Showcase geo tags for calls derived from x-forwarded-for header

web/Dockerfile

@@ -1,7 +1,16 @@
-FROM nginx:1.16
+FROM nginx:1.19
 
 EXPOSE 8080
 
+RUN echo "js_path /opt/nginx_js;" > /etc/nginx/conf.d/njs.conf
+RUN echo "\njs_import instana_random_geo.js;\n" >> /etc/nginx/conf.d/njs.conf
+RUN echo "\njs_set \$fake_ip instana_random_geo;\n" >> /etc/nginx/conf.d/njs.conf
+RUN sed -i '1i load_module \"modules/ngx_http_js_module.so\";' /etc/nginx/nginx.conf
+RUN sed -i '1i load_module \"modules/ngx_stream_js_module.so\";' /etc/nginx/nginx.conf
+RUN apt update -yqq && apt install nginx-module-njs -y
+RUN mkdir -p /opt/nginx_js
+COPY instana_random_geo.js /opt/nginx_js/instana_random_geo.js
+
 ENV CATALOGUE_HOST=catalogue \
     USER_HOST=user \
     CART_HOST=cart \
@@ -14,4 +23,3 @@ ENTRYPOINT ["/root/entrypoint.sh"]
 
 COPY default.conf.template /etc/nginx/conf.d/default.conf.template
 COPY static /usr/share/nginx/html
-

web/default.conf.template

@@ -54,26 +54,32 @@ server {
     #}
 
     location /api/catalogue/ {
+        proxy_set_header x-forwarded-for $fake_ip;
         proxy_pass http://${CATALOGUE_HOST}:8080/;
     }
 
     location /api/user/ {
+        proxy_set_header x-forwarded-for $fake_ip;
         proxy_pass http://${USER_HOST}:8080/;
     }
 
     location /api/cart/ {
+        proxy_set_header x-forwarded-for $fake_ip;
         proxy_pass http://${CART_HOST}:8080/;
     }
 
     location /api/shipping/ {
+        proxy_set_header X-Forwarded-For $fake_ip;
         proxy_pass http://${SHIPPING_HOST}:8080/;
     }
 
     location /api/payment/ {
+        proxy_set_header x-forwarded-for $fake_ip;
         proxy_pass http://${PAYMENT_HOST}:8080/;
     }
 
     location /api/ratings/ {
+        proxy_set_header x-forwarded-for $fake_ip;
         proxy_pass http://${RATINGS_HOST}:80/;
     }
 
@@ -82,4 +88,3 @@ server {
         access_log off;
     }
 }
-

web/instana_random_geo.js

@@ -0,0 +1,21 @@
+var items = [
+    // white house
+    "156.33.241.5",
+    // Hollywood
+    "34.196.93.245",
+    // Chicago
+    "98.142.103.241",
+    // Los Angeles
+    "192.241.230.151"
+];
+
+// we get a random ip address to simulate specific locations of the requester
+function get(r) {
+    if (process.env.NGINX_INJECT_FAKE_IP != '1') {
+        return false;
+    }
+
+    return items[Math.floor(Math.random() * items.length)];
+}
+
+export default get;