• Title: Instance options
  • Start Date: 2022-03-01

# Instance options

# 1. Summary

The instance options let the users configure Meilisearch when launching the search engine using

  • environment variables
  • command-line options

An example when setting an environment variable to change the folder path where the Meilisearch data are stored:

export MEILI_DB_PATH=./meilifiles
./meilisearch

Same behavior using the command-line option:

./meilisearch --db-path ./meilifiles

# 2. Motivation

When Meilisearch is launched, the default configuration may not meet the specific needs of users. Meilisearch exposes configurable options to allow users to fine-tune the behavior of the search engine.

# 3. Functional Specification

The users can configure Meilisearch when launching the search engine using

  • environment variables. Ex: --db-path
  • command-line options or CLI options. Ex: MEILI_DB_PATH

There are 2 categories of CLI (command-line interface) options:

  • the ones that expect a value. Ex: --db-path "./my_path".
  • the ones that don't expect any value, called also "flags". Ex: --no-analytics. Their implicit values are booleans.

# 3.1. Some specific behaviors

# 3.1.1. Priority between CLI options and environment variables

Command-line options take precedence over environment variables. If the same configuration option is specified both as a command-line option and as an environment variable, Meilisearch will use the command-line option and its respective value.

# 3.1.2. Flags: accepted values for the corresponding environment variable

The options that do not expect any value when using the command-line option accepts the following value when using the corresponding environment variable: n, no, f, false, off, and 0 as false. An absent environment variable will also be considered as false. Everything else is considered true.

Example with the option to make SSL mandatory:

  • export MEILI_SSL_REQUIRE_AUTH=yes means that mandatory SSL is enabled.
  • export MEILI_SSL_REQUIRE_AUTH=off means that mandatory SSL is disabled.
  • No variable set means that mandatory SSL is disabled.

# 3.2. Error behavior

  1. Some configuration options must specify a value to be valid. Using such a command-line option or an environment variable without specifying a value will throw an error and interrupt the launch process.

Example:

❌ Wrong

./meilisearch --db-path

error: The argument '--db-path <DB_PATH>' requires a value but none was supplied

✅ Correct

./meilisearch --db-path ./meilifiles
  1. Some command-line options take an implicit boolean as a value. In this case, the users should not set any value when using the option.

❌ Wrong

./meilisearch --ssl-require-auth yes

error: Found argument 'yes' which wasn't expected, or isn't valid in this context

✅ Correct

./meilisearch --ssl-require-auth

The expected behavior of each flag is described in the list above.

# 3.3. Exhaustive list of options

# 3.3.1. Database path

Environment variable: MEILI_DB_PATH CLI option: --db-path Default value: "data.ms/" Expected value: a filepath

Designates the location where database files will be created and retrieved.

# 3.3.2. Environment

Environment variable: MEILI_ENV CLI option: --env Default value: development Expected value: production or development

Configures the instance's environment. Value must be either production or development.

production:

  • Setting a master key of at least 16 bytes is mandatory
  • The search preview interface is disabled

development:

  • Setting a master key is optional
  • Setting a master key of at least 16 bytes is optional
  • Search preview is enabled

# 3.3.3. HTTP address & port binding

Environment variable: MEILI_HTTP_ADDR CLI option: --http-addr Default value: "localhost:7700" Expected value: an HTTP address and port

Sets the HTTP address and port Meilisearch will use.

# 3.3.4. Master key

Environment variable: MEILI_MASTER_KEY CLI option: --master-key Default value: None Expected value: an alphanumeric string

Sets the instance's master key, automatically protecting all routes except GET /health. This means you will need an API key to access endpoints such as POST /search and GET /documents.

You must supply an alphanumeric string when using this option.

If no master key is provided in a development environment, all routes will be unprotected and publicly accessible.

# 3.3.4.1. Error and Warning messages

Providing a master key of at least 16 bytes is mandatory when --env is set to production; if none is given, Meilisearch will throw an error and refuse to launch.

Error: You must provide a master key to secure your instance in a production environment. It can be specified via the MEILI_MASTER_KEY environment variable or the --master-key launch option.

We generated a secure master key for you (you can safely use this token):

>> --master-key `:suggestedMasterKey` <<

Providing a master key of at least 16 bytes is mandatory when --env is set to production; if it is given but too short then, Meilisearch will throw an error and refuse to launch.

Error: The master key must be at least 16 bytes in a production environment. The provided key is only `:numBytes` bytes.

We generated a secure master key for you (you can safely use this token):

>> --master-key `:suggestedMasterKey` <<

Providing a master key of less than 16 bytes when --env is set to development displays a warning message.

Meilisearch started with a master key considered unsafe for use in a production environment.

A master key of at least 16 bytes will be required when switching to a production environment.

We generated a new secure master key for you (you can safely use this token):

>> --master-key `:suggestedMasterKey` <<

Restart Meilisearch with the argument above to use this new and secure master key.

Not providing a master key when --env is set to development displays a warning message.

No master key was found. The server will accept unidentified requests.

A master key of at least 16 bytes will be required when switching to a production environment.

If you need protection in a development environment, we generated a secure master key for you (you can safely use this token):

>> --master-key `:suggestedMasterKey` <<

Restart Meilisearch with the argument above to use this new and secure master key.

# 3.3.5. Disable analytics

Environment variable: MEILI_NO_ANALYTICS CLI option: --no-analytics Default: Enabled

⚠️ This command-line option does not take any values. Assigning a value will throw an error.

Deactivates Meilisearch's built-in telemetry collect when enabled.

# 3.3.6. Dump directory

Environment variable: MEILI_DUMP_DIR CLI option: --dump-dir Default value: dumps/ Expected value: a filepath pointing to a valid directory

Sets the directory where Meilisearch will create dump files. If the directory does not exist when a dump is generated it will be created.

# 3.3.7. Import dump

Environment variable: MEILI_IMPORT_DUMP CLI option: --import-dump Default value: none Expected value: a filepath pointing to a .dump file

Imports the dump file located at the specified path. Path must point to a .dump file.

Meilisearch will only launch once the dump data has been fully indexed.

More regarding dump behaviors in this spec (opens new window).

# 3.3.8. Ignore missing dump

Environment variable: MEILI_IGNORE_MISSING_DUMP CLI option: --ignore-missing-dump Default: Disabled

⚠️ This command-line option does not take any values. Assigning a value will throw an error.

Prevents a Meilisearch instance from throwing an error when --import-dump does not point to a valid dump file.

This command will throw an error if --import-dump is not defined.

More information in this section of the spec (opens new window).

# 3.3.9. Ignore dump if DB exists

Environment variable: MEILI_IGNORE_DUMP_IF_DB_EXISTS CLI option: --ignore-dump-if-db-exists Default: Disabled

⚠️ This command-line option does not take any values. Assigning a value will throw an error.

Prevents a Meilisearch instance with an existing database from throwing an error when using --import-dump. Instead, the dump will be ignored and Meilisearch will launch using the existing database.

This command will throw an error if --import-dump is not defined.

More information in this section of the spec (opens new window).

# 3.3.10. Log level

Environment variable: MEILI_LOG_LEVEL CLI option: --log-level Default value: 'INFO' Expected value: one of ERROR, WARN, INFO, DEBUG, TRACE, or OFF

Defines how much detail should be present in Meilisearch's logs.

# 3.3.11. Payload limit size

Environment variable: MEILI_HTTP_PAYLOAD_SIZE_LIMIT CLI option: --http-payload-size-limit Default value: 104857600 (~100MB) Expected value: an integer (104857600) or a human readable size (100Mb)

Sets the maximum size of accepted payloads. Value must be given in bytes or explicitly stating a base unit. For example, the default value can be written as 107374182400, '107.7Gb', or '107374 Mb'.

# 3.3.12. Schedule snapshot creation

Environment variable: MEILI_SCHEDULE_SNAPSHOT CLI option: --schedule-snapshot Default when absent: Disabled Optional value: an integer

⚠️ This command-line option takes an optional integer value. Passing the flag with no value implies the default value of 86400.

  • Omitting the flag, not defining MEILI_SCHEDULE_SNAPSHOT, or specifying schedule_snapshot=false in the configuration file disables the scheduled snapshots, and is the default behavior.
  • Passing the flag without a value or specifying schedule_snapshot=true in the configuration file enables the scheduled snapshot with the default interval of 86400 seconds between each snapshot.
  • Passing the flag with an integer value, defining the MEILI_SCHEDULE_SNAPSHOT to an integer value, or specifying schedule_snapshot=x with x an integer value in the configuration file enables the scheduled snapshots with an interval between each snapshot of the specified integer value, in seconds.

# 3.3.13. Snapshot destination

Environment variable: MEILI_SNAPSHOT_DIR CLI option: --snapshot-dir Default value: snapshots/ Expected value: a filepath pointing to a valid directory

Sets the directory where Meilisearch will store snapshots. If the directory does not exist when a snapshot is generated it will be created.

# 3.3.14. Import snapshot

Environment variable: MEILI_IMPORT_SNAPSHOT CLI option: --import-snapshot Default value: None Expected value: a filepath pointing to a snapshot file

Launches Meilisearch after importing a previously-generated snapshot at the given filepath.

This command will throw an error if:

  • A database already exists
  • No valid snapshot can be found in the specified path

This behavior can be modified with the --ignore-snapshot-if-db-exists and --ignore-missing-snapshot options, respectively.

# 3.3.15. Ignore missing snapshot

Environment variable: MEILI_IGNORE_MISSING_SNAPSHOT CLI option: --ignore-missing-snapshot Default: Disabled

⚠️ This command-line option does not take any values. Assigning a value will throw an error.

Prevents a Meilisearch instance from throwing an error when --import-snapshot does not point to a valid snapshot file.

This command will throw an error if --import-snapshot is not defined.

# 3.3.16. Ignore snapshot if DB exists

Environment variable: MEILI_IGNORE_SNAPSHOT_IF_DB_EXISTS CLI option: --ignore-snapshot-if-db-exists Default: Disabled

⚠️ This command-line option does not take any values. Assigning a value will throw an error.

Prevents a Meilisearch instance with an existing database from throwing an error when using --import-snapshot. Instead, the snapshot will be ignored and Meilisearch will launch using the existing database.

This command will throw an error if --import-snapshot is not defined.

# 3.3.17. Max memory usage when indexing

Environment variable: MEILI_MAX_INDEXING_MEMORY CLI option: --max-indexing-memory Default value: 2/3 of the available RAM of the machine Expected value: an integer (104857600) or a human readable size (100Mb)

Set the maximum size of the RAM used by Meilisearch when indexing. By default, Meilisearch adapts its behavior to make the indexation use at maximum two-thirds of the available resources.

Value must be given in bytes or explicitly stating a base unit. For example, the default value can be written as 107374182400, '107.7Gb', or '107374 Mb'.

⚠️ WARNINGS

  • We do not recommend setting the full RAM size of your machine. For example, when running Meilisearch on a machine with 4GB of RAM, do not set this options to 4Gb
  • This command-line option does not perfectly ensure the RAM usage but helps you manage multiple Meilisearch engines on the same machine (for example, using Kubernetes). The search engine cannot guarantee the exact usage of the RAM.
  • If the number set is higher than the real available RAM in the machine, we cannot prevent Meilisearch from crashing.

# 3.3.18. Max indexing threads

Environment variable: MEILI_MAX_INDEXING_THREADS CLI option: --max-indexing-threads Default value: half of the available threads of the machine Expected value: an integer

Sets the maximum number of threads available to use during the indexation.

By default, in machines with multi-core processors, the indexer avoids using more than half of the available processing units. For example, if your machine has twelve cores, the indexer will try to use six of them at most. This ensures Meilisearch is always ready to perform searches, even while you are updating an index. Users have to be aware that requiring the totality of the threads for the indexation can lead to a huge impact on the search experience.

Obviously, multi-threading is not possible in machines with only one processor core.

If the number set is higher than the real number of core available in the machine, Meilisearch will use the maximum number of available cores.

# 3.3.19. SSL authentication path

Environment variable: MEILI_SSL_AUTH_PATH CLI option: --ssl-auth-path Default value: None Expected value: a filepath

Enables client authentication in the specified path.

# 3.3.20. SSL certificates path

Environment variable: MEILI_SSL_CERT_PATH CLI option: --ssl-cert-path Default value: None Expected value: a filepath pointing to a valid SSL certificate

Sets the server's SSL certificates.

Value must be a path to PEM-formatted certificates. The first certificate should certify the KEYFILE supplied by --ssl-key-path. The last certificate should be a root CA.

# 3.3.21. SSL key path

Environment variable: MEILI_SSL_KEY_PATH CLI option: --ssl-key-path Default value: None Expected value: a filepath pointing to a valid SSL keyfile

Sets the server's SSL keyfiles.

Value must be a path to an RSA private key or PKCS8-encoded private key, both in PEM format.

# 3.3.22. SSL OCSP path

Environment variable: MEILI_SSL_OCSP_PATH CLI option: --ssl-ocsp-path Default value: None Expected value: a filepath pointing to a valid OCSP certificate

Sets the server's OCSP file. Optional

Reads DER-encoded OCSP response from OCSPFILE and staple to certificate.

# 3.3.23. SSL require auth

Environment variable: MEILI_SSL_REQUIRE_AUTH CLI option: --ssl-require-auth Default: Disabled

⚠️ This command-line option does not take any values. Assigning a value will throw an error.

Makes SSL authentication mandatory.

Sends a fatal alert if the client does not complete client authentication.

# 3.3.24. SSL resumption

Environment variable: MEILI_SSL_RESUMPTION CLI option: --ssl-resumption Default: Disabled

⚠️ This command-line option does not take any values. Assigning a value will throw an error.

Activates SSL session resumption.

# 3.3.25. SSL tickets

Environment variable: MEILI_SSL_TICKETS CLI option: --ssl-tickets Default: Disabled

⚠️ This command-line option does not take any values. Assigning a value will throw an error.

Activates SSL tickets.

# 3.3.26. Config file path

Environment variable: MEILI_CONFIG_FILE_PATH CLI option: --config-file-path Default: ./config.toml

Define the config file to load at Meilisearch launch.

See Configuration File specification details.

# 3.3.27. Experimental enable Metrics

Environment variable: MEILI_EXPERIMENTAL_ENABLE_METRICS CLI option: --experimental-enable-metrics Default: Disabled

⚠️ This command-line option does not take any values. Assigning a value will throw an error.

Activate the /metrics endpoint to collect Meilisearch metrics for monitoring purposes. See 0174-metrics-api.md.

# 3.3.28. Experimental Reduce Indexing Memory Usage

Environment variable: MEILI_EXPERIMENTAL_REDUCE_INDEXING_MEMORY_USAGE CLI option: --experimental-reduce-indexing-memory-usage Default: Disabled

⚠️ This command-line option does not take any values. Assigning a value will throw an error.

Enables the MDB_WRITEMAP option of LMDB, making the internal key-value store use much less RAM than usual.

# 3.3.29. Task webhook url

Environment variable: MEILI_TASK_WEBHOOK_URL CLI option: --task-webhook-url Default: Disabled Expected value: an url to your server

Sets the URL where Meilisearch will send a notification every time it processes a batch of tasks. ⚠️ If the URL is not correctly formatted, it'll throw an error before starting. ⚠️ If the URL is correctly formatted but doesn't point to a valid server, Meilisearch won't return an error but will log one every time it processes a batch of tasks.

# 3.3.30. Task webhook authorization header

Environment variable: MEILI_TASK_WEBHOOK_AUTHORIZATION_HEADER CLI option: --task-webhook-authorization-header Default: Disabled Expected value: a string representing the value of the authorization header you want to send with the processed tasks

Sets the authorization header value that meilisearch must send with the processed tasks.

# 4. Technical Aspects

N/A

# 5. Future Possibilities

  • Redo the command-line to create a more interactive CLI
  • Autocomplete for the options when using the Meilisearch CLI