Run Absolutely Everything* With uWSGI

A 2017 ConFoo presentation about uWSGI, the application server framework.

While its name may seem to imply that it's Python-only, uWSGI is a combination application server, proxy, process manager/monitor, async queue, cross-language RPC framework, and more.

We'll take a look at the broad features that make uWSGI an interesting option as an application server, and then show you how to concurrently serve Python, PHP, Ruby, Perl, Go, Lua, and Clojure applications, and use the built-in RPC, queue and in-memory cache.

Transcript

1. A Presentation RUN ABSOLUTELY EVERYTHING*WITH UWSGI CONFOO - MONTRÉAL 2017
2. OUTLINE 1. Hello 2. What is uWSGI? Why do we need it? 3. Structure/Organization 4. Languages 5. Configuration 6. Extra Extra
3. HELLO Joël Perras Web stuff @ Fictive Kin Distributed company, ~25 people, 9-ish timezones Primarily Python, but have Ruby/Erlang/PHP/JVM in production Client services & in-house application development
4. LOTS OF WORK WITH CLIENTS BIG AND SMALL
5. UWSGI? GESUNDHEIT!
6. PEP333 (2003) PEP3333 (2010) WSGI -> uWSGI Web Server Gateway Interface. Low level interface for mediating web servers (Apache/ nginx/etc.) and web applications. Originally Python-only. Extended to support much more.
7. HARD 1. TOOLS FOR BUILDING HOSTING SERVICES
8. uWSGI is more than an app server. “The uWSGI project has ISPs and PaaS (that is, the hosting market) as the main target.” Not your typical application server: - Proxy - Process manager - Load balancer - Router - Schedule/cron runner - Queue - Cache - RPC framework - Static file server
9. HARD 2. EXTENSIBLE & OPEN BY DEFAULT
10. uWSGI is more than an app server. - Binary protocol (uwsgi, lowercase!) - Extensible via request plugins to support multiple languages/ platforms, including Docker. - Emperor/vassal configuration for massive instance management/monitoring. - Open source, with commercial support.
11. STRUCTURE
12. uWSGI It’s possible to use uWSGI to fulfill the roles of nearly all the entities involved. However, a typical installation will have it act between the web server and the application callables. Flow — Basic web server uWSGI app instances static assets
13. uWSGI The core is composed of: - configuration - processes management - sockets creation - monitoring - logging - shared memory areas - IPC - cluster membership Flow — Basic core Lang 2 Lang 3 Lang 4 Lang 5 Gateways APP APP APP APP Loop Engines Vassals Lang 1
14. LANGUAGES AND PLATFORMS
15. HARD 1. SUPPORTED LANGUAGES
16. Languages - Python - Ruby - Lua - Perl - PHP - Go - Erlang - JVM - Mono ASP.NET - V8 (JavaScript)
17. HARD 2. PLATFORMS
18. Platforms - Linux 2.6/3.x - Free/Net/Open/DragonFly BSDs - Windows Cygwin - Mac OSX - OpenSolaris, Solaris >= 10 - NexentaOS - SmartOS - OpenIndiana - OmniOS - Debian/kFreeBSD - GNU/Hurd
19. HARD 3. BONUS
20. Bonus - Docker - Concurrently serve multiple versions of same language, e.g. Ruby 2.1.10 and 2.4.0 - Coroutines/fibres - External demonized (or not) services! - Memcached - Celery - PostgreSQL - etc.
21. CONFIGURATION
22. HARD 1. PYTHON
23. WSGI Python Application 1 [uwsgi] 2 http = :9090 3 wsgi-file = path/to/app.py 4 processes = 4 5 threads = 2 1 def application(env, start_response): 2 start_response('200 OK', [('Content-Type','text/html')]) 3 return [b"Hello World"] Config
24. Flask Python Application 1 [uwsgi] 2 socket = 127.0.0.1:3031 3 wsgi-file = app.py 4 callable = app 6 processes = 4 6 threads = 2 Config 1 from flask import Flask 2 3 app = Flask(__name__) 4 5 @app.route('/') 6 def index(): 7 return “Hello there"
25. Django Application 1 [uwsgi] 2 chdir=/path/to/your/project 3 module=mysite.wsgi:application 4 master=True 5 pidfile=/tmp/project-master.pid 6 vacuum=True 7 max-requests=5000 8 daemonize=/var/log/uwsgi/yourproject.log This assumes you have a top-level project package named mysite, and within it a module mysite/ wsgi.py that contains a WSGI application object.
26. Django Application 1 uwsgi --chdir=/path/to/your/project \ 2 --module=mysite.wsgi:application \ 3 --env DJANGO_SETTINGS_MODULE=mysite.settings \ 4 --master --pidfile=/tmp/project-master.pid \ 5 --socket=127.0.0.1:49152 \ # can also be a file 6 --processes=5 \ # number of worker processes 7 --uid=1000 --gid=2000 \ # if root, uwsgi can drop privileges 8 --harakiri=20 \ # respawn processes taking more than 20 seconds 9 --max-requests=5000 \ # respawn processes after serving 5000 requests 10 --vacuum \ # clear environment on exit 11 --home=/path/to/virtual/env \ # optional path to a virtualenv 12 --daemonize=/var/log/uwsgi/yourproject.log # background the process
27. HARD 2. RUBY
28. Ruby/Rack Application Need to build uWSGI with Ruby/Rack support, first. 1 make rack 2 UWSGI_PROFILE=rack make 3 make PROFILE=rack 4 python uwsgiconfig.py --build rack
29. Ruby/Rack Application Config 1 class App 2 3 def call(environ) 4 [200, {'Content-Type' => 'text/html'}, ['Hello']] 5 end 6 7 end 8 9 run App.new 1 [uwsgi] 2 socket = 127.0.0.1:3031 3 rack = app.ru 4 processes = 4 5 master = true
30. Sinatra Ruby Application Config 1 require 'sinatra' 2 3 get '/hi' do 4 "Hello World" 5 end 6 7 run Sinatra::Application 1 [uwsgi] 2 socket = 127.0.0.1:3031 3 rack = config.ru 4 master = true 5 processes = 4 6 lazy-apps = true
31. Bundler’ized Ruby Application 1 [uwsgi] 2 socket = 127.0.0.1:3031 3 rack = config.ru 4 master = true 5 processes = 4 6 lazy-apps = true 7 rbrequire = rubygems 8 rbrequire = bundler/setup 9 env = BUNDLE_GEMFILE=<path_to_your_Gemfile>
32. Bundler + RVM 1 [uwsgi] 2 socket = 127.0.0.1:3031 3 rack = config.ru 4 master = true 5 processes = 4 6 lazy-apps = true 7 rbrequire = rubygems 8 rbrequire = bundler/setup 9 env = BUNDLE_GEMFILE=<path_to_your_Gemfile> 10 gemset = ruby-2.0@foobar
33. HARD 3. JAVA
34. Java/JVM 1 public class Foobar { 2 static void main() { 3 4 // create an anonymous function 5 uwsgi.RpcFunction rpc_func = new uwsgi.RpcFunction() { 6 public String function(String... args) { 7 return "Hello World"; 8 } 9 }; 10 11 // register it in the uWSGI RPC subsystem 12 uwsgi.register_rpc("hello", rpc_func); 13 } 14 }
35. Java/JVM 1 import uwsgi 2 3 def application(environ, start_response): 4 start_response('200 OK', [('Content-Type','text/html')]) 5 yield "<h1>" 6 yield uwsgi.call('hello') 7 yield "</h1>" Necessary uWSGI bridge for RPC call. 1 [uwsgi] 2 plugins = python,jvm 3 http = :9090 4 wsgi-file = myapp.py 5 jvm-classpath = /opt/uwsgi/lib/uwsgi.jar 6 jvm-main-class = Foobar Config
36. HARD 4. GO
37. Go via GCCGO 1 package main 2 3 import "uwsgi" 4 import "net/http" 5 import "fmt" 6 7 8 9 func viewHandler(w http.ResponseWriter, r *http.Request) { 10 fmt.Fprintf(w, "<h1>Hello World</h1>") 11 } 12 13 func main() { 14 http.HandleFunc("/view/", viewHandler) 15 uwsgi.Run() 16 }
38. Go via GCCGO 1 gcc -fPIC -shared -o myapp.so myapp.go Build as shared library. 1 [uwsgi] 2 http-socket = :9090 3 http-socket-modifier1 = 11 4 go-load = ./myapp.so Config Goroutines work!
39. HARD 5. PHP
40. PHP (with nginx frontend) Config 1 [uwsgi] 2 plugins = php 3 socket = 127.0.0.1:3030 4 chown-socket = www-data:www-data 5 uid = phpapp 6 gid = phpapp 7 master = True 8 processes = 4 1 <?php echo "hello there"; ?> 1 location ~ \.php { 2 root /your_document_root; 3 include uwsgi_params; 4 uwsgi_modifier1 14; 5 uwsgi_pass 127.0.0.1:3030; 6 } Nginx
41. HARD 6. LUA
42. Lua Application, with coroutines! 1 function hello(wsapi_env) 2 local headers = { ["Content-type"] = "text/html" } 3 4 local function hello_text() 5 coroutine.yield("<html><body>") 6 coroutine.yield("<p>Hello Wsapi!</p>") 7 coroutine.yield("<p>PATH_INFO: " .. wsapi_env.PATH_INFO .. "</p>") 8 coroutine.yield("<p>SCRIPT_NAME: " .. wsapi_env.SCRIPT_NAME .. "</p>") 9 for i=0, 10000, 1 do 10 coroutine.yield(i .. "<br/>") 11 end 12 coroutine.yield("</body></html>") 13 end 14 15 return 200, headers, coroutine.wrap(hello_text) 16 end 17 18 return hello
43. Lua Application, with coroutines! 1 [uwsgi] 2 plugins = lua 3 socket = 127.0.0.1:3031 4 lua = hello.lua 5 async = 8 6 ; run the gc every 100 requests 7 lua-gc-freq = 100 Config
44. HARD BONUS CONFIGURATION FUN
45. Bonus Configuration Options - lazy-apps - `for…endfor` iteration - if-env - if-exists - harakiri - zerg - route-if-not - Emperor/Tyrant mode - subscribe-to - … hundreds more
46. Bonus Configuration Options Build your own uWSGI binary, with your application embedded. en build it with its own configuration file embedded within it as well. And then build it with your static assets, HTML, templates, etc.!
47. EXTRA EXTRA
48. HARD 1. QUEUE/SPOOLER
49. Config 1 [uwsgi] 2 ; a couple of placeholder 3 django_projects_dir = /var/www/apps 4 my_project = foobar 5 ; chdir to app project dir and set pythonpath 6 chdir = %(django_projects_dir)/%(my_project) 7 pythonpath = %(django_projects_dir) 8 ; load django 9 module = django.core.handlers:WSGIHandler() 10 env = DJANGO_SETTINGS_MODULE=%(my_project).settings 11 ; enable master 12 master = true 13 ; 4 processes should be enough 14 processes = 4 15 ; enable the spooler (the mytasks dir must exist!) 16 spooler = %(chdir)/mytasks 17 ; load the task.py module 18 import = task 19 ; bind on a tcp socket 20 socket = 127.0.0.1:3031
50. Python/Django 1 from uwsgidecorators import * 2 from django.contrib.sessions.models import Session 3 import os 4 5 @cron(40, 2, -1, -1, -1) 6 def clear_django_session(num): 7 print("it's 2:40 in the morning: clearing django sessions") 8 Session.objects.all().delete() 9 10 @spool 11 def encode_video(arguments): 12 os.system("ffmpeg -i \"%s\" image%%d.jpg" % arguments['filename'])
51. Python/Django 1 from task import encode_video 2 3 def index(request): 4 # launching video encoding 5 encode_video.spool(filename=request.POST['video_filename']) 6 return render_to_response('enqueued.html')
52. HARD 2. CACHE
53. django-uwsgi-cache 1 CACHES = { 2 'default': { 3 'BACKEND': 'uwsgicache.UWSGICache', 4 } 5 }
54. HARD 2. EXTERNAL DAEMONS
55. Memcached! 1 [uwsgi] 2 master = true 3 socket = :3031 4 smart-attach-daemon = /tmp/memcached.pid memcached -p 11311 -d -P /tmp/memcached.pid
56. Celery workers! 1 [uwsgi] 2 master = true 3 socket = :3031 4 smart-attach-daemon = /tmp/celery.pid celery -A tasks worker --pidfile=/tmp/celery.pid Celery beat! 1 [uwsgi] 2 master = true 3 socket = :3031 4 legion-mcast = mylegion 225.1.1.1:9191 90 bf-cbc:mysecret 5 legion-smart-attach-daemon = mylegion /tmp/celery- beat.pid celery beat --pidfile=/tmp/celery-beat.pid
57. HARD 4. STATIC FILE SERVER
58. Who needs nginx?! 1 [uwsgi] 1 offload-threads = 6 2 static-map = /static=/var/www/app/static 3 static-map = /media=/var/www/app/assets 4 static-expires = /var/www/app/static/* 3000000
59. HARD 4. SSL TERMINATION/REDIRECT
60. HTTP→HTTPS with Termination 1 https2 = addr=0.0.0.0:4443,cert=domain.crt,key=domain.key 2 http-to-https = 0.0.0.0:8000
63. FIN @JPERRAS NERDERATI.COM