Develop Reference

How to use UpdateEventSourceMappingRequest in java?

I'm trying to use something like this:
UpdateEventSourceMappingRequest request = new UpdateEventSourceMappingRequest()
.withFunctionName("arn:aws:lambda:us-east-1:9999999999:function:"+functionName)
.withEnabled(false);
But I received a error because I have to use .withUUID(uuid):
UpdateEventSourceMappingRequest request = new UpdateEventSourceMappingRequest()
.withUUID(uuid))
.withFunctionName("arn:aws:lambda:us-east-1:9999999999:function:"+functionName)
.withEnabled(false);
I don't know how to get the value of uuid ( uuid from aws lambda ).
Can you help me with the solution to my problem ?

You need to provide the UUID identifier of the event source mapping to update it (and this field is mandatory). Update-request is not intended to create it.
When you create an event source mapping (here) - aws should return a response with a UUID identifier which you then may use in the update request.

That's the solution that I founded:
String strUUID = "";
ListEventSourceMappingsRequest requestList = new ListEventSourceMappingsRequest()
.withEventSourceArn("arn:aws:sqs:us-east-1:9999999999:test");
ListEventSourceMappingsResult result = awsLambda.listEventSourceMappings(requestList);
List<EventSourceMappingConfiguration> eventSourceMappings = result.getEventSourceMappings();
for (EventSourceMappingConfiguration eventLambda : eventSourceMappings) {
strUUID = eventLambda.getUUID();
}
System.out.println("Output UUID " + strUUID);
We have to use the ARN of the SQS that's trigger of the aws lambda.

AWS SSM parameter store not fetching all key/values

Could someone let me know why the below code only fetching few entries from the parameter store ?
GetParametersByPathRequest getParametersByPathRequest = new GetParametersByPathRequest();
getParametersByPathRequest.withPath("/").setRecursive(true);
getParametersByPathRequest.setWithDecryption(true);
GetParametersByPathResult result = client.getParametersByPath(getParametersByPathRequest);
result.getParameters().forEach(parameter -> {
System.out.println(parameter.getName() + " - > " + parameter.getValue());
});

GetParametersByPath is a paged operation. After each call you must retrieve NextToken from the result object, and if it's not null and not empty you must make another call with it added to the request.
Here's an example using DescribeParameters, which has the same behavior:
DescribeParametersRequest request = new DescribeParametersRequest();
DescribeParametersResult response;
do
{
response = client.describeParameters(request);
for (ParameterMetadata param : response.getParameters())
{
// do something with metadata
}
request.setNextToken(response.getNextToken());
}
while ((response.getNextToken() != null) && ! respose.getNextToken.isEmpty());

Here is the code, based on the code above, for the new 2.0 version of AWS SSM manager. Notice I have set the maxResults to 1 to prove out the loop. You will want to remove that. AWS has mentioned that in the new code they wanted to emphasize immutability.
Using this dependency:
<dependency>
<groupId>software.amazon.awssdk</groupId>
<artifactId>ssm</artifactId>
<version>2.10.32</version>
</dependency>
I came up with this code:
private void refreshCache() {
StopWatch sw = StopWatch.createStarted();
GetParametersByPathRequest request = GetParametersByPathRequest.builder()
.path(prefix)
.withDecryption(useDecryption)
.maxResults(1)
.build();
GetParametersByPathResponse response;
do {
response = ssm.getParametersByPath(request);
for (Parameter p : response.parameters()) {
//do something with the values.
}
request = GetParametersByPathRequest.builder()
.path(prefix)
.withDecryption(useDecryption)
.nextToken(response.nextToken())
.maxResults(1)
.build();
}
while (StringUtils.isNotBlank(response.nextToken()));
LOG.trace("Refreshed parameters in {}ms", sw.getTime());
}

private void getSsmParams() {
AWSSimpleSystemsManagement client = AWSSimpleSystemsManagementClientBuilder.defaultClient();
GetParametersByPathRequest request = new GetParametersByPathRequest();
request.withRecursive(true);
request.withPath('/your/path/parameterName').setWithDecryption(true);
GetParametersByPathResult response;
do {
response = client.getParametersByPath(request);
for (Parameter p : response.parameters()) {
//do something with the values. maybe add to a list
}
request.setNextToken(response.getNextToken())
}
while (StringUtils.isNotBlank(response.getNextToken()));
}
Above piece of code worked for me .ssm only sends 10 parameters at a time, so if you want to fetch more than 10 parameters from ssm parameter store programatically you will have to use multiple calls to fetch them. here the token is important , if there are more values in the path (request.withPath('/your/path/parameterName')) you have given, it will send a token indicating that there are more values in the given path ,and you will have to make the following request with the token received from the previous request in order to get the rest of the values.

Azure Document DB - Java 1.9.5 | Authorization Error

I have a collection with some documents in it. And in my application I am creating this collection first and then inserting documents. Also, based on the requirement I need to truncate (delete all documents) the collection as well. Using document db java api I have written the following code for my this purpose-
DocumentClient documentClient = getConnection(masterkey, server, portNo);
List<Database> databaseList = documentClient.queryDatabases("SELECT * FROM root r WHERE r.id='" + schemaName + "'", null).getQueryIterable().toList();
DocumentCollection collection = null;
Database databaseCache = (Database)databaseList.get(0);
List<DocumentCollection> collectionList = documentClient.queryCollections(databaseCache.getSelfLink(), "SELECT * FROM root r WHERE r.id='" + collectionName + "'", null).getQueryIterable().toList();
// truncate logic
if (collectionList.size() > 0) {
collection = ((DocumentCollection) collectionList.get(0));
if (truncate) {
try {
documentClient.deleteDocument(collection.getSelfLink(), null);
} catch (DocumentClientException e) {
e.printStackTrace();
}
}
} else { // create logic
RequestOptions requestOptions = new RequestOptions();
requestOptions.setOfferType("S1");
collection = new DocumentCollection();
collection.setId(collectionName);
try {
collection = documentClient.createCollection(databaseCache.getSelfLink(), collection, requestOptions).getResource();
} catch (DocumentClientException e) {
e.printStackTrace();
}
With the above code I am able to create a new collection successfully. Also, I am able to insert documents as well in this collection. But while truncating the collection I am getting below error-
com.microsoft.azure.documentdb.DocumentClientException: The input authorization token can't serve the request. Please check that the expected payload is built as per the protocol, and check the key being used. Server used the following payload to sign: 'delete
colls
eyckqjnw0ae=
I am using Azure Document DB Java API version 1.9.5.
It will be of great help if you can point out the error in my code or if there is any other better way of truncating collection. I would really appreciate any kind of help here.

According to your description & code, I think the issue was caused by the code below.
try {
documentClient.deleteDocument(collection.getSelfLink(), null);
} catch (DocumentClientException e) {
e.printStackTrace();
}
It seems that you want to delete a document via the code above, but pass the argument documentLink with a collection link.
So if your real intention is to delete a collection, please using the method DocumentClient.deleteCollection(collectionLink, options).

createUserDefinedFunction : if already exists?

I'm using azure-documentdb java SDK in order to create and use "User Defined Functions (UDFs)"
So from the official documentation I finally find the way (with a Java client) on how to create an UDF:
String regexUdfJson = "{"
+ "id:\"REGEX_MATCH\","
+ "body:\"function (input, pattern) { return input.match(pattern) !== null; }\","
+ "}";
UserDefinedFunction udfREGEX = new UserDefinedFunction(regexUdfJson);
getDC().createUserDefinedFunction(
myCollection.getSelfLink(),
udfREGEX,
new RequestOptions());
And here is a sample query :
SELECT * FROM root r WHERE udf.REGEX_MATCH(r.name, "mytest_.*")
I had to create the UDF one time only because I got an exception if I try to recreate an existing UDF:
DocumentClientException: Message: {"Errors":["The input name presented is already taken. Ensure to provide a unique name property for this resource type."]}
How should I do to know if the UDF already exists ?
I try to use "readUserDefinedFunctions" function without success. Any example / other ideas ?
Maybe for the long term, should we suggest a "createOrReplaceUserDefinedFunction(...)" on azure feedback

You can check for existing UDFs by running query using queryUserDefinedFunctions.
Example:
List<UserDefinedFunction> udfs = client.queryUserDefinedFunctions(
myCollection.getSelfLink(),
new SqlQuerySpec("SELECT * FROM root r WHERE r.id=#id",
new SqlParameterCollection(new SqlParameter("#id", myUdfId))),
null).getQueryIterable().toList();
if (udfs.size() > 0) {
// Found UDF.
}

An answer for .NET users.
`var collectionAltLink = documentCollections["myCollection"].AltLink; // Target collection's AltLink
var udfLink = $"{collectionAltLink}/udfs/{sampleUdfId}"; // sampleUdfId is your UDF Id
var result = await _client.ReadUserDefinedFunctionAsync(udfLink);
var resource = result.Resource;
if (resource != null)
{
// The UDF with udfId exists
}`
Here _client is Azure's DocumentClient and documentCollections is a dictionary of your documentDb collections.
If there's no such UDF in the mentioned collection, the _client throws a NotFound exception.

How to get fully materialized query from querydsl

I am trying to use querydsl for building dynamic queries for dynamic schemas. I am trying to get just the query instead of having to actually execute it.
So far I have faced two issues:
- The schema.table notation is absent. Instead I only get the table name.
- I have been able to get the query but it separates out the variables and puts '?' instead which is understandable. But I am wondering if there is some way to get fully materialized query including the parameters.
Here is my current attempt and result(I am using MySQLTemplates to create the configuration):
private SQLTemplates templates = new MySQLTemplates();
private Configuration configuration = new Configuration(templates);
String table = "sometable"
Path<Object> userPath = new PathImpl<Object>(Object.class, table);
StringPath usernamePath = Expressions.stringPath(userPath, "username");
NumberPath<Long> idPath = Expressions.numberPath(Long.class, userPath, "id");
SQLQuery sqlQuery = new SQLQuery(connection, configuration)
.from(userPath).where(idPath.eq(1l)).limit(10);
String query = sqlQuery.getSQL(usernamePath).getSQL();
return query;
And what I get is:
select sometable.username
from sometable
where sometable.id = ?
limit ?
What I wanted to get was:
select sometable.username
from someschema.sometable
where sometable.id = ?
limit ?
Update: I came up with this sort of hack to get parameters materialized(Not ideal and would love better solution) But still could not get Schema.Table notation to work:
Hack follows. Please suggest cleaner QueryDsl way of doing it:
String query = cleanQuery(sqlQuery.getSQL(usernamePath));
private String cleanQuery(SQLBindings bindings){
String query = bindings.getSQL();
for (Object binding : bindings.getBindings()) {
query = query.replaceFirst("\\?", binding.toString());
}
return query;
}

To enable schema printing use the following pattern
SQLTemplates templates = MySQLTemplates.builder()
.printSchema()
.build();
SQLTemplates subclasses were used before, but since some time the builder pattern is the official way to customize the templates http://www.querydsl.com/static/querydsl/3.3.1/reference/html/ch02s03.html#d0e904
And to enable direct serialization of literals use
//configuration level
configuration.setUseLiterals(true);
//query level
configuration.setUseLiterals(true);
Here is a full example
// configuration
SQLTemplates templates = MySQLTemplates.builder()
.printSchema()
.build();
Configuration configuration = new Configuration(templates);
// querying
SQLQuery sqlQuery = new SQLQuery(connection, configuration)
.from(userPath).where(idPath.eq(1l)).limit(10);
sqlQuery.setUseLiterals(true);
String query = sqlQuery.getSQL(usernamePath).getSQL();
If you always just want the SQL query string out, move setUseLiterals from query to configuration.
Concerning the usage of Querydsl expressions the usage of code generation like documented here is advised http://www.querydsl.com/static/querydsl/3.3.1/reference/html/ch02s03.html
It will make your code typesafe, compact and readable.
If you want to try Querydsl without code generation you can replace
Path<Object> userPath = new PathImpl<Object>(Object.class, variable);
with
Path<Object> userPath = new RelationalPathBase<Object>(Object.class, variable, schema, table);

When working with QueryDSL, you must provide a template for the database platform to build the query for. I see you are already are doing this here:
private SQLTemplates templates = new MySQLTemplates();
private Configuration configuration = new Configuration(templates);
To make the schema name appear in the generated query, the only way I have found to do this is (there may be an easier way) is to extend the template class and explicitly call this.setPrintSchema(true); inside the constructor. Here is a class that should work for MySql:
import com.mysema.query.sql.MySQLTemplates;
public class NewMySqlTemplates extends MySQLTemplates {
public NewMySqlTemplates() {
super('\\', false);
}
public NewMySqlTemplates(boolean quote) {
super('\\', quote);
}
public NewMySqlTemplates(char escape, boolean quote) {
super(escape, quote);
this.setPrintSchema(true);
}
}
Then simply use this NewMySqlTemplates class in place of the MySQLTemplates class like this:
private SQLTemplates templates = new NewMySQLTemplates();
private Configuration configuration = new Configuration(templates);
I have this working using PostgresTemplates, so I may have a typo or mistake in the NewMySqlTemplates class above, but you should be able to get it to work. Good luck!