feat: added oauthutils package (#395)

pkg/common/oauth2/discovery.go

@@ -0,0 +1,98 @@
+package oauthutils
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+)
+
+// OauthLocationGetter is used to get the location parameters
+// used in an oauth flow
+type OauthLocationGetter interface {
+	// Discover is responsible for determining the parameters used for an oauth flow
+	// and returns them as a OauthDiscoveryResult
+	Discover(ctx context.Context, discoveryURL string) (*OauthDiscoveryResult, error)
+}
+
+// NewOauthDiscovery creates a new OauthDiscovery
+func NewOauthDiscovery(client HTTPClient) *OauthDiscovery {
+	return &OauthDiscovery{
+		c: client,
+	}
+}
+
+// OauthDiscoveryResult is the result of a OauthLocation discovery call
+// and contains all the parameters usable for a following oauth flow
+type OauthDiscoveryResult struct {
+	Issuer                 string   `json:"issuer"`
+	AuthorizationEndpoint  string   `json:"authorization_endpoint"`
+	TokenEndpoint          string   `json:"token_endpoint"`
+	UserinfoEndpoint       string   `json:"userinfo_endpoint"`
+	EndSessionEndpoint     string   `json:"end_session_endpoint"`
+	ResponseTypesSupported []string `json:"response_types_supported"`
+	GrantTypesSupported    []string `json:"grant_types_supported"`
+	JwksURI                string   `json:"jwks_uri"`
+	IntrospectionEndpoint  string   `json:"introspection_endpoint"`
+}
+
+// OauthDiscovery is an implementation of OauthLocationGetter which calls
+// a known URL to get the parameters
+type OauthDiscovery struct {
+	c HTTPClient
+}
+
+// Discover starts the OAuth discovery and eventually returns the results
+func (d OauthDiscovery) Discover(ctx context.Context, discoveryURL string) (*OauthDiscoveryResult, error) {
+	ctx, cancel := context.WithTimeout(ctx, 10*time.Second)
+	defer cancel()
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, discoveryURL, nil)
+	if err != nil {
+		return nil, err
+	}
+	resp, err := d.c.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf(http.StatusText(resp.StatusCode))
+	}
+
+	var result OauthDiscoveryResult
+	return &result, json.NewDecoder(resp.Body).Decode(&result)
+}
+
+// StaticOauthDiscovery has a static/hard-coded set of oauth parameters
+// and does not actually do a discovery call to get the parameters but just returns
+// the hard-coded values as OauthDiscoveryResult
+type StaticOauthDiscovery struct {
+	DiscoveryValues *OauthDiscoveryResult
+}
+
+// Discover tries to determine the parameters used for an oauth flow
+// and returns them as a OauthDiscoveryResult
+func (d StaticOauthDiscovery) Discover(ctx context.Context, discoveryURL string) (*OauthDiscoveryResult, error) {
+	return d.DiscoveryValues, nil
+}
+
+// OauthDiscoveryMock is an implementation of OauthLocationGetter usable
+// as a mock implementation in tests
+type OauthDiscoveryMock struct {
+	DiscoverFn func(context.Context, string) (*OauthDiscoveryResult, error)
+}
+
+// Discover calls the mocked function of the OauthDiscoveryMock
+func (o *OauthDiscoveryMock) Discover(ctx context.Context, discoveryURL string) (*OauthDiscoveryResult, error) {
+	if o != nil && o.DiscoverFn != nil {
+		return o.DiscoverFn(ctx, discoveryURL)
+	}
+	return &OauthDiscoveryResult{}, nil
+}
+
+// HTTPClient is an interface that models *http.Client.
+type HTTPClient interface {
+	Do(req *http.Request) (*http.Response, error)
+}

pkg/common/oauth2/discovery_test.go

@@ -0,0 +1,69 @@
+package oauthutils
+
+import (
+	"context"
+	"fmt"
+	"github.com/keptn/go-utils/pkg/common/testutils"
+	"github.com/stretchr/testify/assert"
+	"io"
+	"net/http"
+	"strings"
+	"testing"
+)
+
+func TestDiscovery(t *testing.T) {
+	response := `{"issuer":"https://issuer.com:443","authorization_endpoint":"https://endpoint.com:443/oauth2/authorize","token_endpoint":"https://tokenendpoint.com:443/sso/oauth2/token","userinfo_endpoint":"https://userinfo.com:443/sso/oauth2/userinfo","end_session_endpoint":"https://endsession.com:443/oauth2/end_session","response_types_supported":["code"],"grant_types_supported":["authorization_code","refresh_token","password","client_credentials","urn:ietf:params:oauth:grant-type:token-exchange"],"jwks_uri":"https://jwksuri.com:443/.well-known/jwks.json","introspection_endpoint":"https://introspection.com:443/sso/oauth2/tokeninfo","subject_types_supported":["public"],"id_token_signing_alg_values_supported":["ECDSA256"]}`
+	client := &testutils.HTTPClientMock{}
+	discovery := NewOauthDiscovery(client)
+	tt := []struct {
+		Body       string
+		StatusCode int
+		expResult  *OauthDiscoveryResult
+		expErr     error
+	}{
+		{
+			Body:       response,
+			StatusCode: 200,
+			expResult: &OauthDiscoveryResult{
+				Issuer:                 "https://issuer.com:443",
+				AuthorizationEndpoint:  "https://endpoint.com:443/oauth2/authorize",
+				TokenEndpoint:          "https://tokenendpoint.com:443/sso/oauth2/token",
+				UserinfoEndpoint:       "https://userinfo.com:443/sso/oauth2/userinfo",
+				EndSessionEndpoint:     "https://endsession.com:443/oauth2/end_session",
+				ResponseTypesSupported: []string{"code"},
+				GrantTypesSupported:    []string{"authorization_code", "refresh_token", "password", "client_credentials", "urn:ietf:params:oauth:grant-type:token-exchange"},
+				JwksURI:                "https://jwksuri.com:443/.well-known/jwks.json",
+				IntrospectionEndpoint:  "https://introspection.com:443/sso/oauth2/tokeninfo",
+			},
+			expErr: nil,
+		}, {
+			Body:       "",
+			StatusCode: http.StatusNotFound,
+			expResult:  nil,
+			expErr:     fmt.Errorf(http.StatusText(http.StatusNotFound)),
+		}, {
+			Body:       "",
+			StatusCode: http.StatusBadRequest,
+			expResult:  nil,
+			expErr:     fmt.Errorf(http.StatusText(http.StatusBadRequest)),
+		},
+	}
+
+	for _, test := range tt {
+		client.DoFunc = func(r *http.Request) (*http.Response, error) {
+			return &http.Response{
+				Body:       io.NopCloser(strings.NewReader(test.Body)),
+				StatusCode: test.StatusCode,
+			}, nil
+		}
+		r, err := discovery.Discover(context.Background(), "http://well-known-discovery-url.com")
+
+		assert.Equal(t, test.expErr, err)
+		assert.Equal(t, test.expResult, r)
+	}
+
+	_, err := discovery.Discover(context.TODO(), "http://well-known-discovery-url.com")
+	if err != nil {
+		return
+	}
+}