Copying one table to another in DynamoDB - amazon-web-services

What's the best way to identically copy one table over to a new one in DynamoDB?
(I'm not worried about atomicity).

Create a backup(backups option) and restore the table with a new table name. That would get all the data into the new table.
Note: Takes considerable amount of time depending on the table size

I just used the python script, dynamodb-copy-table, making sure my credentials were in some environment variables (AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY), and it worked flawlessly. It even created the destination table for me.
python dynamodb-copy-table.py src_table dst_table
The default region is us-west-2, change it with the AWS_DEFAULT_REGION env variable.

AWS Pipeline provides a template which can be used for this purpose: "CrossRegion DynamoDB Copy"
See: http://docs.aws.amazon.com/datapipeline/latest/DeveloperGuide/dp-crossregion-ddb-create.html
The result is a simple pipeline that looks like:
Although it's called CrossRegion you can easily use it for the same region as long the destination table name is different (Remember that table names are unique per account and region)

You can use Scan to read the data and save it to the new table.
On the AWS forums a guy from the AWS team posted another approach using EMR: How Do I Duplicate a Table?

Here's one solution to copy all items from one table to another, just using shell scripting, the AWS CLI and jq. Will work OK for smallish tables.
# exit on error
set -eo pipefail
# tables
TABLE_FROM=<table>
TABLE_TO=<table>
# read
aws dynamodb scan \
--table-name "$TABLE_FROM" \
--output json \
| jq "{ \"$TABLE_TO\": [ .Items[] | { PutRequest: { Item: . } } ] }" \
> "$TABLE_TO-payload.json"
# write
aws dynamodb batch-write-item --request-items file://"$TABLE_TO-payload.json"
# clean up
rm "$TABLE_TO-payload.json"
If you both tables to be identical, you'd want to delete all items in TABLE_TO first.

DynamoDB now supports importing from S3.
https://aws.amazon.com/blogs/database/amazon-dynamodb-can-now-import-amazon-s3-data-into-a-new-table/
So, probably in almost all use cases, the easiest and cheapest way to replicate a table is
Use "Export to S3" feature to dump entire table into S3. Since this uses backup to generate the dump, table's throughput is not affected, and is very fast as well. You need to have backups (PITR) enabled. See https://aws.amazon.com/blogs/aws/new-export-amazon-dynamodb-table-data-to-data-lake-amazon-s3/
Use "Import from S3" to import the dump created in step 1. This automatically requires you to create a new table.

Use this node js module : copy-dynamodb-table

This is a little script I made to copy the contents of one table to another.
It's based on the AWS-SDK v3. Not sure how well it would scale to big tables but as a quick and dirty solution it does the job.
It gets your AWS credentials from a profile in ~/.aws/credentials change default to the name of the profile you want to use.
Other than that it takes two args one for the source table and one for destination
const { fromIni } = require("#aws-sdk/credential-providers");
const { DynamoDBClient, ScanCommand, PutItemCommand } = require("#aws-sdk/client-dynamodb");
const ddbClient = new DynamoDBClient({
credentials: fromIni({profile: "default"}),
region: "eu-west-1",
});
const args = process.argv.slice(2);
console.log(args)
async function main() {
const { Items } = await ddbClient.send(
new ScanCommand({
TableName: args[0],
})
);
console.log("Successfully scanned table")
console.log("Copying", Items.length, "Items")
const putPromises = [];
Items.forEach((item) => {
putPromises.push(
ddbClient.send(
new PutItemCommand({
TableName: args[1],
Item: item,
})
)
);
});
await Promise.all(putPromises);
console.log("Successfully copied table")
}
main();
Usage
node copy-table.js <source_table_name> <destination_table_name>

Python + boto3 🚀
The script is idempotent as far as you maintain the same Keys.
import boto3
def migrate(source, target):
dynamo_client = boto3.client('dynamodb', region_name='us-east-1')
dynamo_target_client = boto3.client('dynamodb', region_name='us-west-2')
dynamo_paginator = dynamo_client.get_paginator('scan')
dynamo_response = dynamo_paginator.paginate(
TableName=source,
Select='ALL_ATTRIBUTES',
ReturnConsumedCapacity='NONE',
ConsistentRead=True
)
for page in dynamo_response:
for item in page['Items']:
dynamo_target_client.put_item(
TableName=target,
Item=item
)
if __name__ == '__main__':
migrate('awesome-v1', 'awesome-v2')

On November 29th, 2017 Global Tables was introduced. This may be useful depending on your use case, which may not be the same as the original question. Here are a few snippets from the blog post:
Global Tables – You can now create tables that are automatically replicated across two or more AWS Regions, with full support for multi-master writes, with a couple of clicks. This gives you the ability to build fast, massively scaled applications for a global user base without having to manage the replication process.
...
You do not need to make any changes to your existing code. You simply send write requests and eventually consistent read requests to a DynamoDB endpoint in any of the designated Regions (writes that are associated with strongly consistent reads should share a common endpoint). Behind the scenes, DynamoDB implements multi-master writes and ensures that the last write to a particular item prevails. When you use Global Tables, each item will include a timestamp attribute representing the time of the most recent write. Updates are propagated to other Regions asynchronously via DynamoDB Streams and are typically complete within one second (you can track this using the new ReplicationLatency and PendingReplicationCount metrics).

Another option is to download the table as a .csv file and upload it with the following snippet of code.
This also eliminates the need for providing your AWS credentials to a packages such as the one #ezzat suggests.
Create a new folder and add the following two files and your exported table
Edit uploadToDynamoDB.js and add the filename of the exported table and your table name
Run npm install in the folder
Run node uploadToDynamodb.js
File: Package.json
{
"name": "uploadtodynamodb",
"version": "1.0.0",
"description": "",
"main": "uploadToDynamoDB.js",
"author": "",
"license": "ISC",
"dependencies": {
"async": "^3.1.1",
"aws-sdk": "^2.624.0",
"csv-parse": "^4.8.5",
"fs": "0.0.1-security",
"lodash": "^4.17.15",
"uuid": "^3.4.0"
}
}
File: uploadToDynamoDB.js
var fs = require('fs');
var parse = require('csv-parse');
var async = require('async');
var _ = require('lodash')
var AWS = require('aws-sdk');
// If your table is in another region, make sure to update this
AWS.config.update({ region: "eu-central-1" });
var ddb = new AWS.DynamoDB({ apiVersion: '2012-08-10' });
var csv_filename = "./TABLE_CSV_EXPORT_FILENAME.csv";
var tableName = "TABLENAME"
function prepareData(data_chunk) {
const items = data_chunk.map(obj => {
const keys = Object.keys(obj)
let attr = Object.values(obj)
attr = attr.map(a => {
let newAttr;
// Can we make this an integer
if (isNaN(Number(a))) {
newAttr = { "S": a }
} else {
newAttr = { "N": a }
}
return newAttr
})
let item = _.zipObject(keys, attr)
return {
PutRequest: {
Item: item
}
}
})
var params = {
RequestItems: {
[tableName]: items
}
};
return params
}
rs = fs.createReadStream(csv_filename);
parser = parse({
columns : true,
delimiter : ','
}, function(err, data) {
var split_arrays = [], size = 25;
while (data.length > 0) {
split_arrays.push(data.splice(0, size));
}
data_imported = false;
chunk_no = 1;
async.each(split_arrays, function(item_data, callback) {
const params = prepareData(item_data)
ddb.batchWriteItem(
params,
function (err, data) {
if (err) {
console.log("Error", err);
} else {
console.log("Success", data);
}
});
}, function() {
// run after loops
console.log('all data imported....');
});
});
rs.pipe(parser);

It's been a very long time since the question was posted and AWS has been continuously improvising features. At the time of writing this answer, we have the option to export the Table to S3 bucket then use the import feature to import this data from S3 into a new table which automatically will re-create a new table with the data. Plese refer this blog for more idea on export & import
Best part is that you get to change the name, PK or SK.
Note: You have to enable PITR (might incur additional costs). Always best to refer documents.

Here is another simple python util script for this: ddb_table_copy.py. I use it often.
usage: ddb_table_copy.py [-h] [--dest-table DEST_TABLE] [--dest-file DEST_FILE] source_table
Copy all DynamoDB items from SOURCE_TABLE to either DEST_TABLE or DEST_FILE. Useful for migrating data during a stack teardown/re-creation.
positional arguments:
source_table Name of source table in DynamoDB.
optional arguments:
-h, --help show this help message and exit
--dest-table DEST_TABLE
Name of destination table in DynamoDB.
--dest-file DEST_FILE
2) a valid file path string to save the items to, e.g. 'items.json'.

Related

How to return an entire Datastore table by name using Node.js on a Google Cloud Function

I want to retrieve a table (with all rows) by name. I want to HTTP request using something like this on the body {"table": user}.
Tried this code without success:
'use strict';
const {Datastore} = require('#google-cloud/datastore');
// Instantiates a client
const datastore = new Datastore();
exports.getUsers = (req, res) => {
//Get List
const query = this.datastore.createQuery('users');
this.datastore.runQuery(query).then(results => {
const customers = results[0];
console.log('User:');
customers.forEach(customer => {
const cusKey = customer[this.datastore.KEY];
console.log(cusKey.id);
console.log(customer);
});
})
.catch(err => { console.error('ERROR:', err); });
}
Google Datastore is a NoSQL database that is working with entities and not tables. What you want is to load all the "records" which are "key identifiers" in Datastore and all their "properties", which is the "columns" that you see in the Console. But you want to load them based the "Kind" name which is the "table" that you are referring to.
Here is a solution on how to retrieve all the key identifiers and their properties from Datastore, using HTTP trigger Cloud Function running in Node.js 8 environment.
Create a Google Cloud Function and choose the trigger to HTTP.
Choose the runtime to be Node.js 8
In index.js replace all the code with this GitHub code.
In package.json add:
{
"name": "sample-http",
"version": "0.0.1",
"dependencies": {
"#google-cloud/datastore": "^3.1.2"
}
}
Under Function to execute add loadDataFromDatastore, since this is the name of the function that we want to execute.
NOTE: This will log all the loaded records into the Stackdriver logs
of the Cloud Function. The response for each record is a JSON,
therefore you will have to convert the response to a JSON object to
get the data you want. Get the idea and modify the code accordingly.

Google Cloud Datastore query values in array

I have entities that look like that:
{
name: "Max",
nicknames: [
"bestuser"
]
}
how can I query for nicknames to get the name?
I have created the following index,
indexes:
- kind: users
properties:
- name: name
- name: nicknames
I use the node.js client library to query the nickname,
db.createQuery('default','users').filter('nicknames', '=', 'bestuser')
the response is only an empty array.
Is there a way to do that?
You need to actually fetch the query from datastore, not just create the query. I'm not familiar with the nodejs library, but this is the code given on the Google Cloud website:
datastore.runQuery(query).then(results => {
// Task entities found.
const tasks = results[0];
console.log('Tasks:');
tasks.forEach(task => console.log(task));
});
where query would be
const query = db.createQuery('default','users').filter('nicknames', '=', 'bestuser')
Check the documentation at https://cloud.google.com/datastore/docs/concepts/queries#datastore-datastore-run-query-nodejs
The first point to notice is that you don't need to create an index to this kind of search. No inequalities, no orders and no projections, so it is unnecessary.
As Reuben mentioned, you've created the query but you didn't run it.
ds.runQuery(query, (err, entities, info) => {
if (err) {
reject(err);
} else {
response.resultStatus = info.moreResults;
response.cursor = info.moreResults == TNoMoreResults? null: info.endCursor;
resolve(entities);
};
});
In my case, the response structure was made to collect information on the cursor (if there is more data than I've queried because I've limited the query size using limit) but you don't need to anything more than the resolve(entities)
If you are using the default namespace you need to remove it from your query. Your query needs to be like this:
const query = db.createQuery('users').filter('nicknames', '=', 'bestuser')
I read the entire plob as a string to get the bytes of a binary file here. I imagine you simply parse the Json per your requirement

Firehose record format conversion partitions

I tried to to use the new firehose feature "record format conversion" to save my events as parquet files for athena or hive aggregations. You have to select the table from your glue catalog, but firehose ignores the defined partions, and instead saves the files in the structure YYYY/MM/DD/HH/. The data also is missing the defined partition columns. This would be ok, if it has used it for partitioning.
Is there a API configuration, or something else, to force to use the table partitioning?
I have exact the same issue, even with same partitioning
So you have to use AWS lambda to achieve what you want
one to move files generated by Firehose to bucket that is used by Athena.
another one to trigger refresh Athena table, as it will not see new folders
(I don't put all triggers, but this should be just a call 'MSCK REPAIR TABLE your_table_name;')
For the first one I choose NodeJs, as this is really simple and really fast.
~ 3 seconds to move 120MB file with minimum AWS allowed 128MB RAM memory allocation(files generated by Firehose will be approximate 64MB max)
Node js project structure
package.json
{
"name": "your.project",
"version": "1.0.0",
"description": "Copy generated partitioned files by Firehose to valid partitioned files for Athena",
"main": "index.js",
"dependencies": {
"async": "^2.6.1"
}
}
And index.js
const aws = require('aws-sdk');
const async = require('async');
const s3 = new aws.S3();
const dstBucket = 'PUT_YOUR_BUCKET_NAME_HERE';
var util = require('util');
exports.handler = (event, context, callback) => {
const srcBucket = event.Records[0].s3.bucket.name;
const srcKey = event.Records[0].s3.object.key;
const split = srcKey.split('/');
const dstKey = `event_year=${split[0]}/event_month=${split[1]}/event_day=${split[2]}/event_hour=${split[3]}/${split[4]}`;
console.log("Reading options from event:\n", util.inspect(event, {depth: 10}));
async.waterfall([
function copy(next) {
s3.copyObject({
Bucket: dstBucket,
CopySource: `${srcBucket}/${srcKey}`,
Key: dstKey
}, next);
},
function deleteOriginal(copyResult, next) {
s3.deleteObject({
Bucket: srcBucket,
Key: srcKey
}, next);
}
], function (err) {
if (err) {
console.error(`Failed: ${srcBucket}/${srcKey} => ${dstBucket}/${dstKey} to move FireHose partitioned object to Athena partitioned object. Error: ${err}`);
} else {
console.log(`Success: ${srcBucket}/${srcKey} => ${dstBucket}/${dstKey} moved FireHose partitioned object to Athena partitioned object`);
}
callback(null, 'move success');
}
);
};
Just update some data to be valid for your case.
And one more issue that I got, is when build a project with
npm install
and zip it, it was something not correct in AWS unzip, so I have to update path to my index.js.
And this works.
You can also find this line
console.log("Reading options from event:\n", util.inspect(event, {depth: 10}));
It can be removed, but greatly helps to understand details of processing object

Access to AWS Kinesis tables in DynamoDB using AWS Cli

I am new to AWS Kinesis. Trying to learn how to build distributed application using AWS DynamoDB. Could someone tell me how to access the tables in DynamoDB used by my streams in AWS Kinesis using the AWS Cli? Can I query the tables?
Surely. Kinesis-stream uses Amazon Dynamodb table for consumer offset management.
your table will have the same name as your consumer name (defined via KCL). you can see all consumer_offset_tables via console (https://console.aws.amazon.com/dynamodb/home)
consumer could be running in multiple instances, but only one instance (THE leaseOwner)can consume from one partition (or Shard what Kinesis calls it). If this consumer fails another instance of the same consumer will take over and continue processing from the checkpoint.
checkpoint is the last processed event
the shard that the consumer instance is processing is called leaseKey which is unique for a table.
The data structure of the key value based document in Dynamodb would be as below,
where
"S" - Char array
"N" - Number
{
"leaseOwner": {
"S": "SmartConsumerStream_Consumer-192.168.1.83"
},
"checkpoint": {
"S": "49570630332110756564477900867375857710984404992079691778"
},
"checkpointSubSequenceNumber": {
"N": "0"
},
"leaseCounter": {
"N": "16"
},
"leaseKey": {
"S": "shardId-000000000000"
},
"ownerSwitchesSinceCheckpoint": {
"N": "0"
}
}
You can use Dynamodb API to get the current offset for given partitionKey or leaseKey. You can only query by leaseKey because thats the indexed key in table. Its created by Kinesis-stream itself.
You can use the stream-driver I'm writing at here, which gives you interface to get the consumer offset very very easily.
Here are kinesis-stream tests which might be helpful too.
In summary, get the consumer offset using JAVA api
-- put aws credentials in ~/.aws/credentials
public Map<String, String> getConsumerPosition() {
DynamoDB dynamoDB = new DynamoDB(getOffsetConnection()); //
Table consumerOffsetTable = dynamoDB.getTable("your_consumer_id");
Map<String, Object> leaseOwner = consumerOffsetTable.getItem("leaseKey", "shardId-000000000000").asMap();
return new HashMap<String, String>(){{
put(leaseOwner.get("leaseKey").toString(), leaseOwner.get("checkpoint").toString());
}};
}
public AmazonDynamoDB getOffsetConnection() {
AmazonDynamoDBClient dynamoDB = new AmazonDynamoDBClient(getAuthProfileCredentials(), getHttpConfiguration());
return dynamoDB;
}
private ProfileCredentialsProvider getAuthProfileCredentials() {
return new ProfileCredentialsProvider("your-aws-auth-profile_in_~/.aws/credentials");
}
private ClientConfiguration getHttpConfiguration() {
ClientConfiguration clientConfiguration = new ClientConfiguration();
return clientConfiguration;
}
Hope it helps, let me know if I can help some other ways.

Writing a single file to multiple s3 buckets with gulp-awspublish

I have a simple single-page app, that is deployed to an S3 bucket using gulp-awspublish. We use inquirer.js (via gulp-prompt) to ask the developer which bucket to deploy to.
Sometimes the app may be deployed to several S3 buckets. Currently, we only allow one bucket to be selected, so the developer has to gulp deploy for each bucket in turn. This is dull and prone to error.
I'd like to be able to select multiple buckets and deploy the same content to each. It's simple to select multiple buckets with inquirer.js/gulp-prompt, but not simple to generate arbitrary multiple S3 destinations from a single stream.
Our deploy task is based upon generator-webapp's S3 recipe. The recipe suggests gulp-rename to rewrite the path to write to a specific bucket. Currently our task looks like this:
gulp.task('deploy', ['build'], () => {
// get AWS creds
if (typeof(config.awsCreds) !== 'object') {
return console.error('No config.awsCreds settings found. See README');
}
var dirname;
const publisher = $.awspublish.create({
key: config.awsCreds.key,
secret: config.awsCreds.secret,
bucket: config.awsCreds.bucket
});
return gulp.src('dist/**/*.*')
.pipe($.prompt.prompt({
type: 'list',
name: 'dirname',
message: 'Using the ‘' + config.awsCreds.bucket + '’ bucket. Which hostname would you like to deploy to?',
choices: config.awsCreds.dirnames,
default: config.awsCreds.dirnames.indexOf(config.awsCreds.dirname)
}, function (res) {
dirname = res.dirname;
}))
.pipe($.rename(function(path) {
path.dirname = dirname + '/dist/' + path.dirname;
}))
.pipe(publisher.publish())
.pipe(publisher.cache())
.pipe($.awspublish.reporter());
});
It's hopefully obvious, but config.awsCreds might look something like:
awsCreds: {
dirname: 'default-bucket',
dirnames: ['default-bucket', 'other-bucket', 'another-bucket']
}
Gulp-rename rewrites the destination path to use the correct bucket.
We can select multiple buckets by using "checkbox" instead of "list" for the gulp-prompt options, but I'm not sure how to then deliver it to multiple buckets.
In a nutshell, if $.prompt returns an array of strings instead of a string, how can I write the source to multiple destinations (buckets) instead of a single bucket?
Please keep in mind that gulp.dest() is not used -- only gulp.awspublish() -- and we don't know how many buckets might be selected.
Never used S3, but if I understand your question correctly a file js/foo.js should be renamed to default-bucket/dist/js/foo.js and other-bucket/dist/js/foo.js when the checkboxes default-bucket and other-bucket are selected?
Then this should do the trick:
// additionally required modules
var path = require('path');
var through = require('through2').obj;
gulp.task('deploy', ['build'], () => {
if (typeof(config.awsCreds) !== 'object') {
return console.error('No config.awsCreds settings found. See README');
}
var dirnames = []; // array for selected buckets
const publisher = $.awspublish.create({
key: config.awsCreds.key,
secret: config.awsCreds.secret,
bucket: config.awsCreds.bucket
});
return gulp.src('dist/**/*.*')
.pipe($.prompt.prompt({
type: 'checkbox', // use checkbox instead of list
name: 'dirnames', // use different result name
message: 'Using the ‘' + config.awsCreds.bucket +
'’ bucket. Which hostname would you like to deploy to?',
choices: config.awsCreds.dirnames,
default: config.awsCreds.dirnames.indexOf(config.awsCreds.dirname)
}, function (res) {
dirnames = res.dirnames; // store array of selected buckets
}))
// use through2 instead of gulp-rename
.pipe(through(function(file, enc, done) {
dirnames.forEach((dirname) => {
var f = file.clone();
f.path = path.join(f.base, dirname, 'dist',
path.relative(f.base, f.path));
this.push(f);
});
done();
}))
.pipe(publisher.cache())
.pipe($.awspublish.reporter());
});
Notice the comments where I made changes from the code you posted.
What this does is use through2 to clone each file passing through the stream. Each file is cloned as many times as there were bucket checkboxes selected and each clone is renamed to end up in a different bucket.