Merge pull request #27 from RedisLabsModules/del_replace

Del replace

Author: gkorland

Cargo.lock

@@ -10,5 +10,5 @@ crate-type = ["cdylib"]
 [dependencies]
 serde_json = "1.0"
 libc = "0.2"
-jsonpath_lib = "0.2.0"
-redismodule = { path = "redismodule-rs", version = "0.1.0" }
+jsonpath_lib = "0.2.3"
+redismodule = { path = "redismodule-rs", version = "0.1.0" }

Cargo.toml

@@ -16,11 +16,25 @@ pub enum SetOptions {
     AlreadyExists,
 }
 
+fn json_del(ctx: &Context, args: Vec<String>) -> RedisResult {
+    let mut args = args.into_iter().skip(1);
+
+    let key = args.next_string()?;
+    let path = args.next_string()?;
+
+    let key = ctx.open_key_writable(&key);
+    let deleted = match key.get_value::<RedisJSON>(&REDIS_JSON_TYPE)? {
+        Some(doc) => doc.delete_path(&path)?,
+        None => 0
+    };
+    Ok(deleted.into())
+}
+
 fn json_set(ctx: &Context, args: Vec<String>) -> RedisResult {
     let mut args = args.into_iter().skip(1);
 
     let key = args.next_string()?;
-    let _path = args.next_string()?; // TODO handle this path
+    let path = args.next_string()?;
     let value = args.next_string()?;
 
     let set_option = args.next()
@@ -39,7 +53,7 @@ fn json_set(ctx: &Context, args: Vec<String>) -> RedisResult {
     match (current, set_option) {
         (Some(_), Some(SetOptions::NotExists)) => Ok(().into()),
         (Some(ref mut doc), _) => {
-            doc.set_value(&value)?;
+            doc.set_value(&value, &path)?;
             REDIS_OK
         }
         (None, Some(SetOptions::AlreadyExists)) => Ok(().into()),
@@ -112,8 +126,6 @@ fn json_mget(ctx: &Context, args: Vec<String>) -> RedisResult {
     } else {
         Err(RedisError::WrongArity)
     }
-
-
 }
 
 
@@ -157,6 +169,7 @@ redis_module! {
     ],
     commands: [
         ["json.set", json_set, "write"],
+        ["json.del", json_del, "write"],
         ["json.get", json_get, ""],
         ["json.mget", json_mget, ""],
         ["json.strlen", json_strlen, ""],

src/lib.rs

@@ -3,7 +3,7 @@
 // Translate between JSON and tree of Redis objects:
 // User-provided JSON is converted to a tree. This tree is stored transparently in Redis.
 // It can be operated on (e.g. INCR) and serialized back to JSON.
-
+use std::mem;
 use serde_json::Value;
 use jsonpath_lib::{JsonPathError};
 
@@ -43,28 +43,37 @@ pub struct RedisJSON {
 
 impl RedisJSON {
     pub fn from_str(data: &str) -> Result<Self, Error> {
-        eprintln!("Parsing JSON from input '{}'", data);
-
         // Parse the string of data into serde_json::Value.
         let v: Value = serde_json::from_str(data)?;
 
         Ok(Self { data: v })
     }
 
-    pub fn set_value(&mut self, data: &str) -> Result<(), Error> {
-        eprintln!("Parsing JSON from input '{}'", data);
-
+    pub fn set_value(&mut self, data: &str, path: &str) -> Result<(), Error> {
         // Parse the string of data into serde_json::Value.
-        let v: Value = serde_json::from_str(data)?;
+        let json: Value = serde_json::from_str(data)?;
 
-        self.data = v;
+        let current_data = mem::replace(&mut self.data, Value::Null);
+        let new_data = jsonpath_lib::replace_with(current_data, path, &mut |_v| {
+            json.clone()
+        })?;
+        self.data = new_data;
 
         Ok(())
     }
 
-    pub fn to_string(&self, path: &str) -> Result<String, Error> {
-        eprintln!("Serializing back to JSON");
+    pub fn delete_path(&mut self, path: &str) -> Result<usize, Error> {
+        let current_value = mem::replace(&mut self.data, Value::Null);
+        self.data = jsonpath_lib::delete(current_value, path)?;
 
+        let res : usize = match self.data {
+            Value::Null => 0,
+            _ => 1
+        };
+        Ok(res)
+    }
+
+    pub fn to_string(&self, path: &str) -> Result<String, Error> {
         let results = self.get_doc(path)?;
         Ok(serde_json::to_string(&results)?)
     }