Struct polars::prelude::JsonWriter
source · pub struct JsonWriter<W>where
W: Write,{ /* private fields */ }Available on crate feature
polars-io only.Expand description
Writes a DataFrame to JSON.
Under the hood, this uses arrow2::io::json.
arrow2 generally serializes types that are not JSON primitives, such as Date and DateTime, as their
Display-formatted versions. For instance, a (naive) DateTime column is formatted as the String "yyyy-mm-dd HH:MM:SS". To control how non-primitive columns are serialized, convert them to String or another primitive type
before serializing.
Implementations§
source§impl<W> JsonWriter<W>where
W: Write,
impl<W> JsonWriter<W>where
W: Write,
pub fn with_json_format(self, format: JsonFormat) -> JsonWriter<W>
Trait Implementations§
source§impl<W> SerWriter<W> for JsonWriter<W>where
W: Write,
impl<W> SerWriter<W> for JsonWriter<W>where
W: Write,
source§fn new(buffer: W) -> JsonWriter<W>
fn new(buffer: W) -> JsonWriter<W>
Create a new JsonWriter writing to buffer with format JsonFormat::JsonLines. To specify a different
format, use e.g., JsonWriter::new(buffer).with_json_format(JsonFormat::Json).
fn finish(&mut self, df: &mut DataFrame) -> Result<(), PolarsError>
Auto Trait Implementations§
impl<W> Freeze for JsonWriter<W>where
W: Freeze,
impl<W> RefUnwindSafe for JsonWriter<W>where
W: RefUnwindSafe,
impl<W> Send for JsonWriter<W>where
W: Send,
impl<W> Sync for JsonWriter<W>where
W: Sync,
impl<W> Unpin for JsonWriter<W>where
W: Unpin,
impl<W> UnwindSafe for JsonWriter<W>where
W: UnwindSafe,
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
source§impl<T> IntoEither for T
impl<T> IntoEither for T
source§fn into_either(self, into_left: bool) -> Either<Self, Self> ⓘ
fn into_either(self, into_left: bool) -> Either<Self, Self> ⓘ
Converts
self into a Left variant of Either<Self, Self>
if into_left is true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read moresource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self> ⓘ
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self> ⓘ
Converts
self into a Left variant of Either<Self, Self>
if into_left(&self) returns true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read more