redis/jedis · error · JedisValidationException

client info cannot contain spaces, newlines or special…

Error message

client info cannot contain spaces, newlines or special characters.

What it means

validateClientInfo() enforces that every character of the CLIENT SETINFO/setName value is a printable ASCII character ('!' through '~'). Spaces, newlines, and other special characters would corrupt the client-info string on the server, so JedisValidationException is thrown.

Solutions

Sanitize the string: replace all chars outside [!-~] with a safe substitute (e.g. '_') before calling
Validate with a regex like [!-~]+ and reject/transform invalid input early
Encode metadata as a single token, e.g. 'my_app_dev' instead of 'my app (dev)'

Example fix

// before
connection.setClientInfo(appName + " " + env); // contains space
// after
String info = (appName + "_" + env).replaceAll("[^!-~]", "_");
connection.setClientInfo(info);

Defensive patterns

Strategy: validation

Validate before calling

static final Pattern SAFE = Pattern.compile("[!-~]+");
if (!SAFE.matcher(info).matches()) throw new IllegalArgumentException("client info must be printable ASCII without spaces");

Type guard

static boolean isSafeClientInfo(String s) { return s != null && s.chars().allMatch(c -> c >= '!' && c <= '~'); }

Try / catch

try { conn.setClientInfo(info); } catch (JedisValidationException e) { log.warn("invalid client info rejected: " + info); }

Prevention

Sanitize labels derived from process/thread/user input
Use '_' instead of spaces in client info
Validate at config time, not at connect time

When it happens

Trigger: Calling connection.setClientInfo(...) or client-name APIs with values containing spaces, tabs, CR/LF, or non-ASCII characters (e.g. hostnames with dots are fine, but 'my app (dev)' is not).

Common situations: Deriving client info from process names, thread names, or user-supplied labels that contain spaces; encoding app metadata with separators like '|' or ' '; forgetting to sanitize before set.

Understand the failure class

Background: "Invalid ... format", "must be in format X", "does not look like a ..." — invalid argument format errors across CLI tools and libraries — this error's family across 17 libraries.

Related errors

AI-assisted analysis of redis/jedis@6dac31d4c2 (2026-09-08). Data as JSON: /api/errors/66d45f9d385178b7. Report an issue: GitHub.

Appendix: source

Thrown at src/main/java/redis/clients/jedis/Connection.java:840

        responses.add(readProtocolWithCheckingBroken());
      } catch (JedisDataException e) {
        responses.add(e);
      }
    }
    return responses;
  }

  /**
   * Check if the client name libname, libver, characters are legal
   * @param info the name
   * @return Returns true if legal, false throws exception
   * @throws JedisException if characters illegal
   */
  private static boolean validateClientInfo(String info) {
    for (int i = 0; i < info.length(); i++) {
      char c = info.charAt(i);
      if (c < '!' || c > '~') {
        throw new JedisValidationException(
            "client info cannot contain spaces, " + "newlines or special characters.");
      }
    }
    return true;
  }

  /**
   * Initialize this connection using the {@link JedisClientConfig} captured at construction.
   * <p>
   * Internal lifecycle step: invoked once by {@link Connection.Builder#build()} for direct
   * callers, and once by {@link ConnectionFactory#initialize(Connection)} for pooled
   * connections. There is no public construction path that produces an uninitialized-but-
   * configured {@code Connection}, so this method has no out-of-package use case.
   */
  void initializeFromClientConfig() {
    this.initializeFromClientConfig(clientConfig);
  }

View on GitHub (pinned to 6dac31d4c2)