Is it possible to validate queryparam with no value using Apigee Conditional Statements in request uri ?

Google Cloud Apigee
1

I would like to check whether a queryparam exist or not in request uri.

For example how can i validate a queryparam ‘company’ exists or not in below request uri using apigee conditional statement ?

[http://www.example.com?name=anil&company](http://www.example.com?name=anil&company)

PS: One way is to use regular expression, other way is to use javascript policy.

Is it possible to validate this using variable and conditional operators ?

Cheers,

Anil Sagar

2

One option is to use the AssignMessage policy to assign a default value to the query param if the value is omitted:

<AssignMessage async="false" continueOnError="false" enabled="true" name="DefaultWQP">
  <AssignTo createNew="false" transport="http" type="request"/>
  <IgnoreUnresolvedVariables>true</IgnoreUnresolvedVariables>
  <AssignVariable> 
    <Name>request.queryparam.company</Name>
    <Ref>request.queryparam.comapny</Ref> 
    <Value>Apigee</Value>
  </AssignVariable> 
</AssignMessage>
3

@sgilson

, Does above policy executes even if key is not present ? Ideally i would like to detect whether a key exists without a value. Something like check variable is defined or not even though it doesn’t have any value

4

@Anil Sagar - request.queryparam.company will give you null if query parameter’s value is empty (perhaps a bug in the product).

However you will get the existence of the queryparam using request.queryparams.names. It will give you an array which contains [company]

1 Like
5

Thank you @Ozan Seymen… I just thought the same. Hopefully it will be fixed in next few releases if that’s the case.

6

It does. You could set the default value to something no one would enter, like “xxxyyyzzz”, and then check request.queryparam.comapny against that value.

7

@sgilson - in this scenario, your assign message will always override as request.queryparam.company will always be null.

A queryparam variable value will always be null unless it has a value.

1 Like
8

Right - I was saying that this will set the query param to “xxxyyyzzz” only when the query param is null. If the user passes a value for it in the request, then the query param will be set as specified by the user.

9

This will set the query param to “xxxyyyzzz” successfully in two different cases which Anil is trying to distinguish between:

api.com

api.com?company

He is trying to understand whether company parameter exists or not.

10

The following tests for values in a queryparam and raises a fault only if the value is null - essentially executing the raiseFault policy if the queryparam were omitted:

<Step>
	<Name>raiseBadRequest</Name>
	<Condition>request.queryparam.limit==null</Condition>
</Step>

This can be inverted to execute a policy if the value were defined (!=null).