experiments/clixon
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

* Restconf stream notification support - two variants.

Browse source 
* Both a "native" stream support and one using nginx/nchan pub/sub.
  * See (apps/restconf/README.md) for details.
* clixon-config YAML file has new revision: 2018-10-21.
This commit is contained in:
Olof hagsand 2018-10-21 22:19:38 +02:00
parent a4e29bcdb7
commit 71eddeaa74
21 changed files with 811 additions and 144 deletions
Download patch file Download diff file Expand all files Collapse all files

80
apps/restconf/README.md
View file

@ -22,14 +22,9 @@ server {
fastcgi_pass unix:/www-data/fastcgi_restconf.sock;
include fastcgi_params;
}
location /stream { # for restconf notifications
fastcgi_pass unix:/www-data/fastcgi_restconf.sock;
include fastcgi_params;
proxy_http_version 1.1;
proxy_set_header Connection "";
}
}
```
Start nginx daemon
```
sudo /etc/init.d nginx start
@ -73,12 +68,77 @@ olof@vandal> curl -G http://127.0.0.1/restconf/data/interfaces/interface/name=et
curl -sX POST -d '{"interfaces":{"interface":{"name":"eth1","type":"eth","enabled":"true"}}}' http://localhost/restconf/data
```
### Nginx Nchan for streams
Restconf notification event streams needs a server-side push
package. Clixon has used Nchan (nchan.io) for this
### Event streams
Download and install nchan, see nchan.io, Install section.
Clixon have two experimental restconf event stream implementations following
RFC8040 Section 6 using SSE. One native and one using Nginx
nchan. The two variants to subscribe to the stream is described in the
next section.
The example [../../example/README.md] creates and EXAMPLE stream.
Set the Clixon configuration options if they differ from default values - if they are OK you do not need to modify them:
```
<CLICON_STREAM_PATH>streams</CLICON_STREAM_PATH>
<CLICON_STREAM_URL>https://example.com</CLICON_STREAM_URL>
<CLICON_STREAM_PUB>http://localhost/pub</CLICON_STREAM_PUB>
```
where
- https://example.com/streams is the public fronting subscription base URL. A specific stream NAME can be accessed as https://example.com/streams/NAME
- http://localhost/pub is the local internal base publish stream.
You access the streams using curl, but they differ slightly in behaviour as described in the following two sections.
### Native event streams
Add the following to extend the nginx configuration file with the following statements:
```
location /streams {
fastcgi_pass unix:/www-data/fastcgi_restconf.sock;
include fastcgi_params;
proxy_http_version 1.1;
proxy_set_header Connection "";
}
```
You access a native stream as follos:
```
curl -H "Accept: text/event-stream" -s -X GET http://localhost/streams/EXAMPLE
curl -H "Accept: text/event-stream" -s -X GET http://localhost/streams/EXAMPLE?start-time=2014-10-25T10%3A02%3A00Z&stop-time=2014-10-25T12%3A31%3A00Z
```
where the first command retrieves only new notifications, and the second receives a range of messages.
### Nginx Nchan streams
Nginx uses pub/sub channels and can be configured in a variety of
ways. The following uses a simple variant with one generic subscription
channel (streams) and one publication channel (pub).
Configure clixon with `--enable-publish` which enables curl code for publishing streams to nchan.
Download and install nchan, see (https://nchan.io/#install).
Add the following to extend the nginx configuration file with the following statements:
```
location ~ /streams/(\w+)$ {
nchan_subscriber;
nchan_channel_id $1; #first capture of the location match
}
location ~ /pub/(\w+)$ {
nchan_publisher;
nchan_channel_id $1; #first capture of the location match
}
```
Access the event stream EXAMPLE using curl:
```
curl -H "Accept: text/event-stream" -s -X GET http://localhost/streams/EXAMPLE
curl -H "Accept: text/event-stream" -H "Last-Event-ID: 1539961709:0" -s -X GET http://localhost/streams/EXAMPLE
```
where the first command retrieves the whole stream history, and the second only retreives the most recent messages given by the ID.
See (https://nchan.io/#eventsource) on more info on how to access an SSE sub endpoint.
### Debugging