influxdata/influxdb · error · Error::NoLine

no line protocol string provided

Error message

no line protocol string provided

What it means

The influxdb3 `write` command's `NoLine` variant is thrown when no line protocol string was supplied as the positional argument (e.g., the user passed only flags or an empty string). Distinct from NoInput in that it specifically flags the missing LP line string.

Solutions

  1. Ensure a non-empty quoted line protocol string is passed as the final argument
  2. Check the shell variable containing LP is set and non-empty
  3. Fall back to `--file` or stdin when the string is not available

Example fix

// before
LP=""; influxdb3 write --database my-db "$LP"
// after
LP='cpu,host=a usage=0.5'; influxdb3 write --database my-db "$LP"
Defensive patterns

Strategy: validation

Validate before calling

// shell guard
if [[ -z "${1:-}" ]]; then
  echo "line protocol string is required as final argument" >&2; exit 1
fi

Prevention

When it happens

Trigger: Calling write with an empty string argument or omitting the LP positional while flags like `--database` are present and no stdin/file fallback provided input.

Common situations: Shell variable holding LP is empty (`influxdb3 write --database db "$LP"` with LP unset); scripting wrappers dropping the final argument.

Understand the failure class

Background: "no subcommand specified" and "... is required": CLI errors when a required argument is missing — this error's family across 13 libraries.

Related errors

AI-assisted analysis of influxdata/influxdb@06200ef96b (2026-09-19). Data as JSON: /api/errors/1ef0b5c7b52931a2. Report an issue: GitHub.

Appendix: source

Thrown at influxdb3_commands/src/write.rs:41

/// `--max-http-request-size` so a `write` command piped from a generator
/// that produces a stream larger than 10 MiB still succeeds out of the box.
const DEFAULT_MAX_REQUEST_SIZE: usize = 10 * 1024 * 1024;

/// Size of each blocking `read()` from the input source (file / stdin).
const READ_SIZE: usize = 4 * 1024 * 1024;

#[derive(Debug, thiserror::Error)]
pub enum Error {
    #[error(transparent)]
    Client(#[from] influxdb3_client::Error),

    #[error("error reading file: {0}")]
    Io(#[from] io::Error),

    #[error("No input from stdin detected, no string was passed in, and no file path was given")]
    NoInput,

    #[error("no line protocol string provided")]
    NoLine,

    #[error(
        "ensure that a single protocol line string is provided as the final \
        argument, enclosed in quotes"
    )]
    MoreThanOne,
}

pub type Result<T> = std::result::Result<T, Error>;

#[derive(Debug, Parser)]
#[clap(visible_alias = "w", trailing_var_arg = true)]
pub struct Config {
    /// Common InfluxDB 3 server config
    #[clap(flatten)]
    influxdb3_config: InfluxDb3Config,

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