Adding headers stored as a secret with the Request Transformer Advanced plugin

When testing the Kong Secrets Management with the Request Transformer Advanced plugin, you notice that the formatting is incorrect.

Example:

{
  "headers": {
    "%7B%22Name%22": "\"gruber\"}",
    "Accept": "*/*",
    "Host": "httpbin.org",
}

Failure to format this properly will result in extra characters being added to the header name, which in turn, get URL encoded as seen above.

To use a secret as a header, the correct format is to store the value as seen below.

headerName:headerValue

Examples:

Environment variable

For environment variables, including Docker and Kubernetes:

NEWHEADER="addMe:addValue"

Referenced as: config.add.header: {vault://env/newheader}

{
  "headers": {
    "Accept": "*/*",
    "Addme": "addValue",
    "Host": "httpbin.org",
}

AWS Secrets Manager

AWS Secrets Manager defaults to storing secrets as key/value pairs. To store headers in AWS Secrets Manager, there are a few options available.

Option 1:

Secret type: other type of secret

Key/value pairs: Choose plaintext, delete the default JSON formatting and replace it with the Header Name and Header Value separated by a colon.

Name: This can be whatever you like and will be used later when we reference the secret in the Request Transformer Plugin. For the example here I will name the secret header.

addMe:addValue

Referenced as: config.add.header: {vault://aws/secretname}

Option 2:

If the requirement is to store multiple Key/Value pairs inside one AWS Secret, then the Headers can be stored as a Key/Value pair inside the Secret Value. The Request Transformer Advanced plugin can then retrieve any specific Secret Value by referencing the Secret Key and add it as a header.

Referenced as: config.add.header: {vault://aws/secretname/header}