linera-io/linera-protocol · error

Invalid options file format: \n {options_string}

Error message

Invalid options file format: \n {options_string}

What it means

The server's run function reads each validator options file and parses it with toml::from_str into ValidatorOptions. Parsing failures (bad TOML syntax, wrong types, unknown/missing fields such as server_config_path) panic with 'Invalid options file format' along with the full file contents. This runs during validator/proxy configuration generation, not during normal serving.

Source

Thrown at linera-service/src/server.rs:898

                .boxed()
                .await
                .unwrap()
                .unwrap();
        }

        ServerCommand::Generate {
            validators,
            committee,
            testing_prng_seed,
        } => {
            let mut config_validators = Vec::new();
            let mut rng = Box::<dyn CryptoRng>::from(testing_prng_seed);
            for options_path in validators {
                let options_string = fs_err::tokio::read_to_string(options_path)
                    .await
                    .expect("Unable to read validator options file");
                let options: ValidatorOptions = toml::from_str(&options_string)
                    .unwrap_or_else(|_| panic!("Invalid options file format: \n {options_string}"));
                let path = options.server_config_path.clone();
                let mut server = make_server_config(&path, &mut rng, options)
                    .expect("Unable to open server config file");
                Persist::persist(&mut server)
                    .await
                    .expect("Unable to write server config file");
                info!("Wrote server config {}", path.to_str().unwrap());
                println!(
                    "{},{}",
                    server.validator.public_key, server.validator.account_key
                );
                config_validators.push(Persist::into_value(server).validator);
            }
            if let Some(committee) = committee {
                let mut config = persistent::File::new(
                    &committee,
                    CommitteeConfig {
                        validators: config_validators,

View on GitHub (pinned to 6c226ddcb3)

Solutions

1. Validate the file parses as TOML first (e.g. python -c 'import tomllib;tomllib.load(open("opts.toml","rb"))' or toml2json)
2. Match ValidatorOptions' expected fields exactly (including server_config_path) as shown in the repo's example configs
3. Fix syntax errors reported by the panic message, which echoes the offending file contents
4. Prefer generating options files with the provided CLI/tooling instead of hand-writing them

Example fix

# before (opts.toml)
server_config_path = 1234   # wrong type

# after
server_config_path = "/path/to/server.config"

// Validate the options file before passing it to the server:
let raw = std::fs::read_to_string(options_path)?;
let _opts: ValidatorOptions = toml::from_str(&raw)
    .map_err(|e| anyhow::anyhow!("{options_path} is not a valid options file: {e}"))?;

When it happens

Trigger: Invoking the server run path with one or more --options/-o files whose TOML does not deserialize into ValidatorOptions: syntax errors, keys with wrong value types, or files that are actually JSON/YAML.

Common situations: Hand-editing a validator options template and breaking syntax (unclosed quotes/brackets); switching config tooling that emits a different format; renaming fields per newer docs while the binary expects the documented ValidatorOptions shape; trailing commas.

Related errors

• Failed to read server config
• Invalid RUST_LOG_FORMAT: `{format}`. Valid values are `json
• Fail to read server config
• invalid block export configuration
• invalid block export configuration: {message}

AI-assisted analysis of linera-io/linera-protocol@6c226ddcb3 (2026-08-22). Data as JSON: /api/errors/dd60d1decbc7389e. Report an issue: GitHub.