@whi/entity-architect

Entity Architect (for Holochain)

A Javascript library for deconstructing DNA responses according to the Entity specification.

Overview

This module is intended to help transform DNA responses and reduce data clutter. It is designed to integrate directly after a zome call and seamlessly restructure the contents to more GUI friendly formats.

This is achieved by using Object.definePropterty to hide tracking values such as Entry/Header hashes. It keeps the contextual information available, but out of the way.

Features

• Modular architecture definitions for supporting multi-DNA GUIs
• Automatically wrap an Entity's HoloHash properties using @whi/holo-hash
• Transform Entity contents based on the type model
• Detailed error classes for unexpected input

Install

npm i @whi/entity-architect

Basic usage

const { Architecture, EntityType } = require('@whi/entity-architect');

const SomeType = new EntityType("some_type");

// Catch-all symbol "*"
SomeType.model("*", content => {
    content.published_at = new Date( content.published_at );
    content.last_updated = new Date( content.last_updated );

    return content;
});

// This will run after the catch-all callback
SomeType.model("some_model", content => {
    content.author = new AgentPubKey(content.author);

    return content;
});


const schema = new Architecture([ SomeType ]);

schema.deconstruct( "entity", {
    "id": Uint8Array [
        132,  33,  36,  18, 241, 108, 143,  79,
         16, 118, 216,  34,  80,  48, 101,  18,
         28,  37, 113, 110, 101, 177, 250, 131,
        226, 242, 145, 113, 161, 136, 138, 180,
        129, 199,  69, 165, 236, 197,  95
    ],
    "header": Uint8Array [
        132,  41,  36, 159, 249,   8, 161, 177,
        222, 245, 155, 120, 125, 232, 123, 231,
         92,  30, 242,  96, 198, 200, 155, 129,
         93,  30, 116,  95, 146, 193, 170, 215,
         18, 184,  98, 218, 148, 128,  90
    ],
    "address": Uint8Array [
        132,  33,  36,  83, 188, 220,  51, 147,
         69,  25, 114,  37, 141,  33, 227,  37,
         45, 230, 147, 173, 133, 125,  84, 105,
        158,  38,  80, 150,  14, 159, 247, 108,
        214,  30,  67, 153, 165, 189, 179
    ],
    "type": {
        "name": "some_type",
        "model": "some_model",
    },
    "content": {
        "published_at": 1624661323383,
        "last_updated": 1624661325451,
        "author": Uint8Array [
            132,  32,  36, 161, 194,  74, 117,  57,  82,
            145,   1,  85, 154,  51, 214, 254,  80,  63,
              3, 153,  46, 176, 211, 142,  68, 250, 197,
             96, 154, 147, 243,  93, 248,  61, 168,  56,
            229,  88, 223
        ],
    }
});
// {
//     [$id]: EntryHash("uhCEkEvFsj08QdtgiUDBlEhwlcW5lsfqD4vKRcaGIirSBx0Wl7MVf"),
//     [$header]: HeaderHash("uhCkkn_kIobHe9Zt4feh751we8mDGyJuBXR50X5LBqtcSuGLalIBa"),
//     [$address]: EntryHash("uhCEkU7zcM5NFGXIljSHjJS3mk62FfVRpniZQlg6f92zWHkOZpb2z"),
//     [$type]: { "name": "some_type", "model": "some_model" },
//
//     "published_at": Date(1624661325451),
//     "last_updated": Date(1624661325451),
//     "author": AgentPubKey("uhCAkocJKdTlSkQFVmjPW_lA_A5kusNOORPrFYJqT8134Pag45Vjf"),
// }

API Reference

See docs/API.md

Contributing

See CONTRIBUTING.md