Fix datetime filter timezone bug

rust/perspective-viewer/src/rust/components/filter_item.rs

@@ -11,12 +11,13 @@ use crate::custom_elements::filter_dropdown::*;
 use crate::dragdrop::*;
 use crate::renderer::*;
 use crate::session::*;
+use crate::utils::{posix_to_utc_str, str_to_utc_posix};
 use crate::*;
 
 use super::containers::dragdrop_list::*;
 use super::containers::dropdown::*;
 
-use chrono::{Local, NaiveDate, NaiveDateTime, TimeZone, Utc};
+use chrono::{NaiveDate, TimeZone, Utc};
 use wasm_bindgen::JsCast;
 use web_sys::*;
 use yew::prelude::*;
@@ -82,7 +83,6 @@ impl FilterItemProperties {
                 if *x > 0_f64 {
                     Some(
                         Utc.timestamp(*x as i64 / 1000, (*x as u32 % 1000) * 1000)
-                            .with_timezone(&Local)
                             .format("%Y-%m-%d")
                             .to_string(),
                     )
@@ -92,19 +92,7 @@ impl FilterItemProperties {
             }
             (Type::Datetime, FilterTerm::Scalar(Scalar::Float(x)))
             | (Type::Datetime, FilterTerm::Scalar(Scalar::DateTime(x))) => {
-                if *x > 0_f64 {
-                    Some(
-                        Utc.timestamp(
-                            *x as i64 / 1000,
-                            ((*x as i64 % 1000) * 1000000) as u32,
-                        )
-                        .with_timezone(&Local)
-                        .format("%Y-%m-%dT%H:%M:%S%.3f")
-                        .to_string(),
-                    )
-                } else {
-                    None
-                }
+                posix_to_utc_str(*x).ok()
             }
             (Type::Bool, FilterTerm::Scalar(Scalar::Bool(x))) => {
                 Some((if *x { "true" } else { "false" }).to_owned())
@@ -209,20 +197,10 @@ impl FilterItemProperties {
                     })
                 }
                 Some(Type::Datetime) => {
-                    filter_item.2 = FilterTerm::Scalar(
-                        match NaiveDateTime::parse_from_str(
-                            &val,
-                            "%Y-%m-%dT%H:%M:%S%.3f",
-                        ) {
-                            Ok(ref posix) => Scalar::DateTime(
-                                Utc.from_local_datetime(posix)
-                                    .unwrap()
-                                    .timestamp_millis()
-                                    as f64,
-                            ),
-                            _ => Scalar::Null,
-                        },
-                    )
+                    let posix = str_to_utc_posix(&val)
+                        .map(Scalar::DateTime)
+                        .unwrap_or(Scalar::Null);
+                    filter_item.2 = FilterTerm::Scalar(posix);
                 }
                 Some(Type::Bool) => {
                     filter_item.2 = FilterTerm::Scalar(match val.as_str() {

rust/perspective-viewer/src/rust/utils/datetime.rs

@@ -0,0 +1,41 @@
+////////////////////////////////////////////////////////////////////////////////
+//
+// Copyright (c) 2018, the Perspective Authors.
+//
+// This file is part of the Perspective library, distributed under the terms
+// of the Apache License 2.0.  The full license can be found in the LICENSE
+// file.
+
+use crate::utils::*;
+
+use chrono::{DateTime, FixedOffset, NaiveDateTime, TimeZone, Utc};
+use wasm_bindgen::prelude::*;
+
+pub fn posix_to_utc_str(x: f64) -> Result<String, JsValue> {
+    let tz = FixedOffset::west(
+        js_sys::Date::new(&0.into()).get_timezone_offset() as i32 * 60,
+    );
+
+    if x > 0_f64 {
+        Ok(Utc
+            .timestamp(x as i64 / 1000, ((x as i64 % 1000) * 1000000) as u32)
+            .with_timezone(&tz)
+            .format("%Y-%m-%dT%H:%M:%S%.3f")
+            .to_string())
+    } else {
+        Err(format!("Unknown timestamp {}", x).into())
+    }
+}
+
+pub fn str_to_utc_posix(val: &str) -> Result<f64, JsValue> {
+    let tz = FixedOffset::west(
+        js_sys::Date::new(&0.into()).get_timezone_offset() as i32 * 60,
+    );
+
+    NaiveDateTime::parse_from_str(val, "%Y-%m-%dT%H:%M:%S%.3f")
+        .map(|ref posix| {
+            DateTime::<Utc>::from(tz.from_local_datetime(posix).unwrap())
+                .timestamp_millis() as f64
+        })
+        .into_jserror()
+}

rust/perspective-viewer/src/rust/utils/errors.rs

@@ -77,3 +77,9 @@ impl<T> ToJsValueError<T> for Result<T, std::io::Error> {
         self.map_err(|x: std::io::Error| JsValue::from(&format!("{}", x)))
     }
 }
+
+impl<T> ToJsValueError<T> for Result<T, chrono::ParseError> {
+    fn into_jserror(self) -> Result<T, JsValue> {
+        self.map_err(|x: chrono::ParseError| JsValue::from(&format!("{}", x)))
+    }
+}

rust/perspective-viewer/src/rust/utils/mod.rs

@@ -8,6 +8,7 @@
 
 mod async_callback;
 mod closure;
+mod datetime;
 mod debounce;
 mod errors;
 mod future_to_promise;
@@ -22,6 +23,7 @@ mod tests;
 
 pub use self::async_callback::*;
 pub use self::closure::*;
+pub use self::datetime::*;
 pub use self::debounce::*;
 pub use self::errors::*;
 pub use self::future_to_promise::*;