resource-manager/docs/index.md

---
title: Welcome to gCube Resource Manager Service documentation
---

Resource Manager Service is a RESTful application which exposes operations via REST-API.

See the available [REST-API docs](../api-docs/index.html).

Base URL
========

In the production environment, its current value is


Authorization
=============

D4Science adopts state-of-the-art industry standards for authentication
and authorization. Specifically, the implementation fully adopts [OIDC
(OpenID Connect)](https://openid.net/connect) for authentication and UMA
2 (User-Managed Authorization) for authorization flows. [JSON Web Token
(JWT) Access token](https://jwt.io/) are used for both authentication
and authorization.

Obtain your Bearer token here:
<https://dev.d4science.org/how-to-access-resources>

Service
=======

You can call the methods of the Web Service by writing your own REST
client application or using existing REST client plugins.

HTTP Statuses
-------------

Any successful operation returns *200 OK* HTTP status code. The create
operation returns *201 Created*. Any Background operation returns *202
Accepted*. Any operation which does not provide any content return *204
No Content*.

The most common error status a client can obtain are:

-   **400 Bad Request** used to indicate a clients error
    <https://tools.ietf.org/html/rfc7231#section-6.5.1>;
-   **401 Unauthorized** used to indicate that the client does not
    provide the authorization token in the HTTP Header or the client has
    not enough right to perform such request
    <https://tools.ietf.org/html/rfc7235#section-3.1>;
-   **404 Not Found** used to indicate that the requested instance does
    not exist <https://tools.ietf.org/html/rfc7231#section-6.5.4>;
-   **405 Method Not Allowed** the used HTTP method is not supported for
    the requested URL
    <https://tools.ietf.org/html/rfc7231#section-6.5.5>. The response
    contains the *Allow* HTTP Header indicating the supported HTTP
    method for such URL
    <https://tools.ietf.org/html/rfc7231#section-7.4.1>;
-   **409 Conflict** the request could not be completed due to a
    conflict with the current state of the target resource (e.g. the
    name of the resource already exists)
    <https://tools.ietf.org/html/rfc7231#section-6.5.8>;
-   **500 Internal Server Error** indicate a server failure
    <https://tools.ietf.org/html/rfc7231#section-6.6.1>.

You can find a complete list of HTTP Status at
<https://httpstatuses.com/>

If you get a *500 Internal Server Error*, please report it in the [gCube
ticketing system](https://support.d4science.org).

Please use this checklist before reporting an error:

-   Replicate the request;
-   The failure could be temporal due to network error, server issue and
    many other temporal issues. For this reason, please retry the
    request after a certain amount of time before reporting the issue;
-   indicate how to replicate the error;
-   indicate the time when the error occurred (this simplifies
    identifying the issue).

HTTP Methods
------------

Resource Manager is a pure RESTful service. It uses standard HTTP Methods to perform
listing of collections and CRUD (Create Read Update Delete) operations
on instances.

:::{table} Supported operations
:align: center
:widths: grid


| Operation | HTTP Method | URL | Success HTTP Status | Safe | Idempotent |
|-----------|-------------|-----|---------------------|------|------------|
| **Supported<br/>HTTP Methods** | OPTIONS | /{COLLECTION}               | 204 No Content | Y | Y |
| **List**                   | GET     | /{COLLECTION}               | 200 OK         | Y | Y |
| **Count**                  | GET     | /{COLLECTION}?count=true    | 200 OK         | Y | Y |
| **Exists**                 | HEAD    | /{COLLECTION}               | 204 No Content | Y | Y |
| **Create**                 | POST    | /{COLLECTION}               | 201 Created    | N | N |
| **Supported<br/>HTTP Methods** | OPTIONS | /{COLLECTION}/{INSTANCE_ID} | 204 No Content | Y | Y |
| **Exist**                  | HEAD    | /{COLLECTION}/{INSTANCE_ID} | 204 No Content | Y | Y |
| **Read**                   | GET     | /{COLLECTION}/{INSTANCE_ID} | 200 OK         | Y | Y |
| **Update**                 | PUT     | /{COLLECTION}/{INSTANCE_ID} | 200 OK         | N | Y |
| **Patch**                  | PATCH   | /{COLLECTION}/{INSTANCE_ID} | 200 OK         | N | Y |
| **Delete**                 | DELETE  | /{COLLECTION}/{INSTANCE_ID} | 204 No Content | N | N |
| **Purge**                  | PURGE   | /{COLLECTION}/{INSTANCE_ID} | 204 No Content | N | N |
| **Purge**                  | DELETE  | /{COLLECTION}/{INSTANCE_ID}?purge=true | 204 No Content | N | N |


### About URL

The presented URL uses the following convention:

-   **{COLLECTION}** is the plural name of the entity type;
-   **{INSTANCE\_ID}** is an identification that enables univocally
    identifying the instance in the collection.

### About Safety and Idempotency properties

-   A method is *Safe* if it does not produce any side effects. \"This
    does not prevent an implementation from including behaviour that is
    potentially harmful, that is not entirely read-only, or that causes
    side effects while invoking a safe method\"
    <https://tools.ietf.org/html/rfc7231#section-4.2.1>;
-   A method is *Idempotent* if the same operation repeated multiple
    times has the same side effect than using it one time. \"repeating
    the request will have the same intended effect, even if the original
    request succeeded, though the response might differ\"
    <https://tools.ietf.org/html/rfc7231#section-4.2.2>.

You can find more information about HTTP Methods at
<https://restfulapi.net/http-methods/>

### Uncommon HTTP Methods

-   PATCH method allows to perform a differential update (i.e. an update
    which provides only the differences and not the whole new
    representation);
-   PURGE method is not a standard but is widely used in service which
    requires this action (e.g.
    [Varnish](https://varnish-cache.org/docs/3.0/tutorial/purging.html),
    [Squid](https://wiki.squid-cache.org/SquidFaq/OperatingSquid#How_can_I_purge_an_object_from_my_cache.3F)).
    gCat provides support for this method, but to support a wider range
    of clients, it also provides the Purge action via *DELETE* with the
    additional get parameter `purge=true`.

Content-Type
------------

Any request must contain an indication of the interesting content type.

The client must specify the **Accept** HTTP Header for any operation
returning a result.

``` {.rest}
Accept: application/json
```

For any operation sending content to the service, it is necessary to
specify the **Content-Type** HTTP Header.

``` {.rest}
Content-Type: application/json
```

The service accepts and returns only JSON objects.


Collections
-----------

The following collections are available 

....

Roles
-----

Any user has one or more roles in the catalogue. Only the VRE Manager
can assign roles to VRE users.

The catalogue uses the following hierarchic roles:

**Manager**:

:   .......;





Java Client
===========

We provide the following Java Client out-of-the-box.

> ::: {.tip}
> ::: {.title}
> Tip
> :::
>
> If you\'re coding in Java, it is recommended that you use this Java
> Client.
> :::

**Maven Coordinates**

``` {.xml}
<groupId></groupId>
<artifactId></artifactId>
<version></version>
```

**Methods Result**

The service exposes [its methods](../api-docs/index.html) using a
standard naming approach. Moreover, they accept (in the case of HTTP
POST/PUT methods) JSON objects.

> ::: {.important}
> ::: {.title}
> Important
> :::
>
> The result of all methods is always a JSON object as per below:
> :::


*Inputs are automatically validated before the request is served.*

**Usage examples**


Service Discovery on IS
=======================

The service can be discovered in the Facet Based IS as EService with the
following json query:

``` {.json}
{
    "@class": "EService",
    "consistsOf": [
        {
            "@class": "IsIdentifiedBy",
            "target": {
                "@class": "SoftwareFacet",
                "group": "org.gcube.resource-management",
                "name": "resource-manager"
            }
        }
    ]
}
```

Service Maven Coordinates
=========================

The maven coordinates of gCat service are:

``` {.xml}
<groupId>org.gcube.resource-management</groupId>
<artifactId>resource-manager</artifactId>
```