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Up to now, database is set and it’s main table ‘CallTable’ is populated through a c++ application, ‘SVRCapturer’, a VoIP call recorder. Now, let’s prepare a user interface to database content using a popular server side asynchronous utility nodejs, http://nodejs.org/

Start with getting node to a brand new vm. Nodejs can be obtained through backports repository for wheezy. However, here I will use curl option as given below,

database - installing nodejs

Connection to PostgreSQL database will be obtained using popular ‘pg’ module https://www.npmjs.com/package/pg. Let’s start with preparing ‘package.json’ to include this dependent module.

database - nodejs package json

Then running ‘npm install’ will get missing packages that are listed in ‘package.json’ and performs a local install.

database - using npm install

Make some use of ‘pg’ as follows. We will try to establish connection to PostgreSQL server and retrieve contents of ‘CallTable’ that has previously populated with c++ application. Give necessary privileges to user ‘svrserve’ by creting a role and modifying ‘/etc/postgresql/9.1/main/ph_hba.conf’ as demonstrated part I of this series.

database - initial svrserve to make database connection

If user ‘svrserve’ has been created successfully, the contents of ‘CallTable’ should be displayed properly,

database - initial result of svrserve to make database connection

Now display contents through web. But first we have to create certificates with openssl,

database - generating certificates through openssl

Then serving a web page is as easy as adding a few lines. This is where the elegance of nodejs comes. The following single page code is able to connect to a PostgreSQL server and display the contents of a table as web page. Of course there is pretty much space for hardening but what a fast prototyping!

database - svrserve as a prototype

Contents of ‘CallTable’ as a web page;

database - web display of svrserve as a prototype

Next step will be displaying content in a more elegant manner

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