Increment by N, return previous¶
Atomically adds the given value to the current value and returns the previous value of the counter. It is possible that multiple concurrent client requests may receive the same previous value. This occurs since only the incrementing part of the logic is atomic, the retrieval of the value before it is incremented is not.
Method:¶
PUT
Endpoint URL¶
The xxxx.backendless.app is a subdomain assigned to your application. For more information see the Client-side Setup section of this documentation.
https://xxxx.backendless.app/api/counters/<counterName>/get/incrementby?value=<value>
where:
| Argument | Description |
|---|---|
<counterName> |
Name of the counter to update. |
<value> |
Number to add to the current counter value. |
Request headers¶
user-token: optional value obtained as a result of the login operation.
where:
| Argument | Description |
|---|---|
user-token |
Optional header. Contains a value returned by Backendless in a preceding user Login API call. The operation will be executed with the security policy associated currently logged in user. This means all permissions associated with the user and the roles assigned to the user will be enforced by Backendless. |
Request body¶
N/A
Response body¶
Numeric value - previous value of the counter
Example¶
Make sure to replace xxxx in the domain name in the sample request below to the one assigned to your application.
curl -X PUT \
https://xxxx.backendless.app/api/counters/mycounter/get/incrementby?value=1000
Codeless Reference¶
where:
| Argument | Description |
|---|---|
counter name |
Name of the counter whose value must be incremented. |
increment by |
Specify the number to increment the value by. |
return previous value |
When this box is checked, the operation returns the previous value of the counter. |
Returns the previous value of the counter.
Consider the following counter:
The example below increments the value of the "CarsParkingLot" by 20. This operation returns 0, since the return previous value box is checked. To avoid confusion, the value was incremented by 20, even though the return value is 0.
The result of this operation will look as shown below after the Codeless logic runs:
