@polkadot/types#decorateStorage TypeScript Examples

The following examples show how to use @polkadot/types#decorateStorage. You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.
Example #1
Source File: base-provider.ts    From bodhi.js with Apache License 2.0 5 votes vote down vote up 
queryStorage = async <T = any>(
    module: `${string}.${string}`,
    args: any[],
    _blockTag?: BlockTag | Promise<BlockTag>
  ): Promise<T> => {
    const blockTag = await this._ensureSafeModeBlockTagFinalization(_blockTag);
    const blockHash = await this._getBlockHash(blockTag);

    const registry = await this.api.getBlockRegistry(u8aToU8a(blockHash));

    if (!this.storages.get(registry)) {
      const storage = decorateStorage(registry.registry, registry.metadata.asLatest, registry.metadata.version);
      this.storages.set(registry, storage);
    }

    const storage = this.storages.get(registry)!;

    const [section, method] = module.split('.');

    const entry = storage[section][method];
    const key = entry(...args);

    const outputType = unwrapStorageType(registry.registry, entry.meta.type, entry.meta.modifier.isOptional);

    const cacheKey = `${module}-${blockHash}-${args.join(',')}`;
    const cached = this._storageCache.get(cacheKey);

    let input: Uint8Array | null = null;

    if (cached) {
      input = cached;
    } else {
      const value: any = await this.api.rpc.state.getStorage(key, blockHash);

      const isEmpty = isNull(value);

      // we convert to Uint8Array since it maps to the raw encoding, all
      // data will be correctly encoded (incl. numbers, excl. :code)
      input = isEmpty
        ? null
        : u8aToU8a(entry.meta.modifier.isOptional ? value.toU8a() : value.isSome ? value.unwrap().toU8a() : null);

      this._storageCache.set(cacheKey, input);
    }

    const result = registry.registry.createTypeUnsafe(outputType, [input], {
      blockHash,
      isPedantic: !entry.meta.modifier.isOptional
    });

    return result as any as T;
  };