Cache assertion and Lookup in Cache policy example

Products

• CA API Gateway

Issue/Introduction

The "cachesample" policy only pretend to show as example how the cache works, save and retrieve values using cache assertion.

Environment

CA API Gateway 10.x , 11.x

Cause

Customer requiring example to understand how to use the cache assertion. Due during the testing is not collecting values as expected

Resolution

1. the policy sent only pretend to show as example how to cache works, save and retrieve values using cache assertion.

when hitting the call#1 and/or Call#2, I'm showing the token value all time, so this is "educational" , the token value will appears as output all the time

When using the lookup assertion  , has set "maximum acceptable age"=300 seconds

Also , note the following , for Cache Storage properties , the following values has been set :
Maximum entries = 10
Maximum Entry Age (seconds)= 300 
Maximum entry Bytes =1000

*** All above is located at the line#12 on sample policy  

So, if you are using this calls after 5 mins , you will not have the expected values returning.

Specify the maximum acceptable age (in seconds) of a cached item.

If an item is below this age, it will be retrieved from the cache and returned in the response.

If the cached item exceeds this age, it will not be retrieved. You may reference context variables.

The default is 300 seconds

 

Ref: Look up in cache assertion

 

2. How to use the Policy Example on a call  :

Call#1 https://GwName.domain.com:8443/cachesample?token=111&var=Stored/Cached
token: 111
Value: Stored/Cached
action: 
exists: Storing
Response: 

The first call has a Value, to be cached (Stored/Cached)

the second call has a Response, which is the value cached on call#1...

call#2 : https://GwName.domain.com:8443/cachesample?token=111&lookup=true
token: 111
Value: 
action: true
exists: true
Response: Stored/Cached

On the call#2 , the Action and Exist=true (both), and the Response=Stored/Cached, this means the value 111 is cached.

3. if you use the call#2 again but changes the value to 333 and that value was not cached before with the call#1 will show this

https://GwName.domain.com:8443/cachesample?token=333&lookup=true

token: 333
Value: 
action: true
exists: Storing
Response:

there is not response value here, means the 333 has not been cached or was already deleted from cache(passed 300 seconds).

4. However  if using a new call like :

https://GwName.domain.com:8443/cachesample?token=444&var=Saved444

Results will be :

token: 444
Value: Saved444
action: 
exists: Storing
Response: 

And then  looking for the token 4444, but the value cached was using var "Saved444" 

https://GwName.domain.com:8443/cachesample?token=444&lookup=true

token: 444
Value: 
action: true
exists: true
Response: Saved444

Note : If do you need help to create a more sophisticated or complex policy you would to contact Broadcom Services Team or partner to help on that purpose