V2 API Version Support

* Update blang/semver to allow ParseTolerant() support
* Provide helper functions for API handlers to obtain client's 'version'
  path variable focused on API endpoint tree: libpod vs. compat
* Introduce new errors:
  * version not given in path, endpoints may determine if this is a hard
    error (ErrVersionNotGiven)
  * given version not supported (ErrVersionNotSupported), only a soft
    error if the handler is going to hijack the connection
* Added unit tests for version parsing
* bindings check version on connect:
  * client <= Server API version connection is continued
  * client >= Server API version connection fails

Signed-off-by: Jhon Honce <jhonce@redhat.com>

17 files changed, 544 insertions, 49 deletions

diff --git a/go.mod b/go.mod
index aac3f4c6f..3160186aa 100644
--- a/go.mod
+++ b/go.mod
@@ -4,6 +4,7 @@ go 1.12
 
 require (
 	github.com/BurntSushi/toml v0.3.1
+	github.com/blang/semver v3.5.1+incompatible
 	github.com/buger/goterm v0.0.0-20181115115552-c206103e1f37
 	github.com/checkpoint-restore/go-criu v0.0.0-20190109184317-bdb7599cd87b
 	github.com/codahale/hdrhistogram v0.0.0-20161010025455-3a0bb77429bd // indirect
diff --git a/go.sum b/go.sum
index 9a89453e1..e5d967b7d 100644
--- a/go.sum
+++ b/go.sum
@@ -39,6 +39,8 @@ github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
 github.com/blang/semver v3.1.0+incompatible h1:7hqmJYuaEK3qwVjWubYiht3j93YI0WQBuysxHIfUriU=
 github.com/blang/semver v3.1.0+incompatible/go.mod h1:kRBLl5iJ+tD4TcOOxsy/0fnwebNt5EWlYSAyrTnjyyk=
+github.com/blang/semver v3.5.1+incompatible h1:cQNTCjp13qL8KC3Nbxr/y2Bqb63oX6wdnnjpJbkM4JQ=
+github.com/blang/semver v3.5.1+incompatible/go.mod h1:kRBLl5iJ+tD4TcOOxsy/0fnwebNt5EWlYSAyrTnjyyk=
 github.com/buger/goterm v0.0.0-20181115115552-c206103e1f37 h1:uxxtrnACqI9zK4ENDMf0WpXfUsHP5V8liuq5QdgDISU=
 github.com/buger/goterm v0.0.0-20181115115552-c206103e1f37/go.mod h1:u9UyCz2eTrSGy6fbupqJ54eY5c4IC8gREQ1053dK12U=
 github.com/buger/jsonparser v0.0.0-20180808090653-f4dd9f5a6b44/go.mod h1:bbYlZJ7hK1yFx9hf58LP0zeX7UjIGs20ufpu3evjr+s=
diff --git a/pkg/api/handlers/compat/ping.go b/pkg/api/handlers/compat/ping.go
index 6e77e270f..abee3d8e8 100644
--- a/pkg/api/handlers/compat/ping.go
+++ b/pkg/api/handlers/compat/ping.go
@@ -5,22 +5,22 @@ import (
 	"net/http"
 
 	"github.com/containers/buildah"
-	"github.com/containers/libpod/pkg/api/handlers"
+	"github.com/containers/libpod/pkg/api/handlers/utils"
 )
 
 // Ping returns headers to client about the service
 //
 // This handler must always be the same for the compatibility and libpod URL trees!
 // Clients will use the Header availability to test which backend engine is in use.
+// Note: Additionally handler supports GET and HEAD methods
 func Ping(w http.ResponseWriter, r *http.Request) {
-	w.Header().Set("API-Version", handlers.DefaultApiVersion)
+	w.Header().Set("API-Version", utils.ApiVersion[utils.CompatTree][utils.CurrentApiVersion].String())
 	w.Header().Set("BuildKit-Version", "")
 	w.Header().Set("Docker-Experimental", "true")
 	w.Header().Set("Cache-Control", "no-cache")
 	w.Header().Set("Pragma", "no-cache")
 
-	// API-Version and Libpod-API-Version may not always be equal
-	w.Header().Set("Libpod-API-Version", handlers.DefaultApiVersion)
+	w.Header().Set("Libpod-API-Version", utils.ApiVersion[utils.LibpodTree][utils.CurrentApiVersion].String())
 	w.Header().Set("Libpod-Buildha-Version", buildah.Version)
 	w.WriteHeader(http.StatusOK)
 
diff --git a/pkg/api/handlers/compat/version.go b/pkg/api/handlers/compat/version.go
index 8786f1d5b..bfc226bb8 100644
--- a/pkg/api/handlers/compat/version.go
+++ b/pkg/api/handlers/compat/version.go
@@ -8,7 +8,6 @@ import (
 
 	"github.com/containers/libpod/libpod"
 	"github.com/containers/libpod/libpod/define"
-	"github.com/containers/libpod/pkg/api/handlers"
 	"github.com/containers/libpod/pkg/api/handlers/utils"
 	"github.com/containers/libpod/pkg/domain/entities"
 	docker "github.com/docker/docker/api/types"
@@ -35,34 +34,35 @@ func VersionHandler(w http.ResponseWriter, r *http.Request) {
 		Name:    "Podman Engine",
 		Version: versionInfo.Version,
 		Details: map[string]string{
-			"APIVersion":    handlers.DefaultApiVersion,
+			"APIVersion":    utils.ApiVersion[utils.LibpodTree][utils.CurrentApiVersion].String(),
 			"Arch":          goRuntime.GOARCH,
 			"BuildTime":     time.Unix(versionInfo.Built, 0).Format(time.RFC3339),
 			"Experimental":  "true",
 			"GitCommit":     versionInfo.GitCommit,
 			"GoVersion":     versionInfo.GoVersion,
 			"KernelVersion": infoData.Host.Kernel,
-			"MinAPIVersion": handlers.MinimalApiVersion,
+			"MinAPIVersion": utils.ApiVersion[utils.LibpodTree][utils.MinimalApiVersion].String(),
 			"Os":            goRuntime.GOOS,
 		},
 	}}
 
-	utils.WriteResponse(w, http.StatusOK, entities.ComponentVersion{Version: docker.Version{
-		Platform: struct {
-			Name string
-		}{
-			Name: fmt.Sprintf("%s/%s/%s-%s", goRuntime.GOOS, goRuntime.GOARCH, infoData.Host.Distribution.Distribution, infoData.Host.Distribution.Version),
-		},
-		APIVersion:    components[0].Details["APIVersion"],
-		Arch:          components[0].Details["Arch"],
-		BuildTime:     components[0].Details["BuildTime"],
-		Components:    components,
-		Experimental:  true,
-		GitCommit:     components[0].Details["GitCommit"],
-		GoVersion:     components[0].Details["GoVersion"],
-		KernelVersion: components[0].Details["KernelVersion"],
-		MinAPIVersion: components[0].Details["MinAPIVersion"],
-		Os:            components[0].Details["Os"],
-		Version:       components[0].Version,
-	}})
+	utils.WriteResponse(w, http.StatusOK, entities.ComponentVersion{
+		Version: docker.Version{
+			Platform: struct {
+				Name string
+			}{
+				Name: fmt.Sprintf("%s/%s/%s-%s", goRuntime.GOOS, goRuntime.GOARCH, infoData.Host.Distribution.Distribution, infoData.Host.Distribution.Version),
+			},
+			APIVersion:    components[0].Details["APIVersion"],
+			Arch:          components[0].Details["Arch"],
+			BuildTime:     components[0].Details["BuildTime"],
+			Components:    components,
+			Experimental:  true,
+			GitCommit:     components[0].Details["GitCommit"],
+			GoVersion:     components[0].Details["GoVersion"],
+			KernelVersion: components[0].Details["KernelVersion"],
+			MinAPIVersion: components[0].Details["MinAPIVersion"],
+			Os:            components[0].Details["Os"],
+			Version:       components[0].Version,
+		}})
 }
diff --git a/pkg/api/handlers/handler.go b/pkg/api/handlers/handler.go
deleted file mode 100644
index 2dd2c886b..000000000
--- a/pkg/api/handlers/handler.go
+++ /dev/null
@@ -1,6 +0,0 @@
-package handlers
-
-const (
-	DefaultApiVersion = "1.40" // See https://docs.docker.com/engine/api/v1.40/
-	MinimalApiVersion = "1.24"
-)
diff --git a/pkg/api/handlers/utils/handler.go b/pkg/api/handlers/utils/handler.go
index b5bd488fb..2f4a54b98 100644
--- a/pkg/api/handlers/utils/handler.go
+++ b/pkg/api/handlers/utils/handler.go
@@ -9,11 +9,55 @@ import (
 	"os"
 	"strings"
 
+	"github.com/blang/semver"
 	"github.com/gorilla/mux"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 
+type (
+	// VersionTree determines which API endpoint tree for version
+	VersionTree int
+	// VersionLevel determines which API level, current or something from the past
+	VersionLevel int
+)
+
+const (
+	// LibpodTree supports Libpod endpoints
+	LibpodTree = VersionTree(iota)
+	// CompatTree supports Libpod endpoints
+	CompatTree
+
+	// CurrentApiVersion announces what is the current API level
+	CurrentApiVersion = VersionLevel(iota)
+	// MinimalApiVersion announces what is the oldest API level supported
+	MinimalApiVersion
+)
+
+var (
+	// See https://docs.docker.com/engine/api/v1.40/
+	// libpod compat handlers are expected to honor docker API versions
+
+	// ApiVersion provides the current and minimal API versions for compat and libpod endpoint trees
+	// Note: GET|HEAD /_ping is never versioned and provides the API-Version and Libpod-API-Version headers to allow
+	//       clients to shop for the Version they wish to support
+	ApiVersion = map[VersionTree]map[VersionLevel]semver.Version{
+		LibpodTree: {
+			CurrentApiVersion: semver.MustParse("1.0.0"),
+			MinimalApiVersion: semver.MustParse("1.0.0"),
+		},
+		CompatTree: {
+			CurrentApiVersion: semver.MustParse("1.40.0"),
+			MinimalApiVersion: semver.MustParse("1.24.0"),
+		},
+	}
+
+	// ErrVersionNotGiven returned when version not given by client
+	ErrVersionNotGiven = errors.New("version not given in URL path")
+	// ErrVersionNotSupported returned when given version is too old
+	ErrVersionNotSupported = errors.New("given version is not supported")
+)
+
 // IsLibpodRequest returns true if the request related to a libpod endpoint
 // (e.g., /v2/libpod/...).
 func IsLibpodRequest(r *http.Request) bool {
@@ -21,6 +65,48 @@ func IsLibpodRequest(r *http.Request) bool {
 	return len(split) >= 3 && split[2] == "libpod"
 }
 
+// SupportedVersion validates that the version provided by client is included in the given condition
+// https://github.com/blang/semver#ranges provides the details for writing conditions
+// If a version is not given in URL path, ErrVersionNotGiven is returned
+func SupportedVersion(r *http.Request, condition string) (semver.Version, error) {
+	version := semver.Version{}
+	val, ok := mux.Vars(r)["version"]
+	if !ok {
+		return version, ErrVersionNotGiven
+	}
+	safeVal, err := url.PathUnescape(val)
+	if err != nil {
+		return version, errors.Wrapf(err, "unable to unescape given API version: %q", val)
+	}
+	version, err = semver.ParseTolerant(safeVal)
+	if err != nil {
+		return version, errors.Wrapf(err, "unable to parse given API version: %q from %q", safeVal, val)
+	}
+
+	inRange, err := semver.ParseRange(condition)
+	if err != nil {
+		return version, err
+	}
+
+	if inRange(version) {
+		return version, nil
+	}
+	return version, ErrVersionNotSupported
+}
+
+// SupportedVersionWithDefaults validates that the version provided by client valid is supported by server
+// minimal API version <= client path version <= maximum API version focused on the endpoint tree from URL
+func SupportedVersionWithDefaults(r *http.Request) (semver.Version, error) {
+	tree := CompatTree
+	if IsLibpodRequest(r) {
+		tree = LibpodTree
+	}
+
+	return SupportedVersion(r,
+		fmt.Sprintf(">=%s <=%s", ApiVersion[tree][MinimalApiVersion].String(),
+			ApiVersion[tree][CurrentApiVersion].String()))
+}
+
 // WriteResponse encodes the given value as JSON or string and renders it for http client
 func WriteResponse(w http.ResponseWriter, code int, value interface{}) {
 	// RFC2616 explicitly states that the following status codes "MUST NOT
diff --git a/pkg/api/handlers/utils/handler_test.go b/pkg/api/handlers/utils/handler_test.go
new file mode 100644
index 000000000..6009432b5
--- /dev/null
+++ b/pkg/api/handlers/utils/handler_test.go
@@ -0,0 +1,139 @@
+package utils
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gorilla/mux"
+)
+
+func TestSupportedVersion(t *testing.T) {
+	req, err := http.NewRequest("GET",
+		fmt.Sprintf("/v%s/libpod/testing/versions", ApiVersion[LibpodTree][CurrentApiVersion]),
+		nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	req = mux.SetURLVars(req, map[string]string{"version": ApiVersion[LibpodTree][CurrentApiVersion].String()})
+
+	rr := httptest.NewRecorder()
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, err := SupportedVersionWithDefaults(r)
+		switch {
+		case errors.Is(err, ErrVersionNotGiven): // for compat endpoints version optional
+			w.WriteHeader(http.StatusInternalServerError)
+			fmt.Fprint(w, err.Error())
+		case errors.Is(err, ErrVersionNotSupported): // version given but not supported
+			w.WriteHeader(http.StatusBadRequest)
+			fmt.Fprint(w, err.Error())
+		case err != nil:
+			w.WriteHeader(http.StatusInternalServerError)
+			fmt.Fprint(w, err.Error())
+		default: // all good
+			w.WriteHeader(http.StatusOK)
+			fmt.Fprint(w, "OK")
+		}
+	})
+	handler.ServeHTTP(rr, req)
+
+	if status := rr.Code; status != http.StatusOK {
+		t.Errorf("handler returned wrong status code: got %v want %v",
+			status, http.StatusOK)
+	}
+
+	// Check the response body is what we expect.
+	expected := `OK`
+	if rr.Body.String() != expected {
+		t.Errorf("handler returned unexpected body: got %q want %q",
+			rr.Body.String(), expected)
+	}
+}
+
+func TestUnsupportedVersion(t *testing.T) {
+	version := "999.999.999"
+	req, err := http.NewRequest("GET",
+		fmt.Sprintf("/v%s/libpod/testing/versions", version),
+		nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	req = mux.SetURLVars(req, map[string]string{"version": version})
+
+	rr := httptest.NewRecorder()
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, err := SupportedVersionWithDefaults(r)
+		switch {
+		case errors.Is(err, ErrVersionNotGiven): // for compat endpoints version optional
+			w.WriteHeader(http.StatusInternalServerError)
+			fmt.Fprint(w, err.Error())
+		case errors.Is(err, ErrVersionNotSupported): // version given but not supported
+			w.WriteHeader(http.StatusBadRequest)
+			fmt.Fprint(w, err.Error())
+		case err != nil:
+			w.WriteHeader(http.StatusInternalServerError)
+			fmt.Fprint(w, err.Error())
+		default: // all good
+			w.WriteHeader(http.StatusOK)
+			fmt.Fprint(w, "OK")
+		}
+	})
+	handler.ServeHTTP(rr, req)
+
+	if status := rr.Code; status != http.StatusBadRequest {
+		t.Errorf("handler returned wrong status code: got %v want %v",
+			status, http.StatusBadRequest)
+	}
+
+	// Check the response body is what we expect.
+	expected := ErrVersionNotSupported.Error()
+	if rr.Body.String() != expected {
+		t.Errorf("handler returned unexpected body: got %q want %q",
+			rr.Body.String(), expected)
+	}
+}
+
+func TestEqualVersion(t *testing.T) {
+	version := "1.30.0"
+	req, err := http.NewRequest("GET",
+		fmt.Sprintf("/v%s/libpod/testing/versions", version),
+		nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	req = mux.SetURLVars(req, map[string]string{"version": version})
+
+	rr := httptest.NewRecorder()
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, err := SupportedVersion(r, "=="+version)
+		switch {
+		case errors.Is(err, ErrVersionNotGiven): // for compat endpoints version optional
+			w.WriteHeader(http.StatusInternalServerError)
+			fmt.Fprint(w, err.Error())
+		case errors.Is(err, ErrVersionNotSupported): // version given but not supported
+			w.WriteHeader(http.StatusBadRequest)
+			fmt.Fprint(w, err.Error())
+		case err != nil:
+			w.WriteHeader(http.StatusInternalServerError)
+			fmt.Fprint(w, err.Error())
+		default: // all good
+			w.WriteHeader(http.StatusOK)
+			fmt.Fprint(w, "OK")
+		}
+	})
+	handler.ServeHTTP(rr, req)
+
+	if status := rr.Code; status != http.StatusOK {
+		t.Errorf("handler returned wrong status code: got %v want %v",
+			status, http.StatusOK)
+	}
+
+	// Check the response body is what we expect.
+	expected := http.StatusText(http.StatusOK)
+	if rr.Body.String() != expected {
+		t.Errorf("handler returned unexpected body: got %q want %q",
+			rr.Body.String(), expected)
+	}
+}
diff --git a/pkg/bindings/bindings.go b/pkg/bindings/bindings.go
index 5e2882aae..7e2a444bd 100644
--- a/pkg/bindings/bindings.go
+++ b/pkg/bindings/bindings.go
@@ -8,6 +8,10 @@
 
 package bindings
 
+import (
+	"github.com/blang/semver"
+)
+
 var (
 	// PTrue is a convenience variable that can be used in bindings where
 	// a pointer to a bool (optional parameter) is required.
@@ -17,4 +21,7 @@ var (
 	// a pointer to a bool (optional parameter) is required.
 	pFalse = false
 	PFalse = &pFalse
+
+	// _*YES*- podman will fail to run if this value is wrong
+	APIVersion = semver.MustParse("1.0.0")
 )
diff --git a/pkg/bindings/connection.go b/pkg/bindings/connection.go
index d83c0482c..d21d55beb 100644
--- a/pkg/bindings/connection.go
+++ b/pkg/bindings/connection.go
@@ -15,6 +15,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/blang/semver"
 	"github.com/containers/libpod/pkg/api/types"
 	jsoniter "github.com/json-iterator/go"
 	"github.com/pkg/errors"
@@ -143,7 +144,7 @@ func tcpClient(_url *url.URL) (Connection, error) {
 }
 
 // pingNewConnection pings to make sure the RESTFUL service is up
-// and running. it should only be used where initializing a connection
+// and running. it should only be used when initializing a connection
 func pingNewConnection(ctx context.Context) error {
 	client, err := GetClient(ctx)
 	if err != nil {
@@ -154,8 +155,20 @@ func pingNewConnection(ctx context.Context) error {
 	if err != nil {
 		return err
 	}
+
 	if response.StatusCode == http.StatusOK {
-		return nil
+		v, err := semver.ParseTolerant(response.Header.Get("Libpod-API-Version"))
+		if err != nil {
+			return err
+		}
+
+		switch APIVersion.Compare(v) {
+		case 1, 0:
+			// Server's job when client version is equal or older
+			return nil
+		case -1:
+			return errors.Errorf("server API version is too old. client %q server %q", APIVersion.String(), v.String())
+		}
 	}
 	return errors.Errorf("ping response was %q", response.StatusCode)
 }
diff --git a/pkg/bindings/version.go b/pkg/bindings/version.go
deleted file mode 100644
index c833a644c..000000000
--- a/pkg/bindings/version.go
+++ /dev/null
@@ -1,3 +0,0 @@
-package bindings
-
-func (c Connection) Version() {}
diff --git a/test/apiv2/01-basic.at b/test/apiv2/01-basic.at
index 0e94ddb7a..18ec9bbe8 100644
--- a/test/apiv2/01-basic.at
+++ b/test/apiv2/01-basic.at
@@ -10,13 +10,13 @@ t HEAD /_ping        200
 t GET  /libpod/_ping 200 OK
 
 for i in /version version; do
-    t GET  $i      200                    \
-      .Components[0].Name="Podman Engine"       \
-      .Components[0].Details.APIVersion=1.40    \
-      .Components[0].Details.MinAPIVersion=1.24 \
-      .Components[0].Details.Os=linux           \
-      .ApiVersion=1.40                          \
-      .MinAPIVersion=1.24                       \
+    t GET  $i      200                           \
+      .Components[0].Name="Podman Engine"        \
+      .Components[0].Details.APIVersion=1.0.0    \
+      .Components[0].Details.MinAPIVersion=1.0.0 \
+      .Components[0].Details.Os=linux            \
+      .ApiVersion=1.0.0                          \
+      .MinAPIVersion=1.0.0                       \
       .Os=linux
 done
 
diff --git a/vendor/github.com/blang/semver/.travis.yml b/vendor/github.com/blang/semver/.travis.yml
new file mode 100644
index 000000000..102fb9a69
--- /dev/null
+++ b/vendor/github.com/blang/semver/.travis.yml
@@ -0,0 +1,21 @@
+language: go
+matrix:
+  include:
+  - go: 1.4.3
+  - go: 1.5.4
+  - go: 1.6.3
+  - go: 1.7
+  - go: tip
+  allow_failures:
+  - go: tip
+install:
+- go get golang.org/x/tools/cmd/cover
+- go get github.com/mattn/goveralls
+script:
+- echo "Test and track coverage" ; $HOME/gopath/bin/goveralls -package "." -service=travis-ci
+  -repotoken $COVERALLS_TOKEN
+- echo "Build examples" ; cd examples && go build
+- echo "Check if gofmt'd" ; diff -u <(echo -n) <(gofmt -d -s .)
+env:
+  global:
+    secure: HroGEAUQpVq9zX1b1VIkraLiywhGbzvNnTZq2TMxgK7JHP8xqNplAeF1izrR2i4QLL9nsY+9WtYss4QuPvEtZcVHUobw6XnL6radF7jS1LgfYZ9Y7oF+zogZ2I5QUMRLGA7rcxQ05s7mKq3XZQfeqaNts4bms/eZRefWuaFZbkw=
diff --git a/vendor/github.com/blang/semver/README.md b/vendor/github.com/blang/semver/README.md
index 4399639e2..08b2e4a3d 100644
--- a/vendor/github.com/blang/semver/README.md
+++ b/vendor/github.com/blang/semver/README.md
@@ -1,4 +1,4 @@
-semver for golang [![Build Status](https://drone.io/github.com/blang/semver/status.png)](https://drone.io/github.com/blang/semver/latest) [![GoDoc](https://godoc.org/github.com/blang/semver?status.png)](https://godoc.org/github.com/blang/semver) [![Coverage Status](https://img.shields.io/coveralls/blang/semver.svg)](https://coveralls.io/r/blang/semver?branch=master)
+semver for golang [![Build Status](https://travis-ci.org/blang/semver.svg?branch=master)](https://travis-ci.org/blang/semver) [![GoDoc](https://godoc.org/github.com/blang/semver?status.png)](https://godoc.org/github.com/blang/semver) [![Coverage Status](https://img.shields.io/coveralls/blang/semver.svg)](https://coveralls.io/r/blang/semver?branch=master)
 ======
 
 semver is a [Semantic Versioning](http://semver.org/) library written in golang. It fully covers spec version `2.0.0`.
@@ -41,6 +41,7 @@ Features
 - Compare Helper Methods
 - InPlace manipulation
 - Ranges `>=1.0.0 <2.0.0 || >=3.0.0 !3.0.1-beta.1`
+- Wildcards `>=1.x`, `<=2.5.x`
 - Sortable (implements sort.Interface)
 - database/sql compatible (sql.Scanner/Valuer)
 - encoding/json compatible (json.Marshaler/Unmarshaler)
@@ -59,6 +60,8 @@ A condition is composed of an operator and a version. The supported operators ar
 - `1.0.0`, `=1.0.0`, `==1.0.0` Equal to `1.0.0`
 - `!1.0.0`, `!=1.0.0` Not equal to `1.0.0`. Excludes version `1.0.0`.
 
+Note that spaces between the operator and the version will be gracefully tolerated.
+
 A `Range` can link multiple `Ranges` separated by space:
 
 Ranges can be linked by logical AND:
diff --git a/vendor/github.com/blang/semver/package.json b/vendor/github.com/blang/semver/package.json
new file mode 100644
index 000000000..1cf8ebdd9
--- /dev/null
+++ b/vendor/github.com/blang/semver/package.json
@@ -0,0 +1,17 @@
+{
+  "author": "blang",
+  "bugs": {
+    "URL": "https://github.com/blang/semver/issues",
+    "url": "https://github.com/blang/semver/issues"
+  },
+  "gx": {
+    "dvcsimport": "github.com/blang/semver"
+  },
+  "gxVersion": "0.10.0",
+  "language": "go",
+  "license": "MIT",
+  "name": "semver",
+  "releaseCmd": "git commit -a -m \"gx publish $VERSION\"",
+  "version": "3.5.1"
+}
+
diff --git a/vendor/github.com/blang/semver/range.go b/vendor/github.com/blang/semver/range.go
index 0a8eaa1c9..fca406d47 100644
--- a/vendor/github.com/blang/semver/range.go
+++ b/vendor/github.com/blang/semver/range.go
@@ -2,10 +2,33 @@ package semver
 
 import (
 	"fmt"
+	"strconv"
 	"strings"
 	"unicode"
 )
 
+type wildcardType int
+
+const (
+	noneWildcard  wildcardType = iota
+	majorWildcard wildcardType = 1
+	minorWildcard wildcardType = 2
+	patchWildcard wildcardType = 3
+)
+
+func wildcardTypefromInt(i int) wildcardType {
+	switch i {
+	case 1:
+		return majorWildcard
+	case 2:
+		return minorWildcard
+	case 3:
+		return patchWildcard
+	default:
+		return noneWildcard
+	}
+}
+
 type comparator func(Version, Version) bool
 
 var (
@@ -92,8 +115,12 @@ func ParseRange(s string) (Range, error) {
 	if err != nil {
 		return nil, err
 	}
+	expandedParts, err := expandWildcardVersion(orParts)
+	if err != nil {
+		return nil, err
+	}
 	var orFn Range
-	for _, p := range orParts {
+	for _, p := range expandedParts {
 		var andFn Range
 		for _, ap := range p {
 			opStr, vStr, err := splitComparatorVersion(ap)
@@ -164,20 +191,39 @@ func buildVersionRange(opStr, vStr string) (*versionRange, error) {
 
 }
 
-// splitAndTrim splits a range string by spaces and cleans leading and trailing spaces
+// inArray checks if a byte is contained in an array of bytes
+func inArray(s byte, list []byte) bool {
+	for _, el := range list {
+		if el == s {
+			return true
+		}
+	}
+	return false
+}
+
+// splitAndTrim splits a range string by spaces and cleans whitespaces
 func splitAndTrim(s string) (result []string) {
 	last := 0
+	var lastChar byte
+	excludeFromSplit := []byte{'>', '<', '='}
 	for i := 0; i < len(s); i++ {
-		if s[i] == ' ' {
+		if s[i] == ' ' && !inArray(lastChar, excludeFromSplit) {
 			if last < i-1 {
 				result = append(result, s[last:i])
 			}
 			last = i + 1
+		} else if s[i] != ' ' {
+			lastChar = s[i]
 		}
 	}
 	if last < len(s)-1 {
 		result = append(result, s[last:])
 	}
+
+	for i, v := range result {
+		result[i] = strings.Replace(v, " ", "", -1)
+	}
+
 	// parts := strings.Split(s, " ")
 	// for _, x := range parts {
 	// 	if s := strings.TrimSpace(x); len(s) != 0 {
@@ -188,7 +234,6 @@ func splitAndTrim(s string) (result []string) {
 }
 
 // splitComparatorVersion splits the comparator from the version.
-// Spaces between the comparator and the version are not allowed.
 // Input must be free of leading or trailing spaces.
 func splitComparatorVersion(s string) (string, string, error) {
 	i := strings.IndexFunc(s, unicode.IsDigit)
@@ -198,6 +243,144 @@ func splitComparatorVersion(s string) (string, string, error) {
 	return strings.TrimSpace(s[0:i]), s[i:], nil
 }
 
+// getWildcardType will return the type of wildcard that the
+// passed version contains
+func getWildcardType(vStr string) wildcardType {
+	parts := strings.Split(vStr, ".")
+	nparts := len(parts)
+	wildcard := parts[nparts-1]
+
+	possibleWildcardType := wildcardTypefromInt(nparts)
+	if wildcard == "x" {
+		return possibleWildcardType
+	}
+
+	return noneWildcard
+}
+
+// createVersionFromWildcard will convert a wildcard version
+// into a regular version, replacing 'x's with '0's, handling
+// special cases like '1.x.x' and '1.x'
+func createVersionFromWildcard(vStr string) string {
+	// handle 1.x.x
+	vStr2 := strings.Replace(vStr, ".x.x", ".x", 1)
+	vStr2 = strings.Replace(vStr2, ".x", ".0", 1)
+	parts := strings.Split(vStr2, ".")
+
+	// handle 1.x
+	if len(parts) == 2 {
+		return vStr2 + ".0"
+	}
+
+	return vStr2
+}
+
+// incrementMajorVersion will increment the major version
+// of the passed version
+func incrementMajorVersion(vStr string) (string, error) {
+	parts := strings.Split(vStr, ".")
+	i, err := strconv.Atoi(parts[0])
+	if err != nil {
+		return "", err
+	}
+	parts[0] = strconv.Itoa(i + 1)
+
+	return strings.Join(parts, "."), nil
+}
+
+// incrementMajorVersion will increment the minor version
+// of the passed version
+func incrementMinorVersion(vStr string) (string, error) {
+	parts := strings.Split(vStr, ".")
+	i, err := strconv.Atoi(parts[1])
+	if err != nil {
+		return "", err
+	}
+	parts[1] = strconv.Itoa(i + 1)
+
+	return strings.Join(parts, "."), nil
+}
+
+// expandWildcardVersion will expand wildcards inside versions
+// following these rules:
+//
+// * when dealing with patch wildcards:
+// >= 1.2.x    will become    >= 1.2.0
+// <= 1.2.x    will become    <  1.3.0
+// >  1.2.x    will become    >= 1.3.0
+// <  1.2.x    will become    <  1.2.0
+// != 1.2.x    will become    <  1.2.0 >= 1.3.0
+//
+// * when dealing with minor wildcards:
+// >= 1.x      will become    >= 1.0.0
+// <= 1.x      will become    <  2.0.0
+// >  1.x      will become    >= 2.0.0
+// <  1.0      will become    <  1.0.0
+// != 1.x      will become    <  1.0.0 >= 2.0.0
+//
+// * when dealing with wildcards without
+// version operator:
+// 1.2.x       will become    >= 1.2.0 < 1.3.0
+// 1.x         will become    >= 1.0.0 < 2.0.0
+func expandWildcardVersion(parts [][]string) ([][]string, error) {
+	var expandedParts [][]string
+	for _, p := range parts {
+		var newParts []string
+		for _, ap := range p {
+			if strings.Index(ap, "x") != -1 {
+				opStr, vStr, err := splitComparatorVersion(ap)
+				if err != nil {
+					return nil, err
+				}
+
+				versionWildcardType := getWildcardType(vStr)
+				flatVersion := createVersionFromWildcard(vStr)
+
+				var resultOperator string
+				var shouldIncrementVersion bool
+				switch opStr {
+				case ">":
+					resultOperator = ">="
+					shouldIncrementVersion = true
+				case ">=":
+					resultOperator = ">="
+				case "<":
+					resultOperator = "<"
+				case "<=":
+					resultOperator = "<"
+					shouldIncrementVersion = true
+				case "", "=", "==":
+					newParts = append(newParts, ">="+flatVersion)
+					resultOperator = "<"
+					shouldIncrementVersion = true
+				case "!=", "!":
+					newParts = append(newParts, "<"+flatVersion)
+					resultOperator = ">="
+					shouldIncrementVersion = true
+				}
+
+				var resultVersion string
+				if shouldIncrementVersion {
+					switch versionWildcardType {
+					case patchWildcard:
+						resultVersion, _ = incrementMinorVersion(flatVersion)
+					case minorWildcard:
+						resultVersion, _ = incrementMajorVersion(flatVersion)
+					}
+				} else {
+					resultVersion = flatVersion
+				}
+
+				ap = resultOperator + resultVersion
+			}
+			newParts = append(newParts, ap)
+		}
+		expandedParts = append(expandedParts, newParts)
+	}
+
+	return expandedParts, nil
+}
+
 func parseComparator(s string) comparator {
 	switch s {
 	case "==":
@@ -222,3 +405,12 @@ func parseComparator(s string) comparator {
 
 	return nil
 }
+
+// MustParseRange is like ParseRange but panics if the range cannot be parsed.
+func MustParseRange(s string) Range {
+	r, err := ParseRange(s)
+	if err != nil {
+		panic(`semver: ParseRange(` + s + `): ` + err.Error())
+	}
+	return r
+}
diff --git a/vendor/github.com/blang/semver/semver.go b/vendor/github.com/blang/semver/semver.go
index bbf85ce97..8ee0842e6 100644
--- a/vendor/github.com/blang/semver/semver.go
+++ b/vendor/github.com/blang/semver/semver.go
@@ -200,6 +200,29 @@ func Make(s string) (Version, error) {
 	return Parse(s)
 }
 
+// ParseTolerant allows for certain version specifications that do not strictly adhere to semver
+// specs to be parsed by this library. It does so by normalizing versions before passing them to
+// Parse(). It currently trims spaces, removes a "v" prefix, and adds a 0 patch number to versions
+// with only major and minor components specified
+func ParseTolerant(s string) (Version, error) {
+	s = strings.TrimSpace(s)
+	s = strings.TrimPrefix(s, "v")
+
+	// Split into major.minor.(patch+pr+meta)
+	parts := strings.SplitN(s, ".", 3)
+	if len(parts) < 3 {
+		if strings.ContainsAny(parts[len(parts)-1], "+-") {
+			return Version{}, errors.New("Short version cannot contain PreRelease/Build meta data")
+		}
+		for len(parts) < 3 {
+			parts = append(parts, "0")
+		}
+		s = strings.Join(parts, ".")
+	}
+
+	return Parse(s)
+}
+
 // Parse parses version string and returns a validated Version or error
 func Parse(s string) (Version, error) {
 	if len(s) == 0 {
diff --git a/vendor/modules.txt b/vendor/modules.txt
index f3d216559..9159143c4 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -34,7 +34,7 @@ github.com/VividCortex/ewma
 github.com/acarl005/stripansi
 # github.com/beorn7/perks v1.0.1
 github.com/beorn7/perks/quantile
-# github.com/blang/semver v3.1.0+incompatible
+# github.com/blang/semver v3.5.1+incompatible
 github.com/blang/semver
 # github.com/buger/goterm v0.0.0-20181115115552-c206103e1f37
 github.com/buger/goterm