IMS-backend

Backend services for the GT Inventory Management System.

Release Notes

Features

• Back end database support for creating and editing attributes
• Back end database support for creating and editing equipment types
• Back end database support for creating and editing equipment
• Back end database support for simple text search across instances
• Back end database support for soft deletion of equipment, equipment types, and attributes
• Web-facing API that can be used to perform all back end functions

Future Implementation

• Versioning

Installation Guide

Requirements: NodeJS, PostgreSQL server and database

Tested with: Node v8.9.4, PostgreSQL v10.3.

Running the web server

1. Clone this repository.
2. Run npm install to install dependencies.
3. Set the DATABASE_URL environment variable to a PostgreSQL connection URL. The tables will be created automatically if they don't already exist.
4. Run npm start to start the server.

Now the server should be running. By default, it listens on all interfaces using port 8080. The port can be configured through the PORT environment variable.

Developing

To install the dependencies, run

npm install -g typescript
npm install

Now you should be able to run tsc -w to regenerate the JS files in build/. The .ts files are transpiled to JavaScript in build/.

Use npm start to start running build/index.js.

Use npm run-script watch to get TypeScript to transpile your .ts files automatically when they change. You'll need to transpile your TypeScript to the JavaScript every time you make a change.

Note: the backend expects a PostgreSQL database connection URL to be present in the DATABASE_URL environment variable in order to establish a connection.

Using the API

The test API is available at https://ims-backend.mybluemix.net/. All requests are JSON-based.

The API requests are fully documented at https://documenter.getpostman.com/view/3796309/ims-backend/RVg2B95p.

Data Types

These are the data types contained in the backend's database

Attribute

An Attribute represents a single type of metadata that can be attached to a Type. For example, a user might want to create a “MAC Address” Attribute to attach to the “Laptop” and “Router” Types.

Key	Type	Description
id	int	Unique numerical identifier for this Attribute.
name	string	2-32 characters uniquely identifying this Attribute.
type	string	One of ('Boolean','Currency','Integer','DateTime','String','Enum','Image','TextBox'). Identifies the type of data that users may enter into this Attribute. Note: In data transfer, this is represented as a string for ease of parsing. However, in the database, it is stored as a Postgres enum type.
regex	string	A JS-compatible regex string to validate new instances of this Attribute. Only applies to Attributes of String or TextBox type.
choices	string[]	A list of possible values this Attribute may have. Only applies to Attributes of Enum type.
uniqueGlobally	bool	Should new instances of this Attribute be unique across all instances of this Attribute?
public	bool	When this field is false, unprivileged users will not be able to see the contents of this Attribute on the frontend.
helpText	string	Optional text presented to the user which will give hints on how to fill this Attribute in.
defaultValue	string	The default value this Attribute should take. For Boolean, this may be either true or false.
deleted	bool	If true, this Attribute has been soft-deleted and is no longer available.

Type

A Type represents a category of Items described by a set of Attributes attached to the Type. For example, you could have a "Laptop" type to hold all laptops, and then a "MAC Address" attribute on that type.

Key	Type	Description
id	int	Unique numerical identifier for this Type.
name	string	2-32 characters uniquely identifying this Type.
nameAttribute	int	The id of an Attribute that will be used as the display value for Item having this Type.
deleted	bool	If true, this Type has been soft-deleted and is no longer available.

Item

An Item represents 1 unique inventory item.

Key	Type	Description
id	int	Unique numerical identifier for this Item.
typeId	int	The Type this Item belongs to.
deleted	bool	If this is true, the Item has been soft-deleted and will not be visible to the public.
attributes	AttributeInstance[]	All the current Attributes and their values belonging to this Item.

AttributeInstance

AttributeInstance relations connect singular values of Attributes to Items.

Key	Type	Description
id	int	Unique numerical identifier for this instance of an attribute.
attribute	int	The id of the Attribute that this is an instance of.
value	string	The value of this instance of an attribute.
itemId	int	The Item that this AttributeInstance belongs to.

AttributeType

AttributeType relations connect Attributes to their Types.

Key	Type	Description
typeId	int	The Type that is being linked.
attributeId	int	The Attribute that is being linked.
deleted	bool	Is this AttributeType still a usable relation?
required	string	One of ('Required', 'Suggested', 'Optional'). If it is Required, attempts to pass an empty value for this Attribute will be rejected. If it is Suggested, it will be emphasized in the UI to indicate users should enter data. If it is Optional, no special treatment is done. Note: In data transfer, this is represented as a string for ease of parsing. However, in the database, it is stored as a Postgres enum type.
uniqueForType	bool	Should new instances of this AttributeType be unique across all instances of this type? Note: If the Type's uniqueGlobally attribute is true, global uniqueness will be checked regardless of this value.