SERA integration on Fastly¶

Kindly follow the below examples to setup the routing of bot traffic to SERA.

Change YOUR_TOKEN to the SERA token shared with you
Keep the relevant bot user-agent regex condition mentioned below - to control the traffic being sent to SERA

(1) Create a backend in the Fastly service¶

Clone the currently active version and create a backend for SERA.
You can use the following example code snippet for creating a SERA backend in your Fastly service.

backend o_s {
    .always_use_host_header = true;
    .between_bytes_timeout = 5s;
    .connect_timeout = 10s;
    .dynamic = true;
    .first_byte_timeout = 45s;
    .host = "sera.n7.io";
    .host_header = "sera.n7.io";
    .port = "443";
    .ssl = true;
    .ssl_check_cert = never;
    .ssl_sni_hostname = "sera.n7.io";
}

(2) Route Crawler requests to SERA¶

Use the same draft intercept and route the crawler requests to SERA.
Please refer to the following VCL snippet to intercept and route the required crawler requests to SERA in vcl_recv subroutine.
You need to add the following snippet in addition to your previous configuration(if any).
Note: Do not replace vcl_recv subroutine as it is if you have any existing configuration.

sub vcl_recv {
    # only send PAGE requests to SERA
    if (req.url !~ "(?i).*\.(jpg|jpeg|png|webp|avif|gif|bmp|ico|svg|js|css|woff|woff2|ttf|eot|otf|mp3|mp4|mov|ogg|webm|wav|exe|json|txt|xml|zip|csv|pdf|php|jsp|ashx|aspx|asmx)(\?.*)*$" 
        && !req.http.x-nv-app
        && !req.http.x-nv-sera-bypass) {
        # DURING POC PHASE - USE THIS if condition for bot User-Agent check :
        if (req.http.User-Agent ~ "(?i)(n7TestUserAgent|PTST|GTmetrix)") {
        # ON GOING LIVE ON SERA - USE THIS if condition for bot User-Agent check :
        if (req.http.User-Agent ~ "(?i)(googlebot|google\ page\ speed|chrome-lighthouse|google-inspectiontool|PTST|GTmetrix)") {
            set req.http.X-NV-Sera-Token = {YOUR_TOKEN};
            set req.backend = F_o_s;
            return(lookup);
        }
    }

    # existing configuration
}

You can test the Fastly configuration on Fiddle
Keep refining the logic by adjusting user-agent list, and SERA exclusion-patterns as needed.
Test thoroughly:
- WPT and GTMetrix will automatically receive the response from SERA due to the routing rule set above.
  - Steps to validate page using WPT
- To check the SERA rendered page on browser, you can use some browser extension (like Simple modify headers) to manipulate the browser user-agent.
  If in testing phase, use these user-agent values:
  For desktop:
```
n7TestUserAgent
```
  For mobile:
```
n7TestUserAgent; Android
```
  If SERA is live, you can use these actual bot user-agent values:
  For desktop:
```
Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Googlebot/2.1; +<http://www.google.com/bot.html)> Chrome/W.X.Y.Z Safari/537.36
```
  For mobile:
```
Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/W.X.Y.Z Mobile Safari/537.36 (compatible; Googlebot/2.1; +<http://www.google.com/bot.html)>
```
On go-live day, set the user-agent condition regex to actual bot user-agent values. Additionally, ensure that your condition is case-insensitive.

SERA integration on Fastly¶

(1) Create a backend in the Fastly service¶

(2) Route Crawler requests to SERA¶

Testing and Refinement¶