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Meteor.call(name, [arg1, arg2...], [asyncCallback]) (1) name String (2) Name of method to invoke (3) arg1, arg2... EJSON-able Object [Optional] (4) asyncCallback Function [Optional] On one hand, you can do : (via Session variable, or via ReactiveVar) var syncCall = Meteor.call("my...

Create Table mysql> CREATE TABLE account (acct_num INT, amount DECIMAL(10,2)); Query OK, 0 rows affected (0.03 sec) Create Trigger mysql> CREATE TRIGGER ins_sum BEFORE INSERT ON account -> FOR EACH ROW SET @sum = @sum + NEW.amount; Query OK, 0 rows affected (0.06 sec) The CRE...

Prefer dict.get method if you are not sure if the key is present. It allows you to return a default value if key is not found. The traditional method dict[key] would raise a KeyError exception. Rather than doing def add_student(): try: students['count'] += 1 except KeyError: ...

Create a model (lets call it User) by running: $ rails g model User which will generate the file app/models/user.rb: class User include Mongoid::Document end This is all you need to have a model (albeit nothing but an id field). Unlike ActiveRecord, there is no migration files. All the...

As per the Mongoid Documentation, there are 16 valid field types: Array BigDecimal Boolean Date DateTime Float Hash Integer BSON::ObjectId BSON::Binary Range Regexp String Symbol Time TimeWithZone To add a field (let's call it name and have it be a String), add this to your mode...

Mongoid allows Embedded Associations: One-to-one: embeds_one / embedded_in One-to-many: embeds_many / embedded_in To add an association (lets say the User embeds_many addresses), add this to your User file: embeds_many :addresses and this to your Address model file: embedded_in :user ...

Mongoid tries to have similar syntax to ActiveRecord when it can. It supports these calls (and many more) User.first #Gets first user from the database User.count #Gets the count of all users from the database User.find(params[:id]) #Returns the user with the id found in params[:id] User.w...

The first thing you need to know when structuring your apps is that the Meteor tool has some directories that are hard-coded with specific logic. At a very basic level, the following directories are "baked in" the Meteor bundler. client/ # client applicati...

Many people find themselves eventually supporting multiple applications, and desire to share code between apps. This leads to the concept of microservice architecture, and all-package apps. Essentially, the code from the entire classic directory structure is refactored out into packages. Even tho...

The most recent versions of Meteor ship with support for ecmascript, aka ES6 or ES2015. Instead of packages, Javascript now supports import statements and modules, which replaces the need for package-only applications. The latest directory structure is similar to the package-only structure, but us...

And, of course, you can mix these approaches, and use both packages and imports along side your application specific code. A mix-mode structure is most common in three situations: a franken-app, which is just sort of pulling a bit from here-and-there without any overall strategy; an app that's bei...

Deploy Meteor App to Ubuntu with Nginx Proxy How to Create an SSL Certificate on Nginx for Ubuntu 14 How to Deploy a Meteor JS App on Ubuntu with Nginx How to Install an SSL Certificate from a Commercial Certificate Authority NameCheap SSL Certificates

One of the simplest ways to control program flow is by using if selection statements. Whether a block of code is to be executed or not to be executed can be decided by this statement. The syntax for if selection statement in C could be as follows: if(cond) { statement(s); /*to be executed, o...

While if performs an action only when its condition evaluate to true, if / else allows you to specify the different actions when the condition true and when the condition is false. Example: if (a > 1) puts("a is larger than 1"); else puts("a is not larger than 1"...

MySQL does not provide a built-in way to create pivot queries. However, these can be created using prepared statements. Assume the table tbl_values: IdNameGroupValue1PeteA102PeteB203JohnA10 Request: Create a query that shows the sum of Value for each Name; the Group must be column header and Name...

1) Create a Contract Class A contract class defines constants that help applications work with the content URIs, column names, intent actions, and other features of a content provider. Contract classes are not included automatically with a provider; the provider's developer has to define them and t...

The primary way of getting input would be from injecting the Illuminate\Http\Request into your controller, after that there are numerous ways of accessing the data, 4 of which are in the example below. <?php namespace App\Http\Controllers; use Illuminate\Http\Request; class UserController...

globalize gem is a great solution to add translations to your ActiveRecord models. You can install it adding this to your Gemfile: gem 'globalize', '~> 5.0.0' If you're using Rails 5 you will also need to add activemodel-serializers-xml gem 'activemodel-serializers-xml' Model translations...

Due to type erasure the following will not work: public <T> void genericMethod() { T t = new T(); // Can not instantiate the type T. } The type T is erased. Since, at runtime, the JVM does not know what T originally was, it does not know which constructor to call. Workarounds ...

When an HTTP server receives a well-formed HTTP request, it must process the information that request contains and return a response to the client. A simple HTTP 1.1 response, may look like any of the following, usually followed by a number of header fields, and possibly a response body: HTTP/1.1 2...