feat: add casbin_js_get_permission_for_user (#339)

* feat: add casbin_js_get_permission_for_user

* fix: cargo fmt

* fix: pass test

* fix: pass test under linux

Cargo.toml

@@ -44,6 +44,7 @@ slog-term = { version = "2.9.0", optional = true }
 thiserror = "1.0.30"
 tokio = { version = "1.17.0", optional = true, default-features = false }
 tokio-stream = { version = "0.1.8", optional = true, default-features = false }
+serde_json = "1.0.127"
 
 [features]
 default = ["runtime-tokio", "incremental"]

src/frontend.rs

@@ -0,0 +1,102 @@
+use crate::{CoreApi, Enforcer};
+use std::collections::HashMap;
+
+pub fn casbin_js_get_permission_for_user(
+    e: &Enforcer,
+    _user: &str,
+) -> Result<String, Box<dyn std::error::Error>> {
+    let model = e.get_model();
+    let mut m = HashMap::new();
+
+    m.insert("m", serde_json::Value::from(model.to_text()));
+
+    let mut p_rules = Vec::new();
+    if let Some(assertions) = model.get_model().get("p") {
+        for (ptype, _assertion) in assertions {
+            let policies = model.get_policy("p", ptype);
+            for rules in policies {
+                let mut rule = vec![ptype.to_string()];
+                rule.extend(rules);
+                p_rules.push(rule);
+            }
+        }
+    }
+    m.insert("p", serde_json::Value::from(p_rules));
+
+    let mut g_rules = Vec::new();
+    if let Some(assertions) = model.get_model().get("g") {
+        for (ptype, _assertion) in assertions {
+            let policies = model.get_policy("g", ptype);
+            for rules in policies {
+                let mut rule = vec![ptype.to_string()];
+                rule.extend(rules);
+                g_rules.push(rule);
+            }
+        }
+    }
+    m.insert("g", serde_json::Value::from(g_rules));
+
+    let result = serde_json::to_string(&m)?;
+    Ok(result)
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::frontend::casbin_js_get_permission_for_user;
+    use crate::prelude::*;
+
+    #[cfg(not(target_arch = "wasm32"))]
+    #[cfg_attr(
+        all(feature = "runtime-async-std", not(target_arch = "wasm32")),
+        async_std::test
+    )]
+    #[cfg_attr(
+        all(feature = "runtime-tokio", not(target_arch = "wasm32")),
+        tokio::test
+    )]
+    async fn test_casbin_js_get_permission_for_user() {
+        use serde_json::Value;
+        use std::fs;
+        use std::io::Read;
+
+        let model_path = "examples/rbac_model.conf";
+        let policy_path = "examples/rbac_with_hierarchy_policy.csv";
+        let e = Enforcer::new(model_path, policy_path).await.unwrap();
+
+        let received_string =
+            casbin_js_get_permission_for_user(&e, "alice").unwrap();
+        let received: Value = serde_json::from_str(&received_string).unwrap();
+
+        let mut expected_model = String::new();
+        fs::File::open(model_path)
+            .unwrap()
+            .read_to_string(&mut expected_model)
+            .unwrap();
+        let expected_model_str =
+            expected_model.replace("\r\n", "\n").replace("\n\n", "\n");
+
+        assert_eq!(
+            received["m"].as_str().unwrap().trim(),
+            expected_model_str.trim()
+        );
+
+        let mut expected_policies = String::new();
+        fs::File::open(policy_path)
+            .unwrap()
+            .read_to_string(&mut expected_policies)
+            .unwrap();
+        let expected_policies_items: Vec<&str> =
+            expected_policies.split(&[',', '\n'][..]).collect();
+
+        let mut i = 0;
+        for s_arr in received["p"].as_array().unwrap() {
+            for s in s_arr.as_array().unwrap() {
+                assert_eq!(
+                    s.as_str().unwrap().trim(),
+                    expected_policies_items[i].trim()
+                );
+                i += 1;
+            }
+        }
+    }
+}

src/lib.rs

@@ -29,6 +29,7 @@ mod util;
 mod watcher;
 
 pub mod error;
+pub mod frontend;
 pub mod prelude;
 
 #[cfg(not(target_arch = "wasm32"))]

src/model/default_model.rs

@@ -384,6 +384,66 @@ impl Model for DefaultModel {
         }
         (res, rules_removed)
     }
+
+    fn to_text(&self) -> String {
+        let mut token_patterns = HashMap::new();
+        let p_pattern = regex::Regex::new(r"^p_").unwrap();
+        let r_pattern = regex::Regex::new(r"^r_").unwrap();
+
+        for ptype in ["r", "p"] {
+            if let Some(assertion) = self.model.get(ptype) {
+                for token in &assertion[ptype].tokens {
+                    let new_token = p_pattern.replace_all(token, "p.");
+                    let new_token = r_pattern.replace_all(&new_token, "r.");
+                    token_patterns.insert(token.clone(), new_token.to_string());
+                }
+            }
+        }
+
+        if let Some(assertions) = self.model.get("e") {
+            if let Some(assertion) = assertions.get("e") {
+                if assertion.value.contains("p_eft") {
+                    token_patterns
+                        .insert("p_eft".to_string(), "p.eft".to_string());
+                }
+            }
+        }
+
+        let mut s = String::new();
+
+        let write_string = |sec: &str, s: &mut String| {
+            if let Some(assertions) = self.model.get(sec) {
+                for (_ptype, assertion) in assertions {
+                    let mut value = assertion.value.clone();
+                    for (token_pattern, new_token) in &token_patterns {
+                        value = value.replace(token_pattern, new_token);
+                    }
+                    s.push_str(&format!("{} = {}\n", sec, value));
+                }
+            }
+        };
+
+        s.push_str("[request_definition]\n");
+        write_string("r", &mut s);
+        s.push_str("[policy_definition]\n");
+        write_string("p", &mut s);
+
+        if self.model.contains_key("g") {
+            s.push_str("[role_definition]\n");
+            if let Some(assertions) = self.model.get("g") {
+                for (ptype, assertion) in assertions {
+                    s.push_str(&format!("{} = {}\n", ptype, assertion.value));
+                }
+            }
+        }
+
+        s.push_str("[policy_effect]\n");
+        write_string("e", &mut s);
+        s.push_str("[matchers]\n");
+        write_string("m", &mut s);
+
+        s
+    }
 }
 
 #[cfg(test)]

src/model/mod.rs

@@ -72,4 +72,5 @@ pub trait Model: Send + Sync {
         field_index: usize,
         field_values: Vec<String>,
     ) -> (bool, Vec<Vec<String>>);
+    fn to_text(&self) -> String;
 }