Adding support for list_append

[fishcharlie]

Summary:

This PR adds support for list_append when updating a document.

Code sample:

Schema

{
	id: {
		type: Number,
		validate: function(v) {
			return v > 0;
		}
	},
	items: {
		type: "list",
		list: [{
			name: {
				type: String,
				required: true
			},
			amount: {
				type: Number,
				required: true
			}
		}]
	}
}

Model

dynamoose.model('Cat', schema);

General

Cats.Cat13.create({
	id: 1000,
	items: [{
		name: "item 2",
		amount: 25
	}]
}, function() {
	Cats.Cat13.update({
		id: 1000
	}, {
		$ADD: {
			items: [{
				name: "item 1",
				amount: 50
			}]
		}
	}, function(err, data) {
		should.not.exist(err);
		should.exist(data);
		data.id.should.eql(1000);
		data.items.should.eql([{
			name: "item 2",
			amount: 25
		}, {
			name: "item 1",
			amount: 50
		}]);
		Cats.Cat13.get(1000, function(err, cat) {
			should.not.exist(err);
			should.exist(cat);
			cat.id.should.eql(1000);
			cat.items.should.eql([{
				name: "item 2",
				amount: 25
			}, {
				name: "item 1",
				amount: 50
			}]);
			done();
		});
	});
});

Other information:

• Related issue: How to do a list_append? How to push / add / append an item to an array / list? #395 @arthurvi

Type (select 1):

• Bug fix
• Feature implementation
• Documentation improvement
• Testing improvement
• Test added to report bug (GitHub issue #--- @---)
• Something not listed here

Is this a breaking change? (select 1):

• 🚨 YES 🚨
• No
• I'm not sure

Is this ready to be merged into Dynamoose? (select 1):

• Yes
• No

Are all the tests currently passing on this PR? (select 1):

• Yes
• No

Other:

• I have searched through the GitHub pull requests to ensure this PR has not already been submitted
• I have updated the Dynamoose documentation (if required) given the changes I made
• I have added/updated the Dynamoose test cases (if required) given the changes I made
• I have run npm test from the root of the project directory to ensure all tests continue to pass
• I agree that all changes made in this pull request may be distributed and are made available in accordance with the Dynamoose license
• All of my commits and commit messages are detailed, explain what changes were made, and are easy to follow and understand
• I have confirmed that all my code changes are indented properly using 2 spaces
• I have filled out all fields above

[coveralls]

Pull Request Test Coverage Report for Build 863

• 15 of 15 (100.0%) changed or added relevant lines in 1 file are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.05%) to 85.593%

---

Files with Coverage Reduction	New Missed Lines	%
lib/Table.js	2	78.59%

Totals
Change from base Build 853:	-0.05%
Covered Lines:	2217
Relevant Lines:	2513

---

💛 - Coveralls

[patrickianco]

Hello I'm having problems with the append to list function. I keep getting the error

message: 'Invalid UpdateExpression: Incorrect operand type for operator or function; operator: ADD, operand type: STRING'

I have the following schema
const schema = new dynamoose.Schema( { messenger_id: { type: String, hashKey: true }, is_active: { type: Boolean, required: true }, first_name: { type: String }, last_name: { type: String }, body: { type: "list", list: [ { text: { type: String, required: true }, attachments: { type: [Object], required: true }, type: { type: String, enum: ["text", "image", "template"], required: true }, is_echo: { type: Boolean, required: true }, timestamp: { type: Date, required: true } } ] } }, { useDocumentTypes: false } );

const model = dynamoose.model('livechat', schema);

Here is the create item
model .create({ messenger_id: 12345, is_active: true, first_name: "Patrick", last_name: "Co", body: [ { text: "Hello", attachments: [], type: "text", is_echo: true, timestamp: Date.now() } ] })

Here is the update
model .update( { messenger_id: 12345 }, { $ADD: { body: [ { text: "Hello po", attachments: [], type: "text", is_echo: true, timestamp: Date.now() } ] } } )