Create Google Cloud Function Using API In Python

I'm working on a project with Python(3.6) & Django(1.10) in which I need to create a function at Google cloud using API request. How can upload code in the form of a zip archiv

Solution 1:

In the request body you have a dictionary "CloudFunction" inside the request. The content of "CloudFunction" should be directly in request.

request_body = {
    "name": parent + '/functions/' + name,
    "entryPoint": entry_point,
    "sourceUploadUrl": upload_url,
    "httpsTrigger": {}
}

I recomend using "Try this API" to discover the structure of projects.locations.functions.create .

"sourceArchiveUrl" and "sourceUploadUrl" can't appear together. This is explained in Resorce Cloud Function:

// Union field source_code can be only one of the following:
"sourceArchiveUrl": string,
"sourceRepository": { object(SourceRepository) },
"sourceUploadUrl": string,
// End of list of possible types for union field source_code.

In the rest of the answer I assume that you want to use "sourceUploadUrl". It requires you to pass it a URL returned to you by .generateUploadUrl(...).execute(). See documentation:

sourceUploadUrl -> string

The Google Cloud Storage signed URL used for source uploading, generated by [google.cloud.functions.v1.GenerateUploadUrl][]

But before passing it you need to upload a zip file to this URL:

curl -X PUT "${URL}" -H 'content-type:application/zip' -H 'x-goog-content-length-range: 0,104857600'  -T test.zip

or in python:

    headers = {
        'content-type':'application/zip',
        'x-goog-content-length-range':'0,104857600'
    }
    print(requests.put(upload_url, headers=headers, data=data))

This is the trickiest part:

• the case matters and it should be lowercase. Because the signature is calculated from a hash (here)

• you need 'content-type':'application/zip'. I deduced this one logically, because documentation doesn't mention it. (here)

• x-goog-content-length-range: min,max is obligatory for all PUT requests for cloud storage and is assumed implicitly in this case. More on it here

• 104857600, the max in previous entry, is a magical number which I didn't found mentioned anywhere.

where data is a FileLikeObject.

I also assume that you want to use the httpsTrigger. For a cloud function you can only choose one trigger field. Here it's said that trigger is a Union field. For httpsTrigger however that you can just leave it to be an empty dictionary, as its content do not affect the outcome. As of now.

request_body = {
    "name": parent + '/functions/' + name,
    "entryPoint": entry_point,
    "sourceUploadUrl": upload_url,
    "httpsTrigger": {}
}

You can safely use 'v1' instead of 'v1beta2' for .create().

Here is a full working example. It would be to complicated if I presented it to you as part of your code, but you can easily integrate it.

import pprint
import zipfile
import requests
from tempfile import TemporaryFile
from googleapiclient import discovery

project_id = 'your_project_id'
region = 'us-central1'
parent = 'projects/{}/locations/{}'.format(project_id, region)
print(parent)
name = 'ExampleFunctionFibonacci'
entry_point = "fibonacci"

service = discovery.build('cloudfunctions', 'v1')
CloudFunctionsAPI = service.projects().locations().functions()
upload_url = CloudFunctionsAPI.generateUploadUrl(parent=parent, body={}).execute()['uploadUrl']
print(upload_url)


payload = """/**
 * Responds to any HTTP request that can provide a "message" field in the body.
 *
 * @param {Object} req Cloud Function request context.
 * @param {Object} res Cloud Function response context.
 */
exports.""" + entry_point + """= function """ + entry_point + """ (req, res) {
  if (req.body.message === undefined) {
    // This is an error case, as "message" is required
    res.status(400).send('No message defined!');
  } else {
    // Everything is ok
    console.log(req.body.message);
    res.status(200).end();
  }
};"""


with TemporaryFile() as data:
    with zipfile.ZipFile(data, 'w', zipfile.ZIP_DEFLATED) as archive:
        archive.writestr('function.js', payload)

    data.seek(0)
    headers = {
        'content-type':'application/zip',
        'x-goog-content-length-range':'0,104857600'
    }
    print(requests.put(upload_url, headers=headers, data=data))

# Prepare Request Body
# https://cloud.google.com/functions/docs/reference/rest/v1/projects.locations.functions#resource-cloudfunction

request_body = {
    "name": parent + '/functions/' + name,
    "entryPoint": entry_point,
    "sourceUploadUrl": upload_url,
    "httpsTrigger": {},
    "runtime": 'nodejs8'
}

print('https://{}-{}.cloudfunctions.net/{}'.format(region,project_id,name))
response = CloudFunctionsAPI.create(location=parent, body=request_body).execute()

pprint.pprint(response)

Open and upload a zip file like following:

file_name = os.path.join(IGui.settings.BASE_DIR, 'media/archives/', func_obj.sourceFile.name)
headers = {
    'content-type': 'application/zip',
    'x-goog-content-length-range': '0,104857600'
}

with open(file_name, 'rb') as data:
    print(requests.put(upload_url, headers=headers, data=data))