POST request with wrk?

Question

I started to try wrk. It's very simple to use and very hard on the server, but I don't know how to perform other kind of request such as POST. In fact, I don't even know if this tool allows it. The documentation is very minimal.

Thanks

score 84 · Accepted Answer · edited Sep 01 '21 at 10:28

84

This is possible now. Here is an example https://github.com/wg/wrk/blob/master/scripts/post.lua.

wrk.method = "POST"
wrk.body   = "foo=bar&baz=quux"
wrk.headers["Content-Type"] = "application/x-www-form-urlencoded"

save this in a *.lua script and pass it into your command line test with the -s flag.

edited Sep 01 '21 at 10:28

Sergey Vyacheslavovich Brunov

17,291
7
48
81

answered Nov 12 '14 at 20:57

Steve

25,806
2
33
43

1

wow! Let me check that out. I'll switch the answer to your's if I can manage to make it work. Thanks for coming back to that post. – jackdbernier Nov 13 '14 at 06:09
1

You sir, are a life saver ! Just what I wanted. A simple and elegant way to test my post APIs. +1 – Saif Asif Jan 31 '16 at 06:16

score 36 · Answer 2 · edited Mar 18 '20 at 01:16

36

for those looking for a content-type "application/json" example:

wrk.method = "POST"
wrk.body = '{"firstKey": "somedata", "secondKey": "somedata"}'
wrk.headers["Content-Type"] = "application/json"

edited Mar 18 '20 at 01:16

Vlad Frolov

7,445
5
33
52

answered Jan 31 '19 at 09:36

Emmanuel N K

8,710
1
31
37

7

To post json data, this formatting actually works for me: `wrk.body = '{"firstKey": "somedata", "secondKey": "somedata"}'` – suvtfopw Jun 04 '19 at 10:37

score 13 · Answer 3 · answered Mar 30 '20 at 08:34

13

Here's an example lua script post_binary.lua for posting binary file: "Content-Type:application/octet-stream".

wrk.method = "POST"
wrk.headers["Content-Type"] = "application/octet-stream"

file = io.open("dog.jpg", "rb")
wrk.body = file:read("*a")

Then try: wrk "your_url" -s post_binary.lua --latency -t 1 -c 1 -d 30s -R 1

answered Mar 30 '20 at 08:34

hao

1,144
12
15

Just what I was looking for! – leonard Aug 20 '20 at 17:53

score 12 · Answer 4 · answered May 24 '19 at 20:06

I'll recommend using wrk2 instead of wrk since wrk2 provides better support for concurrent requests. When content-type header is application/json then please escape the special characters like \n with \\n and all other special characters present. Not doing this will send an invalid json to the upstream API, which will waste your time debugging.

Create a file with extension lua and paste the following in it. Save it and pass it along with -s flag to wrk2 command.

wrk.method = "POST"
wrk.body = "{\"firstKey\": 'somedata', \"secondKey\": 'somedata'}"
wrk.headers["Content-Type"] = "application/json"

Also you can add multiple header as

wrk.headers["Header1"] = "Header1_Val"
wrk.headers["Header2"] = "Header2_Val"
wrk.headers["Header3"] = "Header3_Val"
wrk.headers["Header4"] = "Header4_Val"

wrk2 -t500 -c1000 -d160s -R10000 -s ~/Documents/luaTestScript.lua http://localhost:8080/test_endpoint

POST request with wrk?

4 Answers4