Merge 5b21a0e271 into 15157c1c40

* chore: add network integration test suite scaffolding

* dean comments

cli/cliui/parameter.go

@@ -10,7 +10,7 @@ import (
 	"github.com/coder/serpent"
 )
 
-func RichParameter(inv *serpent.Invocation, templateVersionParameter codersdk.TemplateVersionParameter) (string, error) {
+func RichParameter(inv *serpent.Invocation, templateVersionParameter codersdk.TemplateVersionParameter, defaults map[string]string) (string, error) {
 	label := templateVersionParameter.Name
 	if templateVersionParameter.DisplayName != "" {
 		label = templateVersionParameter.DisplayName
@@ -26,6 +26,11 @@ func RichParameter(inv *serpent.Invocation, templateVersionParameter codersdk.Te
 		_, _ = fmt.Fprintln(inv.Stdout, "  "+strings.TrimSpace(strings.Join(strings.Split(templateVersionParameter.DescriptionPlaintext, "\n"), "\n  "))+"\n")
 	}
 
+	defaultValue := templateVersionParameter.DefaultValue
+	if v, ok := defaults[templateVersionParameter.Name]; ok {
+		defaultValue = v
+	}
+
 	var err error
 	var value string
 	if templateVersionParameter.Type == "list(string)" {
@@ -58,7 +63,7 @@ func RichParameter(inv *serpent.Invocation, templateVersionParameter codersdk.Te
 		var richParameterOption *codersdk.TemplateVersionParameterOption
 		richParameterOption, err = RichSelect(inv, RichSelectOptions{
 			Options:    templateVersionParameter.Options,
-			Default:    templateVersionParameter.DefaultValue,
+			Default:    defaultValue,
 			HideSearch: true,
 		})
 		if err == nil {
@@ -69,7 +74,7 @@ func RichParameter(inv *serpent.Invocation, templateVersionParameter codersdk.Te
 	} else {
 		text := "Enter a value"
 		if !templateVersionParameter.Required {
-			text += fmt.Sprintf(" (default: %q)", templateVersionParameter.DefaultValue)
+			text += fmt.Sprintf(" (default: %q)", defaultValue)
 		}
 		text += ":"
 
@@ -87,7 +92,7 @@ func RichParameter(inv *serpent.Invocation, templateVersionParameter codersdk.Te
 
 	// If they didn't specify anything, use the default value if set.
 	if len(templateVersionParameter.Options) == 0 && value == "" {
-		value = templateVersionParameter.DefaultValue
+		value = defaultValue
 	}
 
 	return value, nil

cli/create.go

@@ -165,6 +165,11 @@ func (r *RootCmd) create() *serpent.Command {
 				return xerrors.Errorf("can't parse given parameter values: %w", err)
 			}
 
+			cliBuildParameterDefaults, err := asWorkspaceBuildParameters(parameterFlags.richParameterDefaults)
+			if err != nil {
+				return xerrors.Errorf("can't parse given parameter defaults: %w", err)
+			}
+
 			var sourceWorkspaceParameters []codersdk.WorkspaceBuildParameter
 			if copyParametersFrom != "" {
 				sourceWorkspaceParameters, err = client.WorkspaceBuildParameters(inv.Context(), sourceWorkspace.LatestBuild.ID)
@@ -178,8 +183,9 @@ func (r *RootCmd) create() *serpent.Command {
 				TemplateVersionID: templateVersionID,
 				NewWorkspaceName:  workspaceName,
 
-				RichParameterFile: parameterFlags.richParameterFile,
-				RichParameters:    cliBuildParameters,
+				RichParameterFile:     parameterFlags.richParameterFile,
+				RichParameters:        cliBuildParameters,
+				RichParameterDefaults: cliBuildParameterDefaults,
 
 				SourceWorkspaceParameters: sourceWorkspaceParameters,
 			})
@@ -262,6 +268,7 @@ func (r *RootCmd) create() *serpent.Command {
 		cliui.SkipPromptOption(),
 	)
 	cmd.Options = append(cmd.Options, parameterFlags.cliParameters()...)
+	cmd.Options = append(cmd.Options, parameterFlags.cliParameterDefaults()...)
 	return cmd
 }
 
@@ -276,9 +283,10 @@ type prepWorkspaceBuildArgs struct {
 	PromptBuildOptions bool
 	BuildOptions       []codersdk.WorkspaceBuildParameter
 
-	PromptRichParameters bool
-	RichParameters       []codersdk.WorkspaceBuildParameter
-	RichParameterFile    string
+	PromptRichParameters  bool
+	RichParameters        []codersdk.WorkspaceBuildParameter
+	RichParameterFile     string
+	RichParameterDefaults []codersdk.WorkspaceBuildParameter
 }
 
 // prepWorkspaceBuild will ensure a workspace build will succeed on the latest template version.
@@ -311,7 +319,8 @@ func prepWorkspaceBuild(inv *serpent.Invocation, client *codersdk.Client, args p
 		WithBuildOptions(args.BuildOptions).
 		WithPromptRichParameters(args.PromptRichParameters).
 		WithRichParameters(args.RichParameters).
-		WithRichParametersFile(parameterFile)
+		WithRichParametersFile(parameterFile).
+		WithRichParametersDefaults(args.RichParameterDefaults)
 	buildParameters, err := resolver.Resolve(inv, args.Action, templateVersionParameters)
 	if err != nil {
 		return nil, err

cli/create_test.go

@@ -315,6 +315,68 @@ func TestCreateWithRichParameters(t *testing.T) {
 		<-doneChan
 	})
 
+	t.Run("ParametersDefaults", func(t *testing.T) {
+		t.Parallel()
+
+		client := coderdtest.New(t, &coderdtest.Options{IncludeProvisionerDaemon: true})
+		owner := coderdtest.CreateFirstUser(t, client)
+		member, _ := coderdtest.CreateAnotherUser(t, client, owner.OrganizationID)
+		version := coderdtest.CreateTemplateVersion(t, client, owner.OrganizationID, echoResponses)
+		coderdtest.AwaitTemplateVersionJobCompleted(t, client, version.ID)
+
+		template := coderdtest.CreateTemplate(t, client, owner.OrganizationID, version.ID)
+
+		inv, root := clitest.New(t, "create", "my-workspace", "--template", template.Name,
+			"--parameter-default", fmt.Sprintf("%s=%s", firstParameterName, firstParameterValue),
+			"--parameter-default", fmt.Sprintf("%s=%s", secondParameterName, secondParameterValue),
+			"--parameter-default", fmt.Sprintf("%s=%s", immutableParameterName, immutableParameterValue))
+		clitest.SetupConfig(t, member, root)
+		doneChan := make(chan struct{})
+		pty := ptytest.New(t).Attach(inv)
+		go func() {
+			defer close(doneChan)
+			err := inv.Run()
+			assert.NoError(t, err)
+		}()
+
+		matches := []string{
+			firstParameterDescription, firstParameterValue,
+			secondParameterDescription, secondParameterValue,
+			immutableParameterDescription, immutableParameterValue,
+		}
+		for i := 0; i < len(matches); i += 2 {
+			match := matches[i]
+			defaultValue := matches[i+1]
+
+			pty.ExpectMatch(match)
+			pty.ExpectMatch(`Enter a value (default: "` + defaultValue + `")`)
+			pty.WriteLine("")
+		}
+		pty.ExpectMatch("Confirm create?")
+		pty.WriteLine("yes")
+		<-doneChan
+
+		// Verify that the expected default values were used.
+		ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitShort)
+		defer cancel()
+
+		workspaces, err := client.Workspaces(ctx, codersdk.WorkspaceFilter{
+			Name: "my-workspace",
+		})
+		require.NoError(t, err, "can't list available workspaces")
+		require.Len(t, workspaces.Workspaces, 1)
+
+		workspaceLatestBuild := workspaces.Workspaces[0].LatestBuild
+		require.Equal(t, version.ID, workspaceLatestBuild.TemplateVersionID)
+
+		buildParameters, err := client.WorkspaceBuildParameters(ctx, workspaceLatestBuild.ID)
+		require.NoError(t, err)
+		require.Len(t, buildParameters, 3)
+		require.Contains(t, buildParameters, codersdk.WorkspaceBuildParameter{Name: firstParameterName, Value: firstParameterValue})
+		require.Contains(t, buildParameters, codersdk.WorkspaceBuildParameter{Name: secondParameterName, Value: secondParameterValue})
+		require.Contains(t, buildParameters, codersdk.WorkspaceBuildParameter{Name: immutableParameterName, Value: immutableParameterValue})
+	})
+
 	t.Run("RichParametersFile", func(t *testing.T) {
 		t.Parallel()
 

cli/parameter.go

@@ -18,14 +18,16 @@ type workspaceParameterFlags struct {
 	promptBuildOptions bool
 	buildOptions       []string
 
-	richParameterFile string
-	richParameters    []string
+	richParameterFile     string
+	richParameters        []string
+	richParameterDefaults []string
 
 	promptRichParameters bool
 }
 
 func (wpf *workspaceParameterFlags) allOptions() []serpent.Option {
 	options := append(wpf.cliBuildOptions(), wpf.cliParameters()...)
+	options = append(options, wpf.cliParameterDefaults()...)
 	return append(options, wpf.alwaysPrompt())
 }
 
@@ -62,6 +64,17 @@ func (wpf *workspaceParameterFlags) cliParameters() []serpent.Option {
 	}
 }
 
+func (wpf *workspaceParameterFlags) cliParameterDefaults() []serpent.Option {
+	return serpent.OptionSet{
+		serpent.Option{
+			Flag:        "parameter-default",
+			Env:         "CODER_RICH_PARAMETER_DEFAULT",
+			Description: `Rich parameter default values in the format "name=value".`,
+			Value:       serpent.StringArrayOf(&wpf.richParameterDefaults),
+		},
+	}
+}
+
 func (wpf *workspaceParameterFlags) alwaysPrompt() serpent.Option {
 	return serpent.Option{
 		Flag:        "always-prompt",

cli/parameterresolver.go

@@ -26,9 +26,10 @@ type ParameterResolver struct {
 	lastBuildParameters       []codersdk.WorkspaceBuildParameter
 	sourceWorkspaceParameters []codersdk.WorkspaceBuildParameter
 
-	richParameters     []codersdk.WorkspaceBuildParameter
-	richParametersFile map[string]string
-	buildOptions       []codersdk.WorkspaceBuildParameter
+	richParameters         []codersdk.WorkspaceBuildParameter
+	richParametersDefaults map[string]string
+	richParametersFile     map[string]string
+	buildOptions           []codersdk.WorkspaceBuildParameter
 
 	promptRichParameters bool
 	promptBuildOptions   bool
@@ -59,6 +60,16 @@ func (pr *ParameterResolver) WithRichParametersFile(fileMap map[string]string) *
 	return pr
 }
 
+func (pr *ParameterResolver) WithRichParametersDefaults(params []codersdk.WorkspaceBuildParameter) *ParameterResolver {
+	if pr.richParametersDefaults == nil {
+		pr.richParametersDefaults = make(map[string]string)
+	}
+	for _, p := range params {
+		pr.richParametersDefaults[p.Name] = p.Value
+	}
+	return pr
+}
+
 func (pr *ParameterResolver) WithPromptRichParameters(promptRichParameters bool) *ParameterResolver {
 	pr.promptRichParameters = promptRichParameters
 	return pr
@@ -227,7 +238,7 @@ func (pr *ParameterResolver) resolveWithInput(resolved []codersdk.WorkspaceBuild
 			(action == WorkspaceUpdate && tvp.Mutable && tvp.Required) ||
 			(action == WorkspaceUpdate && !tvp.Mutable && firstTimeUse) ||
 			(tvp.Mutable && !tvp.Ephemeral && pr.promptRichParameters) {
-			parameterValue, err := cliui.RichParameter(inv, tvp)
+			parameterValue, err := cliui.RichParameter(inv, tvp, pr.richParametersDefaults)
 			if err != nil {
 				return nil, err
 			}

cli/start.go

@@ -99,7 +99,12 @@ func buildWorkspaceStartRequest(inv *serpent.Invocation, client *codersdk.Client
 
 	cliRichParameters, err := asWorkspaceBuildParameters(parameterFlags.richParameters)
 	if err != nil {
-		return codersdk.CreateWorkspaceBuildRequest{}, xerrors.Errorf("unable to parse build options: %w", err)
+		return codersdk.CreateWorkspaceBuildRequest{}, xerrors.Errorf("unable to parse rich parameters: %w", err)
+	}
+
+	cliRichParameterDefaults, err := asWorkspaceBuildParameters(parameterFlags.richParameterDefaults)
+	if err != nil {
+		return codersdk.CreateWorkspaceBuildRequest{}, xerrors.Errorf("unable to parse rich parameter defaults: %w", err)
 	}
 
 	buildParameters, err := prepWorkspaceBuild(inv, client, prepWorkspaceBuildArgs{
@@ -108,11 +113,12 @@ func buildWorkspaceStartRequest(inv *serpent.Invocation, client *codersdk.Client
 		NewWorkspaceName:    workspace.Name,
 		LastBuildParameters: lastBuildParameters,
 
-		PromptBuildOptions:   parameterFlags.promptBuildOptions,
-		BuildOptions:         buildOptions,
-		PromptRichParameters: parameterFlags.promptRichParameters,
-		RichParameters:       cliRichParameters,
-		RichParameterFile:    parameterFlags.richParameterFile,
+		PromptBuildOptions:    parameterFlags.promptBuildOptions,
+		BuildOptions:          buildOptions,
+		PromptRichParameters:  parameterFlags.promptRichParameters,
+		RichParameters:        cliRichParameters,
+		RichParameterFile:     parameterFlags.richParameterFile,
+		RichParameterDefaults: cliRichParameterDefaults,
 	})
 	if err != nil {
 		return codersdk.CreateWorkspaceBuildRequest{}, err

cli/testdata/coder_create_--help.golden

@@ -20,6 +20,9 @@ OPTIONS:
       --parameter string-array, $CODER_RICH_PARAMETER
           Rich parameter value in the format "name=value".
 
+      --parameter-default string-array, $CODER_RICH_PARAMETER_DEFAULT
+          Rich parameter default values in the format "name=value".
+
       --rich-parameter-file string, $CODER_RICH_PARAMETER_FILE
           Specify a file path with values for rich parameters defined in the
           template.

cli/testdata/coder_restart_--help.golden

@@ -19,6 +19,9 @@ OPTIONS:
       --parameter string-array, $CODER_RICH_PARAMETER
           Rich parameter value in the format "name=value".
 
+      --parameter-default string-array, $CODER_RICH_PARAMETER_DEFAULT
+          Rich parameter default values in the format "name=value".
+
       --rich-parameter-file string, $CODER_RICH_PARAMETER_FILE
           Specify a file path with values for rich parameters defined in the
           template.

cli/testdata/coder_start_--help.golden

@@ -19,6 +19,9 @@ OPTIONS:
       --parameter string-array, $CODER_RICH_PARAMETER
           Rich parameter value in the format "name=value".
 
+      --parameter-default string-array, $CODER_RICH_PARAMETER_DEFAULT
+          Rich parameter default values in the format "name=value".
+
       --rich-parameter-file string, $CODER_RICH_PARAMETER_FILE
           Specify a file path with values for rich parameters defined in the
           template.

cli/testdata/coder_update_--help.golden

@@ -21,6 +21,9 @@ OPTIONS:
       --parameter string-array, $CODER_RICH_PARAMETER
           Rich parameter value in the format "name=value".
 
+      --parameter-default string-array, $CODER_RICH_PARAMETER_DEFAULT
+          Rich parameter default values in the format "name=value".
+
       --rich-parameter-file string, $CODER_RICH_PARAMETER_FILE
           Specify a file path with values for rich parameters defined in the
           template.

docs/cli/create.md

@@ -91,3 +91,12 @@ Rich parameter value in the format "name=value".
 | Environment | <code>$CODER_RICH_PARAMETER_FILE</code> |
 
 Specify a file path with values for rich parameters defined in the template.
+
+### --parameter-default
+
+|             |                                            |
+| ----------- | ------------------------------------------ |
+| Type        | <code>string-array</code>                  |
+| Environment | <code>$CODER_RICH_PARAMETER_DEFAULT</code> |
+
+Rich parameter default values in the format "name=value".

docs/cli/restart.md

@@ -55,6 +55,15 @@ Rich parameter value in the format "name=value".
 
 Specify a file path with values for rich parameters defined in the template.
 
+### --parameter-default
+
+|             |                                            |
+| ----------- | ------------------------------------------ |
+| Type        | <code>string-array</code>                  |
+| Environment | <code>$CODER_RICH_PARAMETER_DEFAULT</code> |
+
+Rich parameter default values in the format "name=value".
+
 ### --always-prompt
 
 |      |                   |

docs/cli/start.md

@@ -55,6 +55,15 @@ Rich parameter value in the format "name=value".
 
 Specify a file path with values for rich parameters defined in the template.
 
+### --parameter-default
+
+|             |                                            |
+| ----------- | ------------------------------------------ |
+| Type        | <code>string-array</code>                  |
+| Environment | <code>$CODER_RICH_PARAMETER_DEFAULT</code> |
+
+Rich parameter default values in the format "name=value".
+
 ### --always-prompt
 
 |      |                   |

docs/cli/update.md

@@ -53,6 +53,15 @@ Rich parameter value in the format "name=value".
 
 Specify a file path with values for rich parameters defined in the template.
 
+### --parameter-default
+
+|             |                                            |
+| ----------- | ------------------------------------------ |
+| Type        | <code>string-array</code>                  |
+| Environment | <code>$CODER_RICH_PARAMETER_DEFAULT</code> |
+
+Rich parameter default values in the format "name=value".
+
 ### --always-prompt
 
 |      |                   |

tailnet/test/integration/integration.go

@@ -0,0 +1,128 @@
+package integration
+
+import (
+	"context"
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"net/netip"
+	"strings"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/require"
+	"golang.org/x/xerrors"
+	"nhooyr.io/websocket"
+	"tailscale.com/tailcfg"
+
+	"cdr.dev/slog"
+	"github.com/coder/coder/v2/coderd/httpapi"
+	"github.com/coder/coder/v2/codersdk"
+	"github.com/coder/coder/v2/tailnet"
+	"github.com/coder/coder/v2/testutil"
+)
+
+func NetworkSetupDefault(*testing.T) {}
+
+func DERPMapTailscale(ctx context.Context, t *testing.T) *tailcfg.DERPMap {
+	ctx, cancel := context.WithTimeout(ctx, testutil.WaitShort)
+	defer cancel()
+
+	req, err := http.NewRequestWithContext(ctx, "GET", "https://controlplane.tailscale.com/derpmap/default", nil)
+	require.NoError(t, err)
+
+	res, err := http.DefaultClient.Do(req)
+	require.NoError(t, err)
+	defer res.Body.Close()
+
+	dm := &tailcfg.DERPMap{}
+	dec := json.NewDecoder(res.Body)
+	err = dec.Decode(dm)
+	require.NoError(t, err)
+
+	return dm
+}
+
+func CoordinatorInMemory(t *testing.T, logger slog.Logger, dm *tailcfg.DERPMap) (coord tailnet.Coordinator, url string) {
+	coord = tailnet.NewCoordinator(logger)
+	var coordPtr atomic.Pointer[tailnet.Coordinator]
+	coordPtr.Store(&coord)
+	t.Cleanup(func() { _ = coord.Close() })
+
+	csvc, err := tailnet.NewClientService(logger, &coordPtr, 10*time.Minute, func() *tailcfg.DERPMap {
+		return dm
+	})
+	require.NoError(t, err)
+
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		idStr := strings.TrimPrefix(r.URL.Path, "/")
+		id, err := uuid.Parse(idStr)
+		if err != nil {
+			httpapi.Write(r.Context(), w, http.StatusBadRequest, codersdk.Response{
+				Message: "Bad agent id.",
+				Detail:  err.Error(),
+			})
+			return
+		}
+
+		conn, err := websocket.Accept(w, r, nil)
+		if err != nil {
+			httpapi.Write(r.Context(), w, http.StatusBadRequest, codersdk.Response{
+				Message: "Failed to accept websocket.",
+				Detail:  err.Error(),
+			})
+			return
+		}
+
+		ctx, wsNetConn := codersdk.WebsocketNetConn(r.Context(), conn, websocket.MessageBinary)
+		defer wsNetConn.Close()
+
+		err = csvc.ServeConnV2(ctx, wsNetConn, tailnet.StreamID{
+			Name: "client-" + id.String(),
+			ID:   id,
+			Auth: tailnet.SingleTailnetCoordinateeAuth{},
+		})
+		if err != nil && !xerrors.Is(err, io.EOF) && !xerrors.Is(err, context.Canceled) {
+			_ = conn.Close(websocket.StatusInternalError, err.Error())
+			return
+		}
+	}))
+	t.Cleanup(srv.Close)
+
+	return coord, srv.URL
+}
+
+func TailnetSetupDRPC(ctx context.Context, t *testing.T, logger slog.Logger,
+	id, agentID uuid.UUID,
+	coordinateURL string,
+	dm *tailcfg.DERPMap,
+) *tailnet.Conn {
+	ip := tailnet.IPFromUUID(id)
+	conn, err := tailnet.NewConn(&tailnet.Options{
+		Addresses: []netip.Prefix{netip.PrefixFrom(ip, 128)},
+		DERPMap:   dm,
+		Logger:    logger,
+	})
+	require.NoError(t, err)
+	t.Cleanup(func() { _ = conn.Close() })
+
+	//nolint:bodyclose
+	ws, _, err := websocket.Dial(ctx, coordinateURL+"/"+id.String(), nil)
+	require.NoError(t, err)
+
+	client, err := tailnet.NewDRPCClient(
+		websocket.NetConn(ctx, ws, websocket.MessageBinary),
+		logger,
+	)
+	require.NoError(t, err)
+
+	coord, err := client.Coordinate(ctx)
+	require.NoError(t, err)
+
+	coordination := tailnet.NewRemoteCoordination(logger, coord, conn, agentID)
+	t.Cleanup(func() { _ = coordination.Close() })
+	return conn
+}

tailnet/test/integration/integration_internal_test.go

@@ -0,0 +1,194 @@
+package integration
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"os"
+	"os/exec"
+	"strconv"
+	"syscall"
+	"testing"
+
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"tailscale.com/tailcfg"
+
+	"cdr.dev/slog"
+	"cdr.dev/slog/sloggers/slogtest"
+	"github.com/coder/coder/v2/tailnet"
+	"github.com/coder/coder/v2/testutil"
+)
+
+var (
+	isChild            = flag.Bool("child", false, "Run tests as a child")
+	childTestID        = flag.Int("child-test-id", 0, "Which test is being run")
+	childCoordinateURL = flag.String("child-coordinate-url", "", "The coordinate url to connect back to")
+	childAgentID       = flag.String("child-agent-id", "", "The agent id of the child")
+)
+
+func TestMain(m *testing.M) {
+	if run := os.Getenv("CODER_TAILNET_TESTS"); run == "" {
+		_, _ = fmt.Println("skipping tests...")
+		return
+	}
+	if os.Getuid() != 0 {
+		_, _ = fmt.Println("networking integration tests must run as root")
+		return
+	}
+	flag.Parse()
+	os.Exit(m.Run())
+}
+
+var tests = []Test{{
+	Name:        "Normal",
+	DERPMap:     DERPMapTailscale,
+	Coordinator: CoordinatorInMemory,
+	Parent: Parent{
+		NetworkSetup: NetworkSetupDefault,
+		TailnetSetup: TailnetSetupDRPC,
+		Run: func(ctx context.Context, t *testing.T, opts ParentOpts) {
+			reach := opts.Conn.AwaitReachable(ctx, tailnet.IPFromUUID(opts.AgentID))
+			assert.True(t, reach)
+		},
+	},
+	Child: Child{
+		NetworkSetup: NetworkSetupDefault,
+		TailnetSetup: TailnetSetupDRPC,
+		Run: func(ctx context.Context, t *testing.T, opts ChildOpts) {
+			// wait until the parent kills us
+			<-make(chan struct{})
+		},
+	},
+}}
+
+//nolint:paralleltest
+func TestIntegration(t *testing.T) {
+	if *isChild {
+		logger := slogtest.Make(t, nil).Leveled(slog.LevelDebug)
+		ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitSuperLong)
+		t.Cleanup(cancel)
+
+		agentID, err := uuid.Parse(*childAgentID)
+		require.NoError(t, err)
+
+		test := tests[*childTestID]
+		test.Child.NetworkSetup(t)
+		dm := test.DERPMap(ctx, t)
+		conn := test.Child.TailnetSetup(ctx, t, logger, agentID, uuid.Nil, *childCoordinateURL, dm)
+		test.Child.Run(ctx, t, ChildOpts{
+			Logger:  logger,
+			Conn:    conn,
+			AgentID: agentID,
+		})
+		return
+	}
+
+	for id, test := range tests {
+		t.Run(test.Name, func(t *testing.T) {
+			ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitSuperLong)
+			t.Cleanup(cancel)
+
+			logger := slogtest.Make(t, nil).Leveled(slog.LevelDebug)
+			parentID, childID := uuid.New(), uuid.New()
+			dm := test.DERPMap(ctx, t)
+			_, coordURL := test.Coordinator(t, logger, dm)
+
+			child, waitChild := execChild(ctx, id, coordURL, childID)
+			test.Parent.NetworkSetup(t)
+			conn := test.Parent.TailnetSetup(ctx, t, logger, parentID, childID, coordURL, dm)
+			test.Parent.Run(ctx, t, ParentOpts{
+				Logger:   logger,
+				Conn:     conn,
+				ClientID: parentID,
+				AgentID:  childID,
+			})
+			child.Process.Signal(syscall.SIGINT)
+			<-waitChild
+		})
+	}
+}
+
+type Test struct {
+	// Name is the name of the test.
+	Name string
+
+	// DERPMap returns the DERP map to use for both the parent and child. It is
+	// called once at the beginning of the test.
+	DERPMap func(ctx context.Context, t *testing.T) *tailcfg.DERPMap
+	// Coordinator returns a running tailnet coordinator, and the url to reach
+	// it on.
+	Coordinator func(t *testing.T, logger slog.Logger, dm *tailcfg.DERPMap) (coord tailnet.Coordinator, url string)
+
+	Parent Parent
+	Child  Child
+}
+
+// Parent is the struct containing all of the parent specific configurations.
+// Functions are invoked in order of struct definition.
+type Parent struct {
+	// NetworkSetup is run before all test code. It can be used to setup
+	// networking scenarios.
+	NetworkSetup func(t *testing.T)
+
+	// TailnetSetup creates a tailnet network.
+	TailnetSetup func(
+		ctx context.Context, t *testing.T, logger slog.Logger,
+		id, agentID uuid.UUID, coordURL string, dm *tailcfg.DERPMap,
+	) *tailnet.Conn
+
+	Run func(ctx context.Context, t *testing.T, opts ParentOpts)
+}
+
+// Child is the struct containing all of the child specific configurations.
+// Functions are invoked in order of struct definition.
+type Child struct {
+	// NetworkSetup is run before all test code. It can be used to setup
+	// networking scenarios.
+	NetworkSetup func(t *testing.T)
+
+	// TailnetSetup creates a tailnet network.
+	TailnetSetup func(
+		ctx context.Context, t *testing.T, logger slog.Logger,
+		id, agentID uuid.UUID, coordURL string, dm *tailcfg.DERPMap,
+	) *tailnet.Conn
+
+	// Run runs the actual test. Parents and children run in separate processes,
+	// so it's important to ensure no communication happens over memory between
+	// run functions of parents and children.
+	Run func(ctx context.Context, t *testing.T, opts ChildOpts)
+}
+
+type ParentOpts struct {
+	Logger   slog.Logger
+	Conn     *tailnet.Conn
+	ClientID uuid.UUID
+	AgentID  uuid.UUID
+}
+
+type ChildOpts struct {
+	Logger  slog.Logger
+	Conn    *tailnet.Conn
+	AgentID uuid.UUID
+}
+
+func execChild(ctx context.Context, testID int, coordURL string, agentID uuid.UUID) (*exec.Cmd, <-chan error) {
+	ch := make(chan error)
+	binary := os.Args[0]
+	args := os.Args[1:]
+	args = append(args,
+		"--child=true",
+		"--child-test-id="+strconv.Itoa(testID),
+		"--child-coordinate-url="+coordURL,
+		"--child-agent-id="+agentID.String(),
+	)
+
+	cmd := exec.CommandContext(ctx, binary, args...)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	go func() {
+		ch <- cmd.Run()
+	}()
+	return cmd, ch
+}