Google Cloud Functions - Sample Functions

Code samples to help you build your Google Cloud Function. The pieces of code show what a Google Cloud Function implementation looks like in different programming languages.

We have included two sample functions for you to use to accelerate your function development:

A sample function request and the generated response to help you understand Fivetran's request and response format and how to use the different nodes to write your cloud function.
A real-world sample function to retrieve data from the Transport API.

Sample function request

Node.js

/**
 * @param {!Object} req Cloud Function request context.
 * @param {!Object} res Cloud Function response context.
 */
exports.handler = (req, res) => {
    if (req.body.state === undefined) {
        res.status(400).send('No state is defined!');
    }
      
    if (req.body.secrets === undefined) {
        res.status(400).send('No secrets is defined!');
    }
        
    res.header("Content-Type", "application/json");
        		   
    res.status(200).send(update(req.body.state, req.body.secrets));
};

function update(state, secrets) {
    // Fetch records using api calls
    let [insertTransactions, deleteTransactions, newTransactionsCursor] = apiResponse(state, secrets);

    // Populate records and state
    return ({
        state: {
            transactionsCursor: newTransactionsCursor
        },
        insert: {
            transactions: insertTransactions
        },
        delete: {
            transactions: deleteTransactions
        },
        schema : {
            transactions : {
                primary_key : ['order_id', 'date']
            }
        },
        hasMore : false
    });
}

function apiResponse(state, secrets) {
    var insertTransactions = [
            {"date":'2017-12-31T05:12:05Z', "order_id":1001, "amount":'$1200', "discount":'$12'},
            {"date":'2017-12-31T06:12:04Z', "order_id":1001, "amount":'$1200', "discount":'$12'},
    ];

    var deleteTransactions = [
            {"date":'2017-12-31T05:12:05Z', "order_id":1000, "amount":'$1200', "discount":'$12'},
            {"date":'2017-12-31T06:12:04Z', "order_id":1000, "amount":'$1200', "discount":'$12'},
    ];

    return [insertTransactions, deleteTransactions, '2018-01-01T00:00:00Z'];
}

For more information about the fields in the request, see our request format documentation.

Generated response

The sample function request generates the following JSON response:

{
  "state": {
    "transactionsCursor": "2018-01-01T00:00:00Z"
  },
  "insert": {
    "transactions": [
      {
        "date": "2017-12-31T05:12:05Z",
        "order_id": 1001,
        "amount": "$1200",
        "discount": "$12"
      },
      {
        "date": "2017-12-31T06:12:04Z",
        "order_id": 1001,
        "amount": "$1200",
        "discount": "$12"
      }
    ]
  },
  "delete": {
    "transactions": [
      {
        "date": "2017-12-31T05:12:05Z",
        "order_id": 1000,
        "amount": "$1200",
        "discount": "$12"
      },
      {
        "date": "2017-12-31T06:12:04Z",
        "order_id": 1000,
        "amount": "$1200",
        "discount": "$12"
      }
    ]
  },
  "schema": {
    "transactions": {
      "primary_key": [
        "order_id",
        "date"
      ]
    }
  },
  "hasMore": "false"
}

For more information about the fields in the response, see our response format documentation.

Real-world sample function

Download our sample Transport - API (London Tube) function. Select your language to download the sample function (.zip file):

Create a function using the downloaded .zip file. For more information, see Deploying from Cloud Console.