THIS PROJECT IS CONTINUED BY VALAA TECHNOLOGIES

This repository is no longer maintained. Development is continued by Valaa Technologies. Repository can be found here.

Valaa Stack

Distributed platform of platforms, with minimal threshold of entry for creating applications with familiar HTML5/CSS/JS and then deploying, sharing and reusing not just the applications themselves, but modules and the content as well, using a unified, powerful resource model.

Community

Valaa Stack is open source software released under an MIT license.

Installation

Undergoing reorganization.

Once done, valaa-manager (valma) can be used to deploy a local web server which can serve an initial developer targeted landing page (inside a revelation). This contains the Valaa javascript client runtime (Inspire) and the main editor partition (Zero) as preloaded ValaaSpace content. While this local Zero is primarily aimed at developing in a local browser context (backed by IndexedDB) it nevertheless is fundamentally fully capable of connecting and manipulating to remote authority content when properly authenticated.

Overview

Most of the Valaa infrastructure logic lies within the sub-modules of the Inspire client javascript runtime which runs in user browsers.

Applications are created on top of this infrastructure in the form of Valaa resources, which are stored in a globally shared ValaaSpace. In order to efficiently show these applications to the user Inspire loads only small parts of the whole ValaaSpace (called partitions) inside the user's browser. It accomplishes this using event streams.

Event stream circle of life

Inspire client connects to selected partitions inside remote authorities to receive application and content event streams. It then locally interprets these events as Valaa resources which contain the structure, code, UI components and data all together making up the application. Inspire then renders these to the user as a fully locally interactive web page.

When user then interacts with the application and makes a modification which should affect other users, Inspire sends this modification to the appropriate remote authority as a command. The authority can then authorize this command as a new event as part of its event stream. When doing so the authority sends the new event to all other clients who were registered to the content, thus completing the circle.

Everything that happens or is created in ValaaSpace is created using this cycle. Zero, the primary ValaaSpace content editor, is merely another Valaa application rendered by Inspire and has indeed been primarily developed using itself (after a brief bootstrapping phase).

Backend authorities can be simple

A minimal but complete backend authority needs to be two things:

• An event sourcing pub-sub hub and event log provider; to be able authorize (or reject) incoming commands into events and then publish these to clients who are subscribed to the relevant partitions, as well as provide full event logs when requested
• An immutable binary hosting provider: to receive blob content which is referred to by above events and then later deliver the content to clients requesting it.

Backend authorities are allowed and in fact expected to be much more than this. Nevertheless, when even such minimal authorities are combined with a way to deliver the Inspire runtime to users this completes Valaa as a fully self-contained platform.

Note: tools for managing reference authority deplyoments will likely be contained in a separate repository (as valma).

Inspire components

Inspire client is divided into several sub-modules. For now they exist in the same repository but eventually might be separated. They share similarities in structure. valaa-inspire is the top level entry point. Those extending the schema provide a root-level ContentAPI.js. Several modules provide an incremental test harness under */test/*TestHarness. valaa-tools contains assorted generic tools. Some shared concepts between all the submodules:

• dev-depends: jest, eslint, flow, babel, webpack, npm
• depends: lodash, graphql, es5, various polyfills
• concepts: event sourcing, distributed infrastructure, es6

valaa-core

The execution core. Provides the ability to reduce event streams into in-memory Valaa resources and their updates. Provides schema definitions for Resource and other essential Valaa resource model interfaces. Provides a kuery language VALK for accessing and making limited manipulations to the resources. Provides the low level APIs for manipulating partitions. Implements ghost instancing for the Valaa resource model, an extension of the traditional prototypical inheritance which recursively inherits the sub-components of the prototype as transparent but selectively modifiable ghosts. Provides referential integrity to the resource model via couplings.

• depends: valaa-tools, redux, immutable
• exports: Corpus, Command, VALK, CoreContentAPI
• ValaaSpace: Resource, ResourceStub, Blob, Partition
• concepts: ghost instancing, partitions, couplings

valaa-script

Extends the core with ValaaScript. It is a semantic, non-syntactic extension of Javascript which seamlessly integrates Valaa resources with the Javascript object model. Bridges the gap between Javascript model and Valaa resource model by extensively extending the schema. Provides an implementation for ValaaScript via transpilation into an intermediate language in the form of VALK kueries.

• depends: valaa-core, acorn
• exports: transpileValaaScript, VALSK, ScriptContentAPI
• ValaaSpace: Scope, Property
• concepts: ECMAScript2015, scope, transpilation

valaa-prophet

Provides event stream connectivity. This is not just to remote authorities but also to local browser IndexedDB storage. Provides a non-authoritative in-memory repository FalseProphet, which wraps valaa-core and valaa-script. Provides command queueing and reformation capabilities. Provides a client-side ACID transaction framework with transparent ValaaScript integration. Provides blob content caching and management pathways. Extends the schema with folder-like structure as well as relation-like connectivity. Together these provide fully offline mode readiness. Provides the backend event stream connectivity reference implementation with AWS using simple REST lambdas and the AWS mqtt IoT as event pub-sub.

• depends: valaa-script, IndexedDB, AWS IoT/S3/DynamoDB
• exports: FalseProphet, PartitionConnection, ProphetContentAPI
• ValaaSpace: Relatable, Entity, Media, Relation,
• concepts: ACID, authorities, pub-sub, offline readiness

valaa-engine

Provides the live proxies (Vrappers) to ValaaSpace resources with ValaaEngine. Completes the modifcation and transaction frameworks with the ability to create commands with the proxy objects. Provides Media content interpreter framework, which allows converting ValaaScript content inside ValaaSpace into executable code. This also allows integrating existing javascript code through ValaaScript seamless integration. Converts events into subscriber callbacks calls. Together these enable fully live-updating ValaaScript code via VALK kueries as intermediate language. Exposes ValaaScript standard API into ValaaSpace as Valaa execution environment global scope primitive, with which ValaaScript programs have full control over computation, stream connectivity and rendering environment inside the browser.

• depends: valaa-prophet
• exports: ValaaEngine, Vrapper, VALEK
• ValaaSpace: Valaa.*, Object integration
• concepts: live kuery, code-as-content, 3rd party libraries

valaa-inspire

Provides the runtime entry point and UI rendering integration using React. Sets up the full ValaaStack. Manages initial authentication and connects to the entry partition. Sets up the rendering module, attaches it to DOM and renders the entry partition LENS. Renders resources using attached lens Media files. Introduces a Media type VSX (similar to JSX) specifically for this purpose, which allows writing natural HTML but also embedding it with fully live ValaaScript snippets. With promise-enabled rendering enables fully dynamic ValaaSpace integration with the UI.

• depends: valaa-engine, React, brace
• exports: createInspireClient,
• ValaaSpace: ValaaScope, If, ForEach, TextFileEditor
• concepts: model-view, HTML5/CSS/JS, rapid devevelopment

The promise and the claim

Client-side computation, fully self-referential unified resource model, fundamentally live UI, full library integrations together with scalable distributed event sourcing based infrastructure enables uncompromising, no barrier of entry back-to-the-HTML5/CSS/JS-roots hyper-rapid but still genuinely sustainable software development.

Let's see if this is true. _o/