bugfix: say text continued to play after task was killed

lib/tasks/say.js

@@ -20,24 +20,27 @@ class TaskSay extends Task {
     await super.exec(cs);
     this.ep = ep;
     try {
-      const filepath = [];
+      // synthesize all of the text elements
+      const filepath = (await Promise.all(this.text.map(async(text) => {
+        const fp = await synthAudio({
+          text,
+          vendor: cs.speechSynthesisVendor,
+          language: cs.speechSynthesisLanguage,
+          voice: cs.speechSynthesisVoice,
+          salt: cs.callSid
+        }).catch((err) => this.logger.error(err, 'Error synthesizing text'));
+        if (fp) cs.trackTmpFile(fp);
+        return fp;
+      })))
+        .filter((fp) => fp && fp.length);
+
+      this.logger.debug({filepath}, 'synthesized files for tts');
+
       while (!this.killed && this.loop-- && this.ep.connected) {
         let segment = 0;
         do {
-          if (filepath.length <= segment) {
-            const opts = Object.assign({
-              text: this.text[segment],
-              vendor: cs.speechSynthesisVendor,
-              language: cs.speechSynthesisLanguage,
-              voice: cs.speechSynthesisVoice,
-              salt: cs.callSid
-            }, this.synthesizer);
-            const path = await synthAudio(opts);
-            filepath.push(path);
-            cs.trackTmpFile(path);
-          }
           await ep.play(filepath[segment]);
-        } while (++segment < this.text.length);
+        } while (!this.killed && ++segment < filepath.length);
       }
     } catch (err) {
       this.logger.info(err, 'TaskSay:exec error');