cealloga

Ceallóga are simple ES6 arrow functions. Validate, test, and publish them as web service endpoints, and do it all via an easy-to-use rest API.

Requirements

• Node 6.11+
• MongoDB 3.4+

Install

npm install -g cealloga

Run

cealloga

Getting started

In this tutorial, we'll create a microservice that:

• takes information from a raw data source called colours
• sums the colours up and returns them as an object called chartData (something you might later consume in an UI component such as a bar chart, for example.)

Before we begin, let's dissect the uncompressed source code we want to host as a web service.

(ceallog) => {
    let colours = ceallog.vars.colours, // A list of colours, POSTed by the user in the request body.
        coloursMap = {}, // A map of colours, where key will be colour name ('yellow') and value a total (`2`).
        chartData = {labels: [], series: []} // Chart data to build from incoming colours
    
    if (colours) { // Sum the colours...
        colours.forEach(c => coloursMap[c.name] = coloursMap[c.name] + 1 || 1);
    }
    
    for (var name in coloursMap) { // Push the `name` into labels and `total` into series in the same order.
        let total = coloursMap[name];
        
        chartData.labels.push(name);
        chartData.series.push(total);
    }
    
    return chartData;
}

Validate

We create our code by first posting it to the /code/validate service. When we do this, the request is validated, the code is compiled, it's added to the database and cached on the server, and finally we receive a response with some information about it.

1. Save the following file as barchart.json.

{
   "name":"barchart",
   "label":"Colour Total Bar Chart",
   "body":"(ceallog)=>{let colours=ceallog.vars.colours,coloursMap={},chartData={labels:[],series:[]};if(colours){colours.forEach(c=>coloursMap[c.name]=coloursMap[c.name]+1||1)}for(var name in coloursMap){let total=coloursMap[name];chartData.labels.push(name);chartData.series.push(total)}return chartData;}"
}

2. In a terminal, run this curl command from the same directory as barchart.json:

curl -H "Content-Type: application/json" -X POST -d @barchart.json http://localhost:3000/code/validate

You should now have a response like the following. Copy the "service" value; you'll need it in the next example!

{
   "compiled":true,
   "id":"5a610660158ffae3135b7c7e",
   "created_date":"2018-01-18T20:41:04.849Z",
   "label":"Colour Total Bar Chart",
   "message":"Resource retrieved successfully.",
   "name":"barchart",
   "published":false,
   "service":"/cealloga/_test/5a610660158ffae3135b7c7e"
}

Test

Now that the code has been validated and created, let's send it some colour data and test the results.

1. Save the following file as colours.json.

{"colours": [{"name": "blue"}, {"name": "yellow"}, {"name": "red"}, {"name": "yellow"}]}

2. In a terminal, run this curl command from the same directory as colours.json:

curl -H "Content-Type: application/json" -X POST -d @colours.json http://localhost:3000/cealloga/_test/5a610660158ffae3135b7c7e # <- replace with your _test endpoint from the validate example

If you're seeing the following, it worked!

{
   "labels":[
      "blue",
      "yellow",
      "red"
   ],
   "series":[
      1,
      2,
      1
   ]
}

Publish

Once we're happy with the test results, we can publish the function by name as /cealloga/barchart.

Run the following curl command.

curl http://localhost:3000/code/publish/5a610660158ffae3135b7c7e # <- replace with the id from the validate example 

You should get a response like the following:

{
   "body":"(ceallog)=>{let colours=ceallog.vars.colours,coloursMap={},chartData={labels:[],series:[]};if(colours){colours.forEach(c=>coloursMap[c.name]=coloursMap[c.name]+1||1)}for(var name in coloursMap){let total=coloursMap[name];chartData.labels.push(name);chartData.series.push(total)}return chartData;}",
   "compiled":true,
   "created_date":"2018-01-18T20:41:04.849Z",
   "id":"5a610660158ffae3135b7c7e",
   "label":"Colour Total Bar Chart",
   "name":"barchart",
   "published":true,
   "service":"/cealloga/barchart"
}

Making a request to the published endpoint

The only thing left to day at this point is to check that /cealloga/barchart is up and running.

In a terminal, run this curl command from the same directory as colours.json:

curl -H "Content-Type: application/json" -X POST -d @colours.json http://localhost:3000/cealloga/barchart

As in the test example above, if you're seeing the following, it worked again!

{
   "labels":[
      "blue",
      "yellow",
      "red"
   ],
   "series":[
      1,
      2,
      1
   ]
}