URL redirection in Tyk – Tyk

Redirecting APIs in Tyk is a common task that provides benefits like domain aliasing, keeping links alive, temporary responses to unsafe and long requests. These benefits greatly enhances the user experience by ensuring seamless navigation and efficient routing of requests. Whether you need to redirect traffic from an outdated endpoint to a new one or manage URL changes more effectively, Tyk provides the tools to accomplish this.

This guide will walk you through the steps to set up a redirect in Tyk, ensuring that your API traffic is efficiently managed and directed to the correct endpoints. We'll cover:

Different approaches to achieve redirects
Configuration examples with code snippets
Limitations and stop gaps

Straightforward redirection via inbuilt middleware

This approach leverages Tyk's built-in middleware functionality to return a redirection message/status code and the new location header pointing to the target URL. The combination of relative path matching, mock response middleware and a location header makes it possible to generate a simple redirect response. Here is a sample below

Mock response middleware via the endpoint designer in the dashboard

A request to this endpoint gets redirected to the Google search website via a browser. However, a 301 Moved Permanently response is generated via an API client such as curl.

Result of a curl request to the endpoint

curl -X GET -I http://localhost:8080/redirect-api/fulcrum/next
HTTP/1.1 301 Moved Permanently
Location: http://google.com
Date: Thu, 11 May 2023 13:05:43 GMT
Content-Length: 0

You can use the location option (-L ) within curl to follow through to the redirected URL.

curl -X GET -L http://localhost:8080/redirect-api/fulcrum/next

Lack of authentication, access control, logs and analytics record

Using mock middleware ignores authentication, access control, other Tyk middleware except version check and prevents the generation of gateway logs. Consequently, neither the gateway nor the pump will produce or purge any analytics record. We recommend using custom code for handling redirection if authentication, access control, inbuilt middleware, logging and/or analytics is crucial for your needs. This ensures that all relevant data is properly collected and available for analysis.

Enhanced redirection via custom code

This method offers more granular control over the redirect logic but requires developing custom code. The options here range from utilising virtual endpoint to any type of language supported by custom plugins. Your implementation may be as simple as inputting static values or dynamic as using parts of the URL path, query string or fragment component in the redirect location.

Simple virtual endpoint example

A snippet of a custom redirect virtual endpoint plugin

function simpleVirtualEndpointRedirect(request, session, config) { 
  log("Started: simpleVirtualEndpointRedirect")
  
  // Log request [object](https://tyk.io/docs/plugins/supported-languages/
javascript-middleware/middleware-scripting-guide/#the-request-object)
  log("Request: " + JSON.stringify(request)) 
  
  /* 
  * Copy and paste snippet logic below
  */
  
  var headers = { 
    "Content-Type" : "text/html",
    "Location": redirectURL
  };
  
  var responseObject = { 
    Code: 301, 
    Headers: headers
  }

  log("Finished: simpleVirtualEndpointRedirect")
  return TykJsResponse(responseObject, session.meta_data) 
}

URL path logic snippet

  // Log URL path
  log("URL Path: " + request.URL) 
  // Query params example
  redirectURL = "https://httpbin.org/anything/" + request.URL

Query param logic snippet

 // Log query param details.
 log("Query params: " + JSON.stringify(request.Params)) 
 // Query params example
 redirectURL = "https://google.com/search?q=" + request.Params["url"]

Headers logic snippet

  // Log header details.
  log("Query params: " + JSON.stringify(request.Headers)) 
  // Query params example
  redirectURL = "https://google.com/search?q=" + request.Headers["url"]

Key Session logic snippet

  // Log session [object](https://tyk.io/docs/plugins/supported-languages/javascript-middleware/middleware-scripting-guide/#the-session-object).
  log("Query params: " + JSON.stringify(session)) 
  // Key session example
  redirectURL = "https://google.com/search?q=" + session.url

Config data logic snippet

  // Log config [object](https://tyk.io/docs/plugins/supported-languages/javascript-middleware/middleware-scripting-guide/#the-config-object).
  log("Query params: " + JSON.stringify(config)) 
  // config data example
  redirectURL = "https://google.com/search?q=" + config.config_data.url

Advanced virtual endpoint example