apache-arrow/src/fb/schema.ts

Apache Arrow columnar in-memory format

// automatically generated by the FlatBuffers compiler, do not modify

import * as flatbuffers from 'flatbuffers';

import { Endianness } from './endianness.js';
import { Field } from './field.js';
import { KeyValue } from './key-value.js';


/**
 * ----------------------------------------------------------------------
 * A Schema describes the columns in a row batch
 */
export class Schema {
  bb: flatbuffers.ByteBuffer|null = null;
  bb_pos = 0;
  __init(i:number, bb:flatbuffers.ByteBuffer):Schema {
  this.bb_pos = i;
  this.bb = bb;
  return this;
}

static getRootAsSchema(bb:flatbuffers.ByteBuffer, obj?:Schema):Schema {
  return (obj || new Schema()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
}

static getSizePrefixedRootAsSchema(bb:flatbuffers.ByteBuffer, obj?:Schema):Schema {
  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
  return (obj || new Schema()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
}

/**
 * endianness of the buffer
 * it is Little Endian by default
 * if endianness doesn't match the underlying system then the vectors need to be converted
 */
endianness():Endianness {
  const offset = this.bb!.__offset(this.bb_pos, 4);
  return offset ? this.bb!.readInt16(this.bb_pos + offset) : Endianness.Little;
}

fields(index: number, obj?:Field):Field|null {
  const offset = this.bb!.__offset(this.bb_pos, 6);
  return offset ? (obj || new Field()).__init(this.bb!.__indirect(this.bb!.__vector(this.bb_pos + offset) + index * 4), this.bb!) : null;
}

fieldsLength():number {
  const offset = this.bb!.__offset(this.bb_pos, 6);
  return offset ? this.bb!.__vector_len(this.bb_pos + offset) : 0;
}

customMetadata(index: number, obj?:KeyValue):KeyValue|null {
  const offset = this.bb!.__offset(this.bb_pos, 8);
  return offset ? (obj || new KeyValue()).__init(this.bb!.__indirect(this.bb!.__vector(this.bb_pos + offset) + index * 4), this.bb!) : null;
}

customMetadataLength():number {
  const offset = this.bb!.__offset(this.bb_pos, 8);
  return offset ? this.bb!.__vector_len(this.bb_pos + offset) : 0;
}

/**
 * Features used in the stream/file.
 */
features(index: number):bigint|null {
  const offset = this.bb!.__offset(this.bb_pos, 10);
  return offset ? this.bb!.readInt64(this.bb!.__vector(this.bb_pos + offset) + index * 8) : BigInt(0);
}

featuresLength():number {
  const offset = this.bb!.__offset(this.bb_pos, 10);
  return offset ? this.bb!.__vector_len(this.bb_pos + offset) : 0;
}

static startSchema(builder:flatbuffers.Builder) {
  builder.startObject(4);
}

static addEndianness(builder:flatbuffers.Builder, endianness:Endianness) {
  builder.addFieldInt16(0, endianness, Endianness.Little);
}

static addFields(builder:flatbuffers.Builder, fieldsOffset:flatbuffers.Offset) {
  builder.addFieldOffset(1, fieldsOffset, 0);
}

static createFieldsVector(builder:flatbuffers.Builder, data:flatbuffers.Offset[]):flatbuffers.Offset {
  builder.startVector(4, data.length, 4);
  for (let i = data.length - 1; i >= 0; i--) {
    builder.addOffset(data[i]!);
  }
  return builder.endVector();
}

static startFieldsVector(builder:flatbuffers.Builder, numElems:number) {
  builder.startVector(4, numElems, 4);
}

static addCustomMetadata(builder:flatbuffers.Builder, customMetadataOffset:flatbuffers.Offset) {
  builder.addFieldOffset(2, customMetadataOffset, 0);
}

static createCustomMetadataVector(builder:flatbuffers.Builder, data:flatbuffers.Offset[]):flatbuffers.Offset {
  builder.startVector(4, data.length, 4);
  for (let i = data.length - 1; i >= 0; i--) {
    builder.addOffset(data[i]!);
  }
  return builder.endVector();
}

static startCustomMetadataVector(builder:flatbuffers.Builder, numElems:number) {
  builder.startVector(4, numElems, 4);
}

static addFeatures(builder:flatbuffers.Builder, featuresOffset:flatbuffers.Offset) {
  builder.addFieldOffset(3, featuresOffset, 0);
}

static createFeaturesVector(builder:flatbuffers.Builder, data:bigint[]):flatbuffers.Offset {
  builder.startVector(8, data.length, 8);
  for (let i = data.length - 1; i >= 0; i--) {
    builder.addInt64(data[i]!);
  }
  return builder.endVector();
}

static startFeaturesVector(builder:flatbuffers.Builder, numElems:number) {
  builder.startVector(8, numElems, 8);
}

static endSchema(builder:flatbuffers.Builder):flatbuffers.Offset {
  const offset = builder.endObject();
  return offset;
}

static finishSchemaBuffer(builder:flatbuffers.Builder, offset:flatbuffers.Offset) {
  builder.finish(offset);
}

static finishSizePrefixedSchemaBuffer(builder:flatbuffers.Builder, offset:flatbuffers.Offset) {
  builder.finish(offset, undefined, true);
}

static createSchema(builder:flatbuffers.Builder, endianness:Endianness, fieldsOffset:flatbuffers.Offset, customMetadataOffset:flatbuffers.Offset, featuresOffset:flatbuffers.Offset):flatbuffers.Offset {
  Schema.startSchema(builder);
  Schema.addEndianness(builder, endianness);
  Schema.addFields(builder, fieldsOffset);
  Schema.addCustomMetadata(builder, customMetadataOffset);
  Schema.addFeatures(builder, featuresOffset);
  return Schema.endSchema(builder);
}
}