Start working on blender-render command

The command doesn't actually execute anything yet.

internal/manager/job_compilers/job_compilers_test.go

@@ -117,6 +117,7 @@ func TestSimpleBlenderRenderHappy(t *testing.T) {
 		"exe":        "{blender}",
 		"blendfile":  settings["filepath"].(string),
 		"args":       expectCliArgs,
+		"argsBefore": make([]interface{}, 0),
 	}, t0.Commands[0].Parameters)
 
 	tVideo := aj.Tasks[4] // This should be a video encoding task

internal/manager/job_compilers/scripts/simple_blender_render.js

@@ -93,6 +93,7 @@ function authorRenderTasks(settings, renderDir, renderOutput) {
         const task = author.Task(`render-${chunk}`, "blender");
         const command = author.Command("blender-render", {
             exe: settings.blender_cmd,
+            argsBefore: [],
             blendfile: settings.filepath,
             args: [
                 "--render-output", path.join(renderDir, path.basename(renderOutput)),

internal/worker/command_blender.go

@@ -0,0 +1,72 @@
+package worker
+
+/* ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * Original Code Copyright (C) 2022 Blender Foundation.
+ *
+ * This file is part of Flamenco.
+ *
+ * Flamenco is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later
+ * version.
+ *
+ * Flamenco is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ * A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * Flamenco.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * ***** END GPL LICENSE BLOCK ***** */
+
+/* This file contains the commands in the "blender" type group. */
+
+import (
+	"context"
+	"fmt"
+	"os/exec"
+
+	"github.com/rs/zerolog"
+	"gitlab.com/blender/flamenco-ng-poc/pkg/api"
+)
+
+type BlenderSettings struct {
+	exe        string   // Expansion of `{blender}`: executable path + its CLI parameters defined by the Manager.
+	argsBefore []string // Additional CLI arguments defined by the job compiler script, to go before the blend file name.
+	blendfile  string   // Path of the file to open.
+	args       []string // Additional CLI arguments defined by the job compiler script, to go after the blend file name.
+}
+
+// cmdBlender executes the "blender-render" command.
+func (ce *CommandExecutor) cmdBlenderRender(ctx context.Context, logger zerolog.Logger, taskID string, cmd api.Command) error {
+	settings := BlenderSettings{
+		exe:        cmd.Settings["exe"].(string),
+		argsBefore: cmd.Settings["argsBefore"].([]string),
+		blendfile:  cmd.Settings["blendfile"].(string),
+		args:       cmd.Settings["args"].([]string),
+	}
+	if settings.exe == "" {
+		logger.Warn().Interface("command", cmd).Msg("missing 'exe' setting")
+		return fmt.Errorf("missing 'exe' setting: %+v", cmd)
+	}
+	if settings.blendfile == "" {
+		logger.Warn().Interface("command", cmd).Msg("missing 'blendfile' setting")
+		return fmt.Errorf("missing 'blendfile' setting: %+v", cmd)
+	}
+
+	cliArgs := make([]string, 0)
+	cliArgs = append(cliArgs, settings.argsBefore...)
+	cliArgs = append(cliArgs, settings.blendfile)
+	cliArgs = append(cliArgs, settings.args...)
+	execCmd := exec.CommandContext(ctx, settings.exe, cliArgs...)
+	logger.Info().
+		Str("cmdName", cmd.Name).
+		Str("execCmd", execCmd.String()).
+		Msg("going to execute Blender")
+
+	// if err := ce.listener.LogProduced(ctx, taskID, fmt.Sprintf("echo: %q", messageStr)); err != nil {
+	// 	return err
+	// }
+	return nil
+}

internal/worker/command_exe.go

@@ -70,6 +70,7 @@ func NewCommandExecutor(listener CommandListener, timeService TimeService) *Comm
 	ce.registry = map[string]commandCallable{
 		"echo":           ce.cmdEcho,
 		"sleep":          ce.cmdSleep,
+		"blender-render": ce.cmdBlenderRender,
 	}
 
 	return ce