FreeSWITCH          




Page tree
Skip to end of metadata
Go to start of metadata

About

mod_http_cache allows one to make an HTTP GET request to cache a document and HTTP PUT to store a document. The primary use case is to download and cache audio files from a web server.

mod_http_cache will only respect the max-age cache-control directive to determine when a cached file becomes stale. Use http_remove_cache <url> to force an update if you know the source file on the server is newer than the cached file.

mod_http_cache offers the http_cache:// read and write file interfaces. See these examples for usage.

mod_http_cache offers the http:// and https:// read and write file interfaces if the "enable-file-formats" param is set to true. DO NOT LOAD mod_httapi IF YOU USE THIS PARAM.

mod_http_cache supports GET/PUT to Amazon S3 private buckets and (on FreeSWITCH later than 1.6) Microsoft's Azure Blob Service. See configuration below.

mod_httapi is also available which offers an HTTP read/write file interface.

 Click here to expand Table of Contents

Installing

To use mod_http_cache:

Tell FreeSWITCH to compile in this module by editing modules.conf in /usr/src/freeswitch/trunk and adding:

Now go recompile FreeSWITCH.

Tell FreeSWITCH to actually use the module when running by adding the module to modules.conf.xml in /usr/local/freeswitch/conf/autoload_configs:

 

For HTTPS support, grab the latest CA certs from http://curl.haxx.se/ca/cacert.pem and install in /usr/local/freeswitch/conf. An older copy is also available in freeswitch/src/mod/applications/mod_http_cache/conf/cacert.pem.

Configuration

The conf/autoload_configs/http_cache.conf.xml file contains the configuration.

http_cache.conf.xml

API

http_prefetch

Download a URL to the cache in a background thread. Does not wait for the download to finish.

http_get

Download a document to the cache. Returns the name of the cached file suitable for use by FreeSWITCH APPs or "-ERR" on error:

http_tryget

Same as http_get except if the document is missing from the cache or stale, "-ERR download" is returned. i.e. this API call checks the cache only. "-ERR" is returned on all other errors:

http_put

PUT a file. This can be used to PUT a file like a session recording to a webserver:

http_remove_cache

Invalidate a cached file, typically when the source file has been updated. This will force the updated file to be downloaded into the cache.


http_clear_cache

Empty the cache:

Examples

Playback

Play a .wav file hosted by a webserver.

http_prefetch

While this example below will work, it is probably best to download all the .wav files needed by a call in a background thread early in the call using http_prefetch. Subsequent calls to http_get will then just grab the cached file. That way, delays in downloading will be less likely to cause pauses in playback.


enable-file-formats=false

enable-file-formats=false


enable-file-formats=true

enable-file-formats=true


refresh=true

Force download of source file, for example if the file on the server has been updated and the cached file is now invalid.

Refresh


Recording

How to record a .wav file to a webserver

mod_http_cache can record using the http/https/http_cache file formats. The file is PUT when the recording is completed and the file is closed. 

enable-file-formats=false

enable-file-formats=false

 

enable-file-formats=true

enable-file-formats=true