Method build_decoder

arrow-json/src/reader/mod.rs:326–353

Create a [`Decoder`]

(self)

    /// Create a [`Decoder`]
    pub fn build_decoder(self) -> Result<Decoder, ArrowError> {
        let (data_type, nullable) = if self.is_field {
            let field = &self.schema.fields[0];
            let data_type = Cow::Borrowed(field.data_type());
            (data_type, field.is_nullable())
        } else {
            let data_type = Cow::Owned(DataType::Struct(self.schema.fields.clone()));
            (data_type, false)
        };

        let ctx = DecoderContext {
            coerce_primitive: self.coerce_primitive,
            strict_mode: self.strict_mode,
            struct_mode: self.struct_mode,
            ignore_type_conflicts: self.ignore_type_conflicts,
        };
        let decoder = ctx.make_decoder(data_type.as_ref(), nullable)?;

        let num_fields = self.schema.flattened_fields().len();

        Ok(Decoder {
            decoder,
            is_field: self.is_field,
            tape_decoder: TapeDecoder::new(self.batch_size, num_fields),
            batch_size: self.batch_size,
            schema: self.schema,
        })
    }
}

/// Reads JSON data with a known schema directly into arrow [`RecordBatch`]