RESTCONF Server implements the RESTCONF protocol [RFC8040]. It communicates with a RESTCONF Client through a Web Server, an Apache HTTP Server.

In case HTTPS protocol is used the TLS channel is managed by the Web Server.  Refer to the installation manual for more details on how to configure TLS.


RESTCONF Client is implemented as a feature of yangcli-pro client. Existing yangcli-pro commands are used to initiate RESTCONF operations. The following list summarizes modifications to yangcli-pro to support the new RESTCONF feature.

  • Introduce a new protocol flag - restconf, to distinguish between RESTCONF and NETCONF operations  
yangcli-pro> connect protocol=restconf
  • Handle HTTP/HTTPS communications with RESTCONF server
  • Translate yangcli-pro commands to HTTP Requests and send to RESTCONF Server
  • Parse HTTP Response from RESTCONF Server
  • Handle error during an operation
  • Display RESTCONF related system information


RESTCONF Client uses OpenSSL library to handle secure connection with RESTCONF server. So OpenSSL needs to be installed on machines running RESTCONF Client.

A thin layer of HTTP Generator/Parser is built to handle HTTP request/response, using the underneath OpenSSL connection.


The following programs and libraries are needed for the YumaPro RESTCONF client to work.


The libssl package is needed by the yangcli-pro program, in order to connect to RESTCONF servers using the TLS as a transport and run Apache as a secure server.

This package is called libssl-dev on Ubuntu platforms. This package is not installed by the default Linux installation process.

   

> sudo apt-get install libssl-dev

   


To use RESTCONF yangcli-pro client you need to setup and configure Apache2 WEB server.

1) Refer to Section 4 of the YumaPro SDK Installation Guide for details on how to setup and install Apache2

2) Edit Apache site-available restconf.conf to allow sessions to be open for a longer time. Save and exit.

Otherwise, the Apache will terminate the session after the KeepAliveTimeout.

  

        ## Set if yangcli-pro is used to keep the session alive
        ## Note: these values will overwrite master apache.conf values
        ## if any.
        KeepAlive on
        MaxKeepAliveRequests 1000
        ## Set KeepAliveTimeout to big number to maintain session alive
        KeepAliveTimeout 10

  

3) Now enable the WEB servers:

 

 > sudo a2ensite restconf.conf
 > sudo apachectl restart
 > sudo apachectl -S

 

Now you can access RESTCONF server from the client:


yangcli-pro> connect server=localhost  protocol=restconf user=username password=password transport=tls
@restconf-dev> get-config

    

In the WEB browser:

 

GET http:/restconf-dev/.well-known/host-meta

 

Note: Browsers do not support application/xrd+xml extension. So, either you need to download 

response or use URL interactive tool, such as Poster or Postman.

To see server info. Add a line in the apache.conf and a2enmod status module:

 

ExtendedStatus On

 

Now you can:
 
GET http:/restconf-dev/server-status

 

yangcli-pro commands are used to handle RESTCONF operations. The following table summarizes yangcli-pro common commands to be used for RESTCONF Client and their corresponding RESTCONF operations.


    

yangcli-pro Command
RESTCONF Operation
Notes
create
POST
Create if and only if data does not exist
replace
PUT
Replace if data exists or create if data does not exist
merge
PATCH
Create or update but not delete
insert
POST/PUT/PATCH
HTTP method is decided by the operation parameter

delete/remove

DELETE
Delete data if it exists

sget

GET

Retrieve configuration and operational data with query parameter ?content=all

get-configPOSTInvoke <get-config> operation
any rpc operation
POST
Invoke operation defined with the YANG "rpc" statement