Azure Function to Generate file from JSON contentByte - Microsoft Graph API Email generation

Frank
March 13, 2024
213 views
0 votes
2 Answers

Im having problem writting an azure function which takes blob input (JSON) and create a file using the contentbyte column from the JSON file.

JSON Template:

{
   "@odata.context":"https://graph.microsoft.com/v1.0/$metadata#users('XXX.com')/messages('AQMkADAA3D%3D')/attachments",
   "value":[
      {
         "@odata.type":"#microsoft.graph.fileAttachment",
         "@odata.mediaContentType":"application/pdf",
         "id":"AQMkADA0NjA5YT",
         "lastModifiedDateTime":"2023-06-29T14:40:33Z",
         "name":"MISC.pdf",
         "contentType":"application/pdf",
         "size":314000,
         "isInline":false,
         "contentId":"5E2D20ED5265174C8C9DC1AD59FFA4outlook.com",
         "contentLocation":null,
"contentBytes":"JVBERi0xLjYNCiWAgYKDDQoxIDAgb2JqDQo8PCAvQ3JlYXRvciA8Pg0KL0NyZWF0aW9uRGF0ZSA8NDQzYTM[enter image description here](https://i.stack.imgur.com/WQJSz.png)y"
      }
   ]
}

Azure Function:

enter image description here

Below is the azure function i wrote:

import json
import base64
from base64 import *
import logging
import azure.functions as func

def main(req: func.HttpRequest,inputBlob: func.InputStream, outputBlob: func.Out[bytes]) -> func.HttpResponse:
    logging.info('Python HTTP trigger function processed a request.')
    try:
 
        with open(inputBlob.read(),encoding='utf-8-sig') as user_file:
            file_contents = user_file.read()
            contents = json.loads(file_contents)
            
        for file_contents in enumerate(contents.get("value")):
            outputBlob.set(base64.b64decode(content.get("contentBytes")))
        
        output = {"run":"success"}
        return json.dumps(output)
     except Exception as ex:
        logging.exception(ex)
        output =  {"run":"failure"}   
        return json.dumps(output)

Below is the error msg"

[Error]   [Errno 36] File name too long: b'{rn   "@odata.context":"https://graph.microsoft.com/v1.0/$metadata#users('[email protected]')/messages('AQMkADA0NjA5YTMyLWU4MDctNDZkMi04

Answers

Chosen as BEST ANSWER
- Frank
- March 13, 2024 at 4:57 pm
- 0 votes
0
Thank you, Pavan. Your code helped me to identify the mistake i made. Below is the updated code I wrote which works great.
```
contents = json.loads(inputBlob.read()) 
for index,content in enumerate(contents.get("value")):
   fname = content.get("name")
   cbyte = content.get("contentBytes")
   conv_cbyte= base64.b64decode(cbyte)
   outputBlob1.set(conv_cbyte) 
       
```
Now, I'm using the for loop because we have multiple JSON content in the file. So we may have multiple files. In the above case, since the OUPUT Blob I specified the file name, it continue to overwrite the Test.PDF file again and again. Can you please advise how to save the file with the name from the json?

(Edit)

function which takes blob input (JSON) and create a file using the contentbyte column from the JSON file.

"File name too long," typically occurs when you attempt to create a file with a name that exceeds the maximum allowed length for file names, Ensure that the file name is not too long and does not contain any illegal characters.
I have created Http trigger function with runtime stack python. I am able to create a file of content byte and sent to storage container by using output binding like below:

function code:

import azure.functions as func
import logging
import base64

app = func.FunctionApp()

@app.route(route="http_trigger", methods=["POST"])
@app.blob_output(arg_name="output",
                path="pavan/pavan.pdf",
                connection="AzureWebJobsStorage")
def http_trigger(req: func.HttpRequest, output:func.Out[str]) -> func.HttpResponse:
    logging.info('Python HTTP trigger function processed a request.')

    try:
        req_body = req.get_json()
    except ValueError:
        return func.HttpResponse(
            "Invalid JSON input",
            status_code=400
        )

    if 'contentbyte' not in req_body:
        return func.HttpResponse(
            "Missing 'contentbyte' field in JSON",
            status_code=400
        )

    content_byte_base64 = req_body['contentbyte']

    # Decode base64 content byte
    try:
        content_bytes = base64.b64decode(content_byte_base64)
    except Exception as e:
        logging.error(f"Error decoding content byte: {str(e)}")
        return func.HttpResponse(
            "Error decoding content byte",
            status_code=500
        )

    # Decode content if it's encoded
    if 'encoding' in req_body and req_body['encoding'] == 'base64':
        try:
            content_bytes = base64.b64decode(content_bytes)
        except Exception as e:
            logging.error(f"Error decoding content: {str(e)}")
            return func.HttpResponse(
                "Error decoding content",
                status_code=500
            )

    # Write content to a file
    try:
        output.set(content_bytes)
    except Exception as e:
        logging.error(f"Error writing to file: {str(e)}")
        return func.HttpResponse(
            "Error writing to file",
            status_code=500
        )

    return func.HttpResponse(
        "File created successfully",
        status_code=200
    )