base on ⚙️ Layered configuration system for Rust applications (with strong support for 12-factor applications). # config-rs > Layered configuration system for Rust applications (with strong support for [12-factor] applications). [](https://docs.rs/config)  [](https://crates.io/crates/config) [12-factor]: https://12factor.net/config - Set defaults - Set explicit values (to programmatically override) - Read from [JSON], [TOML], [YAML], [INI], [RON], [JSON5], [CORN] files - Read from environment - Loosely typed — Configuration values may be read in any supported type, as long as there exists a reasonable conversion - Access nested fields using a formatted path — Uses a subset of JSONPath; currently supports the child ( `redis.port` ) and subscript operators ( `databases[0].name` ) [JSON]: https://github.com/serde-rs/json [TOML]: https://github.com/toml-lang/toml [YAML]: https://github.com/Ethiraric/yaml-rust2 [INI]: https://github.com/zonyitoo/rust-ini [RON]: https://github.com/ron-rs/ron [JSON5]: https://github.com/callum-oakley/json5-rs [CORN]: https://cornlang.dev/ Please note that this library can not be used to write changed configuration values back to the configuration file(s)! ## Usage ### Feature flags - `ini` - Adds support for reading INI files - `json` - Adds support for reading JSON files - `yaml` - Adds support for reading YAML files - `toml` - Adds support for reading TOML files - `ron` - Adds support for reading RON files - `json5` - Adds support for reading JSON5 files - `corn` - Adds support for reading Corn files ### Support for custom formats Library provides out of the box support for most renowned data formats such as JSON or Yaml. Nonetheless, it contains an extensibility point - a `Format` trait that, once implemented, allows seamless integration with library's APIs using custom, less popular or proprietary data formats. See [custom_file_format](https://github.com/rust-cli/config-rs/tree/main/examples/custom_file_format) example for more information. ### More See the [documentation](https://docs.rs/config) or [examples](https://github.com/rust-cli/config-rs/tree/main/examples) for more usage information. ## License Licensed under either of * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or <https://www.apache.org/licenses/LICENSE-2.0>) * MIT license ([LICENSE-MIT](LICENSE-MIT) or <https://opensource.org/license/mit>) at your option. ", Assign "at most 3 tags" to the expected json: {"id":"12351","tags":[]} "only from the tags list I provide: [{"id":77,"name":"3d"},{"id":89,"name":"agent"},{"id":17,"name":"ai"},{"id":54,"name":"algorithm"},{"id":24,"name":"api"},{"id":44,"name":"authentication"},{"id":3,"name":"aws"},{"id":27,"name":"backend"},{"id":60,"name":"benchmark"},{"id":72,"name":"best-practices"},{"id":39,"name":"bitcoin"},{"id":37,"name":"blockchain"},{"id":1,"name":"blog"},{"id":45,"name":"bundler"},{"id":58,"name":"cache"},{"id":21,"name":"chat"},{"id":49,"name":"cicd"},{"id":4,"name":"cli"},{"id":64,"name":"cloud-native"},{"id":48,"name":"cms"},{"id":61,"name":"compiler"},{"id":68,"name":"containerization"},{"id":92,"name":"crm"},{"id":34,"name":"data"},{"id":47,"name":"database"},{"id":8,"name":"declarative-gui "},{"id":9,"name":"deploy-tool"},{"id":53,"name":"desktop-app"},{"id":6,"name":"dev-exp-lib"},{"id":59,"name":"dev-tool"},{"id":13,"name":"ecommerce"},{"id":26,"name":"editor"},{"id":66,"name":"emulator"},{"id":62,"name":"filesystem"},{"id":80,"name":"finance"},{"id":15,"name":"firmware"},{"id":73,"name":"for-fun"},{"id":2,"name":"framework"},{"id":11,"name":"frontend"},{"id":22,"name":"game"},{"id":81,"name":"game-engine "},{"id":23,"name":"graphql"},{"id":84,"name":"gui"},{"id":91,"name":"http"},{"id":5,"name":"http-client"},{"id":51,"name":"iac"},{"id":30,"name":"ide"},{"id":78,"name":"iot"},{"id":40,"name":"json"},{"id":83,"name":"julian"},{"id":38,"name":"k8s"},{"id":31,"name":"language"},{"id":10,"name":"learning-resource"},{"id":33,"name":"lib"},{"id":41,"name":"linter"},{"id":28,"name":"lms"},{"id":16,"name":"logging"},{"id":76,"name":"low-code"},{"id":90,"name":"message-queue"},{"id":42,"name":"mobile-app"},{"id":18,"name":"monitoring"},{"id":36,"name":"networking"},{"id":7,"name":"node-version"},{"id":55,"name":"nosql"},{"id":57,"name":"observability"},{"id":46,"name":"orm"},{"id":52,"name":"os"},{"id":14,"name":"parser"},{"id":74,"name":"react"},{"id":82,"name":"real-time"},{"id":56,"name":"robot"},{"id":65,"name":"runtime"},{"id":32,"name":"sdk"},{"id":71,"name":"search"},{"id":63,"name":"secrets"},{"id":25,"name":"security"},{"id":85,"name":"server"},{"id":86,"name":"serverless"},{"id":70,"name":"storage"},{"id":75,"name":"system-design"},{"id":79,"name":"terminal"},{"id":29,"name":"testing"},{"id":12,"name":"ui"},{"id":50,"name":"ux"},{"id":88,"name":"video"},{"id":20,"name":"web-app"},{"id":35,"name":"web-server"},{"id":43,"name":"webassembly"},{"id":69,"name":"workflow"},{"id":87,"name":"yaml"}]" returns me the "expected json"