No HTTP Trigger Found When Deploying FastAPI Azure Function (Python v2)

[yalcinsabancelebi]

Hello,

I’m using the Python v2 programming model in Azure Functions along with FastAPI. I’ve been successfully deploying my project until recently, when I began receiving this error during deployment:

No HTTP triggers found.

Here’s the full context:

---

I have not changed any of the following:

• host.json
• local.settings.json
• VS Code config files
• Azure Portal > Function App settings (Application Settings)

The only changes I've made are inside function_app.py and main.py (where FastAPI is used).

---

function_app.py

import azure.functions as func
from main import app as main

app = func.AsgiFunctionApp(app=main, http_auth_level=func.AuthLevel.ANONYMOUS)

@app.function_name(name="MatchTimerTriggerFunction")
@app.schedule(schedule="0 * * * * *", arg_name="myTimer", run_on_startup=False, use_monitor=True)
async def fifteen_timetrigger(myTimer: func.TimerRequest):
    if myTimer:
        print("Match Timer Trigger Function")

@app.function_name(name="CountdownTriggerFunction")
@app.schedule(schedule="0 * * * * *", arg_name="myTimer", run_on_startup=False, use_monitor=True)
async def countdown_timer(myTimer: func.TimerRequest):
    if myTimer:
        print("Countdown Timer Trigger Function")

@app.function_name(name="ExpiredMatchesTriggerFunction")
@app.schedule(schedule="0 * * * * *", arg_name="myTimer", run_on_startup=False, use_monitor=True)
async def countdown_timer(myTimer: func.TimerRequest):
    if myTimer:
        print("Expired Matches Trigger Function")

---

main.py (FastAPI Entry)

import fastapi
from fastapi.middleware.cors import CORSMiddleware

app = fastapi.FastAPI(...)

app.add_middleware(CORSMiddleware, ...)

from api.v1.homepage import router as homepage
app.include_router(homepage, prefix="/api/v1/homepage", tags=["Homepage"])

@app.get("/")
async def test():
    return {"message": "test"}

---

Project is modular. Example FastAPI route:

# api/v1/homepage/__init__.py
from fastapi import APIRouter, Depends, Query, Header
from fastapi.security import OAuth2PasswordBearer
from schemas.responses import StandardResponse

router = APIRouter()
oauth2_scheme = OAuth2PasswordBearer(tokenUrl="auth/login")

@router.get("", response_model=StandardResponse)
async def homepage(token: str = Depends(oauth2_scheme), timezone: str = Query(...), language: str = Header("en")):
    return StandardResponse(status="success", statusCode=200, data="homepage")

---

Everything works locally via func start.

---

Application Settings (Azure Portal) are verified:

• CosmosDB
• Blob Storage
• Application Insights
• AzureWebJobsStorage
• AzureWebJobsFeatureFlags = EnableWorkerIndexing

---

Dependencies (requirements.txt) are valid

• Fresh virtual environment installs correctly
• pip freeze matches expected output

---

Deployment Behavior

Sometimes deployment works and I see:

HTTP Trigger Urls:
  http_app_func: https://fifteen.azurewebsites.net//%7B*route%7D

But even with a minor change (like a print() statement), I get:

No HTTP triggers found.

---

Relevant Config Files

host.json

{
  "version": "2.0",
  "functionTimeout": "00:05:00",
  "extensions": {
    "http": {
      "routePrefix": ""
    }
  },
  "logging": {
    "applicationInsights": {
      "samplingSettings": {
        "isEnabled": true,
        "excludedTypes": "Request"
      }
    }
  },
  "extensionBundle": {
    "id": "Microsoft.Azure.Functions.ExtensionBundle",
    "version": "[4.*, 5.0.0)"
  }
}

local.settings.json

{
  "IsEncrypted": false,
  "Values": {
    "AzureWebJobsFeatureFlags": "EnableWorkerIndexing",
    "AzureWebJobsStorage": "<valid>",
    "FUNCTIONS_WORKER_RUNTIME": "python",
    "fifteen_DOCUMENTDB": "<valid>"
  },
  "ConnectionStrings": {}
}

function.json

{
  "scriptFile": "function_app.py",
  "bindings": [
    {
      "type": "httpTrigger",
      "direction": "in",
      "name": "req",
      "methods": ["get", "post", "delete", "options"],
      "authLevel": "anonymous"
    },
    {
      "type": "http",
      "direction": "out",
      "name": "$return"
    }
  ]
}

here is my file structure:

@eylulonar @frkinal

---

[nimbusnext-malhar]

I am seeing similar behavior, since last approx 10 days, see #2608

Some Old issues talk about startup problems, if module cryptography==44.0.0 is installed via requirements.txt I changed that in my deployment to cryptography==43.0.3. still some issues. so this is not it.

to compare notes, which plan your function is using?

[yalcinsabancelebi]

I am seeing similar behavior, since last approx 10 days, see #2608

Some Old issues talk about startup problems, if module cryptography==44.0.0 is installed via requirements.txt I changed that in my deployment to cryptography==43.0.3. still some issues. so this is not it.

to compare notes, which plan your function is using?

firstly thanks your attention. yes i have using but this lib but always used as cryptography==43.0.3 in my requirements file and have never changed it

[yalcinsabancelebi]

I am seeing similar behavior, since last approx 10 days, see #2608

Some Old issues talk about startup problems, if module cryptography==44.0.0 is installed via requirements.txt I changed that in my deployment to cryptography==43.0.3. still some issues. so this is not it.

to compare notes, which plan your function is using?

btw i'm using premium EP1 function app plan

[nimbusnext-malhar]

I see this behavior on Consumption Plan, as well as running on App service Plans

But the bare-code version which I test works on consumption plan

Where I have some dependencies, that version does not work anywhere but local. And I have neither time nor patience to maybe hunt one dependency via running different permutations of dependencies

I am seeing similar behavior, since last approx 10 days, see #2608 Some Old issues talk about startup problems, if module cryptography==44.0.0 is installed via requirements.txt I changed that in my deployment to cryptography==43.0.3. still some issues. so this is not it. to compare notes, which plan your function is using?

btw i'm using premium EP1 function app plan

[yalcinsabancelebi]

Maybe you can create a new venv file and new python environment good idea for your case as fresh start. Than use pip freeze and try deploy console command as func azure functionapp publish <your func app name>