Merge pull request #219 from Lemoncode/feature/docker-compose-updates

Feature/docker compose updates

Author: JaimeSalas

01-contenedores/contenedores-v/01-load-balancer-host/load-balancer/Dockerfile

@@ -0,0 +1,3 @@
+FROM nginx
+
+ADD ./nginx.conf /etc/nginx/

01-contenedores/contenedores-v/01-load-balancer-host/load-balancer/nginx.conf

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+user root;
+error_log /var/log/nginx/error.log;
+pid /var/run/nginx.pid;
+events {
+    worker_connections 1024;
+    use epoll;
+}
+http {
+    upstream nodeapp {
+        server host.docker.internal:8081;
+        server host.docker.internal:8082;
+        server host.docker.internal:8088;
+    }
+    server {
+        server_name localhost;
+        listen 80;
+        error_log  /var/log/nginx/errorhttp.log;
+        access_log /var/log/nginx/accesshttp.log;
+        location / {
+            proxy_pass http://nodeapp;
+        }
+    }
+}

01-contenedores/contenedores-v/01-load-balancer-host/readme.md

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+## Load Balancer
+
+Contruimos nuestra aplicación:
+
+```bash
+cd server
+```
+
+```bash
+docker build -t myapp .
+```
+
+Ahora podemos ejecutar nuestra aplicación:
+
+```bash
+docker run -d --rm -p 8080:8080 --name myapp myapp
+```
+
+We can make a simple load testing by
+
+```bash
+ab -n 1000 -c 100 http://localhost:8080/
+```
+
+```bash
+Requests per second:    273.68 [#/sec] (mean)
+Time per request:       365.390 [ms] (mean)
+Time per request:       3.654 [ms] (mean, across all concurrent requests)
+Transfer rate:          56.39 [Kbytes/sec] received
+
+Connection Times (ms)
+              min  mean[+/-sd] median   max
+Connect:        0    1   1.5      0       7
+Processing:    55  354  67.9    339     492
+Waiting:       33  288  68.4    284     459
+Total:         55  354  67.6    339     492
+
+Percentage of the requests served within a certain time (ms)
+  50%    339
+  66%    385
+  75%    407
+  80%    425
+  90%    448
+  95%    464
+  98%    472
+  99%    480
+ 100%    492 (longest request)
+```
+
+Para escalar el número de peticiones vamos a utilizar un balanceador de carga.
+
+Create __load-balancer/nginx.conf__
+
+```
+user root;
+error_log /var/log/nginx/error.log;
+pid /var/run/nginx.pid;
+events {
+    worker_connections 1024;
+    use epoll;
+}
+http {
+    upstream nodeapp {
+        server localhost:8081;
+        server localhost:8082;
+        server localhost:8088;
+    }
+    server {
+        server_name localhost;
+        listen 80;
+        error_log  /var/log/nginx/errorhttp.log;
+        access_log /var/log/nginx/accesshttp.log;
+        location / {
+            proxy_pass http://nodeapp;
+        }
+    }
+}
+```
+
+Create __load-balancer/Dockerfile__
+
+```Dockerfile
+FROM nginx
+
+ADD ./nginx.conf /etc/nginx/
+```
+
+Create multiple instances
+
+```bash
+docker build -t myapp .
+docker run -d --rm -p 8081:8080 myapp
+docker run -d --rm -p 8082:8080 myapp
+docker run -d --rm -p 8083:8080 myapp
+```
+
+We can check that the apps are up and running
+
+```
+curl http://localhost:8081
+curl http://localhost:8082
+curl http: //localhost:8083
+```
+
+Now we can build our load balancer
+
+```bash
+cd load-balancer
+
+docker build -t myloadbalancer .
+```
+
+And run the balancer as follows
+
+```bash
+docker run -d --net=host --name mylb myloadbalancer
+```
+
+Check the load balancer
+
+```bash
+curl http://localhost/
+```
+
+Let's do another load test
+
+```bash
+ab -n 1000 -c 100 http://localhost/
+```
+
+```bash
+Requests per second:    2405.65 [#/sec] (mean)
+Time per request:       41.569 [ms] (mean)
+Time per request:       0.416 [ms] (mean*)
+
+              min  mean[+/-sd] median   max
+Connect:        0    0   0.4      0       2
+Processing:     6   39  11.2     38      88
+Waiting:        6   39  11.2     38      88
+Total:          8   40  11.2     38      89
+
+Percentage of the requests served within a certain time (ms)
+  50%     38
+  66%     43
+  75%     45
+  80%     46
+  90%     53
+  95%     65
+  98%     70
+  99%     75
+ 100%     89 (longest request)
+```
+
+## macos
+
+- https://docs.docker.com/desktop/networking/#i-want-to-connect-from-a-container-to-a-service-on-the-host
+
+Refactorizamos `load-balancer/nginx.conf`
+
+```diff
+http {
+    upstream nodeapp {
+-       server localhost:8081;
+-       server localhost:8082;
+-       server localhost:8088;
++       server host.docker.internal:8081;
++       server host.docker.internal:8082;
++       server host.docker.internal:8088;
+    }
+    server {
+        server_name localhost;
+        listen 80;
+        error_log  /var/log/nginx/errorhttp.log;
+        access_log /var/log/nginx/accesshttp.log;
+        location / {
+            proxy_pass http://nodeapp;
+        }
+    }
+}
+```
+
+```bash
+docker kill mylb
+```
+
+```bash
+docker rm mylb
+```
+
+```bash
+cd load-balancer
+
+docker build -t myloadbalancer .
+```
+
+```bash
+docker run -d -p 80:80 --name mylb myloadbalancer
+```
+
+```bash
+ab -n 1000 -c 100 http://localhost/
+```

01-contenedores/contenedores-v/01-load-balancer-host/server/Dockerfile

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+FROM node:22-alpine
+
+WORKDIR /opt/app
+
+COPY index.js .
+COPY package.json .
+COPY package-lock.json .
+
+RUN npm install --only=production
+
+EXPOSE 8080
+
+CMD [ "npm", "start" ]

01-contenedores/contenedores-v/01-load-balancer-host/server/index.js

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+const express = require('express');
+
+const PORT = 8080;
+
+const app = express();
+
+app.get('/', (req, res) => {
+    console.log(req);
+    res.send('Hello world\n');
+});
+
+app.listen(PORT);
+
+console.log(`Running on port: ${PORT}`);
+