Creating a new resource

In this exercise we are going to use the REST interface in combination with the HTTP operations POST and PUT to create a resource on the server. In contrast to the previous module here we are going to use the command line tool cURL to access the catalog. cURL is a command line tool to transfer data from or to a server using one of the supported protocols (e.g. HTTP or FTP). For more about the tool have a look at here.

Creating a new workspace

In this module we are going to repeat the steps we have done in chapter Publishing a vector layer. But as we don't want to override our progress (or any individual changes) made to the workspace momo, we will create new workspace momo-rest for the ensuing exercises.

Open up the terminal (if not already openend) and type in the following command to create a new workspace named momo-rest:
```
  $ curl \
    -v \
    -u admin:momo-ws\
    -XPOST \
    -H "Content-type: text/xml" \
    -d "<workspace>
          <name>momo-rest</name>
        </workspace>" \
    http://localhost/geoserver/rest/workspaces
```
The call above differs in two essential points from the previous read operations: Unlike the HTTP operation GET we use the operation POST and in addition we transfer a XML content containing a simple workspace definition to the unique endpoint workspaces.

Hit Enter to execute the above command and you will see an output like this:

  * Hostname was NOT found in DNS cache
  *   Trying 127.0.0.1...
  * Connected to localhost (127.0.0.1) port 80 (#0)
  * Server auth using Basic with user 'admin'
  > POST /geoserver/rest/workspaces HTTP/1.1
  > Authorization: Basic YWRtaW46Z2Vvc2VydmVy
  > User-Agent: curl/7.35.0
  > Host: localhost:80
  > Accept: */*
  > Content-type: text/xml
  > Content-Length: 57
  >
  * upload completely sent off: 57 out of 57 bytes
  < HTTP/1.1 201 Created
  < Date: Wed, 03 Feb 2016 10:30:39 GMT
  < Location: http://localhost:80/geoserver/rest/workspaces/momo-rest
  * Server Noelios-Restlet-Engine/1.0..8 is not blacklisted
  < Server: Noelios-Restlet-Engine/1.0..8
  < Transfer-Encoding: chunked
  <
  * Connection #0 to host localhost left intact

Here, two informations are crucial to us:

HTTP/1.1 201 Created: The request has been successfully processed and the resource has been created.
http://localhost/geoserver/rest/workspaces/momo-rest: The REST endpoint URL of our new workspace.

We can verify that the workspace was actually created either by using the GeoServer UI or the REST interface:
- Open the GeoServer user interface, navigate to the page Data ❭ Workspaces and ensure a new workspace named momo-rest is available in the list.
- Open the terminal and run the following command to get a XML representation of all available workspaces:
```
  $ curl \
    -v \
    -u admin:momo-ws \
    -XGET \
    -H "Accept: text/xml" \
    http://localhost/geoserver/rest/workspaces
```

Creating a new store

Now that we have created a new workspace, we'll add a new data store to it. Here we are reusing the database we already created (and added to the geoserver).

Open the terminal and insert the following command to create a new PostGIS datastore named db_momo_ws_rest:

  $ curl \
    -v \
    -u admin:momo-ws \
    -XPOST \
    -H "Content-type: text/xml" \
    -d "<dataStore>
          <name>db_momo_ws_rest</name>
          <connectionParameters>
            <host>localhost</host>
            <port>5432</port>
            <database>db_momo_ws</database>
            <schema>geodata</schema>
            <user>momo</user>
            <passwd>momo</passwd>
            <dbtype>postgis</dbtype>
          </connectionParameters>
        </dataStore>" \
    http://localhost/geoserver/rest/workspaces/momo-rest/datastores

Hit Enter to execute the command. This will result in the following output, assuring that the store was successfully created:

  * Hostname was NOT found in DNS cache
  *   Trying 127.0.0.1...
  * Connected to localhost (127.0.0.1) port 80 (#0)
  * Server auth using Basic with user 'admin'
  > POST /geoserver/rest/workspaces/momo-rest/datastores HTTP/1.1
  > Authorization: Basic YWRtaW46Z2Vvc2VydmVy
  > User-Agent: curl/7.35.0
  > Host: localhost:80
  > Accept: */*
  > Content-type: text/xml
  > Content-Length: 347
  >
  * upload completely sent off: 347 out of 347 bytes
  < HTTP/1.1 201 Created
  < Date: Wed, 03 Feb 2016 10:59:04 GMT
  < Location: http://localhost:80/geoserver/rest/workspaces/momo-rest/datastores/db_momo_ws_rest
  * Server Noelios-Restlet-Engine/1.0..8 is not blacklisted
  < Server: Noelios-Restlet-Engine/1.0..8
  < Transfer-Encoding: chunked
  <
  * Connection #0 to host localhost left intact

Once again we can verify the successful creation in the GeoServer UI (Data ❭ Stores).

Publishing a layer

In the next step we're going to publish the table tbl_countries as a new layer.

Open the terminal and insert the following command to create a new feature type (and layer) named countries_rest:

  $ curl \
    -v \
    -u admin:momo-ws \
    -XPOST \
    -H "Content-type: text/xml" \
    -d "<featureType>
          <name>countries_rest</name>
          <nativeName>tbl_countries</nativeName>
          <title>Countries</title>
          <nativeCRS>EPSG:4326</nativeCRS>
          <enabled>true</enabled>
        </featureType>" \
  http://localhost/geoserver/rest/workspaces/momo-rest/datastores/db_momo_ws_rest/featuretypes

And again, verify that the response contains the lines

  HTTP/1.1 201 Created

and

  Location: http://localhost/geoserver/rest/workspaces/momo-rest/datastores/db_momo_ws_rest/featuretypes/countries_rest

Additionally we can also have a look at the preview page to ensure the layer is correctly published.

Create and upload style

We can use the REST API both to create a new style object in GeoServer and to insert an existing SLD-file into it. At first we need to create a new SLD file on our local machine we'll need in the next step. For this purpose we can use the style already used in the previous module.

Open the terminal and navigate to your home directory with:
```
  $ cd ~
```
Create and open a new SLD file countries-style.sld in this directory with:
```
  $ nano countries-style.sld
```
Copy the linked SLD content (see here) the newly created file and save it with Ctrl + O. You can now close the nano editor with Ctrl + X.

We will now create the style and upload the SLD file we just created.

Copy the following block into your terminal and execute it to create a new style object:

  $ curl \
    -v \
    -u admin:momo-ws \
    -XPOST \
    -H "Content-type: text/xml" \
    -d "<style>
          <name>countries_rest</name>
          <filename>countries-style.sld</filename>
        </style>" \
    http://localhost/geoserver/rest/workspaces/momo-rest/styles

And again, verify that the response contains the lines

  HTTP/1.1 201 Created

and

  Location: http://localhost:80/geoserver/rest/workspaces/momo-rest/styles/countries_rest

Afterwards we can upload the style created above with (Note: Ensure the path to file countries-style.sld is correct!):

  $ curl \
    -v \
    -u admin:momo-ws \
    -XPUT \
    -H "Content-type: application/vnd.ogc.sld+xml" \
    -d @countries-style.sld \
    http://localhost/geoserverrest/workspaces/momo-rest/styles/countries_rest

This command should complete with:
```
  HTTP/1.1 200 OK
```

Assign a layer style

After we have created the style, we can assign this style to the layer countries_rest.

Copy and execute the following command in the terminal window:

  $ curl \
    -v \
    -u admin:momo-ws \
    -XPUT \
    -H "Content-type: text/xml" \
    -d "<layer>
          <defaultStyle>
            <name>countries_rest</name>
            <workspace>momo-rest</workspace>
          </defaultStyle>
        </layer>" \
    http://localhost/geoserver/rest/layers/momo-rest:countries_rest

After finished with HTTP/1.1 200 OK we can open the preview page to review the changes made to the layer style.

Layer created and styled via the REST API.