coder/agent/agentproc/api.go

package agentproc

import (
	"encoding/json"
	"errors"
	"fmt"
	"net/http"

	"github.com/go-chi/chi/v5"

	"cdr.dev/slog/v3"
	"github.com/coder/coder/v2/agent/agentexec"
	"github.com/coder/coder/v2/coderd/httpapi"
	"github.com/coder/coder/v2/codersdk"
	"github.com/coder/coder/v2/codersdk/workspacesdk"
)

// API exposes process-related operations through the agent.
type API struct {
	logger  slog.Logger
	manager *manager
}

// NewAPI creates a new process API handler.
func NewAPI(logger slog.Logger, execer agentexec.Execer, updateEnv func(current []string) (updated []string, err error)) *API {
	return &API{
		logger:  logger,
		manager: newManager(logger, execer, updateEnv),
	}
}

// Close shuts down the process manager, killing all running
// processes.
func (api *API) Close() error {
	return api.manager.Close()
}

// Routes returns the HTTP handler for process-related routes.
func (api *API) Routes() http.Handler {
	r := chi.NewRouter()
	r.Post("/start", api.handleStartProcess)
	r.Get("/list", api.handleListProcesses)
	r.Get("/{id}/output", api.handleProcessOutput)
	r.Post("/{id}/signal", api.handleSignalProcess)
	return r
}

// handleStartProcess starts a new process.
func (api *API) handleStartProcess(rw http.ResponseWriter, r *http.Request) {
	ctx := r.Context()

	var req workspacesdk.StartProcessRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		httpapi.Write(ctx, rw, http.StatusBadRequest, codersdk.Response{
			Message: "Request body must be valid JSON.",
			Detail:  err.Error(),
		})
		return
	}

	if req.Command == "" {
		httpapi.Write(ctx, rw, http.StatusBadRequest, codersdk.Response{
			Message: "Command is required.",
		})
		return
	}

	proc, err := api.manager.start(req)
	if err != nil {
		httpapi.Write(ctx, rw, http.StatusInternalServerError, codersdk.Response{
			Message: "Failed to start process.",
			Detail:  err.Error(),
		})
		return
	}

	httpapi.Write(ctx, rw, http.StatusOK, workspacesdk.StartProcessResponse{
		ID:      proc.id,
		Started: true,
	})
}

// handleListProcesses lists all tracked processes.
func (api *API) handleListProcesses(rw http.ResponseWriter, r *http.Request) {
	ctx := r.Context()

	infos := api.manager.list()
	httpapi.Write(ctx, rw, http.StatusOK, workspacesdk.ListProcessesResponse{
		Processes: infos,
	})
}

// handleProcessOutput returns the output of a process.
func (api *API) handleProcessOutput(rw http.ResponseWriter, r *http.Request) {
	ctx := r.Context()

	id := chi.URLParam(r, "id")
	proc, ok := api.manager.get(id)
	if !ok {
		httpapi.Write(ctx, rw, http.StatusNotFound, codersdk.Response{
			Message: fmt.Sprintf("Process %q not found.", id),
		})
		return
	}

	output, truncated := proc.output()
	info := proc.info()

	httpapi.Write(ctx, rw, http.StatusOK, workspacesdk.ProcessOutputResponse{
		Output:    output,
		Truncated: truncated,
		Running:   info.Running,
		ExitCode:  info.ExitCode,
	})
}

// handleSignalProcess sends a signal to a running process.
func (api *API) handleSignalProcess(rw http.ResponseWriter, r *http.Request) {
	ctx := r.Context()

	id := chi.URLParam(r, "id")

	var req workspacesdk.SignalProcessRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		httpapi.Write(ctx, rw, http.StatusBadRequest, codersdk.Response{
			Message: "Request body must be valid JSON.",
			Detail:  err.Error(),
		})
		return
	}

	if req.Signal == "" {
		httpapi.Write(ctx, rw, http.StatusBadRequest, codersdk.Response{
			Message: "Signal is required.",
		})
		return
	}

	if req.Signal != "kill" && req.Signal != "terminate" {
		httpapi.Write(ctx, rw, http.StatusBadRequest, codersdk.Response{
			Message: fmt.Sprintf(
				"Unsupported signal %q. Use \"kill\" or \"terminate\".",
				req.Signal,
			),
		})
		return
	}

	if err := api.manager.signal(id, req.Signal); err != nil {
		switch {
		case errors.Is(err, errProcessNotFound):
			httpapi.Write(ctx, rw, http.StatusNotFound, codersdk.Response{
				Message: fmt.Sprintf("Process %q not found.", id),
			})
		case errors.Is(err, errProcessNotRunning):
			httpapi.Write(ctx, rw, http.StatusConflict, codersdk.Response{
				Message: fmt.Sprintf(
					"Process %q is not running.", id,
				),
			})
		default:
			httpapi.Write(ctx, rw, http.StatusInternalServerError, codersdk.Response{
				Message: "Failed to signal process.",
				Detail:  err.Error(),
			})
		}
		return
	}

	httpapi.Write(ctx, rw, http.StatusOK, codersdk.Response{
		Message: fmt.Sprintf(
			"Signal %q sent to process %q.", req.Signal, id,
		),
	})
}