Adjust how error message is caught and displayed

ui/stream/exception.js

@@ -15,7 +15,7 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-export default class Exception {
+export default class Exception extends Error {
   /**
    * constructor
    *
@@ -24,17 +24,8 @@ export default class Exception {
    *
    */
   constructor(message, temporary) {
-    this.message = message;
+    super(message);
+
     this.temporary = temporary;
   }
-
-  /**
-   * Return the error string
-   *
-   * @returns {string} Error message
-   *
-   */
-  toString() {
-    return this.message;
-  }
 }

ui/stream/reader.js

@@ -222,12 +222,23 @@ export class Multiple {
    *
    */
   close() {
+    return this.closeWithReason("Reader is closed");
+  }
+
+  /**
+   * close current reading
+   *
+   * @param {string} reason Reason
+   *
+   */
+  closeWithReason(reason) {
     if (this.closed) {
       return;
     }
 
     this.closed = true;
-    this.subscribe.reject(new Exception("Reader is closed", false));
+    this.subscribe.reject(new Exception(reason, false));
+    this.subscribe.disable(reason);
   }
 
   /**
@@ -317,17 +328,23 @@ export class Reader {
    *
    */
   close() {
+    return this.closeWithReason("Reader is closed");
+  }
+
+  /**
+   * close current reading
+   *
+   * @param {string} reason Reason
+   *
+   */
+  closeWithReason(reason) {
     if (this.closed) {
       return;
     }
 
     this.closed = true;
-    this.buffers.reject(
-      new Exception(
-        "Reader is closed, and thus " + "cannot be operated on",
-        false
-      )
-    );
+    this.buffers.reject(new Exception(reason, false));
+    this.buffers.disable(reason);
 
     return this.multiple.close();
   }

ui/stream/sender.js

@@ -66,11 +66,7 @@ export class Sender {
 
     this.subscribe.reject(new Exception("Sender has been closed", false));
 
-    try {
-      await this.sendingPoc;
-    } catch (e) {
-      // Do nothing
-    }
+    this.sendingPoc.catch(() => {});
 
     this.reject(new Exception("Sending has been cancelled", true));
   }

ui/stream/subscribe.js

@@ -29,6 +29,7 @@ export class Subscribe {
     this.res = null;
     this.rej = null;
     this.pending = [];
+    this.disabled = null;
   }
 
   /**
@@ -78,6 +79,10 @@ export class Subscribe {
    *
    */
   subscribe() {
+    if (this.disabled) {
+      throw new Exception(this.disabled, false);
+    }
+
     if (this.pending.length > 0) {
       let p = this.pending.shift();
 
@@ -111,4 +116,14 @@ export class Subscribe {
       };
     });
   }
+
+  /**
+   * Disable current subscriber when all internal data is readed
+   *
+   * @param {string} reason Reason of the disable
+   *
+   */
+  disable(reason) {
+    this.disabled = reason;
+  }
 }