json-rules-engine

Installation

Add this package to Cargo.toml of your project. (Check https://crates.io/crates/json-rules-engine for right version)

toml [dependencies] json-rules-engine = { version = "0.7.0", features = ["email"] } tokio = { version = "0.3.3", features = ["macros"] } serde_json = { version = "*" } anyhow = { version = "*" }

Features

• Built in operators
• Full support for ALL, ANY, AtLeast boolean operators, including recursive nesting
• Type Safe
• Load rules from json
• HTTP post to callback url
• Built in Moustache render
• Email notifications based on SendGrid
• Safe script
• Custom function

Get started

```rust use jsonrulesengine::{Engine, Rule, Map, fromdynamic}; use serdejson::json; use serde::{Serialize, Deserialize};

[derive(Deserialize, Serialize)]

struct Facts { name: String, age: u8, action: String }

fn agegreaterthan20lessthaninclusive25(p: Map) -> bool { let facts: Facts = fromdynamic(&p.into()).unwrap(); facts.age > 20 && facts.age <= 25 }

[tokio::main]

async main() -> anyhow::Result<()> { let sendgridapikey = "kjsldkjslkjlwkjkjew";

let rule_json = json!({
    "conditions": {
        "and": [
            {
                "field": "name",
                "operator": "string_equals",
                "value": "Cheng JIANG"
            },
            {
                "field": "age",
                "operator": "int_in_range",
                "value": [20, 25] 
            },
            {
                "script": "facts.age > 20 && facts.age <= 25",
            },
            {
                "script": "my_function(facts)",
            },
            {
                "field": "action",
                "operator": "string_equals",
                "value": "coding in rust"
            }
        ]
    },
    "events": [
        {
            "type": "post_to_callback_url",
            "params": {
                "callback_url": "http://example.com/people/conding_in_rust",
                "type": "info",
                "title": "Another person is coding in rust",
                "message": "Name: {{ name }}, Age: {{ age }}, Action: {{ action }},"
            }
        },
        {
            "type": "email_notification",
            "params": {
                "from": "alex_cj96@foxmail.com",
                "to": ["abc.def@gmail.com"],
                "type": "info",
                "title": "Another person is coding in rust",
                "message": "Name: {{ name }}, Age: {{ age }}, Action: {{ action }},"
            }
        }
    ]
});

let rule: Rule = serde_json::from_str::<Rule>(&serde_json::to_string(&rule_json).unwrap()).unwrap();

let mut engine = Engine::new(sendgrid_api_key);
engine.add_rule(rule);
engine.add_function("my_function", age_greater_than20_less_than_inclusive25);

let facts = json!({
    "name": "Cheng JIANG",
    "age": 24,
    "action": "coding in rust",
});

let rule_results = engine.run(&facts).await?;

println!("{:?}", rule_results);

} ```

Special Thanks

• bsundsrud for its basic implementation ruuls-rs