Support null in JSON

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ag"
-version = "0.1.0"
+version = "0.3.2"
 authors = ["Russell Cohen <[email protected]>"]
 
 [dependencies]

src/data.rs

@@ -32,6 +32,7 @@ pub enum Value {
     // Consider big int
     Int(i64),
     Float(f64),
+    None,
 }
 
 impl OrdSubset for Value {
@@ -49,6 +50,7 @@ impl Display for Value {
             &Value::Str(ref s) => write!(f, "{}", s),
             &Value::Int(ref s) => write!(f, "{}", s),
             &Value::Float(ref s) => write!(f, "{}", s),
+            &Value::None => write!(f, "$None$"),
         }
     }
 }
@@ -58,14 +60,11 @@ impl Value {
         match self {
             &Value::Str(ref s) => format!("{}", s),
             &Value::Int(ref s) => format!("{}", s),
+            &Value::None => format!("$None$"),
             &Value::Float(ref s) => format!("{:.*}", render_config.floating_points, s),
         }
     }
 
-    pub fn no_value() -> Value {
-        Value::Str("$None$".to_string())
-    }
-
     pub fn from_string(s: &str) -> Value {
         let int_value = s.parse::<i64>();
         let float_value = s.parse::<f64>();

src/operator.rs

@@ -173,7 +173,7 @@ impl AggregateFunction for Percentile {
         let pct_opt = self.ckms.query(self.percentile);
         pct_opt
             .map(|(_usize, pct_float)| data::Value::Float(pct_float))
-            .unwrap_or(data::Value::no_value())
+            .unwrap_or(data::Value::None)
     }
 }
 
@@ -298,6 +298,7 @@ impl UnaryPreAggOperator for ParseJson {
                                 &&Value::String(ref s) => {
                                     Some(record.put(k, data::Value::Str(s.to_string())))
                                 }
+                                &&Value::Null => Some(record.put(k, data::Value::None)),
                                 _other => None,
                             })
                         })
@@ -320,15 +321,16 @@ mod tests {
 
     #[test]
     fn test_json() {
-        let rec = Record::new(r#"{"k1": 5, "k2": 5.5, "k3": "str"}"#);
+        let rec = Record::new(r#"{"k1": 5, "k2": 5.5, "k3": "str", "k4": null}"#);
         let parser = ParseJson {};
         let rec = parser.process(&rec).unwrap();
         assert_eq!(
             rec.data,
             hashmap!{
                 "k1".to_string() => Value::Int(5),
                 "k2".to_string() => Value::Float(5.5),
-                "k3".to_string() => Value::Str("str".to_string())
+                "k3".to_string() => Value::Str("str".to_string()),
+                "k4".to_string() => Value::None
             }
         );
     }

src/render.rs

@@ -100,9 +100,13 @@ impl PrettyPrinter {
             .iter()
             .map(|column_name| {
                 let value = record.data.get(column_name);
-                let or_none = data::Value::no_value();
-                let value = value.unwrap_or(&or_none);
-                let unpadded = format!("[{}={}]", column_name, value.render(&self.render_config));
+
+                let unpadded = match value {
+                    Some(value) => {
+                        format!("[{}={}]", column_name, value.render(&self.render_config))
+                    }
+                    None => "".to_string(),
+                };
                 if no_padding {
                     unpadded
                 } else {

test_files/test_json.log

@@ -2,3 +2,4 @@
 {"level": "error", "message": "Oh now an error!"}
 {"level": "info", "message": "A thing happened", "num_things": 12}
 {"level": "info", "message": "A different event", "event_duration": 1002.5}
+{"level": null}