JohnAmican

WITH q AS (
    SELECT id,
        root_id,
        version,
        lag(version) OVER (PARTITION BY root_id ORDER BY root_id, version) as prev_version,
        lead(version) OVER (PARTITION BY root_id ORDER BY root_id, version) as next_version,
        latest
    FROM trades
    ORDER BY root_id, version
)

JohnAmican

UPDATE trades SET latest = false where root_id = 'foo' AND version = 5; -- Client 1
UPDATE trades SET latest = false where root_id = 'foo' AND version = 5; -- Client 2
INSERT INTO trades (latest, root_id, version) VALUES (true, 'foo', 6); -- Client 1
INSERT INTO trades (latest, root_id, version) VALUES (true, 'foo', 6); -- Client 2, UNIQUENESS CONSTRAINT ERROR!

JohnAmican

BEGIN;
UPDATE trades SET latest = false where root_id = 'foo' AND version = 5;
INSERT INTO trades (latest, root_id, version) VALUES (true, 'foo', 6);
COMMIT;

JohnAmican

CREATE TABLE trades
(
    id      SERIAL  NOT NULL CONSTRAINT trades_pkey PRIMARY KEY,
    latest  BOOLEAN NOT NULL,
    root_id TEXT    NOT NULL,
    version INTEGER NOT NULL,
    price   INT
);

JohnAmican

CREATE UNIQUE INDEX trades_root_id_and_version ON trades (root_id, version);

JohnAmican

React = require 'react'
app = require './app'

module.exports = (data) -> React.renderToString app(data)

JohnAmican

module React
  module Server
    module Rendering
      extend ActiveSupport::Concern
      include ::BeforeRender

      included do
        before_render :set_rendered

        attr_reader :rendered

JohnAmican

bundle 'server.js',
    entries: ["your/entry/file.cjsx"]
    extensions: ['.coffee', '.cjsx']
    builtins: false # already in node
    commondir: false # already in node
    detectGlobals: false # already in node
    browserField: false # already in node
    standalone: 'render'

JohnAmican

gulp.task 'frontend-js', ->
  bundle 'application.js',
    entries: ["your/entry/file.cjsx"] # or `.coffee` or whatever
    extensions: ['.coffee', '.cjsx']
    debug: true

JohnAmican

bundle = (name, opts) ->
  _.extend opts,
    fullPaths: true
    cache: {}
    packageCache: {}

  b = browserify opts

  rebundle = ->
    b.bundle()