Can't POST json data with curl in windows

Question

I have read several posts about this topic but i couldn't figure out how to send json data with curl POST on windows 10 (powershell).

I tried with \" or with """ nothing. json data:

{
    "frames": [
        {
            "text": "HOME2",
            "icon": "i294",
            "index": 0
        },
        {
            "text": "? 65",
            "icon": null,
            "index": 1
        }
    ]
}

Example of curl tries:

> curl -H "Accept: application/json" -H "X-Access-Token: xyz" -X POST "https://xyz" -d "{ """frames""": [{ """text""": """HOME2""", """icon""": """i294""", """index""": 0 }, { """text""": """? 65""", """icon""": null, """index""": 1 }]}"
{"error":{"code":null,"message":"Bad Request","trace":["request body must not be empty"]}}curl: (3) [globbing] bad range specification in column 2
curl: (6) Could not resolve host: text
curl: (6) Could not resolve host: HOME2,
curl: (6) Could not resolve host: icon
curl: (6) Could not resolve host: i294,
curl: (6) Could not resolve host: index
curl: (6) Could not resolve host: 0
curl: (3) [globbing] unmatched close brace/bracket in column 1
curl: (3) [globbing] unmatched brace in column 1
curl: (6) Could not resolve host: text
curl: (6) Could not resolve host: ? 65,
curl: (6) Could not resolve host: icon
curl: (6) Could not resolve host: null,
curl: (6) Could not resolve host: index
curl: (6) Could not resolve host: 1
curl: (3) [globbing] unmatched close brace/bracket in column 1

with \"

> curl -H "Accept: application/json" -H "X-Access-Token: xyz" -X POST "https://xyz" -d "{ \"frames\": [ { \"text\": \"HOME2\", \"icon\": \"i294\", \"index\": 0 }, { \"text\": \"? 65\", \"icon\": null, \"index\": 1 } ] }"
{"error":{"code":null,"message":"Bad Request","trace":["request body must not be empty"]}}curl: (3) [globbing] bad range specification in column 2
curl: (3) [globbing] unmatched brace in column 1
curl: (6) Could not resolve host: \text\
curl: (6) Could not resolve host: \HOME2\,
curl: (6) Could not resolve host: \icon\
curl: (6) Could not resolve host: \i294\,
curl: (6) Could not resolve host: \index\
curl: (6) Could not resolve host: 0
curl: (3) [globbing] unmatched close brace/bracket in column 1
curl: (3) [globbing] unmatched brace in column 1
curl: (6) Could not resolve host: \text\
curl: (6) Could not resolve host: \? 65\,
curl: (6) Could not resolve host: \icon\
curl: (6) Could not resolve host: null,
curl: (6) Could not resolve host: \index\
curl: (6) Could not resolve host: 1
curl: (3) [globbing] unmatched close brace/bracket in column 1
curl: (3) [globbing] unmatched close brace/bracket in column 1
curl: (3) [globbing] unmatched close brace/bracket in column 1

What am i doing wrong?

Answer 1

So, after further reading and from the answer from mohsen, I finalized my command line to:

curl -H "Accept: application/json" -H "X-Access-Token: xyz" -X POST "https://xyz" -d @exported.json

I added the json into a file called exported.json and now it is more compact and it still works.

The json data it self didn't need much more tweaking, see exported.json file:

{"frames":[{"text":"HOME2","icon":"i294","index":"0"},{"text":"? 65","icon":"null","index":"1"}]}

Answer 2

Looks like Windows command line and PowerShell messes with curl and JSON post data. Tried the following in CMD, PowerShell and WSL. WSL gives the result I expected, the other two fails. (originally tried to post data to Node-Red, and their official example failed, that was my WTF moment)

Try this (httpbin.org just echoes your data back this case):

curl -X POST -d '{"name":"Nick","a":32}' -H "Content-type:application/json" https://httpbin.org/anything

Response when called from WSL:

{
  "args": {},
  "data": "{\"name\":\"Nick\",\"a\":32}",
  "files": {},
  "form": {},
  "headers": {
    "Accept": "*/*",
    "Content-Length": "22",
    "Content-Type": "application/json",
    "Host": "httpbin.org",
    "User-Agent": "curl/7.71.1"
  },
  "json": {
    "a": 32,
    "name": "Nick"
  },
  "method": "POST",
  "origin": "*********",
  "url": "https://httpbin.org/anything"
}

Response when called from CMD / PS:

{
  "args": {},
  "data": "'{name:Nick,a:32}'",
  "files": {},
  "form": {},
  "headers": {
    "Accept": "*/*",
    "Content-Length": "18",
    "Content-Type": "application/json",
    "Host": "httpbin.org",
    "User-Agent": "curl/7.55.1"
  },
  "json": null,
  "method": "POST",
  "origin": "****",
  "url": "https://httpbin.org/anything"
}

Notice Content-Length is different and the json property in the response is null when called from cmd or ps.

But doing this does work from both WSL and cmd, but not from PowerShell: curl -d "{\"name\":\"Nick\",\"a\":32}" -H "Content-type:application/json" https://httpbin.org/anything

And this works in PowerShell but fails in the other two curl -d '{\"name\":\"Nick\",\"a\":32}' -H "Content-type:application/json" https://httpbin.org/anything

So yes, put your post data in a file. But of course, powershell has it's own rules, so in the others you can do -d @data.json, but in powershell you must fo -d `@data.json (backtick before the @ symbol)

Answer 3

first minify your json here, don't use pretty json.

try this:

curl -d 'curl -d '{"frames":[{"text":"HOME2","icon":"i294","index":0}, 
 {"text":"? 65","icon":null,"index":1}]}' -H 'Content-Type: application/json' 
 https://example.com/login

for more info check this site

Answer 4

I thought I would share my findings on this in case it helps others.

For me, to get this to work, I simply had to toggle the single and double quotes, ironically, making the JSON not correctly formatted:

DOES NOT WORK:

curl -X POST -H 'Content-type: application/json' -d '{"text":"Hello World"}' https://my-unique-slack-hooks-url-here.com

DOES WORK:

curl -X POST -H 'Content-type: application/json' -d "{'text':'Hello, World'}" https://my-unique-slack-hooks-url-here.com

Answer 5

For those who still encounter this kind of problem in Windows, use instead :

Invoke-RestMethod -Uri http://your-url:port/your-end-point -Method POST(or other) -ContentType "application/json" -InFile .\your-json-file

It worked for me