title | description |
---|---|
Idempotency |
Utility |
???+ warning
This utility is currently in developer preview and is intended strictly for feedback and testing purposes and not for production workloads. The version and all future versions tagged with the -preview
suffix should be treated as not stable. Until this utility is General Availability we may introduce significant breaking changes and improvements in response to customers feedback.
The idempotency utility provides a simple solution to convert your Lambda functions into idempotent operations which are safe to retry.
- Prevent Lambda handler function from executing more than once on the same event payload during a time window
- Ensure Lambda handler returns the same result when called with the same payload
- Select a subset of the event as the idempotency key using JMESPath expressions
- Set a time window in which records with the same payload should be considered duplicates
- Expires in-progress executions if the Lambda function times out halfway through
The property of idempotency means that an operation does not cause additional side effects if it is called more than once with the same input parameters.
Idempotent operations will return the same result when they are called multiple times with the same parameters. This makes idempotent operations safe to retry. Read more about idempotency.
Idempotency key is a hash representation of either the entire event or a specific configured subset of the event, and invocation results are JSON serialized and stored in your persistence storage layer.
Idempotency record is the data representation of an idempotent request saved in your preferred storage layer. We use it to coordinate whether a request is idempotent, whether it's still valid or expired based on timestamps, etc.
You should install with NuGet:
Install-Package AWS.Lambda.Powertools.Idempotency
Or via the .NET Core command line interface:
dotnet add package AWS.Lambda.Powertools.Idempotency
Your Lambda function IAM Role must have dynamodb:GetItem
, dynamodb:PutItem
, dynamodb:UpdateItem
and dynamodb:DeleteItem
IAM permissions before using this feature.
???+ note If you're using our example AWS Serverless Application Model (SAM), AWS Cloud Development Kit (CDK), or Terraform it already adds the required permissions.
Before getting started, you need to create a persistent storage layer where the idempotency utility can store its state - your Lambda functions will need read and write access to it.
As of now, Amazon DynamoDB is the only supported persistent storage layer, so you'll need to create a table first.
Default table configuration
If you're not changing the default configuration for the DynamoDB persistence layer, this is the expected default configuration:
Configuration | Value | Notes |
---|---|---|
Partition key | id |
|
TTL attribute name | expiration |
This can only be configured after your table is created if you're using AWS Console |
!!! Tip "Tip: You can share a single state table for all functions" You can reuse the same DynamoDB table to store idempotency state. We add your function name in addition to the idempotency key as a hash key.
=== "template.yml"
```yaml hl_lines="5-13 21-23 26" title="AWS Serverless Application Model (SAM) example"
Resources:
IdempotencyTable:
Type: AWS::DynamoDB::Table
Properties:
AttributeDefinitions:
- AttributeName: id
AttributeType: S
KeySchema:
- AttributeName: id
KeyType: HASH
TimeToLiveSpecification:
AttributeName: expiration
Enabled: true
BillingMode: PAY_PER_REQUEST
IdempotencyFunction:
Type: AWS::Serverless::Function
Properties:
CodeUri: Function
Handler: HelloWorld::HelloWorld.Function::FunctionHandler
Policies:
- DynamoDBCrudPolicy:
TableName: !Ref IdempotencyTable
Environment:
Variables:
IDEMPOTENCY_TABLE: !Ref IdempotencyTable
```
!!! warning "Warning: Large responses with DynamoDB persistence layer" When using this utility with DynamoDB, your function's responses must be smaller than 400KB. Larger items cannot be written to DynamoDB and will cause exceptions.
!!! info "Info: DynamoDB" Each function invocation will generally make 2 requests to DynamoDB. If the result returned by your Lambda is less than 1kb, you can expect 2 WCUs per invocation. For retried invocations, you will see 1WCU and 1RCU. Review the DynamoDB pricing documentation to estimate the cost.
You can quickly start by configuring Idempotency
and using it with the Idempotent
attribute on your Lambda function.
!!! warning "Important"
Initialization and configuration of the Idempotency
must be performed outside the handler, preferably in the constructor.
```csharp hl_lines="4 7"
public class Function
{
public Function()
{
Idempotency.Configure(builder => builder.UseDynamoDb("idempotency_table"));
}
[Idempotent]
public Task<string> FunctionHandler(string input, ILambdaContext context)
{
return Task.FromResult(input.ToUpper());
}
}
```
You can use the Idempotent
attribute for any .NET function, not only the Lambda handlers.
When using Idempotent
attribute on another method, you must tell which parameter in the method signature has the data we should use:
- If the method only has one parameter, it will be used by default.
- If there are 2 or more parameters, you must set the
IdempotencyKey
attribute on the parameter to use.
!!! info "The parameter must be serializable in JSON. We use System.Text.Json
internally to (de)serialize objects"
```csharp hl_lines="4 13-14"
public class Function
{
public Function()
{
Idempotency.Configure(builder => builder.UseDynamoDb("idempotency_table"));
}
public Task<string> FunctionHandler(string input, ILambdaContext context)
{
MyInternalMethod("hello", "world")
return Task.FromResult(input.ToUpper());
}
[Idempotent]
private string MyInternalMethod(string argOne, [IdempotencyKey] string argTwo) {
return "something";
}
}
```
!!! tip "Tip: Dealing with always changing payloads"
When dealing with an elaborate payload (API Gateway request for example), where parts of the payload always change, you should configure the EventKeyJmesPath
.
Use IdempotencyConfig
to instruct the Idempotent annotation to only use a portion of your payload to verify whether a request is idempotent, and therefore it should not be retried.
Payment scenario
In this example, we have a Lambda handler that creates a payment for a user subscribing to a product. We want to ensure that we don't accidentally charge our customer by subscribing them more than once.
Imagine the function executes successfully, but the client never receives the response due to a connection issue. It is safe to retry in this instance, as the idempotent decorator will return a previously saved response.
What we want here is to instruct Idempotency to use user_id
and product_id
fields from our incoming payload as our idempotency key.
If we were to treat the entire request as our idempotency key, a simple HTTP header change would cause our customer to be charged twice.
???+ tip "Deserializing JSON strings in payloads for increased accuracy."
The payload extracted by the EventKeyJmesPath
is treated as a string by default, so will be sensitive to differences in whitespace even when the JSON payload itself is identical.
To alter this behaviour, you can use the JMESPath built-in function `powertools_json()` to treat the payload as a JSON object rather than a string.
=== "Payment function"
```csharp hl_lines="3"
Idempotency.Configure(builder =>
builder
.WithOptions(optionsBuilder =>
optionsBuilder.WithEventKeyJmesPath("powertools_json(Body).[\"user_id\", \"product_id\"]"))
.UseDynamoDb("idempotency_table"));
```
=== "Sample event"
```json hl_lines="27"
{
"version": "2.0",
"routeKey": "ANY /createpayment",
"rawPath": "/createpayment",
"rawQueryString": "",
"headers": {
"Header1": "value1",
"Header2": "value2"
},
"requestContext": {
"accountId": "123456789012",
"apiId": "api-id",
"domainName": "id.execute-api.us-east-1.amazonaws.com",
"domainPrefix": "id",
"http": {
"method": "POST",
"path": "/createpayment",
"protocol": "HTTP/1.1",
"sourceIp": "ip",
"userAgent": "agent"
},
"requestId": "id",
"routeKey": "ANY /createpayment",
"stage": "$default",
"time": "10/Feb/2021:13:40:43 +0000",
"timeEpoch": 1612964443723
},
"body": "{\"user_id\":\"xyz\",\"product_id\":\"123456789\"}",
"isBase64Encoded": false
}
```
???+ note This is automatically done when you decorate your Lambda handler with Idempotent attribute.
To prevent against extended failed retries when a Lambda function times out{target="_blank"}, Powertools for AWS Lambda (.NET) calculates and includes the remaining invocation available time as part of the idempotency record.
???+ example
If a second invocation happens after this timestamp, and the record is marked as INPROGRESS
, we will execute the invocation again as if it was in the EXPIRED
state (e.g, Expired
field elapsed).
This means that if an invocation expired during execution, it will be quickly executed again on the next retry.
???+ important
If you are only using the Idempotent attribute to guard isolated parts of your code,
you must use RegisterLambdaContext
available in the Idempotency
static class to benefit from this protection.
Here is an example on how you register the Lambda context in your handler:
=== "Registering the Lambda context"
```csharp hl_lines="9" title="Registering the Lambda context"
public class Function
{
public Function()
{
Idempotency.Configure(builder => builder.UseDynamoDb("idempotency_table"));
}
public Task<string> FunctionHandler(string input, ILambdaContext context)
{
Idempotency.RegisterLambdaContext(context);
MyInternalMethod("hello", "world")
return Task.FromResult(input.ToUpper());
}
[Idempotent]
private string MyInternalMethod(string argOne, [IdempotencyKey] string argTwo) {
return "something";
}
}
```
If you are using the Idempotent
attribute on your Lambda handler or any other method, any unhandled exceptions that are thrown during the code execution will cause the record in the persistence layer to be deleted.
This means that new invocations will execute your code again despite having the same payload. If you don't want the record to be deleted, you need to catch exceptions within the idempotent function and return a successful response.
!!! warning
We will throw an IdempotencyPersistenceLayerException
if any of the calls to the persistence layer fail unexpectedly.
As this happens outside the scope of your decorated function, you are not able to catch it.
Lambda invocations with the same
payload running concurrently. Lambda--xLambda: Call handler (event).
Raises exception Lambda->>Persistence Layer: Delete record (id=event.search(payload)) deactivate Persistence Layer Lambda-->>Client: Return error response ``` Idempotent sequence exception
If you are using Idempotent
attribute on another method, any unhandled exceptions that are raised inside the decorated function will cause the record in the persistence layer to be deleted, and allow the function to be executed again if retried.
If an Exception is raised outside the scope of the decorated method and after your method has been called, the persistent record will not be affected. In this case, idempotency will be maintained for your decorated function. Example:
=== "Handling exceptions"
```csharp hl_lines="2-4 8-10" title="Exception not affecting idempotency record sample"
public class Function
{
public Function()
{
Idempotency.Configure(builder => builder.UseDynamoDb("idempotency_table"));
}
public Task<string> FunctionHandler(string input, ILambdaContext context)
{
Idempotency.RegisterLambdaContext(context);
// If an exception is thrown here, no idempotent record will ever get created as the
// idempotent method does not get called
MyInternalMethod("hello", "world")
// This exception will not cause the idempotent record to be deleted, since it
// happens after the decorated method has been successfully called
throw new Exception();
}
[Idempotent]
private string MyInternalMethod(string argOne, [IdempotencyKey] string argTwo) {
return "something";
}
}
```
The following sequence diagrams explain how the Idempotency feature behaves under different scenarios.
```mermaid sequenceDiagram participant Client participant Lambda participant Persistence Layer alt initial request Client->>Lambda: Invoke (event) Lambda->>Persistence Layer: Get or set idempotency_key=hash(payload) activate Persistence Layer Note over Lambda,Persistence Layer: Set record status to INPROGRESS.Prevents concurrent invocations
with the same payload Lambda-->>Lambda: Call your function Lambda->>Persistence Layer: Update record with result deactivate Persistence Layer Persistence Layer-->>Persistence Layer: Update record Note over Lambda,Persistence Layer: Set record status to COMPLETE.
New invocations with the same payload
now return the same result Lambda-->>Client: Response sent to client else retried request Client->>Lambda: Invoke (event) Lambda->>Persistence Layer: Get or set idempotency_key=hash(payload) activate Persistence Layer Persistence Layer-->>Lambda: Already exists in persistence layer. deactivate Persistence Layer Note over Lambda,Persistence Layer: Record status is COMPLETE and not expired Lambda-->>Client: Same response sent to client end ``` Idempotent successful request
!!! note "In-memory cache is disabled by default."
```mermaid sequenceDiagram participant Client participant Lambda participant Persistence Layer alt initial request Client->>Lambda: Invoke (event) Lambda->>Persistence Layer: Get or set idempotency_key=hash(payload) activate Persistence Layer Note over Lambda,Persistence Layer: Set record status to INPROGRESS.Prevents concurrent invocations
with the same payload Lambda-->>Lambda: Call your function Lambda->>Persistence Layer: Update record with result deactivate Persistence Layer Persistence Layer-->>Persistence Layer: Update record Note over Lambda,Persistence Layer: Set record status to COMPLETE.
New invocations with the same payload
now return the same result Lambda-->>Lambda: Save record and result in memory Lambda-->>Client: Response sent to client else retried request Client->>Lambda: Invoke (event) Lambda-->>Lambda: Get idempotency_key=hash(payload) Note over Lambda,Persistence Layer: Record status is COMPLETE and not expired Lambda-->>Client: Same response sent to client end ``` Idempotent successful request cached ```mermaid sequenceDiagram participant Client participant Lambda participant Persistence Layer alt initial request Client->>Lambda: Invoke (event) Lambda->>Persistence Layer: Get or set idempotency_key=hash(payload) activate Persistence Layer Note over Lambda,Persistence Layer: Set record status to INPROGRESS.
Prevents concurrent invocations
with the same payload Lambda-->>Lambda: Call your function Lambda->>Persistence Layer: Update record with result deactivate Persistence Layer Persistence Layer-->>Persistence Layer: Update record Note over Lambda,Persistence Layer: Set record status to COMPLETE.
New invocations with the same payload
now return the same result Lambda-->>Client: Response sent to client else retried request Client->>Lambda: Invoke (event) Lambda->>Persistence Layer: Get or set idempotency_key=hash(payload) activate Persistence Layer Persistence Layer-->>Lambda: Already exists in persistence layer. deactivate Persistence Layer Note over Lambda,Persistence Layer: Record status is COMPLETE but expired hours ago loop Repeat initial request process Note over Lambda,Persistence Layer: 1. Set record to INPROGRESS,
2. Call your function,
3. Set record to COMPLETE end Lambda-->>Client: Same response sent to client end ``` Previous Idempotent request expired ```mermaid sequenceDiagram participant Client participant Lambda participant Persistence Layer Client->>Lambda: Invoke (event) Lambda->>Persistence Layer: Get or set idempotency_key=hash(payload) activate Persistence Layer Note over Lambda,Persistence Layer: Set record status to INPROGRESS.
Prevents concurrent invocations
with the same payload par Second request Client->>Lambda: Invoke (event) Lambda->>Persistence Layer: Get or set idempotency_key=hash(payload) Lambda--xLambda: IdempotencyAlreadyInProgressError Lambda->>Client: Error sent to client if unhandled end Lambda-->>Lambda: Call your function Lambda->>Persistence Layer: Update record with result deactivate Persistence Layer Persistence Layer-->>Persistence Layer: Update record Note over Lambda,Persistence Layer: Set record status to COMPLETE.
New invocations with the same payload
now return the same result Lambda-->>Client: Response sent to client ``` Concurrent identical in-flight requests ```mermaid sequenceDiagram participant Client participant Lambda participant Persistence Layer alt initial request Client->>Lambda: Invoke (event) Lambda->>Persistence Layer: Get or set idempotency_key=hash(payload) activate Persistence Layer Note over Lambda,Persistence Layer: Set record status to INPROGRESS.
Prevents concurrent invocations
with the same payload Lambda-->>Lambda: Call your function Note right of Lambda: Time out Lambda--xLambda: Time out error Lambda-->>Client: Return error response deactivate Persistence Layer else retry after Lambda timeout elapses Client->>Lambda: Invoke (event) Lambda->>Persistence Layer: Get or set idempotency_key=hash(payload) activate Persistence Layer Note over Lambda,Persistence Layer: Set record status to INPROGRESS.
Reset in_progress_expiry attribute Lambda-->>Lambda: Call your function Lambda->>Persistence Layer: Update record with result deactivate Persistence Layer Persistence Layer-->>Persistence Layer: Update record Lambda-->>Client: Response sent to client end ``` Idempotent request during and after Lambda timeouts ```mermaid sequenceDiagram participant Client participant Lambda participant Persistence Layer alt request with idempotency key Client->>Lambda: Invoke (event) Lambda->>Persistence Layer: Get or set idempotency_key=hash(payload) activate Persistence Layer Note over Lambda,Persistence Layer: Set record status to INPROGRESS.
Prevents concurrent invocations
with the same payload Lambda-->>Lambda: Call your function Lambda->>Persistence Layer: Update record with result deactivate Persistence Layer Persistence Layer-->>Persistence Layer: Update record Note over Lambda,Persistence Layer: Set record status to COMPLETE.
New invocations with the same payload
now return the same result Lambda-->>Client: Response sent to client else request(s) without idempotency key Client->>Lambda: Invoke (event) Note over Lambda: Idempotency key is missing Note over Persistence Layer: Skips any operation to fetch, update, and delete Lambda-->>Lambda: Call your function Lambda-->>Client: Response sent to client end ``` Optional idempotency key
This persistence store is built-in, and you can either use an existing DynamoDB table or create a new one dedicated for idempotency state (recommended).
Use the builder to customize the table structure:
new DynamoDBPersistenceStoreBuilder()
.WithTableName("TABLE_NAME")
.WithKeyAttr("idempotency_key")
.WithExpiryAttr("expires_at")
.WithStatusAttr("current_status")
.WithDataAttr("result_data")
.WithValidationAttr("validation_key")
.WithInProgressExpiryAttr("in_progress_expires_at")
.Build()
When using DynamoDB as a persistence layer, you can alter the attribute names by passing these parameters when initializing the persistence layer:
Parameter | Required | Default | Description |
---|---|---|---|
TableName | Y | Table name to store state | |
KeyAttr | id |
Partition key of the table. Hashed representation of the payload (unless SortKeyAttr is specified) | |
ExpiryAttr | expiration |
Unix timestamp of when record expires | |
InProgressExpiryAttr | in_progress_expiration |
Unix timestamp of when record expires while in progress (in case of the invocation times out) | |
StatusAttr | status |
Stores status of the Lambda execution during and after invocation | |
DataAttr | data |
Stores results of successfully idempotent methods | |
ValidationAttr | validation |
Hashed representation of the parts of the event used for validation | |
SortKeyAttr | Sort key of the table (if table is configured with a sort key). | ||
StaticPkValue | idempotency#{LAMBDA_FUNCTION_NAME} |
Static value to use as the partition key. Only used when SortKeyAttr is set. |
Idempotency behavior can be further configured with IdempotencyOptions
using a builder:
new IdempotencyOptionsBuilder()
.WithEventKeyJmesPath("id")
.WithPayloadValidationJmesPath("paymentId")
.WithThrowOnNoIdempotencyKey(true)
.WithExpiration(TimeSpan.FromMinutes(1))
.WithUseLocalCache(true)
.WithHashFunction("MD5")
.Build();
These are the available options for further configuration:
Parameter | Default | Description |
---|---|---|
EventKeyJMESPath | "" |
JMESPath expression to extract the idempotency key from the event record. |
PayloadValidationJMESPath | "" |
JMESPath expression to validate whether certain parameters have changed in the event |
ThrowOnNoIdempotencyKey | False |
Throw exception if no idempotency key was found in the request |
ExpirationInSeconds | 3600 | The number of seconds to wait before a record is expired |
UseLocalCache | false |
Whether to locally cache idempotency results (LRU cache) |
HashFunction | MD5 |
Algorithm to use for calculating hashes, as supported by System.Security.Cryptography.HashAlgorithm (eg. SHA1, SHA-256, ...) |
These features are detailed below.
This utility will throw an IdempotencyAlreadyInProgressException
if we receive multiple invocations with the same payload while the first invocation hasn't completed yet.
!!! info
If you receive IdempotencyAlreadyInProgressException
, you can safely retry the operation.
This is a locking mechanism for correctness. Since we don't know the result from the first invocation yet, we can't safely allow another concurrent execution.
By default, in-memory local caching is disabled, to avoid using memory in an unpredictable way.
!!! warning Memory configuration of your function Be sure to configure the Lambda memory according to the number of records and the potential size of each record.
You can enable it as seen before with:
new IdempotencyOptionsBuilder()
.WithUseLocalCache(true)
.Build()
When enabled, we cache a maximum of 255 records in each Lambda execution environment
!!! note "Note: This in-memory cache is local to each Lambda execution environment" This means it will be effective in cases where your function's concurrency is low in comparison to the number of "retry" invocations with the same payload, because cache might be empty.
!!! note By default, we expire idempotency records after an hour (3600 seconds).
In most cases, it is not desirable to store the idempotency records forever. Rather, you want to guarantee that the same payload won't be executed within a period of time.
You can change this window with the ExpirationInSeconds
parameter:
new IdempotencyOptionsBuilder()
.WithExpiration(TimeSpan.FromMinutes(5))
.Build()
Records older than 5 minutes will be marked as expired, and the Lambda handler will be executed normally even if it is invoked with a matching payload.
!!! note "Note: DynamoDB time-to-live field"
This utility uses expiration
as the TTL field in DynamoDB, as demonstrated in the SAM example earlier.
!!! question "Question: What if your function is invoked with the same payload except some outer parameters have changed?" Example: A payment transaction for a given productID was requested twice for the same customer, however the amount to be paid has changed in the second transaction.
By default, we will return the same result as it returned before, however in this instance it may be misleading; we provide a fail fast payload validation to address this edge case.
With PayloadValidationJMESPath
, you can provide an additional JMESPath expression to specify which part of the event body should be validated against previous idempotent invocations
=== "Function.cs"
```csharp
Idempotency.Configure(builder =>
builder
.WithOptions(optionsBuilder =>
optionsBuilder
.WithEventKeyJmesPath("[userDetail, productId]")
.WithPayloadValidationJmesPath("amount"))
.UseDynamoDb("TABLE_NAME"));
```
=== "Example Event 1"
```json hl_lines="8"
{
"userDetail": {
"username": "User1",
"user_email": "[email protected]"
},
"productId": 1500,
"charge_type": "subscription",
"amount": 500
}
```
=== "Example Event 2"
```json hl_lines="8"
{
"userDetail": {
"username": "User1",
"user_email": "[email protected]"
},
"productId": 1500,
"charge_type": "subscription",
"amount": 1
}
```
In this example, the userDetail
and productId
keys are used as the payload to generate the idempotency key, as per EventKeyJMESPath
parameter.
!!! note
If we try to send the same request but with a different amount, we will raise IdempotencyValidationException
.
Without payload validation, we would have returned the same result as we did for the initial request. Since we're also returning an amount in the response, this could be quite confusing for the client.
By using withPayloadValidationJMESPath("amount")
, we prevent this potentially confusing behavior and instead throw an Exception.
If you want to enforce that an idempotency key is required, you can set ThrowOnNoIdempotencyKey
to True
.
This means that we will throw IdempotencyKeyException
if the evaluation of EventKeyJMESPath
is null
.
=== "Function.cs"
```csharp
public App()
{
Idempotency.Configure(builder =>
builder
.WithOptions(optionsBuilder =>
optionsBuilder
// Requires "user"."uid" and "orderId" to be present
.WithEventKeyJmesPath("[user.uid, orderId]")
.WithThrowOnNoIdempotencyKey(true))
.UseDynamoDb("TABLE_NAME"));
}
[Idempotent]
public Task<OrderResult> FunctionHandler(Order input, ILambdaContext context)
{
// ...
}
```
=== "Success Event"
```json
{
"user": {
"uid": "BB0D045C-8878-40C8-889E-38B3CB0A61B1",
"name": "Foo"
},
"orderId": 10000
}
```
=== "Failure Event"
Notice that `orderId` is now accidentally within `user` key
```json
{
"user": {
"uid": "DE0D000E-1234-10D1-991E-EAC1DD1D52C8",
"name": "Joe Bloggs",
"orderId": 10000
},
}
```
When creating the DynamoDBPersistenceStore
, you can set a custom AmazonDynamoDBClient
if you need to customize the configuration:
=== "Custom AmazonDynamoDBClient"
```csharp
public Function()
{
AmazonDynamoDBClient customClient = new AmazonDynamoDBClient(RegionEndpoint.APSouth1);
Idempotency.Configure(builder =>
builder.UseDynamoDb(storeBuilder =>
storeBuilder.
WithTableName("TABLE_NAME")
.WithDynamoDBClient(customClient)
));
}
```
When using a composite primary key table (hash+range key), use SortKeyAttr
parameter when initializing your persistence store.
With this setting, we will save the idempotency key in the sort key instead of the primary key. By default, the primary key will now be set to idempotency#{LAMBDA_FUNCTION_NAME}
.
You can optionally set a static value for the partition key using the StaticPkValue
parameter.
Idempotency.Configure(builder =>
builder.UseDynamoDb(storeBuilder =>
storeBuilder.
WithTableName("TABLE_NAME")
.WithSortKeyAttr("sort_key")
));
Data would then be stored in DynamoDB like this:
id | sort_key | expiration | status | data |
---|---|---|---|---|
idempotency#MyLambdaFunction | 1e956ef7da78d0cb890be999aecc0c9e | 1636549553 | COMPLETED | {"id": 12391, "message": "success"} |
idempotency#MyLambdaFunction | 2b2cdb5f86361e97b4383087c1ffdf27 | 1636549571 | COMPLETED | {"id": 527212, "message": "success"} |
idempotency#MyLambdaFunction | f091d2527ad1c78f05d54cc3f363be80 | 1636549585 | IN_PROGRESS |
The idempotency utility provides several routes to test your code.
When testing your code, you may wish to disable the idempotency logic altogether and focus on testing your business logic. To do this, you can set the environment variable POWERTOOLS_IDEMPOTENCY_DISABLED
to true.
If you're interested in a deep dive on how Amazon uses idempotency when building our APIs, check out this article.