ftpfilez

Really simple FTPS client - only put, get and delete.

This client is used in combination with filezcache and zotonic.

Distinction with other FTPS clients is:

• Only get, put and delete are supported
• put of files and/or binaries
• get with optional streaming function, to be able to stream to the filezcache
• simple jobs queue, using the 'jobs' scheduler
• missing directories in the target path are automatically created

NOTA BENE This client only supports FTPS, you really shouldn't use plain FTP anymore.

Example

rebar3 shell
===> Verifying dependencies...
===> Analyzing applications...
===> Compiling ftpfilez
Erlang/OTP 23 [erts-11.1] [source] [64-bit] [smp:12:12] [ds:12:12:10] [async-threads:1] [hipe]

Eshell V11.1  (abort with ^G)
1> application:ensure_all_started(ftpfilez).
{ok,[jobs,ftpfilez]}
2> Cfg = #{ username => <<"anonymous">>, password => <<"test@example.com">> }.
{<<"anonymous">>, <<"test@example.com">>}
3> ftpfilez:put(Cfg, <<"ftps://ftp.example.com/LICENSE">>, {filename, "LICENSE"}).
ok
4> ftpfilez:stream(Cfg, <<"ftps://ftp.example.com/LICENSE">>, fun(X) -> io:format("!! ~p~n", [X]) end).
!! stream_start
!! <<"\n    Apache License\n", ...>>
!! eof
5> ftpfilez:delete(Cfg, <<"ftps://ftp.example.com/LICENSE">>).
ok

Request Queue

Requests can be queued. They will be placed in a supervisor and scheduled using https://github.com/uwiger/jobs The current scheduler restricts the number of parallel FTP requests. The default maximum is 4. This is because many FTP servers have their maximum number of parallel connections set 10. Assuming that more than one ftpfilez client is connecting to the FTP server, we have set the default limit to just less than half of that.

The get, put and delete requests can be queued. A function or pid can be given as a callback for the job result. The stream command can’t be queued: it is already running asynchronously.

Example:

6> {ok, ReqId, JobPid} = ftpfilez:queue_put(Cfg, <<"ftps://ftp.example.com/LICENSE">>, {filename, "LICENSE"}, fun(ReqId,Result) -> io:format("!! ~p~n", [ Result ]) end).
{ok,#Ref<0.0.0.3684>,<0.854.0>}

The returned JobPid is the pid of the process in the ftpfilez queue supervisor. The callback can be a function (arity 2), {M,F,A} or a pid.

If the callback is a pid then it will receive the message {ftpfilez_done, ReqId, Result}.