Global Lua Tables

There are multiple global tables containing important data available while writing Lua code for the router.

selection_input

Contains arbitrary, custom fields fed into the router by clients, see API overview for details on how to inject data into this table.

Note that the selection_input table is iterable.

Usage examples:

print(selection_input['some_value'])

-- Iterate over table
if selection_input then
    for k, v in pairs(selection_input) do
        print('here is '..'selection_input!')
        print(k..'='..v)
    end
else
    print('selection_input is nil')
end

session_groups

Defines a mapping from session group name to boolean, indicating whether the session belongs to the session group or not.

Usage examples:

if session_groups.vod then print('vod') else print('not vod') end
if session_groups['vod'] then print('vod') else print('not vod') end

session_count

Provides counters of number of session types per session group. The table uses the structure qoe_score.<session_type>.<session_group>.

Usage examples:

print(session_count.instream.vod)
print(session_count.initial.vod)

qoe_score

Provides the quality of experience score per host per session group. The table uses the structure qoe_score.<host>.<session_group>.

Usage examples:

print(qoe_score.host1.vod)
print(qoe_score.host1.live)

request

Contains data related to the HTTP request between the client and the router.

• request.method
  • Description: HTTP request method.
  • Type: string
  • Example: 'GET', 'POST'
• request.body
  • Description: HTTP request body string.
  • Type: string or nil
  • Example: '{"foo": "bar"}'
• request.major_version
  • Description: Major HTTP version such as x in HTTP/x.1.
  • Type: integer
  • Example: 1
• request.minor_version
  • Description: Minor HTTP version such as x in HTTP/1.x.
  • Type: integer
  • Example: 1
• request.protocol
  • Description: Transfer protocol variant.
  • Type: string
  • Example: 'HTTP', 'HTTPS'
• request.client_ip
  • Description: IP address of the client issuing the request.
  • Type: string
  • Example: '172.16.238.128'
• request.path_with_query_params
  • Description: Full request path including query parameters.
  • Type: string
  • Example: '/mycontent/superman.m3u8?b=y&c=z&a=x'
• request.path
  • Description: Request path without query parameters.
  • Type: string
  • Example: '/mycontent/superman.m3u8'
• request.query_params
  • Description: The query parameter string.
  • Type: string
  • Example: 'b=y&c=z&a=x'
• request.filename
  • Description: The part of the path following the final slash, if any.
  • Type: string
  • Example: 'superman.m3u8'
• request.subnet
  • Description: Subnet of client_ip.
  • Type: string or nil
  • Example: 'all'

session

Contains data related to the current session.

• session.client_ip
  • Description: Alias for request.client_ip. See documentation for table request above.
• session.path_with_query_params
  • Description: Alias for request.path_with_query_params. See documentation for table request above.
• session.path
  • Description: Alias for request.path. See documentation for table request above.
• session.query_params
  • Description: Alias for request.query_params. See documentation for table request above.
• session.filename
  • Description: Alias for request.filename. See documentation for table request above.
• session.subnet
  • Description: Alias for request.subnet. See documentation for table request above.
• session.host
  • Description: ID of the currently selected host for the session.
  • Type: string or nil
  • Example: 'host1'
• session.id
  • Description: ID of the session.
  • Type: string
  • Example: '8eb2c1bdc106-17d2ff-00000000'
• session.session_type
  • Description: Type of the session.
  • Type: string
  • Example: 'initial' or 'instream'. Identical to the value of the Type argument of the session translation function.
• session.is_managed
  • Description: Identifies managed sessions.
  • Type: boolean
  • Example: true if Type/session.session_type is 'instream'

request_headers

Contains the headers from the request between the client and the router, keyed by name.

Usage example:

print(request_headers['User-Agent'])

request_query_params

Contains the query parameters from the request between the client and the router, keyed by name.

Usage example:

print(request_query_params.a)

session_query_params

Alias for metatable request_query_params.

response

Contains data related to the outgoing response apart from the headers.

• response.body
  • Description: HTTP response body string.
  • Type: string or nil
  • Example: '{"foo": "bar"}'
• response.code
  • Description: HTTP response status code.
  • Type: integer
  • Example: 200, 404
• response.text
  • Description: HTTP response status text.
  • Type: string
  • Example: 'OK', 'Not found'
• response.major_version
  • Description: Major HTTP version such as x in HTTP/x.1.
  • Type: integer
  • Example: 1
• response.minor_version
  • Description: Minor HTTP version such as x in HTTP/1.x.
  • Type: integer
  • Example: 1
• response.protocol
  • Description: Transfer protocol variant.
  • Type: string
  • Example: 'HTTP', 'HTTPS'

response_headers

Contains the response headers keyed by name.

Usage example:

print(response_headers['User-Agent'])