Python DateTime Error For Blob Events In Event Grid Azure Function

Issue Description

The Azure Event Grid Trigger function in python throws an error on receiving a blob event. The error is related to DateTime format. The date returned by the blob event to the python function cannot be parsed by python as the millisecond value has seven digits. E.g. the date ‘2018-12-09T23:47:03.285137Z’ cannot be parsed by python as the millisecond value has seven digits which is not recognized in python.

Result: Failure
Exception: ValueError: time data '2018-12-12T03:16:34.2191989Z' does not match format '%Y-%m-%dT%H:%M:%S.%fZ'
Stack:   File "/home/site/wwwroot/.python_packages/lib/python3.6/site-packages/azure/functions_worker/dispatcher.py", line 250, in _handle__invocation_request
    pytype=pb_type_info.pytype)
  File "/home/site/wwwroot/.python_packages/lib/python3.6/site-packages/azure/functions_worker/bindings/meta.py", line 285, in from_incoming_proto
    trigger_metadata=trigger_metadata)
  File "/home/site/wwwroot/.python_packages/lib/python3.6/site-packages/azure/functions_worker/bindings/eventgrid.py", line 94, in from_proto
    event_time=cls._parse_datetime(body.get('eventTime')),
  File "/home/site/wwwroot/.python_packages/lib/python3.6/site-packages/azure/functions_worker/bindings/meta.py", line 181, in _parse_datetime
    raise last_error
  File "/home/site/wwwroot/.python_packages/lib/python3.6/site-packages/azure/functions_worker/bindings/meta.py", line 176, in _parse_datetime
    dt = datetime.datetime.strptime(datetime_str, fmt)
  File "/root/.pyenv/versions/3.6.6/lib/python3.6/_strptime.py", line 565, in _strptime_datetime
    tt, fraction = _strptime(data_string, format)
  File "/root/.pyenv/versions/3.6.6/lib/python3.6/_strptime.py", line 362, in _strptime
    (data_string, format))

Steps to reproduce issue

#### STEP 1: CREATE AZURE FUNCTION

groupName="<resource_group_name>"
location="westeurope"
functionStorageName="<function_storage_account_name>"
appinsightsKey="<application_insights_instrumentation_key>"
appName="<function_app_name>"

#### CREATE RESOURCE GROUP

az group create --name $groupName --location $location

#### REGISTER EVENT GRID PROVIDER NAMESPACE

az provider register --namespace Microsoft.EventGrid

#### CREATE STORAGE ACCOUNT FOR FUNCTION APP
az storage account create --name $functionStorageName --location $location --resource-group $groupName --sku Standard_LRS --kind StorageV2

#### CREATE FUNCTION APP
az functionapp create --resource-group $groupName --os-type Linux --consumption-plan-location $location --runtime python --name $appName --storage-account $functionStorageName

#### CONFIGURE APP INSIGHTS FOR FUNCTION
az functionapp config appsettings set --name $appName --resource-group $groupName --settings "APPINSIGHTS_INSTRUMENTATIONKEY=$appinsightsKey"

#### STEP 2: WRITE FUNCTION CODE AND PUBLISH
func init testfunction --worker-runtime python
cd testfunction
func new --language python --template "Azure Event Grid trigger" --name EventGridTrigger
func azure functionapp publish $appName

#### STEP 3: CREATE A STORAGE ACCOUNT WHOSE EVENTS NEED TO BE RECORDED
generalStorageName="<storage_account_name>"
az storage account create --name $generalStorageName --location $location --resource-group $groupName --sku Standard_LRS --kind StorageV2
storageId=$(az storage account show --name $generalStorageName --resource-group $groupName --query id --output tsv)
accountKey=$(az storage account keys list --account-name $generalStorageName | grep "value" | awk -F ": " '{print $NF}' | sed 's/"//g' | head -1)

#### STEP 4: GET FUNCTION MASTER KEY FROM AZURE PORTAL (browse to 'Manage' section under the EventGridTrigger function)
functionMasterKey="<function_master_key>"
endpoint="https://$appName.azurewebsites.net/runtime/webhooks/eventgrid?functionName=EventGridTrigger&code=$functionMasterKey"

#### STEP 5: REGISTER EVENT GRID SUBSCRIPTION
az eventgrid event-subscription create --resource-id $storageId --name "myevtgridtrig" --endpoint $endpoint

#### STEP 6: UPLOAD A FILE TO STORAGE BLOB TO TEST EVENT
az storage container create --name test1 --account-name $generalStorageName --account-key $accountKey
echo "hello" > hello.txt
az storage blob upload --container-name test1 --account-name $generalStorageName --account-key $accountKey --file hello.txt --name "hello.txt"

STEP 7: REVIEW MONITOR OR APP INSIGHTS FOR LOGS/ERRORS

Resources

• https://docs.microsoft.com/en-us/azure/azure-functions/functions-bindings-event-grid#python-example
• https://docs.microsoft.com/en-us/azure/storage/blobs/storage-blob-event-quickstart?toc=%2Fazure%2Fevent-grid%2Ftoc.json

[elprans]

I’ll post a fix shortly

[kavithamadhavaraj]

@nicklooo Hi, my zip folder has /worker_venv/lib/python3.6/site-packages/azure/functions_worker/bindings/ this path only. I’m using --build-with-native-deps flag. This makes the folder structure to the above mentioned one. If not, I can see {zip folder}\.python_packages\lib\python3.6\site-packages\azure\functions_worker in my zip file. Nevertheless, when i made changes to the packages & my function app code, the new changes from the later was reflecting the portal but the fix in the package file didn’t work.