Expand with all currently known RPC methods

packages/types/src/ChainProperties.ts

@@ -0,0 +1,74 @@
+// Copyright 2017-2018 @polkadot/types authors & contributors
+// This software may be modified and distributed under the terms
+// of the Apache-2.0 license. See the LICENSE file for details.
+
+import { Codec } from './types';
+
+// TODO Expose known properties as they become known, currently we have `tokenSymbol` (e.g. BBQ)
+
+/**
+ * @name ChainProperties
+ * @description
+ * Wraps the properties retrieved from the chain via the `system.properties` RPC call. It extends
+ * the standard JS Map with known values exposed as a getter. While it implements a Codec, it is
+ * limited ain that it can only be used with input objects, i.e. no hex decoding.
+ * @noInheritDoc
+ */
+export default class ChainProperties extends Map<string, any> implements Codec {
+  constructor (value: { [index: string]: any } = {}) {
+    super(ChainProperties.decodeChainProperties(value));
+  }
+
+  private static decodeChainProperties (value: { [index: string]: any }): Array<[string, any]> {
+    return Object.keys(value).map((key) => ([
+      key, value[key]
+    ] as [string, any]));
+  }
+
+  /**
+   * @description Always 0, never encodes as a Uint8Array
+   */
+  get encodedLength (): number {
+    return 0;
+  }
+
+  /**
+   * @description Returns a specific names entry in the structure
+   * @param name The name of the entry to retrieve
+   */
+  get (name: string): any | undefined {
+    return super.get(name);
+  }
+
+  /**
+   * @description Unimplemented, will throw
+   */
+  toHex (): string {
+    throw new Error('Unimplemented');
+  }
+
+  /**
+   * @description Converts the Object to JSON, typically used for RPC transfers
+   */
+  toJSON (): any {
+    return [...this.keys()].reduce((json, key) => {
+      json[key] = this.get(key);
+
+      return json;
+    }, {} as any);
+  }
+
+  /**
+   * @description Returns the string representation of the value
+   */
+  toString () {
+    return JSON.stringify(this.toJSON());
+  }
+
+  /**
+   * @description Unimplemented, will throw
+   */
+  toU8a (isBare?: boolean): Uint8Array {
+    throw new Error('Unimplemented');
+  }
+}

packages/types/src/index.ts

@@ -25,6 +25,7 @@ export { default as BlockNumber } from './BlockNumber';
 // NOTE We are exporting Bool as bool to match with Rust
 export { default as bool } from './Bool';
 export { default as Bytes } from './Bytes';
+export { default as ChainProperties } from './ChainProperties';
 export { default as Data } from './Data';
 export { default as Digest } from './Digest';
 export { default as Event } from './Event';