(version); err != nil {
+		return nil, err
+	}
+
+	return &v, nil
+}
+
+// Must is a helper for wrapping NewVersion and will panic if err is not nil.
+func Must(v *Version, err error) *Version {
+	if err != nil {
+		panic(err)
+	}
+	return v
+}
+
+// Set parses and updates v from the given version string. Implements flag.Value
+func (v *Version) Set(version string) error {
+	metadata := splitOff(&version, "+")
+	preRelease := PreRelease(splitOff(&version, "-"))
+	dotParts := strings.SplitN(version, ".", 3)
+
+	if len(dotParts) != 3 {
+		return fmt.Errorf("%s is not in dotted-tri format", version)
+	}
+
+	parsed := make([]int64, 3, 3)
+
+	for i, v := range dotParts[:3] {
+		val, err := strconv.ParseInt(v, 10, 64)
+		parsed[i] = val
+		if err != nil {
+			return err
+		}
+	}
+
+	v.Metadata = metadata
+	v.PreRelease = preRelease
+	v.Major = parsed[0]
+	v.Minor = parsed[1]
+	v.Patch = parsed[2]
+	return nil
+}
+
+func (v Version) String() string {
+	var buffer bytes.Buffer
+
+	fmt.Fprintf(&buffer, "%d.%d.%d", v.Major, v.Minor, v.Patch)
+
+	if v.PreRelease != "" {
+		fmt.Fprintf(&buffer, "-%s", v.PreRelease)
+	}
+
+	if v.Metadata != "" {
+		fmt.Fprintf(&buffer, "+%s", v.Metadata)
+	}
+
+	return buffer.String()
+}
+
+func (v *Version) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var data string
+	if err := unmarshal(&data); err != nil {
+		return err
+	}
+	return v.Set(data)
+}
+
+func (v Version) MarshalJSON() ([]byte, error) {
+	return []byte(`"` + v.String() + `"`), nil
+}
+
+func (v *Version) UnmarshalJSON(data []byte) error {
+	l := len(data)
+	if l == 0 || string(data) == `""` {
+		return nil
+	}
+	if l < 2 || data[0] != '"' || data[l-1] != '"' {
+		return errors.New("invalid semver string")
+	}
+	return v.Set(string(data[1 : l-1]))
+}
+
+// Compare tests if v is less than, equal to, or greater than versionB,
+// returning -1, 0, or +1 respectively.
+func (v Version) Compare(versionB Version) int {
+	if cmp := recursiveCompare(v.Slice(), versionB.Slice()); cmp != 0 {
+		return cmp
+	}
+	return preReleaseCompare(v, versionB)
+}
+
+// Equal tests if v is equal to versionB.
+func (v Version) Equal(versionB Version) bool {
+	return v.Compare(versionB) == 0
+}
+
+// LessThan tests if v is less than versionB.
+func (v Version) LessThan(versionB Version) bool {
+	return v.Compare(versionB) < 0
+}
+
+// Slice converts the comparable parts of the semver into a slice of integers.
+func (v Version) Slice() []int64 {
+	return []int64{v.Major, v.Minor, v.Patch}
+}
+
+func (p PreRelease) Slice() []string {
+	preRelease := string(p)
+	return strings.Split(preRelease, ".")
+}
+
+func preReleaseCompare(versionA Version, versionB Version) int {
+	a := versionA.PreRelease
+	b := versionB.PreRelease
+
+	/* Handle the case where if two versions are otherwise equal it is the
+	 * one without a PreRelease that is greater */
+	if len(a) == 0 && (len(b) > 0) {
+		return 1
+	} else if len(b) == 0 && (len(a) > 0) {
+		return -1
+	}
+
+	// If there is a prerelease, check and compare each part.
+	return recursivePreReleaseCompare(a.Slice(), b.Slice())
+}
+
+func recursiveCompare(versionA []int64, versionB []int64) int {
+	if len(versionA) == 0 {
+		return 0
+	}
+
+	a := versionA[0]
+	b := versionB[0]
+
+	if a > b {
+		return 1
+	} else if a < b {
+		return -1
+	}
+
+	return recursiveCompare(versionA[1:], versionB[1:])
+}
+
+func recursivePreReleaseCompare(versionA []string, versionB []string) int {
+	// A larger set of pre-release fields has a higher precedence than a smaller set,
+	// if all of the preceding identifiers are equal.
+	if len(versionA) == 0 {
+		if len(versionB) > 0 {
+			return -1
+		}
+		return 0
+	} else if len(versionB) == 0 {
+		// We're longer than versionB so return 1.
+		return 1
+	}
+
+	a := versionA[0]
+	b := versionB[0]
+
+	aInt := false
+	bInt := false
+
+	aI, err := strconv.Atoi(versionA[0])
+	if err == nil {
+		aInt = true
+	}
+
+	bI, err := strconv.Atoi(versionB[0])
+	if err == nil {
+		bInt = true
+	}
+
+	// Handle Integer Comparison
+	if aInt && bInt {
+		if aI > bI {
+			return 1
+		} else if aI < bI {
+			return -1
+		}
+	}
+
+	// Handle String Comparison
+	if a > b {
+		return 1
+	} else if a < b {
+		return -1
+	}
+
+	return recursivePreReleaseCompare(versionA[1:], versionB[1:])
+}
+
+// BumpMajor increments the Major field by 1 and resets all other fields to their default values
+func (v *Version) BumpMajor() {
+	v.Major += 1
+	v.Minor = 0
+	v.Patch = 0
+	v.PreRelease = PreRelease("")
+	v.Metadata = ""
+}
+
+// BumpMinor increments the Minor field by 1 and resets all other fields to their default values
+func (v *Version) BumpMinor() {
+	v.Minor += 1
+	v.Patch = 0
+	v.PreRelease = PreRelease("")
+	v.Metadata = ""
+}
+
+// BumpPatch increments the Patch field by 1 and resets all other fields to their default values
+func (v *Version) BumpPatch() {
+	v.Patch += 1
+	v.PreRelease = PreRelease("")
+	v.Metadata = ""
+}

vendor/github.com/coreos/go-semver/semver/semver_test.go

@@ -0,0 +1,370 @@
+// Copyright 2013-2015 CoreOS, 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 semver
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"flag"
+	"fmt"
+	"math/rand"
+	"reflect"
+	"testing"
+	"time"
+
+	"gopkg.in/yaml.v2"
+)
+
+type fixture struct {
+	GreaterVersion string
+	LesserVersion  string
+}
+
+var fixtures = []fixture{
+	fixture{"0.0.0", "0.0.0-foo"},
+	fixture{"0.0.1", "0.0.0"},
+	fixture{"1.0.0", "0.9.9"},
+	fixture{"0.10.0", "0.9.0"},
+	fixture{"0.99.0", "0.10.0"},
+	fixture{"2.0.0", "1.2.3"},
+	fixture{"0.0.0", "0.0.0-foo"},
+	fixture{"0.0.1", "0.0.0"},
+	fixture{"1.0.0", "0.9.9"},
+	fixture{"0.10.0", "0.9.0"},
+	fixture{"0.99.0", "0.10.0"},
+	fixture{"2.0.0", "1.2.3"},
+	fixture{"0.0.0", "0.0.0-foo"},
+	fixture{"0.0.1", "0.0.0"},
+	fixture{"1.0.0", "0.9.9"},
+	fixture{"0.10.0", "0.9.0"},
+	fixture{"0.99.0", "0.10.0"},
+	fixture{"2.0.0", "1.2.3"},
+	fixture{"1.2.3", "1.2.3-asdf"},
+	fixture{"1.2.3", "1.2.3-4"},
+	fixture{"1.2.3", "1.2.3-4-foo"},
+	fixture{"1.2.3-5-foo", "1.2.3-5"},
+	fixture{"1.2.3-5", "1.2.3-4"},
+	fixture{"1.2.3-5-foo", "1.2.3-5-Foo"},
+	fixture{"3.0.0", "2.7.2+asdf"},
+	fixture{"3.0.0+foobar", "2.7.2"},
+	fixture{"1.2.3-a.10", "1.2.3-a.5"},
+	fixture{"1.2.3-a.b", "1.2.3-a.5"},
+	fixture{"1.2.3-a.b", "1.2.3-a"},
+	fixture{"1.2.3-a.b.c.10.d.5", "1.2.3-a.b.c.5.d.100"},
+	fixture{"1.0.0", "1.0.0-rc.1"},
+	fixture{"1.0.0-rc.2", "1.0.0-rc.1"},
+	fixture{"1.0.0-rc.1", "1.0.0-beta.11"},
+	fixture{"1.0.0-beta.11", "1.0.0-beta.2"},
+	fixture{"1.0.0-beta.2", "1.0.0-beta"},
+	fixture{"1.0.0-beta", "1.0.0-alpha.beta"},
+	fixture{"1.0.0-alpha.beta", "1.0.0-alpha.1"},
+	fixture{"1.0.0-alpha.1", "1.0.0-alpha"},
+}
+
+func TestCompare(t *testing.T) {
+	for _, v := range fixtures {
+		gt, err := NewVersion(v.GreaterVersion)
+		if err != nil {
+			t.Error(err)
+		}
+
+		lt, err := NewVersion(v.LesserVersion)
+		if err != nil {
+			t.Error(err)
+		}
+
+		if gt.LessThan(*lt) {
+			t.Errorf("%s should not be less than %s", gt, lt)
+		}
+		if gt.Equal(*lt) {
+			t.Errorf("%s should not be equal to %s", gt, lt)
+		}
+		if gt.Compare(*lt) <= 0 {
+			t.Errorf("%s should be greater than %s", gt, lt)
+		}
+		if !lt.LessThan(*gt) {
+			t.Errorf("%s should be less than %s", lt, gt)
+		}
+		if !lt.Equal(*lt) {
+			t.Errorf("%s should be equal to %s", lt, lt)
+		}
+		if lt.Compare(*gt) > 0 {
+			t.Errorf("%s should not be greater than %s", lt, gt)
+		}
+	}
+}
+
+func testString(t *testing.T, orig string, version *Version) {
+	if orig != version.String() {
+		t.Errorf("%s != %s", orig, version)
+	}
+}
+
+func TestString(t *testing.T) {
+	for _, v := range fixtures {
+		gt, err := NewVersion(v.GreaterVersion)
+		if err != nil {
+			t.Error(err)
+		}
+		testString(t, v.GreaterVersion, gt)
+
+		lt, err := NewVersion(v.LesserVersion)
+		if err != nil {
+			t.Error(err)
+		}
+		testString(t, v.LesserVersion, lt)
+	}
+}
+
+func shuffleStringSlice(src []string) []string {
+	dest := make([]string, len(src))
+	rand.Seed(time.Now().Unix())
+	perm := rand.Perm(len(src))
+	for i, v := range perm {
+		dest[v] = src[i]
+	}
+	return dest
+}
+
+func TestSort(t *testing.T) {
+	sortedVersions := []string{"1.0.0", "1.0.2", "1.2.0", "3.1.1"}
+	unsortedVersions := shuffleStringSlice(sortedVersions)
+
+	semvers := []*Version{}
+	for _, v := range unsortedVersions {
+		sv, err := NewVersion(v)
+		if err != nil {
+			t.Fatal(err)
+		}
+		semvers = append(semvers, sv)
+	}
+
+	Sort(semvers)
+
+	for idx, sv := range semvers {
+		if sv.String() != sortedVersions[idx] {
+			t.Fatalf("incorrect sort at index %v", idx)
+		}
+	}
+}
+
+func TestBumpMajor(t *testing.T) {
+	version, _ := NewVersion("1.0.0")
+	version.BumpMajor()
+	if version.Major != 2 {
+		t.Fatalf("bumping major on 1.0.0 resulted in %v", version)
+	}
+
+	version, _ = NewVersion("1.5.2")
+	version.BumpMajor()
+	if version.Minor != 0 && version.Patch != 0 {
+		t.Fatalf("bumping major on 1.5.2 resulted in %v", version)
+	}
+
+	version, _ = NewVersion("1.0.0+build.1-alpha.1")
+	version.BumpMajor()
+	if version.PreRelease != "" && version.PreRelease != "" {
+		t.Fatalf("bumping major on 1.0.0+build.1-alpha.1 resulted in %v", version)
+	}
+}
+
+func TestBumpMinor(t *testing.T) {
+	version, _ := NewVersion("1.0.0")
+	version.BumpMinor()
+
+	if version.Major != 1 {
+		t.Fatalf("bumping minor on 1.0.0 resulted in %v", version)
+	}
+
+	if version.Minor != 1 {
+		t.Fatalf("bumping major on 1.0.0 resulted in %v", version)
+	}
+
+	version, _ = NewVersion("1.0.0+build.1-alpha.1")
+	version.BumpMinor()
+	if version.PreRelease != "" && version.PreRelease != "" {
+		t.Fatalf("bumping major on 1.0.0+build.1-alpha.1 resulted in %v", version)
+	}
+}
+
+func TestBumpPatch(t *testing.T) {
+	version, _ := NewVersion("1.0.0")
+	version.BumpPatch()
+
+	if version.Major != 1 {
+		t.Fatalf("bumping minor on 1.0.0 resulted in %v", version)
+	}
+
+	if version.Minor != 0 {
+		t.Fatalf("bumping major on 1.0.0 resulted in %v", version)
+	}
+
+	if version.Patch != 1 {
+		t.Fatalf("bumping major on 1.0.0 resulted in %v", version)
+	}
+
+	version, _ = NewVersion("1.0.0+build.1-alpha.1")
+	version.BumpPatch()
+	if version.PreRelease != "" && version.PreRelease != "" {
+		t.Fatalf("bumping major on 1.0.0+build.1-alpha.1 resulted in %v", version)
+	}
+}
+
+func TestMust(t *testing.T) {
+	tests := []struct {
+		versionStr string
+
+		version *Version
+		recov   interface{}
+	}{
+		{
+			versionStr: "1.0.0",
+			version:    &Version{Major: 1},
+		},
+		{
+			versionStr: "version number",
+			recov:      errors.New("version number is not in dotted-tri format"),
+		},
+	}
+
+	for _, tt := range tests {
+		func() {
+			defer func() {
+				recov := recover()
+				if !reflect.DeepEqual(tt.recov, recov) {
+					t.Fatalf("incorrect panic for %q: want %v, got %v", tt.versionStr, tt.recov, recov)
+				}
+			}()
+
+			version := Must(NewVersion(tt.versionStr))
+			if !reflect.DeepEqual(tt.version, version) {
+				t.Fatalf("incorrect version for %q: want %+v, got %+v", tt.versionStr, tt.version, version)
+			}
+		}()
+	}
+}
+
+type fixtureJSON struct {
+	GreaterVersion *Version
+	LesserVersion  *Version
+}
+
+func TestJSON(t *testing.T) {
+	fj := make([]fixtureJSON, len(fixtures))
+	for i, v := range fixtures {
+		var err error
+		fj[i].GreaterVersion, err = NewVersion(v.GreaterVersion)
+		if err != nil {
+			t.Fatal(err)
+		}
+		fj[i].LesserVersion, err = NewVersion(v.LesserVersion)
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	fromStrings, err := json.Marshal(fixtures)
+	if err != nil {
+		t.Fatal(err)
+	}
+	fromVersions, err := json.Marshal(fj)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(fromStrings, fromVersions) {
+		t.Errorf("Expected:   %s", fromStrings)
+		t.Errorf("Unexpected: %s", fromVersions)
+	}
+
+	fromJson := make([]fixtureJSON, 0, len(fj))
+	err = json.Unmarshal(fromStrings, &fromJson)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(fromJson, fj) {
+		t.Error("Expected:   ", fj)
+		t.Error("Unexpected: ", fromJson)
+	}
+}
+
+func TestYAML(t *testing.T) {
+	document, err := yaml.Marshal(fixtures)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	expected := make([]fixtureJSON, len(fixtures))
+	for i, v := range fixtures {
+		var err error
+		expected[i].GreaterVersion, err = NewVersion(v.GreaterVersion)
+		if err != nil {
+			t.Fatal(err)
+		}
+		expected[i].LesserVersion, err = NewVersion(v.LesserVersion)
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	fromYAML := make([]fixtureJSON, 0, len(fixtures))
+	err = yaml.Unmarshal(document, &fromYAML)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !reflect.DeepEqual(fromYAML, expected) {
+		t.Error("Expected:   ", expected)
+		t.Error("Unexpected: ", fromYAML)
+	}
+}
+
+func TestBadInput(t *testing.T) {
+	bad := []string{
+		"1.2",
+		"1.2.3x",
+		"0x1.3.4",
+		"-1.2.3",
+		"1.2.3.4",
+	}
+	for _, b := range bad {
+		if _, err := NewVersion(b); err == nil {
+			t.Error("Improperly accepted value: ", b)
+		}
+	}
+}
+
+func TestFlag(t *testing.T) {
+	v := Version{}
+	f := flag.NewFlagSet("version", flag.ContinueOnError)
+	f.Var(&v, "version", "set version")
+
+	if err := f.Set("version", "1.2.3"); err != nil {
+		t.Fatal(err)
+	}
+
+	if v.String() != "1.2.3" {
+		t.Errorf("Set wrong value %q", v)
+	}
+}
+
+func ExampleVersion_LessThan() {
+	vA := New("1.2.3")
+	vB := New("3.2.1")
+
+	fmt.Printf("%s < %s == %t\n", vA, vB, vA.LessThan(*vB))
+	// Output:
+	// 1.2.3 < 3.2.1 == true
+}

vendor/github.com/coreos/go-semver/semver/sort.go

@@ -0,0 +1,38 @@
+// Copyright 2013-2015 CoreOS, 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 semver
+
+import (
+	"sort"
+)
+
+type Versions []*Version
+
+func (s Versions) Len() int {
+	return len(s)
+}
+
+func (s Versions) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s Versions) Less(i, j int) bool {
+	return s[i].LessThan(*s[j])
+}
+
+// Sort sorts the given slice of Version
+func Sort(versions []*Version) {
+	sort.Sort(Versions(versions))
+}