Add a gh variable get FOO command (#9106)

Closes #9103.

---------

Co-authored-by: William Martin <williammartin@github.com>

pkg/cmd/variable/get/get.go

@@ -0,0 +1,132 @@
+package get
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+
+	"github.com/MakeNowJust/heredoc"
+	"github.com/cli/cli/v2/api"
+	"github.com/cli/cli/v2/internal/gh"
+	"github.com/cli/cli/v2/internal/ghrepo"
+	"github.com/cli/cli/v2/pkg/cmd/variable/shared"
+	"github.com/cli/cli/v2/pkg/cmdutil"
+	"github.com/cli/cli/v2/pkg/iostreams"
+	"github.com/spf13/cobra"
+)
+
+type GetOptions struct {
+	HttpClient func() (*http.Client, error)
+	IO         *iostreams.IOStreams
+	Config     func() (gh.Config, error)
+	BaseRepo   func() (ghrepo.Interface, error)
+
+	VariableName string
+	OrgName      string
+	EnvName      string
+}
+
+type getVariableResponse struct {
+	Value string `json:"value"`
+	// Other available but unused fields
+	// Name             string            `json:"name"`
+	// UpdatedAt        time.Time         `json:"updated_at"`
+	// Visibility       shared.Visibility `json:"visibility"`
+	// SelectedReposURL string            `json:"selected_repositories_url"`
+	// NumSelectedRepos int               `json:"num_selected_repos"`
+}
+
+func NewCmdGet(f *cmdutil.Factory, runF func(*GetOptions) error) *cobra.Command {
+	opts := &GetOptions{
+		IO:         f.IOStreams,
+		Config:     f.Config,
+		HttpClient: f.HttpClient,
+	}
+
+	cmd := &cobra.Command{
+		Use:   "get <variable-name>",
+		Short: "Get variables",
+		Long: heredoc.Doc(`
+			Get a variable on one of the following levels:
+			- repository (default): available to GitHub Actions runs or Dependabot in a repository
+			- environment: available to GitHub Actions runs for a deployment environment in a repository
+			- organization: available to GitHub Actions runs or Dependabot within an organization
+		`),
+		Args: cobra.ExactArgs(1),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			// support `-R, --repo` override
+			opts.BaseRepo = f.BaseRepo
+
+			if err := cmdutil.MutuallyExclusive("specify only one of `--org` or `--env`", opts.OrgName != "", opts.EnvName != ""); err != nil {
+				return err
+			}
+
+			opts.VariableName = args[0]
+
+			if runF != nil {
+				return runF(opts)
+			}
+
+			return getRun(opts)
+		},
+	}
+	cmd.Flags().StringVarP(&opts.OrgName, "org", "o", "", "Get a variable for an organization")
+	cmd.Flags().StringVarP(&opts.EnvName, "env", "e", "", "Get a variable for an environment")
+
+	return cmd
+}
+
+func getRun(opts *GetOptions) error {
+	c, err := opts.HttpClient()
+	if err != nil {
+		return fmt.Errorf("could not create http client: %w", err)
+	}
+	client := api.NewClientFromHTTP(c)
+
+	orgName := opts.OrgName
+	envName := opts.EnvName
+
+	variableEntity, err := shared.GetVariableEntity(orgName, envName)
+	if err != nil {
+		return err
+	}
+
+	var baseRepo ghrepo.Interface
+	if variableEntity == shared.Repository || variableEntity == shared.Environment {
+		baseRepo, err = opts.BaseRepo()
+		if err != nil {
+			return err
+		}
+	}
+
+	var path string
+	switch variableEntity {
+	case shared.Organization:
+		path = fmt.Sprintf("orgs/%s/actions/variables/%s", orgName, opts.VariableName)
+	case shared.Environment:
+		path = fmt.Sprintf("repos/%s/environments/%s/variables/%s", ghrepo.FullName(baseRepo), envName, opts.VariableName)
+	case shared.Repository:
+		path = fmt.Sprintf("repos/%s/actions/variables/%s", ghrepo.FullName(baseRepo), opts.VariableName)
+	}
+
+	cfg, err := opts.Config()
+	if err != nil {
+		return err
+	}
+
+	host, _ := cfg.Authentication().DefaultHost()
+
+	var response getVariableResponse
+	if err = client.REST(host, "GET", path, nil, &response); err != nil {
+		var httpErr api.HTTPError
+		if errors.As(err, &httpErr) && httpErr.StatusCode == http.StatusNotFound {
+			return fmt.Errorf("variable %s was not found", opts.VariableName)
+		}
+
+		return fmt.Errorf("failed to get variable %s: %w", opts.VariableName, err)
+	}
+
+	fmt.Fprintf(opts.IO.Out, "%s\n", response.Value)
+
+	return nil
+}

pkg/cmd/variable/get/get_test.go

@@ -0,0 +1,202 @@
+package get
+
+import (
+	"bytes"
+	"fmt"
+	"net/http"
+	"testing"
+
+	"github.com/cli/cli/v2/internal/config"
+	"github.com/cli/cli/v2/internal/gh"
+	"github.com/cli/cli/v2/internal/ghrepo"
+	"github.com/cli/cli/v2/pkg/cmdutil"
+	"github.com/cli/cli/v2/pkg/httpmock"
+	"github.com/cli/cli/v2/pkg/iostreams"
+	"github.com/google/shlex"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestNewCmdGet(t *testing.T) {
+	tests := []struct {
+		name    string
+		cli     string
+		wants   GetOptions
+		wantErr error
+	}{
+		{
+			name: "repo",
+			cli:  "FOO",
+			wants: GetOptions{
+				OrgName:      "",
+				VariableName: "FOO",
+			},
+		},
+		{
+			name: "org",
+			cli:  "-o TestOrg BAR",
+			wants: GetOptions{
+				OrgName:      "TestOrg",
+				VariableName: "BAR",
+			},
+		},
+		{
+			name: "env",
+			cli:  "-e Development BAZ",
+			wants: GetOptions{
+				EnvName:      "Development",
+				VariableName: "BAZ",
+			},
+		},
+		{
+			name:    "org and env",
+			cli:     "-o TestOrg -e Development QUX",
+			wantErr: cmdutil.FlagErrorf("%s", "specify only one of `--org` or `--env`"),
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ios, _, _, _ := iostreams.Test()
+			f := &cmdutil.Factory{
+				IOStreams: ios,
+			}
+
+			argv, err := shlex.Split(tt.cli)
+			assert.NoError(t, err)
+
+			var gotOpts *GetOptions
+			cmd := NewCmdGet(f, func(opts *GetOptions) error {
+				gotOpts = opts
+				return nil
+			})
+			cmd.SetArgs(argv)
+			cmd.SetIn(&bytes.Buffer{})
+			cmd.SetOut(&bytes.Buffer{})
+			cmd.SetErr(&bytes.Buffer{})
+
+			_, err = cmd.ExecuteC()
+			if tt.wantErr != nil {
+				require.Equal(t, err, tt.wantErr)
+				return
+			}
+			require.NoError(t, err)
+
+			require.Equal(t, tt.wants.OrgName, gotOpts.OrgName)
+			require.Equal(t, tt.wants.EnvName, gotOpts.EnvName)
+			require.Equal(t, tt.wants.VariableName, gotOpts.VariableName)
+		})
+	}
+}
+
+func Test_getRun(t *testing.T) {
+	tests := []struct {
+		name      string
+		opts      *GetOptions
+		httpStubs func(*httpmock.Registry)
+		wantOut   string
+		wantErr   error
+	}{
+		{
+			name: "getting repo variable",
+			opts: &GetOptions{
+				VariableName: "VARIABLE_ONE",
+			},
+			httpStubs: func(reg *httpmock.Registry) {
+				reg.Register(httpmock.REST("GET", "repos/owner/repo/actions/variables/VARIABLE_ONE"),
+					httpmock.JSONResponse(getVariableResponse{
+						Value: "repo_var",
+					}))
+			},
+			wantOut: "repo_var\n",
+		},
+		{
+			name: "getting org variable",
+			opts: &GetOptions{
+				OrgName:      "TestOrg",
+				VariableName: "VARIABLE_ONE",
+			},
+			httpStubs: func(reg *httpmock.Registry) {
+				reg.Register(httpmock.REST("GET", "orgs/TestOrg/actions/variables/VARIABLE_ONE"),
+					httpmock.JSONResponse(getVariableResponse{
+						Value: "org_var",
+					}))
+			},
+			wantOut: "org_var\n",
+		},
+		{
+			name: "getting env variable",
+			opts: &GetOptions{
+				EnvName:      "Development",
+				VariableName: "VARIABLE_ONE",
+			},
+			httpStubs: func(reg *httpmock.Registry) {
+				reg.Register(httpmock.REST("GET", "repos/owner/repo/environments/Development/variables/VARIABLE_ONE"),
+					httpmock.JSONResponse(getVariableResponse{
+						Value: "env_var",
+					}))
+			},
+			wantOut: "env_var\n",
+		},
+		{
+			name: "when the variable is not found, an error is returned",
+			opts: &GetOptions{
+				VariableName: "VARIABLE_ONE",
+			},
+			httpStubs: func(reg *httpmock.Registry) {
+				reg.Register(httpmock.REST("GET", "repos/owner/repo/actions/variables/VARIABLE_ONE"),
+					httpmock.StatusStringResponse(404, "not found"),
+				)
+			},
+			wantErr: fmt.Errorf("variable VARIABLE_ONE was not found"),
+		},
+		{
+			name: "when getting any variable from API fails, the error is bubbled with context",
+			opts: &GetOptions{
+				VariableName: "VARIABLE_ONE",
+			},
+			httpStubs: func(reg *httpmock.Registry) {
+				reg.Register(httpmock.REST("GET", "repos/owner/repo/actions/variables/VARIABLE_ONE"),
+					httpmock.StatusStringResponse(400, "not found"),
+				)
+			},
+			wantErr: fmt.Errorf("failed to get variable VARIABLE_ONE: HTTP 400 (https://api.github.com/repos/owner/repo/actions/variables/VARIABLE_ONE)"),
+		},
+	}
+
+	for _, tt := range tests {
+		var runTest = func(tty bool) func(t *testing.T) {
+			return func(t *testing.T) {
+				reg := &httpmock.Registry{}
+				tt.httpStubs(reg)
+				defer reg.Verify(t)
+
+				ios, _, stdout, _ := iostreams.Test()
+				ios.SetStdoutTTY(tty)
+
+				tt.opts.IO = ios
+				tt.opts.BaseRepo = func() (ghrepo.Interface, error) {
+					return ghrepo.FromFullName("owner/repo")
+				}
+				tt.opts.HttpClient = func() (*http.Client, error) {
+					return &http.Client{Transport: reg}, nil
+				}
+				tt.opts.Config = func() (gh.Config, error) {
+					return config.NewBlankConfig(), nil
+				}
+
+				err := getRun(tt.opts)
+				if err != nil {
+					require.EqualError(t, tt.wantErr, err.Error())
+					return
+				}
+
+				require.NoError(t, err)
+				require.Equal(t, tt.wantOut, stdout.String())
+			}
+		}
+
+		t.Run(tt.name+" tty", runTest(true))
+		t.Run(tt.name+" no-tty", runTest(false))
+	}
+}

pkg/cmd/variable/variable.go

@@ -3,6 +3,7 @@ package variable
 import (
 	"github.com/MakeNowJust/heredoc"
 	cmdDelete "github.com/cli/cli/v2/pkg/cmd/variable/delete"
+	cmdGet "github.com/cli/cli/v2/pkg/cmd/variable/get"
 	cmdList "github.com/cli/cli/v2/pkg/cmd/variable/list"
 	cmdSet "github.com/cli/cli/v2/pkg/cmd/variable/set"
 	"github.com/cli/cli/v2/pkg/cmdutil"
@@ -21,6 +22,7 @@ func NewCmdVariable(f *cmdutil.Factory) *cobra.Command {
 
 	cmdutil.EnableRepoOverride(cmd, f)
 
+	cmd.AddCommand(cmdGet.NewCmdGet(f, nil))
 	cmd.AddCommand(cmdSet.NewCmdSet(f, nil))
 	cmd.AddCommand(cmdList.NewCmdList(f, nil))
 	cmd.AddCommand(cmdDelete.NewCmdDelete(f, nil))