Is there a simple way to retrieve all items from a DynamoDB table using a mapping template in an API Gateway endpoint? I usually use a lambda to process the data before returning it but this is such a simple task that a Lambda seems like an overkill.
I have a table that contains data with the following format:
roleAttributeName roleHierarchyLevel roleIsActive roleName
"admin" 99 true "Admin"
"director" 90 true "Director"
"areaManager" 80 false "Area Manager"
I'm happy with getting the data, doesn't matter the representation as I can later transform it further down in my code.
I've been looking around but all tutorials explain how to get specific bits of data through queries and params like roles/{roleAttributeName} but I just want to hit roles/ and get all items.
All you need to do is
create a resource (without curly braces since we dont need a particular item)
create a get method
use Scan instead of Query in Action while configuring the integration request.
Configurations as follows :
enter image description here
now try test...you should get the response.
to try it out on postman deploy the api first and then use the provided link into postman followed by your resource name.
API Gateway allows you to Proxy DynamoDB as a service. Here you have an interesting tutorial on how to do it (you can ignore the part related to index to make it work).
To retrieve all the items from a table, you can use Scan as the action in API Gateway. Keep in mind that DynamoDB limits the query sizes to 1MB either for Scan and Query actions.
You can also limit your own query before it is automatically done by using the Limit parameter.
AWS DynamoDB Scan Reference
Related
I deleted all the items in the DataTemplate table but when I query them again with the searchDataTemplates endpoint on the app or in AppSync it returns the old data, but when I use the listDataTemplates it returns nothing which is correct. Needed to repopulate the data in the table.
data template table
search endpoint
list endpoint
when I updated items individually it worked just fine but when i deleted all the items from the console (around 700 items) the search endpoint stopped working. Just the search
UPDATE:
I repopulated the data hoping it'd reset but now the listDataTemplates shows the new data and the search still shows the old data, is there some cache that needs to be reset?
SECOND UPDATE:
I removed the table and the appsync functions are gone however when i recreated the table (with no data) the testing out the function still returns the old data. I'm guessing the opensearch stuff hasn't been updated?
If you are using AppSync with Amplify CLI, #searchable will automatically create the followings:
An OpenSearch Domain
A Lambda Function that will be attached to the DynamoDB Streams and push the changes (create/update/delete) over to your OpenSearch Domain.
And the problem that you're facing is most likely due to the Lambda Function created failed to push the changes from DynamoDB Streams to OpenSearch. A quick suggestion is to check on the created Lambda Function first.
Reference: #searchable
This issue can only happen if caching is enabled in your application.
I am not sure what's the infrastructure you are using, so i would go ahead with some educated guess. Please feel free to correct me if i overstepped.
From your description of question, you have an AppSync as API layer and DynamoDb as primary database.
If these are the only two resources you have, please check the AppSync cache configuration.
Open AppSync console
from left panel select APIs -> your api -> caching
Validate Caching behavior is set to None
In case if you have AWS OpenSearch enabled for search query (i could be wrong, however picking up from previous comment). Then validate the cluster configuration.
Open AWS Open Search Service console
From left panel select Domains and click on the openserch domain that you are using
scroll to the bottom right and look for Advanced cluster settings and ensure the attribute Fielddata cache allocation is set to 0
If Fielddata cache allocation is not 0, update the cluster configuration and modify the advanced cluster setting to set the Fielddata cache allocation field to 0.
Wait for a few minutes (I would suggest 5 minutes) and then retry your use-case.
I hope this would help resolve your issue.
I am using AWS proxy with AWS API Gateway to interact with a DynamoDB table. I have an API resource, under which I have a GET method with the below configuration:
The API uses the Scan action as seen above to fetch all the items from the DynamoDB table. I also have the following request integration mapping template;
{
"TableName": tableName
}
Its really simple. But my problem is that I would like to add another GET method to get each item by their id, which will be supplied in the URL as a param. However, since I have already setup one GET method, I am not able to setup another to fetch only a single item. I am aware I can use mapping templates and Scan as given in the docs to conditionally fetch items if a param is given, but that would mean scanning the entire table, which is a waste each time I want to fetch a single item.
Is there any other way to do this?
I am quite new to the CDK, but I'm adding a LogQueryWidget to my CloudWatch Dashboard through the CDK, and I need a way to add all LogGroups ending with a suffix to the query.
Is there a way to either loop through all existing LogGroups and finding the ones with the correct suffix, or a way to search through LogGroups.
const queryWidget = new LogQueryWidget({
title: "Error Rate",
logGroupNames: ['/aws/lambda/someLogGroup'],
view: LogQueryVisualizationType.TABLE,
queryLines: [
'fields #message',
'filter #message like /(?i)error/'
],
})
Is there anyway I can add it so logGroupNames contains all LogGroups that end with a specific suffix?
You cannot do that dynamically (i.e. you can't make this work such that if you add a new LogGroup, the query automatically adjusts), without using something like AWS lambda that periodically updates your Log Query.
However, because CDK is just a code, there is nothing stopping you from making an AWS SDK API call inside the code to retrieve all the log groups (See https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/CloudWatchLogs.html#describeLogGroups-property) and then populate logGroupNames accordingly.
That way, when CDK compiles, it will make an API call to fetch LogGroups and then generated CloudFormation will contain the log groups you need. Note that this list will only be updated when you re-synthesize and re-deploy your stack.
Finally, note that there is a limit on how many Log Groups you can query with Log Insights (20 according to https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/AnalyzingLogData.html).
If you want to achieve this, you can create a custom resource using AwsCustomResource and AwsSdkCall classes to do the AWS SDK API call (as mentioned by #Tofig above) as part of the deployment. You can read data from the API call response as well and act on it as you want.
Simple question, but I suspect it doesn't have a simple or easy answer. Still, worth asking.
We're creating an implementation for push notifications using AWS with our Web Server running on EC2, sending messages to a queue on SQS, which is dealt with using Lambda, which is sent finally to SNS to be delivered to the iOS/Android apps.
The question I have is this: is there a way to query SNS endpoints based on the custom user data that you can provide on creation? The only way I see to do this so far is to list all the endpoints in a given platform application, and then search through that list for the user data I'm looking for... however, a more direct approach would be far better.
Why I want to do this is simple: if I could attach a User Identifier to these Device Endpoints, and query based on that, I could avoid completely having to save the ARN to our DynamoDB database. It would save a lot of implementation time and complexity.
Let me know what you guys think, even if what you think is that this idea is impractical and stupid, or if searching through all of them is the best way to go about this!
Cheers!
There isn't the ability to have a "where" clause in ListTopics. I see two possibilities:
Create a new SNS topic per user that has some identifiable id in it. So, for example, the ARN would be something like "arn:aws:sns:us-east-1:123456789:know-prefix-user-id". The obvious downside is that you have the potential for a boat load of SNS topics.
Use a service designed for this type of usage like PubNub. Disclaimer - I don't work for PubNub or own stock but have successfully used it in multiple projects. You'll be able to target one or many users this way.
According the the [AWS documentation][1] if you try and create a new Platform Endpoint with the same User Data you should get a response with an exception including the ARN associated with the existing PlatformEndpoint.
It's definitely not ideal, but it would be a round about way of querying the User Data Endpoint attributes via exception.
//Query CustomUserData by exception
CreatePlatformEndpointRequest cpeReq = new CreatePlatformEndpointRequest().withPlatformApplicationArn(applicationArn).withToken("dummyToken").withCustomUserData("username");
CreatePlatformEndpointResult cpeRes = client.createPlatformEndpoint(cpeReq);
You should get an exception with the ARN if an endpoint with the same withCustomUserData exists.
Then you just use that ARN and away you go.
I'm a newbie rails programmer, and I have even less experience with all the AWS products. I'm trying to use lambda to subscribe to and consume an rss feed from youtube. I am able to send the subscription request just fine with HTTParty from my locally hosted rails app:
query = {'hub.mode':'subscribe', 'hub.verify':'sync', 'hub.topic': 'https://www.youtube.com/feeds/videos.xml?channel_id=CHANNELID', 'hub.callback':'API Endpoint for Lambda'}
subscribe = 'HTTParty.post(https://pubsubhubbub.appspot.com/subscribe, :query=>query)
and it will ping the lambda function with a get request. I know that I need to echo back a hub.challenge string, but I don't know how. The lambda event is empty, I didn't see anything useful in the context. I tried formatting the response in the API gateway but that didn't work either. So right now when I try to subscribe I get back a 'Challenge Mismatch' error.
I know this: https://pubsubhubbub.googlecode.come/git/pubsubhubbub-core-0.3.html#subscribing explains what I'm trying to do better than what I just did, and section 6.2.1 is where the breakdown is. How do I set up either the AWS Lambda function and/or the API Gateway to reflect back the 'hub.challenge' verification token string?
You need to use the parameter mapping functionality of API Gateway to map the parameters from the incoming query string to a parameter passed to your Lambda function. From the documentation link you provided, it looks like you'll at least need to map the hub.challenge query string parameter, but you may also need the other parameters (hub.mode, hub.topic, and hub.verify_token) depending on what validation logic (if any) that you're implementing.
The first step is to declare your query string parameters in the method request page. Once you have declared the parameters open the integration request page (where you specify which Lambda function API Gateway should call) and use the "+" icon to add a new template. In the template you will have to specify a content type (application/json), and then the body you want to send to Lambda. You can read both query string and header parameters using the params() function. In that input mapping field you are creating the event body that is posted to AWS Lambda. For example: { "challenge": "$input.params('hub.challenge')" }
Documentation for mapping query string parameters