NERDZ-API - Back-end

In this folder you can find the NERDZ back-end implementation.

Back-end types architecture

In the implementation of the NERDZ's type hierarchy, a lot of data structure are generated in order to manipulate all the information that the social network manages. All the data structure are filled by a database ORM that is used to avoid to rely on the specific query dialect when creating each query. In order to work with it, a specific type has been defined in the file types.go which contains specific details that grant to the ORM to manage all the database's logic.

All the information it's not simply generated and consumed inside the system. In making available an API, we need to decouple all the internal data structure from the one that are returned to the user by the system. It's absolutely NOT correct to return all the data exactly has they are stored in the database. For this reason, according to the state-of-the-art pattern of the Transfer Object, we have defined a main structure and a specific transfer object type which can be generated from it.

In particular, each type defined in the file types.go implements a specific interface, called Transferable, which let to it to define how will be generated the companion transfer object type defined in the file api_types.go. Each transfer object type associated to the main struct, doesn't have all the ORM details and is completely seperated from the database's logic.

Working in this way, will be necessary, to get each transfer object specific type for a data structure, to work a little with type conversion and type switch. In a first moment this could be really tedious, but this approach has a lot of benefits that are appreciable only in the long-run.

Back-end tests

Tests are based on nerdz-test-db. If you want to run rests you must correctly setup this environment.

cd ~/nerdz_env/
git clone https://github.com/nerdzeu/nerdz-test-db.git

You don't need to do anything else in that folder.

Come back here and properly setup your JSON configuration file in order to use a new test-db.

Mine looks like:

{
    "DbUsername" : "test_db",
    "DbPassword" : "test_db",
    "DbName"     : "test_db",
    "DbHost"     : "127.0.0.1",
    "DbPort"     : 0,
    "DbSSLMode"    : "disable",
    "NERDZPath"  : "/home/paolo/nerdz_env/nerdz.eu/",
    "NERDZHost"  : "local.nerdz.eu",
    "EnableLog"  : true,
    "Port"       : 9090,
    "Scheme"     : "http",
    "Host"       : "local.api.nerdz.eu"
}

After that, configure the nvironment variables into test_all.sh.

Run the tests

To run all the test, you need a working database. If you wanto to automatically create a new database, use ./test_all.sh.

If your nerdz-test-db is just ready thus you don't need to create a new one, you can lunch tests in these two ways:

CONF_FILE="/path/to/conf_file/conf_file_name" go test

If you want to see which queries are executed run tests with EnableLog parameter set to true in the configuration file and using the verbose mode for the test tool:

CONF_FILE="/path/to/conf_file/conf_file_name" go test -v |less