Struct polars_io::json::JsonWriter

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pub struct JsonWriter<W: Write> { /* private fields */ }
Available on crate feature json 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.

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impl<W: Write> JsonWriter<W>

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pub fn with_json_format(self, format: JsonFormat) -> Self

Trait Implementations§

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impl<W> SerWriter<W> for JsonWriter<W>
where W: Write,

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fn new(buffer: W) -> Self

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).

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fn finish(&mut self, df: &mut DataFrame) -> PolarsResult<()>

Auto Trait Implementations§

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impl<W> Freeze for JsonWriter<W>
where W: Freeze,

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impl<W> RefUnwindSafe for JsonWriter<W>
where W: RefUnwindSafe,

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impl<W> Send for JsonWriter<W>
where W: Send,

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impl<W> Sync for JsonWriter<W>
where W: Sync,

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impl<W> Unpin for JsonWriter<W>
where W: Unpin,

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impl<W> UnwindSafe for JsonWriter<W>
where W: UnwindSafe,

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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impl<T> BorrowMut<T> for T
where T: ?Sized,

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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T> Instrument for T

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where U: From<T>,

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Calls U::from(self).

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type Output = T

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where U: Into<T>,

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where U: TryFrom<T>,

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where S: Into<Dispatch>,

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