feat: add OAuth2 support

Resolves #76

Signed-off-by: Romain Beuque <556072+rbeuque74@users.noreply.github.com>

go.mod

@@ -5,12 +5,17 @@ go 1.18
 require (
 	github.com/jarcoal/httpmock v1.3.0
 	github.com/maxatome/go-testdeep v1.12.0
+	golang.org/x/oauth2 v0.15.0
 	gopkg.in/ini.v1 v1.67.0
 )
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/stretchr/testify v1.8.2 // indirect
+	golang.org/x/net v0.19.0 // indirect
+	google.golang.org/appengine v1.6.7 // indirect
+	google.golang.org/protobuf v1.31.0 // indirect
 )
 
 retract (

go.sum

@@ -1,6 +1,12 @@
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
+github.com/golang/protobuf v1.5.3 h1:KhyjKVUg7Usr/dYsdSqoFveMYd5ko72D+zANwlG1mmg=
+github.com/golang/protobuf v1.5.3/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
+github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
 github.com/jarcoal/httpmock v1.3.0 h1:2RJ8GP0IIaWwcC9Fp2BmVi8Kog3v2Hn7VXM3fTd+nuc=
 github.com/jarcoal/httpmock v1.3.0/go.mod h1:3yb8rc4BI7TCBhFY8ng0gjuLKJNquuDNiPaZjnENuYg=
 github.com/maxatome/go-testdeep v1.12.0 h1:Ql7Go8Tg0C1D/uMMX59LAoYK7LffeJQ6X2T04nTH68g=
@@ -14,6 +20,23 @@ github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.2 h1:+h33VjcLVPDHtOdpUCuF+7gSuG3yGIftsP1YvFihtJ8=
 github.com/stretchr/testify v1.8.2/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/net v0.0.0-20190603091049-60506f45cf65/go.mod h1:HSz+uSET+XFnRR8LxR5pz3Of3rY3CfYBVs4xY44aLks=
+golang.org/x/net v0.19.0 h1:zTwKpTd2XuCqf8huc7Fo2iSy+4RHPd10s4KzeTnVr1c=
+golang.org/x/net v0.19.0/go.mod h1:CfAk/cbD4CthTvqiEl8NpboMuiuOYsAr/7NOjZJtv1U=
+golang.org/x/oauth2 v0.15.0 h1:s8pnnxNVzjWyrvYdFUQq5llS1PX2zhPXmccZv99h7uQ=
+golang.org/x/oauth2 v0.15.0/go.mod h1:q48ptWNTY5XWf+JNten23lcvHpLJ0ZSxF5ttTHKVCAM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/appengine v1.6.7 h1:FZR1q0exgwxzPzp/aF+VccGrSfxfPpkBqjIIEq3ru6c=
+google.golang.org/appengine v1.6.7/go.mod h1:8WjMMxjGQR8xUklV/ARdw2HLXBOI7O7uCIDZVag1xfc=
+google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
+google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
+google.golang.org/protobuf v1.31.0 h1:g0LDEJHgrBl9N9r17Ru3sqWhkIx2NB67okBHPwC7hs8=
+google.golang.org/protobuf v1.31.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/ini.v1 v1.67.0 h1:Dgnx+6+nfE+IfzjUEISNeydPJh9AXNNsWbGP9KzCsOA=
 gopkg.in/ini.v1 v1.67.0/go.mod h1:pNLf8WUiyNEtQjuu5G5vTm06TEv9tsIgeAvK8hOrP4k=

ovh/configuration.go

@@ -1,11 +1,13 @@
 package ovh
 
 import (
+	"context"
 	"fmt"
 	"os"
 	"os/user"
 	"strings"
 
+	"golang.org/x/oauth2/clientcredentials"
 	"gopkg.in/ini.v1"
 )
 
@@ -71,6 +73,11 @@ func loadINI() (*ini.File, error) {
 	return ini.LooseLoad(paths[0], paths[1:]...)
 }
 
+const (
+	authenticationModeOAuth2 = "oauth2"
+	authenticationModeOVH    = "ak-as-ck"
+)
+
 // loadConfig loads client configuration from params, environments or configuration
 // files (by order of decreasing precedence).
 //
@@ -114,24 +121,71 @@ func (c *Client) loadConfig(endpointName string) error {
 		c.ConsumerKey = getConfigValue(cfg, endpointName, "consumer_key", "")
 	}
 
+	if c.ClientID == "" {
+		c.ClientID = getConfigValue(cfg, endpointName, "client_id", "")
+	}
+
+	if c.ClientSecret == "" {
+		c.ClientSecret = getConfigValue(cfg, endpointName, "client_secret", "")
+	}
+
+	if c.ClientID != "" && c.ClientSecret != "" && c.AppKey != "" && c.AppSecret != "" {
+		return fmt.Errorf("can't use application_key/application_secret at the same time than OAuth2 client_id/client_secret")
+	}
+
 	// Load real endpoint URL by name. If endpoint contains a '/', consider it as a URL
 	if strings.Contains(endpointName, "/") {
 		c.endpoint = endpointName
 	} else {
 		c.endpoint = Endpoints[endpointName]
 	}
 
+	if c.ClientID != "" && c.ClientSecret != "" {
+		c.AppKey, c.AppSecret, c.ConsumerKey = "", "", ""
+		c.authenticationMode = authenticationModeOAuth2
+		if _, ok := tokensURLs[c.endpoint]; !ok {
+			return fmt.Errorf("oauth2 authentication is not compatible with endpoint %q", c.endpoint)
+		}
+	}
+
+	if c.AppKey != "" || c.AppSecret != "" {
+		c.ClientID, c.ClientSecret = "", ""
+		c.authenticationMode = authenticationModeOVH
+	}
+
+	if c.authenticationMode == "" {
+		return fmt.Errorf("missing authentication information, you need to provide at least an application_key/application_secret or a client_id/client_secret")
+	}
+
 	// If we still have no valid endpoint, AppKey or AppSecret, return an error
 	if c.endpoint == "" {
-		return fmt.Errorf("unknown endpoint '%s', consider checking 'Endpoints' list of using an URL", endpointName)
+		return fmt.Errorf("unknown endpoint '%s', consider checking 'Endpoints' list or using an URL", endpointName)
 	}
-	if c.AppKey == "" {
+	if c.AppKey == "" && c.authenticationMode == authenticationModeOVH {
 		return fmt.Errorf("missing application key, please check your configuration or consult the documentation to create one")
 	}
-	if c.AppSecret == "" {
+	if c.AppSecret == "" && c.authenticationMode == authenticationModeOVH {
 		return fmt.Errorf("missing application secret, please check your configuration or consult the documentation to create one")
 	}
 
+	if c.ClientID == "" && c.authenticationMode == authenticationModeOAuth2 {
+		return fmt.Errorf("missing client_id, please check your configuration or consult the documentation to create one")
+	}
+	if c.ClientSecret == "" && c.authenticationMode == authenticationModeOAuth2 {
+		return fmt.Errorf("missing client_secret, please check your configuration or consult the documentation to create one")
+	}
+
+	if c.authenticationMode == authenticationModeOAuth2 {
+		conf := &clientcredentials.Config{
+			ClientID:     c.ClientID,
+			ClientSecret: c.ClientSecret,
+			TokenURL:     tokensURLs[c.endpoint],
+			Scopes:       []string{"all"},
+		}
+
+		c.oauth2TokenSource = conf.TokenSource(context.Background())
+	}
+
 	return nil
 }
 

ovh/configuration_test.go

@@ -10,6 +10,8 @@ const (
 	systemConf       = "testdata/system.ini"
 	userPartialConf  = "testdata/userPartial.ini"
 	userConf         = "testdata/user.ini"
+	userOAuth2Conf   = "testdata/user_oauth2.ini"
+	userBothConf     = "testdata/user_both.ini"
 	localPartialConf = "testdata/localPartial.ini"
 	localWithURLConf = "testdata/localWithURL.ini"
 	doesNotExistConf = "testdata/doesNotExist.ini"
@@ -60,7 +62,7 @@ func TestConfigFromNonExistingFile(t *testing.T) {
 
 	client := Client{}
 	err := client.loadConfig("ovh-eu")
-	td.CmpString(t, err, `missing application key, please check your configuration or consult the documentation to create one`)
+	td.CmpString(t, err, `missing authentication information, you need to provide at least an application_key/application_secret or a client_id/client_secret`)
 }
 
 func TestConfigFromInvalidINIFile(t *testing.T) {
@@ -139,7 +141,7 @@ func TestMissingParam(t *testing.T) {
 
 	client.endpoint = ""
 	err := client.loadConfig("")
-	td.CmpString(t, err, `unknown endpoint '', consider checking 'Endpoints' list of using an URL`)
+	td.CmpString(t, err, `unknown endpoint '', consider checking 'Endpoints' list or using an URL`)
 
 	client.AppKey = ""
 	err = client.loadConfig("ovh-eu")
@@ -163,3 +165,23 @@ func TestConfigPaths(t *testing.T) {
 		[]interface{}{"", "file", "file.ini", "dir/file.ini", home + "/file.ini", "~typo.ini"},
 	)
 }
+
+func TestConfigOAuth2(t *testing.T) {
+	setConfigPaths(t, userOAuth2Conf)
+
+	client := Client{}
+	err := client.loadConfig("ovh-eu")
+	td.Require(t).CmpNoError(err)
+	td.Cmp(t, client, td.Struct(Client{
+		ClientID:     "foo",
+		ClientSecret: "bar",
+	}))
+}
+
+func TestConfigInvalidBoth(t *testing.T) {
+	setConfigPaths(t, userBothConf)
+
+	client := Client{}
+	err := client.loadConfig("ovh-eu")
+	td.Require(t).CmpError(err, "can't use application_key/application_secret at the same time than OAuth2 client_id/client_secret")
+}

ovh/ovh.go

@@ -14,6 +14,8 @@ import (
 	"strings"
 	"sync/atomic"
 	"time"
+
+	"golang.org/x/oauth2"
 )
 
 // getLocalTime is a function to be overwritten during the tests, it returns the time
@@ -48,6 +50,12 @@ var Endpoints = map[string]string{
 // Errors
 var (
 	ErrAPIDown = errors.New("go-ovh: the OVH API is not reachable: failed to get /auth/time response")
+
+	tokensURLs = map[string]string{
+		OvhEU: "https://www.ovh.com/auth/oauth2/token",
+		OvhCA: "https://ca.ovh.com/auth/oauth2/token",
+		OvhUS: "https://us.ovhcloud.com/auth/oauth2/token",
+	}
 )
 
 // Client represents a client to call the OVH API
@@ -63,8 +71,13 @@ type Client struct {
 	// ConsumerKey holds the user/app specific token. It must have been validated before use.
 	ConsumerKey string
 
+	ClientID     string
+	ClientSecret string
+
 	// API endpoint
-	endpoint string
+	endpoint           string
+	authenticationMode string
+	oauth2TokenSource  oauth2.TokenSource
 
 	// Client is the underlying HTTP client used to run the requests. It may be overloaded but a default one is instanciated in ``NewClient`` by default.
 	Client *http.Client
@@ -114,6 +127,21 @@ func NewDefaultClient() (*Client, error) {
 	return NewClient("", "", "", "")
 }
 
+func NewOAuth2Client(endpoint, clientID, clientSecret string) (*Client, error) {
+	client := Client{
+		ClientID:     clientID,
+		ClientSecret: clientSecret,
+		Client:       &http.Client{},
+		Timeout:      DefaultTimeout,
+	}
+
+	// Get and check the configuration
+	if err := client.loadConfig(endpoint); err != nil {
+		return nil, err
+	}
+	return &client, nil
+}
+
 func (c *Client) Endpoint() string {
 	return c.endpoint
 }
@@ -288,12 +316,14 @@ func (c *Client) NewRequest(method, path string, reqBody interface{}, needAuth b
 	if body != nil {
 		req.Header.Add("Content-Type", "application/json;charset=utf-8")
 	}
-	req.Header.Add("X-Ovh-Application", c.AppKey)
+	if c.authenticationMode == authenticationModeOVH {
+		req.Header.Add("X-Ovh-Application", c.AppKey)
+	}
 	req.Header.Add("Accept", "application/json")
 
 	// Inject signature. Some methods do not need authentication, especially /time,
 	// /auth and some /order methods are actually broken if authenticated.
-	if needAuth {
+	if needAuth && c.authenticationMode == authenticationModeOVH {
 		timeDelta, err := c.TimeDelta()
 		if err != nil {
 			return nil, err
@@ -314,6 +344,13 @@ func (c *Client) NewRequest(method, path string, reqBody interface{}, needAuth b
 			timestamp,
 		)))
 		req.Header.Add("X-Ovh-Signature", fmt.Sprintf("$1$%x", h.Sum(nil)))
+	} else if needAuth && c.authenticationMode == authenticationModeOAuth2 {
+		token, err := c.oauth2TokenSource.Token()
+		if err != nil {
+			return nil, err
+		}
+
+		req.Header.Set("Authorization", "Bearer "+token.AccessToken)
 	}
 
 	// Send the request with requested timeout

ovh/ovh_test.go

@@ -404,7 +404,7 @@ func TestConstructors(t *testing.T) {
 	// Error: missing Endpoint
 	client, err := NewClient("", MockApplicationKey, MockApplicationSecret, MockConsumerKey)
 	assert.Nil(client)
-	assert.String(err, `unknown endpoint '', consider checking 'Endpoints' list of using an URL`)
+	assert.String(err, `unknown endpoint '', consider checking 'Endpoints' list or using an URL`)
 
 	// Error: missing ApplicationKey
 	client, err = NewClient("ovh-eu", "", MockApplicationSecret, MockConsumerKey)

ovh/testdata/user_both.ini

@@ -0,0 +1,5 @@
+[ovh-eu]
+application_key=user
+application_secret=user
+client_id=foo
+client_secret=bar

ovh/testdata/user_oauth2.ini

@@ -0,0 +1,3 @@
+[ovh-eu]
+client_id=foo
+client_secret=bar