WE DID IT! DataStax Astra is GA

Yesterday we finally went full GA (General Availability) with DataStax Astra. For the quick TLDR think of it as Apache Cassandra that you can spin up as a service and use in about a minute. I, as I wrote about some months ago, joined the engineering team to help build out the system! I quickly got to reconnoitering the role and working toward build out of features, which now are available to you!

With Astra, if you’ve used Apache Cassandra or DataStax Enterprise you can use the same drivers or CQL you’re familiar with. But with Astra there are two additional capabilities we’ve just released to use in connecting to and working with your databases:

  • Astra REST API
  • Astra GraphQL API

With the REST API there are a number of capabilities to add a table, return a list of all the tables, return content of a table, and delete a table. In addition to tables, there is functionality to retrieve, retrieve all, add, update, and delete columns. All of the standard CRUD (Create, Read, Update, and Delete) commands can also be performed.

For the GraphQL API it gives you the ability to perform CRUD actions and query with filters using the GraphQL syntax.

Authorization Token

To use either of these services, the first thing you’ll need is to create one of Astra’s time based authorization tokens. These tokens work until 30 minutes after the last call made with the token. Once expired a new token must be created. To create a token an HTTP POST to the API can be made, passing several header values, and username and password in the body of a POST request.

For an example of retrieving an authorization token I’ve put together a cURL request below. To get the URL for your database navigate to the Astra dashboard, and on the summary screen of any database the API Access URL’s are listed.

curl --request POST \
  --url https://12c3bb24-e2df-4db3-b993-14707303e57c-us-east1.apps.astra.datastax.com/api/rest/v1/auth \
  --header 'accept: */*' \
  --header 'content-type: application/json' \
  --header 'x-cassandra-request-id: 24cc6f6f-c1d9-4d4e-a4d3-e34c7d8b148a' \
  --data '{"username":"betterbot","password":"betterbot"}'

A successful request will return a result with the auth token that looks like this.

{"authToken":"9a38437f-7e03-49a8-bc5d-b4e305d7c1e8"}

With that authorization token we can now call actions against the REST, or GraphQL APIs.

Creating a Table via the Astra REST API

To create a table, we need a few key elements: The table name, whether it should create if a table exists or not, and column definitions with at least one column as a primary key. This is done by using JSON to pass this schema to the REST API. Here’s an example of some JSON that can be used to create a table.

'{"name":"products","ifNotExists":true,"columnDefinitions":
  [ {"name":"id","typeDefinition":"uuid","static":false},
    {"name":"name","typeDefinition":"text","static":false},
    {"name":"description","typeDefinition":"text","static":false},
    {"name":"price","typeDefinition":"decimal","static":false},
    {"name":"created","typeDefinition":"timestamp","static":false}],"primaryKey":
    {"partitionKey":["id"]},"tableOptions":{"defaultTimeToLive":0}}'

To use this JSON to create a table, just add the pertinent headers, insert your keyspace into the URL, and the x-cassandra-token and POST this data to the REST API end point. A cURL request to create the table would look like this.

curl --request POST \
  --url https://12c3bb24-e2df-4db3-b993-14707303e57c-us-east1.apps.astra.datastax.com/api/rest/v1/keyspaces/betterbotz/tables \
  --header 'accept: */*' \
  --header 'content-type: application/json' \
  --header 'x-cassandra-request-id: 07e37064-b265-4618-94ce-1c4606f584f9' \
  --header 'x-cassandra-token: ' \
  --data '{"name":"products","ifNotExists":true,"columnDefinitions":
  [ {"name":"id","typeDefinition":"uuid","static":false},
    {"name":"name","typeDefinition":"text","static":false},
    {"name":"description","typeDefinition":"text","static":false},
    {"name":"price","typeDefinition":"decimal","static":false},
    {"name":"created","typeDefinition":"timestamp","static":false}],"primaryKey":
    {"partitionKey":["id"]},"tableOptions":{"defaultTimeToLive":0}}'

Adding data via a GraphQL Mutation

At this point, with a data created, we can add, update, or delete data. The sample curl statement I’ve put together here is a sample GraphQL mutation to add a record to the products table.

curl --request POST \
  --url https://ba965c97-86f1-4d38-8cne-58qa1d2209a1-us-east1.apps.astra.datastax.com/api/rest/v1/keyspaces/betterbotz/tables/orders/rows \
  --header 'accept: application/json' \
  --header 'content-type: application/json' \
  --header 'x-cassandra-request-id: xyzaa27b-de8e-4afc-8431-8f06a326047d' \
  --header 'x-cassandra-token: 3ad1ca6a-62pq-4e1b-b273-4c08ea334909' \
  --data-raw '{"query":"mutation {superarms: insertProducts(value:{id:\"65cad0df-4fc8-42df-90e5-4effcd221ef7\"\n name:\"Arm Spec A1\" description:\"Powerful Robot Arm Spec A.\"price: \"9999.99\" created: \"2012-04-23T18:25:43.511Z\"}){value {name description price created}}}","variables":{}}'

For some other examples issuing a GraphQL mutation to add a record, just for good measure.

Go

package main

import (
  "fmt"
  "strings"
  "net/http"
  "io/ioutil"
)

func main() {

  url := "https://32c3bb24-e2df-4db3-b993-14707303e57c-us-east1.apps.astra.datastax.com/api/graphql"
  method := "POST"

  payload := strings.NewReader("{\"query\":\"mutation {superarms: updateProducts(value: {id:\\\"65cad0df-4fc8-42df-90e5-4effcd221ef7\\\" name:\\\"Arm Spec A3 [Newly Updated]\\\" description:\\\"Powerful Robot Arm Spec A3.\\\" price: \\\"19999.99\\\" created: \\\"2012-04-23T18:25:43.511Z\\\" }){value {id name description price created}}}\",\"variables\":{}}")

  client := &http.Client {
  }
  req, err := http.NewRequest(method, url, payload)

  if err != nil {
    fmt.Println(err)
  }
  req.Header.Add("accept", "*/*")
  req.Header.Add("content-type", "application/json")
  req.Header.Add("X-Cassandra-Token", "e85b3021-fb89-4f43-9ba6-a64a49ba5f68")
  req.Header.Add("Content-Type", "application/json")

  res, err := client.Do(req)
  defer res.Body.Close()
  body, err := ioutil.ReadAll(res.Body)

  fmt.Println(string(body))
}

Python

import requests

url = "https://32c3bb24-e2df-4db3-b993-14707303e57c-us-east1.apps.astra.datastax.com/api/graphql"

payload = "{\"query\":\"mutation {superarms: updateProducts(value: {id:\\\"65cad0df-4fc8-42df-90e5-4effcd221ef7\\\" name:\\\"Arm Spec A3 [Newly Updated]\\\" description:\\\"Powerful Robot Arm Spec A3.\\\" price: \\\"19999.99\\\" created: \\\"2012-04-23T18:25:43.511Z\\\" }){value {id name description price created}}}\",\"variables\":{}}"
headers = {
  'accept': '*/*',
  'content-type': 'application/json',
  'X-Cassandra-Token': 'e85b3021-fb89-4f43-9ba6-a64a49ba5f68',
  'Content-Type': 'application/json'
}

response = requests.request("POST", url, headers=headers, data = payload)

print(response.text.encode('utf8'))

Java

OkHttpClient client = new OkHttpClient().newBuilder()
  .build();
MediaType mediaType = MediaType.parse("application/json");
RequestBody body = RequestBody.create(mediaType, "{\"query\":\"mutation {superarms: updateProducts(value: {id:\\\"65cad0df-4fc8-42df-90e5-4effcd221ef7\\\" name:\\\"Arm Spec A3 [Newly Updated]\\\" description:\\\"Powerful Robot Arm Spec A3.\\\" price: \\\"19999.99\\\" created: \\\"2012-04-23T18:25:43.511Z\\\" }){value {id name description price created}}}\",\"variables\":{}}");
Request request = new Request.Builder()
  .url("https://32c3bb24-e2df-4db3-b993-14707303e57c-us-east1.apps.astra.datastax.com/api/graphql")
  .method("POST", body)
  .addHeader("accept", "*/*")
  .addHeader("content-type", "application/json")
  .addHeader("X-Cassandra-Token", "e85b3021-fb89-4f43-9ba6-a64a49ba5f68")
  .addHeader("Content-Type", "application/json")
  .build();
Response response = client.newCall(request).execute();

and C#!

var client = new RestClient("https://32c3bb24-e2df-4db3-b993-14707303e57c-us-east1.apps.astra.datastax.com/api/graphql");
client.Timeout = -1;
var request = new RestRequest(Method.POST);
request.AddHeader("accept", "*/*");
request.AddHeader("content-type", "application/json");
request.AddHeader("X-Cassandra-Token", "e85b3021-fb89-4f43-9ba6-a64a49ba5f68");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\"query\":\"mutation {superarms: updateProducts(value: {id:\\\"65cad0df-4fc8-42df-90e5-4effcd221ef7\\\" name:\\\"Arm Spec A3 [Newly Updated]\\\" description:\\\"Powerful Robot Arm Spec A3.\\\" price: \\\"19999.99\\\" created: \\\"2012-04-23T18:25:43.511Z\\\" }){value {id name description price created}}}\",\"variables\":{}}",
           ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
Console.WriteLine(response.Content);

With that short tour, check out your free database today @ https://astra.datastax.com/register! Feel free to ping me on Twitter @Adron or here in comments, I’m open to and would love to discuss your experience!

Using Python’s Flask to Build a Basic API, Creating the didactic-engine-flask

I’ve worked with Python almost entirely from the maintenance programmer perspective. That is, I take other code written already, make edits, add features, and then redeploy it. I’ve created exactly zero greenfield applications in Python. That changes today however, with the creation of the didactic-engine-flask app!

Prerequisites

The only prereq to understanding this article is knowing git if you want to get the code, but it isn’t necessary. I’m starting this from ground zero. If you’re just getting started with Python, be sure to read “Getting Started With Python Right!” and “Unbreaking Python Through Virtual Environments” about setting up your environment. These two entries cover enough to ensure you won’t end up with broken, conflicted, and convoluted Python environments.

Mission: Build a Flask based API.

This post is about a singular thing, building an API with Flask. It won’t be about data modeling, databases, or wrapping middleware into the mix. It’s pure and simple Flask, with just the bare necessities needed to get an API working and responding appropriately requests. Continue reading “Using Python’s Flask to Build a Basic API, Creating the didactic-engine-flask”

Cedrick Lunven on Creating an API for your database with Rest, GraphQL, gRPC

Here’s a talk Cedrick Lunven (who I have the fortune of working with!) about creating API’s for your database, your distributed database. He starts out with a few objectives for the talk:

  1. Provide you a working API implementing Rest, gRPC, and GraphQL.
  2. Give implementation details through Demo.
  3. Reveal hints to choose and WHY, (specifically to work with Databases)

Other topics include specific criteria around conceptual data models, shifting from relational to distributed columnar store, with differentiation between entities, relationships, queries, and their respective behaviors. All of this is pertinent to our Killrvideo reference application we have too.

Enjoy!

Framework: Strongloop’s Loopback

Recently I did a series for New Relic on three frameworks, both for APIs and web apps. I titled it “Evaluating Node.js Frameworks: hapi.js, Restify, and Geddy” and it is available via the New Relic Blog. To check out those frameworks give that blog entry a read, then below I’ve added one more framework to the list, Strongloop’s Loopback.

Strength: Very feature-rich generation of models, data structures and related enterprise-type needs. Solid enterprise-style API framework library.
Weakness: Complexity could be cumbersome unless it is needed. Not an immediate first choice for a startup going after lean and clean.
Great for: Enterprise API Services.

When I dove into StrongLoop, I immediately got the feel that I was using a fairly polished package of software. When installing with ‘sudo npm install -g strongloop’ I could easily see the other packages that are installed. But instead of the normal Node.js display of additional dependencies that are installed, the StrongLoop install displayed a number of additional options with a shiny ASCII logo.
Continue reading “Framework: Strongloop’s Loopback”

Some JavaScript API Coding With Restify & Express & Hacking it With cURL …Segment #2

Ah, part 2! If you’re looking for part 1, click this link.

Review: In the last blog entry I went through more than a few examples of using cURL to issue GET requests against various end points using Node.js & Restify. I also covered the basics on where to go to find cURL in case it isn’t installed. The last part I covered was a little bit of WebStorm info to boot. In this part of the series I’m now going to dive into the HTTP verbs beyond GET.

POST

The practice around issuing a command via http verb to save data is via a post. When you issue a post via cURL use the -X followed by POST to designate a post verb, then -H to assign the content type parameter. In this particular example I’ve set it to application/json since my payload of data will be JSON format. Then add the final data with a -d option, followed by the actual data.

[sourcecode language=”bash”]curl -X POST -H "Content-Type: application/json" -d ‘{"uuid":"79E5591A-1E54-4562-A276-AFC266F54390","webid":"56E62C3A-D6BC-4F4F-B72A-E6CE081190B6"}’ http://localhost:3000/ident%5B/sourcecode%5D

Other data types can be sent, which the content type can be appropriately set for including; html, json, script, text or html. One example of this same command, issued with jQuery on the client side would actually look like this.

[sourcecode language=”javascript”]
var data = {"uuid":"79E5591A-1E54-4562-A276-AFC266F54390","webid":"56E62C3A-D6BC-4F4F-B72A-E6CE081190B6"};

$.post( "http://localhost:3000/ident", function( data ) {
$( ".result" ).html( data );
});
[/sourcecode]

When building post end points via express one of the things you may run into is the following message being displayed in the console.

[sourcecode language=”bash”]
/usr/local/bin/node app.js
connect.multipart() will be removed in connect 3.0
visit https://github.com/senchalabs/connect/wiki/Connect-3.0 for alternatives
connect.limit() will be removed in connect 3.0
[/sourcecode]

The immediate fix for this, until the changes are made (which may or may not mean to just alwasy  is to replace this line

[sourcecode language=”javascript”]
app.use(express.bodyParser());
[/sourcecode]

with these lines

[sourcecode language=”javascript”]
app.use(express.json());
app.use(express.urlencoded());
[/sourcecode]

So here’s some common examples for use from a great write up on writing basic RESTful APIs with Node.js and Express from the Modulus blog.

[sourcecode language=”javascript”]
var express = require(‘express’);
var app = express();

app.use(express.json());
app.use(express.urlencoded());

var quotes = [
{ author : ‘Audrey Hepburn’, text : "Nothing is impossible, the word itself says ‘I’m possible’!"},
{ author : ‘Walt Disney’, text : "You may not realize it when it happens, but a kick in the teeth may be the best thing in the world for you"},
{ author : ‘Unknown’, text : "Even the greatest was once a beginner. Don’t be afraid to take that first step."},
{ author : ‘Neale Donald Walsch’, text : "You are afraid to die, and you’re afraid to live. What a way to exist."}
];

app.get(‘/’, function(req, res) {
res.json(quotes);
});

app.get(‘/quote/random’, function(req, res) {
var id = Math.floor(Math.random() * quotes.length);
var q = quotes[id];
res.json(q);
});

app.get(‘/quote/:id’, function(req, res) {
if(quotes.length <= req.params.id || req.params.id < 0) {
res.statusCode = 404;
return res.send(‘Error 404: No quote found’);
}

var q = quotes[req.params.id];
res.json(q);
});

app.post(‘/quote’, function(req, res) {
if(!req.body.hasOwnProperty(‘author’) ||
!req.body.hasOwnProperty(‘text’)) {
res.statusCode = 400;
return res.send(‘Error 400: Post syntax incorrect.’);
}

var newQuote = {
author : req.body.author,
text : req.body.text
};

quotes.push(newQuote);
res.json(true);
});

app.listen(process.env.PORT || 3412);
[/sourcecode]

This is a great little snippet of code to use for testing your curling against just to check out.

References: