This document summarizes an upcoming tour by Kevin Schroeder of Zend Technologies to discuss various topics including: - An introduction to Kevin and what he does at Zend - An overview of Zend products like Zend Framework and Zend Server - A discussion of performance, scalability, and queuing in PHP applications - A demonstration of using the Zend Server job queue to asynchronously process tasks - Considerations for deploying PHP applications in different environments like development, testing, staging, and production

1. Northeast User Group Tour – April 2011 By Kevin Schroeder Technology Evangelist Zend Technologies

2. About Kevin Past: Programming/Sys Admin Current: Technology Evangelist/Author/Composer @kpschrade

3. What do we do?

5. Zend Framework Zend Server PHP Test Application Performance Reliability & Management Scale-Out Enterprise Enablement Acceleration Monitoring Clustering Hot Fixes Optimization Root-Cause Job Queue Support Profile Caching Downloads Java Bridge Configuration Zend Studio (Eclipse-based) Debug Collaborate Linux (rpm/web repositories) IBM i (PTF) Windows (MSI)

6. A quick word on something new…

8. Wanna try it? Go to http://prerelease.adobe.com/callout/?callid=6C1235C63BDC414896951DDCEC01D5E8 … or go to http://www.eschrade.com/fbphp:-) Email me at kevin@zend.com (this will help expedite your approval)

9. Things we’re giving away

10. 1 Zend Certification Test (you still have to pass it) 1 copy of Zend Studio ElePHPants Books Dart Boards Little Note Books (the paper kind)

11. Queuing

12. Could your PHP apps benefit from being able to process data or execute asynchronously? Twtpoll results

13. Performance Execute logic apart from the main request (asynchronicity) Scalability The ability to handle non-immediate logic as resources are available Why would you want to queue?

14. People often say that performance and scalability are separate things. This is inaccurate (consider Google) Performance is the speed by which a request is executed Scalability is the ability of that request to maintain its performance as load/infrastructure increases Performance & Scalability

15. DON’T!! You are not Facebook You probably won’t be Don’t overcomplicate your problems by trying to be So how do you scale to Facebook size?

16. Typical anatomy of a PHP Application Bad for scala-bility! Presentation Application Control Database Access Business Logic Presentation Application Control Business Logic Presentation | 16

17. Good for Scalability Presentation Something.phtml Something.phtml Something.phtml Something.phtml Something.phtml Something.phtml Something.phtml Something.phtml Application Control Something.php Something.php Something.php Something.php Something.php Something.php Something.php Something.php Business Logic Something.php Something.php Something.php Something.php Something.php Something.php Something.php Something.php Database Access Something.php Something.php Something.php Something.php Something.php Something.php Something.php Something.php | 17 | 14-Apr-11

18. Defined tasks Loose coupling Resource discovery What helps make software scalable?

19. The Golden Rule of Scalability “It can probably wait”

20. Pre-caching data Data analysis Pre-analysis (predicting where your users will go) Data processing Pre-calculating (preparing data for the next request) Data is “out of date” once it leaves the web server Immediacy is seldom necessary Asynchronous execution uses

21. A sledgehammer can hit a machine Scalability and High Availability are yin and yang A site that can’t keep running is not scalable A site that can’t scale will fail (if it gets really popular) Machines can be added and removed at will Not “cloudy” necessarily No single point of failure Data exists in at least two, preferably at least three, places Characteristics

22. Waste disk space Control usage (don’t let users do anything they want) Pre-calculate as much as possible Calculate and cache/store Don’t scan large amounts of data Keep data processing off the front end servers Don’t just cache Don’t let it substitute for thought Cache hit rates can be meaningless if you have hundreds of cache hits for a request Considerations

24. Make as much as possible configurable/discoverableDecouple/Partition Don’t tie everything (relationships and such) into the database Use queues/messaging Stomp interfaces are really good for PHP – Can also use Java Bridge Zend_Queue has several interfaces Try to use stateless interfaces pollingis more scalable than idle connections; introduces lag Considerations

25. Use Cron /w PHP CLI (probably shouldn’t do this) Use Gearman Use home-grown (don’t do this) Use pcntl_fork() (NEVER do this) Use Zend Server Job Queue Options

26. Your only real options Very cloud friendly * I am not an expert on Gearman. Corrections will be taken in the spirit that they are given. For obvious reasons, I will focus on Zend Server

27. Schedule jobs in the future Set recurring jobs Execute immediately, as resources are available (my fav) Utilize ZendJobQueue() Using the Zend Server Job Queue

28. Job Queue Architecture – Elastic Backend Web Server /w JQ Web Server Users! Web Server /w JQ Web Server Load Balancer Web Server /w JQ Web Server Pros Scale the backend as necessary Default (easy) mechanism Cons Getting the job status requires using a DB

29. Job Queue Architecture – Elastic Frontend Web Server Web Server /w JQ Users! Web Server Web Server /w JQ Load Balancer Web Server Web Server /w JQ Pros Easy to communicate with the Job Queue server handling the job Cons Requires you to build your own interface

30. Create a task-handling controller Create an abstract task class Understands the Job Queue Self contained If Elastic Backend: connects to localhost If Elastic Frontend: connects to load balancer (my preferred), load balanced JQ servers manage themselves Execute the task, have it serialize itself and send it to send to the task handler Kevin’s favorite way to implement it

31. comendobqueueanager Handles connecting to the queue and passing results back and forth comendobqueueobAbstract Abstract class that a job would be based off of comendobqueueesponse The response from the manager when a job is queued. Contains the server name and job number orgschradeobscandir The actual job that scans the directory orgschradeobscandirResult An object that represents the data found Classes involved in the demo

32. Create job and set data Execute job Job passes itself to the queue manager Manager serializes job Manager uses HTTP call through a load balancer to queue the job The queue on the other end returns the job id and server name Job ID and server name is passed to the client Client polls the manager to get a completed job When the job is returned pass the serialized version of the executed job Execution Flow

33. Let’s write some code (no I’m not copping out with slides. We’re all told to show our work in grade skool)

34. Deployment

35. Agenda What we will be talking about Development->Testing->Staging->Production Rsync/SVN/PEAR/yum mechanisms What we will not be talking about Build tools (Phing, Maven, etc.) Database versioning/deployment Continuous Integration MSI installs (Sorry MS folks, I really wanted to but, y’know, time) Test-Driven Development

36. Before we get started Who here is a developer? Who here is a system administrator? Who here has an existing deployment strategy? Who here has edited a file in production? Who here has wished they didn’t?

37. Application Stages | 36 Increasing Maturity of PHP Applications Development Testing/QA Staging Production

38. Maturity | 37 Increasing Maturity of PHP Applications Uptime!! Testing & Validating Environment Testing & Validating Application Distinct Dev Environments Benefit Where are you? Structure

39. Development Purpose To provide developers an environment to write their code Characteristics Should be similar to production, though it usually isn’t Often security is more open Usually local to the developer

40. Consider Virtualization

41. Testing Purpose To provide a non-programming environment to test functionality Characteristics Continuous Integration could be included Generally no development occurs, only testing Developers should not do the testing, if possible Restricted outbound networking Use Zend Server Monitoring and Code Tracing to help reproduce errors

42. Prepared for and handed off to System Administrators (the stuff we’re here to talk about)

43. Staging Purpose To test your deployment process/scripting (not your code) Characteristics Developers generally do not have access, unless they are also the sysadmin Very restricted outbound networking Mirrors production as best as possible

44. Change Control A formal process used to ensure that changes are introduced in a controlled and coordinated manner Protect against unnecessary changes introduced to a system without forethought Requires documenting the release process Software version number Plans for rollback (tested? y/n) Expected outage time Customer impact Done prior to doing anything in production

45. Pre-Production (Optional) Purpose Test the code in the production environment without impacting customers Characteristics Not likely to have use in the cloud or large scale deployments Deployed in production immediately prior to making it live Test the application with production settings without customer interaction

47. Do whatever it is that it’s supposed to be doing

48. Characteristics

50. Deployment Option 1 – rsync Benefits Easy Already installed on your system Drawbacks No deployment script can be run Not integrated with either PHP or the OS Rollbacks require rolling back the entire source server Does not understand versioning One option is to move the source tree prior to the rsync Uses xinetd

51. Deployment Option 2 – Source Control Benefits Easy You should already be using source control Has versioning Can have pre/post install scripts Easy to do automatic deployments Drawbacks Do you want to put details on how to access your source code on your production box? Requires that your source control is accessible from production Deny access to .svn directories

52. Deployment Option 3 – PEAR Benefits Designed for PHP Very scriptable Natural for doing things like clearing a cache Has a better understanding of PHP Cross platform compatible Drawbacks Requires admins to be familiar with PHP code Limited to PHP deployment Available tooling is restrictive/build your own package.xml Define standardized locations (www, library, etc.)

53. Deployment Option 3 – PEAR Creating your PEAR Channel pear channel-discover pear.pirum-project.org pear install pirum/Pirum-beta vi /var/www/pear/pirum.xml <server> <name>localhost/pear</name> <summary>OurOrg PEAR channel</summary> <alias>helloworld</alias> <url>http://localhost/pear/</url></server> php ./pirum build /var/www/pear/

54. Deployment Option 3 - PEAR Creating your PEAR package php ./build-pear.php pear package pirum add /var/www/pear/ HelloWorld-0.1.3.tgz

55. Deploying your app pear channel-discover localhost/pear pear config-set www_dir /var/www pear install helloworld/HelloWorld pear clear-cache pear upgrade helloworld/HelloWorld Roll Back pear uninstall helloworld/HelloWorld pear install helloworld/HelloWorld-0.1.3

56. Deployment Option 4 - OS-based Benefits Easily added as part of your server deployment Very cloud friendly Admins already know how to use it Can describe OS-requirements/dependencies Downtime limited to actual install, not network transfer time Drawbacks Depends on environment Any PHP deployment scripting needs to be deployed with the application and executed in %post hook

57. Which should you use? Need something simple? rsync Need to deploy to multiple disparate platforms? PEAR Need to deploy internally/with minimal developer input?OS (yum/apt) If using the OS consider maintaining an internal “blessed” repository instead of depending on the distribution

58. Continuous Deployment Using automated deployment Very tight end-to-end integration Requires a lot of trust that the developers have a fully tested application w/ backend and frontend code Probably more work to manage if you can count the servers in your production environment with your fingers Could be beneficial but make sure you know what you’re doing You will need to have several testing experts

59. Takeaways No need for copy-and-paste deployment No need for (S)FTP (Kinda not good for deployment) Have an easy rollback mechanism Prepare for errors in deployment Try to minimize the amount of scripting needed for deployment Consider using VMs on anything important to keep downtime to zero bit.ly/phpDepAll

60. Follow us! Zend Technologies http://twitter.com/zend http://twitter.com/kpschrade (me!)

61. Get this information and all the examples at eschrade.com…