FastAPI POST endpoint returning "Field required" when sending dictionary from Jython

Ignition
1

Hi everyone,

I'm trying to use a POST method:

h = {"accept": "application/json", "Content-Type": "application/json"}

client = system.net.httpClient()
response = client.post(url, data=data, headers=h)
response.json

data is a dictionary.

I get this error:

{'detail': [{'msg': 'Field required', 'loc': ['body'], 'type': 'missing', 'input': None}]}

For context, I’m using FastAPI for my API.

The endpoint is defined like this:

@app.post("/item")
def update_item(new_item: Item):
    ...

And the Item model looks like this:

class Item(BaseModel):
    t_stamp: str
    temp_1: float
    hum_1: float
    temp_2: float
    hum_2: float
    temp_3: float
    hum_3: float
    temp_4: float
    hum_4: float
    temp_5: float
    hum_5: float
    temp_6: float
    hum_6: float

The perplexing part is that if I use httpPost instead, it works fine:

import json

# Convert dictionary to JSON string
json_string = json.dumps(data)

# Use httpPost directly
response = system.net.httpPost(url, contentType="application/json", postData=json_string)

Thanks in advance for any help or advice

2

what happens if you try passing in json.dumps(data) to httpClient?

3

Can you share the actual dictionary you're sending?

What if you send your data to a testing tool like that echoes what you requested back to you?
I like http://httpbin.org/, though it appears to be down at the moment. It's self hostable via Docker: https://hub.docker.com/r/kennethreitz/httpbin/

4

Having same issue with put -

client = system.net.httpClient()
response = client.put(url, params = {'record_id':1} data={"ValueToUpdate":1.00}, headers=h)
response.json
5

Why would you expect PUT to have a response body at all?

1 Like
6

to see if the put was successful or was there any error.

1 Like
7

This code snippet doesn't have a comma between your two parameters.

8

yes,

here is my function :

def clientPut( path = '', id = None, payload = {}):
	if id is None:
		return
	headers = {
        "Content-Type": "application/json",
       "accept": "application/json"
        }
        
	client = system.net.httpClient()
	value =  client.put(path, params = {'record_id':id}, data = payload, headers=headers)
	print value.request.headers
	print value.json		
	return value.json

Here is the call:

clientPut(path = URL, id=411, payload = {"maximum":1.57})

this is what it prints when I use script console in designer:

{u'accept': [application/json], u'Content-Type': [application/json], u'User-Agent': [Ignition]}
{'detail': [{'msg': u'Field required', 'loc': [u'body'], 'type': u'missing', 'input': None}]}
{'detail': [{'msg': u'Field required', 'loc': [u'body'], 'type': u'missing', 'input': None}]}
9

Seems like a server problem to me; it works fine against an echo server:

from pprint import pprint

URL = "https://httpbingo.org/put"

def clientPut( path = '', id = None, payload = {}):
	if id is None:
		return
	headers = {
        "Content-Type": "application/json",
       "accept": "application/json"
        }
        
	client = system.net.httpClient()
	value =  client.put(URL, params = {'record_id':id}, data = payload, headers=headers)
	print value.request.headers
	return value.json
	
pprint(clientPut(path = URL, id=411, payload = {"maximum":1.57}))

>>>
{u'accept': [application/json], u'Content-Type': [application/json], u'User-Agent': [Ignition]}
{'args': {'record_id': [u'411']},
 'data': u'{"maximum":1.57}',
 'files': {},
 'form': {},
 'headers': {'Accept': [u'application/json'],
             'Content-Length': [u'16'],
             'Content-Type': [u'application/json'],
             'Host': [u'httpbingo.org'],
             'User-Agent': [u'Ignition'],
             'Via': [u'2 fly.io'],
             'X-Forwarded-For': [u'207.173.137.144, 66.241.125.232'],
             'X-Forwarded-Port': [u'443'],
             'X-Forwarded-Proto': [u'https'],
             'X-Forwarded-Ssl': [u'on'],
             'X-Request-Start': [u't=1763134710144631']},
 'json': {'maximum': 1.57},
 'method': u'PUT',
 'origin': u'207.173.137.144',
 'url': u'https://httpbingo.org/put?record_id=411'}
10

I messaged the full trace.

11

Try this, because some servers are bad at negotiating HTTP_2 downgrades.

Make this call:
client = system.net.httpClient()

Into:
client = system.net.httpClient(version="HTTP_1_1")

1 Like
Webhook Subscription
12

that did indeed work

1 Like