block/buzz · error · IngestError::Rejected

channel name is required

Error message

channel name is required

What it means

Thrown when a kind:9002 "name" tag value canonicalizes to an empty string via buzz_core::channel::canonical_channel_name. This catches names made entirely of characters that are display prefixes (e.g. "#", "##") which are stripped during canonicalization, leaving nothing. The check exists so a rename can never blank out a channel name.

Source

Thrown at crates/buzz-relay/src/handlers/side_effects.rs:540

                        }
                        None => {
                            return Err(anyhow::anyhow!("archived tag must have a value"));
                        }
                    }
                }
            }

            // Validate channel names before storage. A name made entirely of
            // display-prefix hashes becomes empty after canonicalization.
            for t in event.tags.iter() {
                if t.kind().to_string() == "name" {
                    match t.content() {
                        Some(v)
                            if !buzz_core::channel::canonical_channel_name(v)
                                .trim()
                                .is_empty() => {}
                        _ => {
                            return Err(anyhow::anyhow!("channel name is required"));
                        }
                    }
                }
            }

            // Validate visibility values before storage.
            for t in event.tags.iter() {
                if t.kind().to_string() == "visibility" {
                    match t.content() {
                        Some("open") | Some("private") => {}
                        Some(v) => {
                            return Err(anyhow::anyhow!(
                                "invalid visibility value: {v} (must be \"open\" or \"private\")"
                            ));
                        }
                        None => {
                            return Err(anyhow::anyhow!("visibility tag must have a value"));
                        }

View on GitHub (pinned to f956e6fe06)

Solutions

1. Send a name containing at least one non-prefix character, e.g. ["name", "general"] without the leading '#'.
2. Trim and validate the input client-side: reject names whose canonical form is empty before publishing.
3. If the intent was to leave the name unchanged, omit the name tag from the 9002 event.

Example fix

// before — UI prefixes '#' and user typed nothing but '#'
{ kind: 9002, tags: [["h", ch], ["name", `#${userInput}`]] } // userInput = "#" → "##"

// after
const raw = userInput.replace(/^#+/, "").trim();
if (raw) {
  { kind: 9002, tags: [["h", ch], ["name", raw]] };
}

// Mirror the relay's canonicalization before publishing a rename
function canonicalChannelName(raw: string): string {
  return raw.replace(/^#+/, "").trim().toLowerCase().replace(/[\s_]+/g, "-").replace(/[^a-z0-9-]/g, "");
}

const canon = canonicalChannelName(nameInput);
if (!canon) throw new Error("Channel name is empty after removing display prefix");
const tags = [["h", channelId], ["name", nameInput.trim()]];

function isNonEmptyChannelName(raw: string): boolean {
  // names made only of display-prefix hashes canonicalize to empty
  return raw.replace(/^#+/, "").trim().length > 0;
}

try {
  await sdk.publish(editEvent);
} catch (e) {
  if (String(e).includes("channel name is required")) {
    form.setError("name", "Name needs at least one non-# character");
  } else throw e;
}

When it happens

Trigger: Publishing [["name", "###"], ["name", ""], ["name", "#"]], or a name consisting only of whitespace/hash prefix characters in a kind:9002 event.

Common situations: UI passing an untrimmed input where the user typed only '#'; pre-pending '#' to channel names client-side and then sending names like '#general' where the user typed just '#'; renaming from a template variable that rendered empty.

Related errors

• kind:9002 must include at least one metadata tag (name, abou
• invalid archived value: {v} (must be "true" or "false")
• archived tag must have a value
• invalid visibility value: {v} (must be "open" or "private")
• visibility tag must have a value

AI-assisted analysis of block/buzz@f956e6fe06 (2026-08-16). Data as JSON: /api/errors/4c0675ef7aaa649d. Report an issue: GitHub.