Extract response headers with same header name

[Aravind]

Hi Everybody! 

I am using service callout policy to get the CSRF token and also getting some response headers.

From response headers, am trying to extract header set-cookie but have two set-cookie headers with same header name.

Example:

Response headers:

set-cookie: abc

set-cookie:123

I am using variable calloutresponse.header.set-cookie but it was extracting value abc but I want to extract the value 123. please let me know the solution.

Thanks in advance!

[Giupo · Accepted solution]

Hello,
I have faced this problem for several days, I will try to provide you with as many details as possible so as to help other readers as well.

First of all, I would like to point out that by making a no-route example proxy and adding a policy that adds two "set-cookie" headers in request, you will be able to see in the debug that Apigee merges the two headers.

This is the policy:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<AssignMessage continueOnError="false" enabled="true" name="AM_set-cookie">
  <DisplayName>AM_set-cookie</DisplayName>
  <Properties/>
  <Add>
    <Headers>
      <Header name="set-cookie">firstcookie=ABCDE</Header>
    </Headers>
  </Add>
  <Add>
    <Headers>
      <Header name="set-cookie">secondcookie=12345</Header>
    </Headers>
  </Add>
  <IgnoreUnresolvedVariables>true</IgnoreUnresolvedVariables>
  <AssignTo createNew="false" transport="http" type="request"/>
</AssignMessage>

 This is the debug output:

Apigee provides basic functionality to iterate these values (doc). As you can read, this is a Read-Only collection. You can use request.header.header_name.values.count to have the collection length and request.header.header_name.N to access to the values.

This is a sample JavaScript script with which you can try out these features.

// This return collection (https://docs.oracle.com/javase/7/docs/api/java/util/Collection.html)
var set_cookie_collection = context.getVariable("response.header.set-cookie.values");

// Returns an array containing all of the elements in this collection.
var set_cookie_array = set_cookie_collection.toArray();

// All the values of a particular header in the request, in the form of a single string.
var set_cookie_string = context.getVariable("response.header.set-cookie.values.string");

// Returns the number of elements in this collection.
var set_cookie_length = context.getVariable("response.header.set-cookie.values.count");

print("set-cookie collection: " + set_cookie_collection);
print("set-cookie array: " + set_cookie_array);
print("set-cookie string: " + set_cookie_string);
print("number of set-cookie headers: " + set_cookie_length);

var cookie_to_find = "secondcookie";

// When you use request.header.header_name.N the index starts at 1
for(var i = 1; i <= set_cookie_length; i++) {
    
  // extract value using builtin apigee capabilities (best-practice)
  var header = context.getVariable("response.header.set-cookie." + i);
  print("[BUILTIN] set-cookie["+i+"]: " + header)

  if(header.indexOf(cookie_to_find) !== -1){
    var extracted_value = header.split("=")[1];
    print("Cookie found at [" + i + "] with value " + extracted_value);
  }
}

// When you use arrays the index starts at 0
for(var i = 0; i < set_cookie_length; i++) {
  // extract value using using array
  print("[ARRAY] set-cookie["+i+"]: " + set_cookie_array[i]);
}

context.setVariable("found-value", extracted_value);

This is the debug output:

This is the javascript stepExecution-stdout:

set-cookie collection: [firstcookie=ABCDE, secondcookie=12345] 
set-cookie array: [Ljava.lang.Object;@2d2884d4 
set-cookie string: firstcookie=ABCDE, secondcookie=12345 
number of set-cookie headers: 2 
[BUILTIN] set-cookie[1]: firstcookie=ABCDE 
[BUILTIN] set-cookie[2]: secondcookie=12345 
Cookie found at [2] with value 12345 
[ARRAY] set-cookie[0]: firstcookie=ABCDE 
[ARRAY] set-cookie[1]: secondcookie=12345

I hope I have been exhaustive and that this can help you.

[Giupo · Accepted solution]

Hello,
I have faced this problem for several days, I will try to provide you with as many details as possible so as to help other readers as well.

First of all, I would like to point out that by making a no-route example proxy and adding a policy that adds two "set-cookie" headers in request, you will be able to see in the debug that Apigee merges the two headers.

This is the policy:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<AssignMessage continueOnError="false" enabled="true" name="AM_set-cookie">
  <DisplayName>AM_set-cookie</DisplayName>
  <Properties/>
  <Add>
    <Headers>
      <Header name="set-cookie">firstcookie=ABCDE</Header>
    </Headers>
  </Add>
  <Add>
    <Headers>
      <Header name="set-cookie">secondcookie=12345</Header>
    </Headers>
  </Add>
  <IgnoreUnresolvedVariables>true</IgnoreUnresolvedVariables>
  <AssignTo createNew="false" transport="http" type="request"/>
</AssignMessage>

 This is the debug output:

Apigee provides basic functionality to iterate these values (doc). As you can read, this is a Read-Only collection. You can use request.header.header_name.values.count to have the collection length and request.header.header_name.N to access to the values.

This is a sample JavaScript script with which you can try out these features.

// This return collection (https://docs.oracle.com/javase/7/docs/api/java/util/Collection.html)
var set_cookie_collection = context.getVariable("response.header.set-cookie.values");

// Returns an array containing all of the elements in this collection.
var set_cookie_array = set_cookie_collection.toArray();

// All the values of a particular header in the request, in the form of a single string.
var set_cookie_string = context.getVariable("response.header.set-cookie.values.string");

// Returns the number of elements in this collection.
var set_cookie_length = context.getVariable("response.header.set-cookie.values.count");

print("set-cookie collection: " + set_cookie_collection);
print("set-cookie array: " + set_cookie_array);
print("set-cookie string: " + set_cookie_string);
print("number of set-cookie headers: " + set_cookie_length);

var cookie_to_find = "secondcookie";

// When you use request.header.header_name.N the index starts at 1
for(var i = 1; i <= set_cookie_length; i++) {
    
  // extract value using builtin apigee capabilities (best-practice)
  var header = context.getVariable("response.header.set-cookie." + i);
  print("[BUILTIN] set-cookie["+i+"]: " + header)

  if(header.indexOf(cookie_to_find) !== -1){
    var extracted_value = header.split("=")[1];
    print("Cookie found at [" + i + "] with value " + extracted_value);
  }
}

// When you use arrays the index starts at 0
for(var i = 0; i < set_cookie_length; i++) {
  // extract value using using array
  print("[ARRAY] set-cookie["+i+"]: " + set_cookie_array[i]);
}

context.setVariable("found-value", extracted_value);

This is the debug output:

This is the javascript stepExecution-stdout:

set-cookie collection: [firstcookie=ABCDE, secondcookie=12345] 
set-cookie array: [Ljava.lang.Object;@2d2884d4 
set-cookie string: firstcookie=ABCDE, secondcookie=12345 
number of set-cookie headers: 2 
[BUILTIN] set-cookie[1]: firstcookie=ABCDE 
[BUILTIN] set-cookie[2]: secondcookie=12345 
Cookie found at [2] with value 12345 
[ARRAY] set-cookie[0]: firstcookie=ABCDE 
[ARRAY] set-cookie[1]: secondcookie=12345

I hope I have been exhaustive and that this can help you.

[Aravind]

@Giupo Thank you so much for the solution,Wil try this and let you know.

[Aravind · Accepted solution]

Thanks @Giupo. It works for me