Per Service Schemas

Overview

Each service manages a schema of object/resources that it is responsible for, this schema is available to other services and frontends. The schema includes a list of fields available for each object.

File Structure

• see Repository structure

Example Per Service ObjectTypes.js

• stored in top level schemas folder

[
	"xxx",
	"yyy",
	 // ...
]

Example ObjectSchema

{
	objectType: "xx",
	canDelete: false, // whether any fields can be deleted // default = false
	overWriteHandlers: { // optional, if not set will create default handlers
		create: [], // default: ['hdrApi', 'hdrSqs']
		update: [], // default: ['hdrApi', 'hdrSqs']
		get: [], // default: ['hdrApi', 'hdrInv']
		delete: [], // default: ['hdrApi', 'hdrSqs']
	},
	addOnDataStructure: [ // optional, add for additional setting to objectType
		{
			type:"versionedData",
			versionedDataLabel: "xx", // versionedData label name
			storageResourceTag : "xx", // ref to storegeResourceTag
			fieldNames: [
				{
					fieldName: "xx",
					type: "xx", // string|integer|currency|float|special| 
					requireOnCreate: false, // default = false
					optionalOnCreate: false, // default = false,
					canUpdate: true, // default = true
					validation: {} 
				},
				// ...
			]
        },
		// ...
	],
	overwriteGeneratedMainFunction: ["create", "..."], // list of actions that will use user created Main Lambda instead of generated main Lamnbda
	storageResources:{
		"xxx":{ // storageResourceTag
			storageType: "xx", // dynamoDB | graph
		
			// setting for storageType dynamoDB
			tableName: "xx",
			groupByPartitionKeyField: "xx", // use this fieldName as partitionKey instead of use partitionKey in identifiers

			// setting for storageType graph
			graphServerTag: "xx",
		}
	},
	fieldNames: {
		xxx: { // fieldName
			type: "xx", // string|integer|currency|float|special|..
			requiredOnCreate: false, // default = false
			optionalOnCreate: false, // default = false
			canUpdate: true, // default = true
			validation: {}, // maybe ajv syntax
			storageResourceTags: ["xx","yy"], // reference to storageResources property
			versionedDataLabel: "xx", //  name of versionedDataLabel to store data
			fromServiceNameTag: "xxx" , // service responsible for object schema
			fromObjectType: "xxx" , // objectType at fromServiceNameTag
		},
		// ...
	},
	calculatedFields: {
		xxx: { // fieldName
			type: "xx", // string|integer|currency|float|special|..
			// required requestParams?
		},
		// ...
	}
    compositeKeyDeliminator: "xx", // join partitionKey and sortKey
	identifiers: [
	{
		type: "partitionKey",

		fieldNames: ["xx","yy"], // composite partition keys in DynamoDB
		deliminator: "xx",  // optional, defaults to "_"
		name: "zz", // name of field in database
		// or
		fieldName: "xx"
	
	},
	{
		type: "sortKey",

		fieldNames: ["xx","yy"], // composite partition keys in DynamoDB
		deliminator: "xx",  // optional, defaults to "_"
		name: "zz", // name of field in database
		// or
		fieldName: "xx"
	
	},
  ]
},
{
	// for objects stored in graph this will add another node label
	objectType: "xx", // new label to add
	extendObjType: { // core object that this object extends
		serviceTag: "xxx",
		objectType: "xxx",
	},
	// actions can be peformed on the extended object, which will handle the core fields + any extended fields
	overWriteHandlers: { // optional, if not set will create default handlers
		// (see above)
	}
	overwriteGeneratedMainFunction: ["create", "..."], // list of actions that will use user created Main Lambda instead of generated main Lamnbda
	storageResources:{ // these are the storageResources that carry the extended objects settings, 
		// (see above)
	},
	fieldNames: {
		// (see above)
	},
	calculatedFields: {
		// (see above)
	}
	// canDelete/identifiers come from the core object
}

Example Relationships Schema

• stored in top level schemas folder
• parent/child determines relationship direction for graph relationships
• only parent relationships record details for building graph schema?

{
	objectType: {
		parents: [
			{ 
				relationshipTag: "xx", // eg relationship type stored in graph
				linkType: "", // "Independent", // Dependent|Independent
				separateDependentLinkCreate: true, // for Dependent only, default is false
				objType: {
					serviceTag: "xx", // points to the parents serviceTag (maybe optional if in same service)
					objectType: "xx", // points to the parents objectTypes
				},
				storageResource: "graph" , // |eg:"dynamoDB" , used to find objectTypes added to graph schema
				properties: {
					{propertyName}: {
						//..
					}
				},
			},
			// ...
		],
		children: [
			{ 
				relationshipTag: "xx", // eg relationship type stored in graph
				objType: {
					serviceTag: "xx", // points to the childs serviceTag (maybe optional if in same service)
					objectType: "xx", // points to the childs objectTypes
				},
			},
			// ...
		],
	}
},

Generated S3 files

• generate multiple files for different uses, eg:
  1. list of saved fieldNames for Create
  2. list of saved+calculated for Update/Info pages
  3. graphSchemas
  4. relationships (used by Search/Sort Results)

Use Cases

Find Deployed Service Name

• other services can use fixed serviceTag to get deployed serviceName from serviceSchema on S3
• used to build resource names for external services
• eg when one service needs to send a message into an SNS belonging to a different service

Standard Create, Update, List, Delete pages

• List and Delete are maybe not required, use table data system instead.
• object schema can add validation information that can be used on the frontend to check before sending to backend, and by the backend to validate the data before handling

Create Object

• can configure what fields are shown
• requiredOnCreate fields must be shown

Edit Object

• users setup any number of pages for object types with configurable fields shown
• fields can be either display only or edit
• each field can adjust it's display properties (perhaps via cssStyles)

Menu Config

When adding menu items can add links to create, update, list, delete objects, user chooses the service then from that service's list of objects and what action is being performed. For update/delete perhaps links to a standard page that asks for the identifier before presenting the page.

Tabled Data

When viewing tabled data the frontend pulls the tableId's config from backend, then when requesting the data also requests the serviceTag > objectType schema for use when displaying the data.

Code Standardization

Code such as middleware validation schema and saving data to databases can be standardized.

Code Generation

Endpoints per object for actions such as Create/Delete/Update can be automatically generated from objectSchema.

Code Generation Structure

• npm for generic code generation, can be used in any project, includes functions for generating Source files from templates and developer files
• npm for per project specific files, eg templates for the project (Create/Update/.. code)
• Empty Service Template has GenerateCode.js script file in root dir that is run to generate code, it invokes a generation function from generic npm with param that points to per project npm's templates
• generated Source retains hook tags (and any developer added code), so if developer wants to update developer's file with updated template code they can generate code and simply copy generated Source to src folder

Graph Server Config

• S3 has a list of graphServerTag's linking to the GraphHandler serviceTag responsible for the graph
• multiple graphServerTags can point to one GraphHandler, combining graphs into one server
• when creating each GraphHandler's graph schemas, for each field split out the fields into each GraphHandler using the graphServerTag, if multiple graphServerTags for a field point to the same GraphHandler combine the fields to create GraphHandler's graph schema
• every GraphHandler an object is saved into will require it's identifiers
• when eg updating fields for an object separate the fields per GraphHandler before sending the request to update each graph

Extended Object Types

• Allows for one graph node to have multiple labels
• graph schema is created for both the core object and the extended object
• eg Media Manager's has a node schema for "media" object type, and Image service has a node schema for "image" object type
• the extended object builds it's schema by combining core + extended settings