I have a DynamoDB with nested values inside.
An Entry looks like the following:
Now I would like to scan all entries in the database to find all entries with a specific episodeGuid.
I tried this code (and some variants), but always with 0 results.
var params = {
TableName: "myTableName",
FilterExpression: "#episodeGuid = :myEpisode",
ExpressionAttributeNames: {
'#episodeGuid': 'attributes.playbackInfo.episodeGuid',
},
// ExpressionAttributeValues: { ":myEpisode": { "S": "podlove-2018-12-06t13:07:10+00:00-f8a9b2963f313e5" } }
ExpressionAttributeValues: { ":myEpisode": "podlove-2018-12-06t13:07:10+00:00-f8a9b2963f313e5" }
};
oDynamoDBClient.scan(params, async function (err, data) {
console.log('read return');
if (err) console.log(err, err.stack); // an error occurred
else {
console.log(data);
}
});
Can someone give me a hint how can I find my entries?
The filter is looking for an attribute named attributes.playbackInfo.episodeGuid as opposed to a nested attribute.
To look for a nested attribute, the expression needs to contain to ..
FilterExpression: "#attributes.#playbackInfo.#episodeGuid = :myEpisode",
ExpressionAttributeNames: {
'#attributes': 'attributes',
'#playbackInfo': 'playbackInfo',
'#episodeGuid': 'episodeGuid',
},
Related
Is there a way of making transactWriteItem return the document it updated?
const transactionParams = {
ReturnConsumedCapacity: "INDEXES",
TransactItems: [
{
Delete: {
TableName: reactionTableName,
Key: {
"SOME_PK_",
"SOME_SK_",
},
ReturnValues: 'ALL_OLD',
},
},
{
Update: {
TableName: reviewTableName,
Key: { PK: "SOME_PK", SK: "SOME_SK" },
ReturnValues: 'ALL_OLD',
},
},
],
};
try {
const result = await docClient.transactWrite(transactionParams).promise();
} catch (error) {
context.done(error, null);
}
For example in the above code get the documents that were touched (before or after update)?
No, TransactWriteItems API does not provide the ability to return values of a modified item, however, you could obtain those values using DynamoDB Streams, otherwise you would need to default to the singleton APIs UpdateItem/DeleteItem which are not ACID compliant together.
I'm attempting to set up my DynamoDB table so I can query the data via a rest API. My table has a partition key (id) which is a randomly generated ID, a sort key (name) and a List of strings (domain).
I have also set up a global secondary index for the "name" field.
I'm attempting to write a lambda that will search for items using both the name and possible search the domain array also. Is this possible? If so how do I set up the table as I'm currently getting this error:
Query key condition not supported
Here is my Lambda query code:
async function query(tableName, searchTerm) {
return new Promise((resolve, reject) => {
const params = {
IndexName: "nameIndex",
ExpressionAttributeNames: {
"#name": "name",
},
ExpressionAttributeValues: {
":topic": { S: searchTerm },
},
KeyConditionExpression: "begins_with(#name, :topic)",
TableName: tableName,
};
ddb.query(params, (err, data) => {
if (err) {
reject(err);
} else {
console.log("Success", data.Items);
resolve(data.Items);
}
});
});
}
A PK must be provided as a value. You can't do expressions like begins with on a PK.
Here are a lot of example programs doing queries with Node:
https://github.com/aws-samples/aws-dynamodb-examples/tree/master/DynamoDB-SDK-Examples/node.js/WorkingWithQueries
I need your help to update/add item in a list of list of DynamoDB.
I want to add and update a list that is composed by a list.
How can i do that? Thanks for your help
Here my example:
DATABASE
Item{1}
idProject:"15azeze-55ze"
dateCreationProjectString: 08/01/2018 14:6:32
environnements: List[1]
0 MAP {3}
idEnvironnement: "11-aa",
name:"Exemple Environnement"
tasks[0]
NodeJS code :
let newTask = {
authorTask : "Toto",
dateCreationTask: "01/01/1960",
idTask: "154-141-aa41",
nameTask: "Task name ..."
};
dynamodbdc.update({
TableName: "projects",
Key: { idProject: "15azeze-55ze", idEnvironnement:"11-aa" },
ReturnValues: 'ALL_NEW',
UpdateExpression: 'set #environnements.#tasks = list_append(if_not_exists(#environnements.#tasks, :empty_list), :newTask)',
ExpressionAttributeNames: {
'#environnements' : 'environnements',
'#tasks' : 'tasks',
},
ExpressionAttributeValues: {
':newTask': [newTask],
':empty_list': []
}
}, function(error, stdout) {
if(error){
console.log("error==", error)
else {
console.log("Nice thank you !!")
}
});
I would suggest to keep the tasks attribute as SET ('SS') which will simplify to NOT add the duplicate values. Otherwise, it would be difficult to fulfil the scenario.
Also, you may the index of the environments attribute list to form the update expression correctly. There is no options in the dynamodb api to workout the index automatically.
The below code should work if you define the tasks attribute as SET.
Insert item code:-
var params = {
TableName : table,
Item : {
"idProject" : "15azeze-55ze",
"dateCreationProjectString" : Date(),
"environnements" : [{
"idEnvironnement" : "11-aa",
"name" : "Example Environments",
"tasks" : docClient.createSet(["1"])
}]
}
};
console.log("Adding a new item...");
docClient.put(params, function(err, data) {
if (err) {
console.error("Unable to add item. Error JSON:", JSON.stringify(err,
null, 2));
} else {
console.log("Added item:", JSON.stringify(data, null, 2));
}
});
Sample update item working code:-
The ADD operation will ensure that it doesn't add duplicates to the SET
var docClient = new AWS.DynamoDB.DocumentClient();
var params = {
TableName: "projects",
Key: {
"idProject" : "15azeze-55ze"
},
UpdateExpression: 'ADD environnements['+0+'].tasks :tasksVal',
ExpressionAttributeValues: {
":tasksVal": docClient.createSet(["2"])
},
ReturnValues: "UPDATED_NEW"
};
console.log("Updating the item...");
docClient.update(params, function (err, data) {
if (err) {
console.error("Unable to update item. Error JSON:", JSON.stringify(err, null, 2));
} else {
console.log("UpdateItem succeeded:", JSON.stringify(data));
}
});
I am trying to search a non primary key using AWS Lambda and integrating it into the Alexa Skills Kit. I am very new to using DynamoDB and Alexa Skills Kit and I'm struggling to find any solutions to this online. The basic premise for what I am trying to do is querying the table yesno with two columns, id and message. Only looking through the message column to find a match with the text i specify in params.
Here is the Lambda code I am working with:
const AWSregion = 'eu-west-1';
const Alexa = require('alexa-sdk');
const AWS = require('aws-sdk');
//params for searching table
const params = {
TableName: 'yesno',
Key:{ "message": 'Ben Davies' }
};
AWS.config.update({
region: AWSregion
});
exports.handler = function(event, context, callback) {
var alexa = Alexa.handler(event, context);
// alexa.appId = 'amzn1.echo-sdk-ams.app.1234';
// alexa.dynamoDBTableName = 'YourTableName'; // creates new table for session.attributes
alexa.registerHandlers(handlers);
alexa.execute();
};
const handlers = {
'LaunchRequest': function () {
this.response.speak('welcome to magic answers. ask me a yes or no question.').listen('try again');
this.emit(':responseReady');
},
'MyIntent': function () {
var MyQuestion = this.event.request.intent.slots.MyQuestion.value;
console.log('MyQuestion : ' + MyQuestion);
readDynamoItem(params, myResult=>{
var say = MyQuestion;
say = myResult;
say = 'you asked, ' + MyQuestion + '. I found a reckord for: ' + myResult;
this.response.speak(say).listen('try again');
this.emit(':responseReady');
});
},
'AMAZON.HelpIntent': function () {
this.response.speak('ask me a yes or no question.').listen('try again');
this.emit(':responseReady');
},
'AMAZON.CancelIntent': function () {
this.response.speak('Goodbye!');
this.emit(':responseReady');
},
'AMAZON.StopIntent': function () {
this.response.speak('Goodbye!');
this.emit(':responseReady');
}
};
// END of Intent Handlers {} ========================================================================================
// Helper Function =================================================================================================
function readDynamoItem(params, callback) {
var AWS = require('aws-sdk');
AWS.config.update({region: AWSregion});
var dynamodb = new AWS.DynamoDB();
console.log('reading item from DynamoDB table');
dynamodb.query(params, function (err, data) {
if (err) console.log(err, err.stack); // an error occurred
else{
console.log(data); // successful response
callback(data.Item.message);
}
});
}
I know I am probably doing this completely wrong but there isn't much online for integrating DynamoDB with an Alexa Skill and the only thing i was able to find was searching by ID. This doesn't work for what i want to do without pulling all the items from the table into a map or a list, and seeing as I want to create a big database it seems quite inefficient.
On the Alexa side of things I am receiving the following service request when testing the code:
{
"session": {
"new": true,
"sessionId": "SessionId.f9558462-6db8-4bf5-84aa-22ee0920ae95",
"application": {
"applicationId": "amzn1.ask.skill.9f280bf7-d506-4d58-95e8-b9e93a66a420"
},
"attributes": {},
"user": {
"userId": "amzn1.ask.account.AF5IJBMLKNE32GEFQ5VFGVK2P4YQOLVUSA5YPY7RNEMDPKSVCBRCPWC3OBHXEXAHROBTT7FGIYA7HJW2PMEGXWHF6SQHRX3VA372OHPZZJ33K7S4K7D6V3PXYB6I72YFIQBHMJ4QGJW3NS3E2ZFY5YFSBOEFW6V2E75YAZMRQCU7MNYPJUMJSUISSUA2WF2RA3CIIDCSEY35TWI"
}
},
"request": {
"type": "IntentRequest",
"requestId": "EdwRequestId.7310073b-981a-41f8-9fa5-03d1b28c5aba",
"intent": {
"name": "MyIntent",
"slots": {
"MyQuestion": {
"name": "MyQuestion",
"value": "erere"
}
}
},
"locale": "en-US",
"timestamp": "2018-01-25T14:18:40Z"
},
"context": {
"AudioPlayer": {
"playerActivity": "IDLE"
},
"System": {
"application": {
"applicationId": "amzn1.ask.skill.9f280bf7-d506-4d58-95e8-b9e93a66a420"
},
"user": {
"userId": "amzn1.ask.account.AF5IJBMLKNE32GEFQ5VFGVK2P4YQOLVUSA5YPY7RNEMDPKSVCBRCPWC3OBHXEXAHROBTT7FGIYA7HJW2PMEGXWHF6SQHRX3VA372OHPZZJ33K7S4K7D6V3PXYB6I72YFIQBHMJ4QGJW3NS3E2ZFY5YFSBOEFW6V2E75YAZMRQCU7MNYPJUMJSUISSUA2WF2RA3CIIDCSEY35TWI"
},
"device": {
"supportedInterfaces": {}
}
}
},
"version": "1.0"
}
And I am receiving a service response error simply saying 'The response is invalid'
Any help with this would be greatly appreciated
I would like to help you in dynamo db part.
In order to access non primary key columns in dynamodb you should perform scan operation.
For your table (yesno), id is a primary key and message is an additional column.
Snippet to access non primary key column [Message]
var dynamodb = new AWS.DynamoDB();
var params = {
TableName: 'yesno',
FilterExpression: 'message = :value',
ExpressionAttributeValues: {
':value': {"S": "Ben Davies"}
}
};
dynamodb.scan(params, function(err, data) {
if (err) // an error occurred
else console.log(data); // successful response
});
Snippet to access primary key column [Id]
var docClient = new AWS.DynamoDB.DocumentClient();
//Get item by key
var params = {
TableName: 'sis_org_template',
Key: { "id": "1"}
};
docClient.get(params, function(err, data) {
if (err) // an error occurred
else console.log(data); // successful response
});
So this should be simple...
I want to append a string to a StringSet in a DynamoDB if it exists, or create the StringSet property if it doesn't and set the value. If we could initialize the StringSet on creation with an empty array, it would be fine, but alas we can not.
Here's what I have so far:
const companiesTable = 'companies';
dynamodb.updateItem({
TableName: companiesTable,
Key: {
id: {
S: company.id
}
},
UpdateExpression: 'ADD socialAccounts = list_append(socialAccount, :socialAccountId)',
ExpressionAttributeValues: {
':socialAccountId': {
'S': [socialAccountId]
}
},
ReturnValues: "ALL_NEW"
}, function(err, companyData) {
if (err) return cb({ error: true, message: err });
const response = {
error: false,
message: 'Social account created',
socialAccountData
};
cb(response);
});
I've also tried...
UpdateExpression: 'SET socialAccounts = list_append(socialAccounts, :socialAccountId)',
ExpressionAttributeValues: {
':socialAccountId': {
S: socialAccountId
}
},
and...
UpdateExpression: 'ADD socialAccounts = :socialAccountId',
ExpressionAttributeValues: {
':socialAccountId': {
S: socialAccountId
}
},
and...
UpdateExpression: 'SET socialAccounts = [:socialAccountId]',
ExpressionAttributeValues: {
':socialAccountId': socialAccountId
},
and...
UpdateExpression: 'ADD socialAccounts = :socialAccountId',
ExpressionAttributeValues: {
':socialAccountId': socialAccountId
},
Among about every other variation of the above. Am I dumb? Is DynamoDB not capable of simple write/updates to an array type field? Do I REALLY have to lookup the item first to see if it has that field before I try to either add or set that field, because I can't instantiate that field with an empty array?
The ADD action handles the create/update logic, but only supports numbers and sets. You are trying to add a string type 'S'. You need to wrap this string in an array and pass it as a string set 'SS'. You also don't need the equals sign.
Your UpdateExpression and ExpressionAttributeValues should look like this:
UpdateExpression: 'ADD socialAccounts :socialAccountId',
ExpressionAttributeValues: {
':socialAccountId': {
'SS': [socialAccountId]
}
},
More information about updating items can be found here