io / proto-adapter

src/io/proto/adapter.ts bridges the protobufjs-decoded plain object to the projection module, performing Apollo PointENU (UTM metres) ↔ WGS84 (lng/lat degrees) conversions in both directions.

Exported symbols

import * as protobuf from 'protobufjs';
import type { Projection, PointXY } from './projection';

export function transformPointsInMessage(
  type: protobuf.Type,
  msg: unknown,
  transform: (p: PointXY) => PointXY,
): unknown;

export interface ApolloMapInLonLat {
  map: Record<string, unknown>;
  projString: string;
  projection: Projection;
}

export function apolloMapToLonLat(
  map: Record<string, unknown>,
  projString: string,
): Promise<ApolloMapInLonLat>;

export function apolloMapFromLonLat(
  map: Record<string, unknown>,
  projString: string,
): Promise<{ map: Record<string, unknown>; projection: Projection }>;

export function readHeaderProjString(map: Record<string, unknown>): string | null;
export function entityCounts(map: Record<string, unknown>): Record<string, number>;

Source: src/io/proto/adapter.ts:1-107.

`transformPointsInMessage(type, msg, transform)`

Recursively walks msg. When type.fullName === '.apollo.common.PointENU', the helper calls transform. Otherwise each field is resolved and recursed into; repeated fields map child by child. Returns a new tree — the input is not mutated.

`apolloMapToLonLat(map, projString)` / `apolloMapFromLonLat(map, projString)`

Convenience compositions over getMapType() + makeProjection + transformPointsInMessage. The to direction returns the projection alongside the new tree so callers can reuse it for follow-up conversions.

`readHeaderProjString(map)`

Extracts map.header.projection.proj. Tolerates string, Uint8Array, and number[] encodings; returns null for anything else. The worker uses null to trigger NEEDS_PROJECTION.

`entityCounts(map)`

function entityCounts(map: Record<string, unknown>): Record<string, number> {
  const out: Record<string, number> = {};
  for (const [key, value] of Object.entries(map)) {
    if (Array.isArray(value)) out[key] = value.length;
  }
  return out;
}

Reports the length of every top-level repeated field — the source of ApolloMapImportInfo.counts.

Relationship to entityBridge

adapter only does coordinate transforms on the raw plain object; typed entities are the next step (entityBridge/map.ts: apolloMapToEntities). Splitting the two lets the worker cache the raw lon/lat tree for lossless round-trip exports while still serving an entity-typed view to the editor.

Contributors

kent

Changelog

Last edited 4 minutes ago

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io / proto-adapter ​

Exported symbols ​

transformPointsInMessage(type, msg, transform) ​

apolloMapToLonLat(map, projString) / apolloMapFromLonLat(map, projString) ​

readHeaderProjString(map) ​

entityCounts(map) ​

Relationship to entityBridge ​

See also ​