As the title said, I am now talking about how you can DPS with 1 single button on a raid boss like Patchwerk and such. Combined with a auto clicker it's like going AFK and have fun with dps!
Warlock Affliction talent tree and glyph spec
Talent Calculator - World of Warcraft
NOTE: Bane is a MUST talent for this spec. Haunt, Everlasting affliction, Amplify curse and Unstable Affliction too.
What kind of gear does the warlock need:
-Haste
-Hit
-Spirit
-Spell power
You need to have a minimum of 300 spell haste rating. And a minimum of 320-340 hit rating. On my own warlock I got 351 haste rating, with the grand spellstone that gives 60 haste rating.
The reason is because your shadow bolt needs to be a casting time of 2.3 seconds or less, and both haunt and unstable affliction needs to be 1.4 seconds or less.
With 351 haste rating, your casting time for those spells should be like this:
Shadow bolt - 2.26 seconds
Unstable affliction - 1.36 seconds
Haunt - 1.36 seconds
So 400 would be the ideal haste rating. But a minimum of 300 ensure you that your shadowbolt is at least 2.3 seconds, and haunt and unstable affliction 1.4 seconds.
About the hit rating, I have tested with my own Warlock and he got 312 hit rating, I am still doing fine DPS but sometimes a spell miss or get resisted, don't forget that dot ticks can also be resisted! So haste and hit are the stats you want to go for first. Imagine it like this:
You are casting a spell like Soulfire, 4 sec cast, but then the target resisted it, that means you wasted 4 seconds of time and lost 4 seconds of DPS, sure it's only 4 seconds, but what if other spells get resisted during overtime, that would lower your DPS.
Pet usage:
You can use all kind of pets except Voidwalker. I personally use my Felhunter on passive since it gives me extra spirit + int = more crit + more spell power.
Download link of the auto clicker:
Autoclicker.zip
Addon to bypass the text limit for macros:
Super Duper Macro : WoWInterface Downloads : Miscellaneous
Warlock affliction macro:
Code:
#showtooltip shadow bolt
/castsequence reset=target life tap, shadow bolt, haunt, corruption, unstable affliction, curse of agony, shadow bolt, shadow bolt, shadow bolt, haunt, shadow bolt, life tap, unstable affliction, shadow bolt, shadow bolt, shadow bolt, haunt, shadow bolt, curse of agony, unstable affliction, life tap, shadow bolt
How to set it up:
Okay first you need to download the auto clicker and the super duper macro addon.
Before you continue further, close your World of Warcraft client.
After you downloaded both of them, place the super duper macro addon in your addon map, extract it there and start WoW.
Enable "load out of date addons" if super duper macros addon isn't working for you.
From there, visit the trainer and take the spec and buy the glyphs I suggested.
After that, type /macro to open up your macro window. If done correctly, you see above a red window with yellow text: Super Duper Macro. Click on it.
From there, click on new > name your macro > press create > change name/icon > chose a icon > click on the most right black window where it says something like "type here your macro" > delete the text > copy + paste the macro I made
Then click save (it's right under) and drag your newly made macro to your action bar.
Now go near a heroic dummy training to test the macro.
Open up auto clicker and have your settings like this:

After that, target your target dummy and hover your mouse on the macro. Press F3 and see if your macros is working.
If all done correctly, your character will do the castsequence macro and DPSing while you can go AFK. Don't worry about DPS, I have tested it on my own and I have calculated and tested how you can get the most benefits for all spells. Here is a screenshot of the result I got:


As you can see on my screenshot I got average damage with only a auto clicker clicking on my macro.
Of course you can tweak the macro but then you need to calculate the timing, with the macro I used for myself my dots are getting 80 to 90% uptime, with unstable affliction being used earlier/later, same story with curse of agony, corruption on the other hand is getting a 100% uptime due it being refreshed by haunt.
I wouldn't advise depending on this macro during boss fights where you need to run but it's nice to use on a boss like Patchwerk since you just have to stand still and pressing buttons.
If there are any questions left or suggestions feel free to post here, I will answer as soon as possible.
for now, have fun with this and good luck 
EDIT 1:
According to aaró you can be banned by using a auto clicker. I myself haven't witnessed that yet but just a warning, else you will need some way to press the macro on a other way or just manual pressing is possible too.