2 files changed, 207 insertions, 0 deletions
diff --git a/go/internal/gitlabnet/discover/client.go b/go/internal/gitlabnet/discover/client.go
new file mode 100644
index 0000000..8df78fb
--- /dev/null
+++ b/go/internal/gitlabnet/discover/client.go
@@ -0,0 +1,76 @@
+package discover
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+
+	"gitlab.com/gitlab-org/gitlab-shell/go/internal/config"
+	"gitlab.com/gitlab-org/gitlab-shell/go/internal/gitlabnet"
+)
+
+type Client struct {
+	config *config.Config
+	client gitlabnet.GitlabClient
+}
+
+type Response struct {
+	UserId   int64  `json:"id"`
+	Name     string `json:"name"`
+	Username string `json:"username"`
+}
+
+func NewClient(config *config.Config) (*Client, error) {
+	client, err := gitlabnet.GetClient(config)
+	if err != nil {
+		return nil, fmt.Errorf("Error creating http client: %v", err)
+	}
+
+	return &Client{config: config, client: client}, nil
+}
+
+func (c *Client) GetByKeyId(keyId string) (*Response, error) {
+	params := url.Values{}
+	params.Add("key_id", keyId)
+
+	return c.getResponse(params)
+}
+
+func (c *Client) GetByUsername(username string) (*Response, error) {
+	params := url.Values{}
+	params.Add("username", username)
+
+	return c.getResponse(params)
+}
+
+func (c *Client) parseResponse(resp *http.Response) (*Response, error) {
+	parsedResponse := &Response{}
+
+	if err := json.NewDecoder(resp.Body).Decode(parsedResponse); err != nil {
+		return nil, err
+	} else {
+		return parsedResponse, nil
+	}
+}
+
+func (c *Client) getResponse(params url.Values) (*Response, error) {
+	path := "/discover?" + params.Encode()
+	response, err := c.client.Get(path)
+
+	if err != nil {
+		return nil, err
+	}
+
+	defer response.Body.Close()
+	parsedResponse, err := c.parseResponse(response)
+	if err != nil {
+		return nil, fmt.Errorf("Parsing failed")
+	}
+
+	return parsedResponse, nil
+}
+
+func (r *Response) IsAnonymous() bool {
+	return r.UserId < 1
+}
diff --git a/go/internal/gitlabnet/discover/client_test.go b/go/internal/gitlabnet/discover/client_test.go
new file mode 100644
index 0000000..e88cedd
--- /dev/null
+++ b/go/internal/gitlabnet/discover/client_test.go
@@ -0,0 +1,131 @@
+package discover
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"testing"
+
+	"gitlab.com/gitlab-org/gitlab-shell/go/internal/config"
+	"gitlab.com/gitlab-org/gitlab-shell/go/internal/gitlabnet"
+	"gitlab.com/gitlab-org/gitlab-shell/go/internal/gitlabnet/testserver"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+var (
+	testConfig *config.Config
+	requests   []testserver.TestRequestHandler
+)
+
+func init() {
+	testConfig = &config.Config{GitlabUrl: "http+unix://" + testserver.TestSocket}
+	requests = []testserver.TestRequestHandler{
+		{
+			Path: "/api/v4/internal/discover",
+			Handler: func(w http.ResponseWriter, r *http.Request) {
+				if r.URL.Query().Get("key_id") == "1" {
+					body := &Response{
+						UserId:   2,
+						Username: "alex-doe",
+						Name:     "Alex Doe",
+					}
+					json.NewEncoder(w).Encode(body)
+				} else if r.URL.Query().Get("username") == "jane-doe" {
+					body := &Response{
+						UserId:   1,
+						Username: "jane-doe",
+						Name:     "Jane Doe",
+					}
+					json.NewEncoder(w).Encode(body)
+				} else if r.URL.Query().Get("username") == "broken_message" {
+					w.WriteHeader(http.StatusForbidden)
+					body := &gitlabnet.ErrorResponse{
+						Message: "Not allowed!",
+					}
+					json.NewEncoder(w).Encode(body)
+				} else if r.URL.Query().Get("username") == "broken_json" {
+					w.Write([]byte("{ \"message\": \"broken json!\""))
+				} else if r.URL.Query().Get("username") == "broken_empty" {
+					w.WriteHeader(http.StatusForbidden)
+				} else {
+					fmt.Fprint(w, "null")
+				}
+			},
+		},
+	}
+}
+
+func TestGetByKeyId(t *testing.T) {
+	client, cleanup := setup(t)
+	defer cleanup()
+
+	result, err := client.GetByKeyId("1")
+	assert.NoError(t, err)
+	assert.Equal(t, &Response{UserId: 2, Username: "alex-doe", Name: "Alex Doe"}, result)
+}
+
+func TestGetByUsername(t *testing.T) {
+	client, cleanup := setup(t)
+	defer cleanup()
+
+	result, err := client.GetByUsername("jane-doe")
+	assert.NoError(t, err)
+	assert.Equal(t, &Response{UserId: 1, Username: "jane-doe", Name: "Jane Doe"}, result)
+}
+
+func TestMissingUser(t *testing.T) {
+	client, cleanup := setup(t)
+	defer cleanup()
+
+	result, err := client.GetByUsername("missing")
+	assert.NoError(t, err)
+	assert.True(t, result.IsAnonymous())
+}
+
+func TestErrorResponses(t *testing.T) {
+	client, cleanup := setup(t)
+	defer cleanup()
+
+	testCases := []struct {
+		desc          string
+		fakeUsername  string
+		expectedError string
+	}{
+		{
+			desc:          "A response with an error message",
+			fakeUsername:  "broken_message",
+			expectedError: "Not allowed!",
+		},
+		{
+			desc:          "A response with bad JSON",
+			fakeUsername:  "broken_json",
+			expectedError: "Parsing failed",
+		},
+		{
+			desc:          "An error response without message",
+			fakeUsername:  "broken_empty",
+			expectedError: "Internal API error (403)",
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.desc, func(t *testing.T) {
+			resp, err := client.GetByUsername(tc.fakeUsername)
+
+			assert.EqualError(t, err, tc.expectedError)
+			assert.Nil(t, resp)
+		})
+	}
+}
+
+func setup(t *testing.T) (*Client, func()) {
+	cleanup, err := testserver.StartSocketHttpServer(requests)
+	require.NoError(t, err)
+
+	client, err := NewClient(testConfig)
+	require.NoError(t, err)
+
+	return client, cleanup
+}