Plug v1.6.4 Plug.Upload View Source
A server (a GenServer
specifically) that manages uploaded files.
Uploaded files are stored in a temporary directory and removed from that directory after the process that requested the file dies.
During the request, files are represented with
a Plug.Upload
struct that contains three fields:
:path
- the path to the uploaded file on the filesystem:content_type
- the content type of the uploaded file:filename
- the filename of the uploaded file given in the request
Note: as mentioned in the documentation for Plug.Parsers
, the :plug
application has to be started in order to upload files and use the
Plug.Upload
module.
Link to this section Summary
Functions
Returns a specification to start this module under a supervisor
Invoked when the server is started. start_link/3
or start/3
will
block until it returns
Requests a random file to be created in the upload directory with the given prefix. Raises on failure
Requests a random file to be created in the upload directory with the given prefix
Starts the upload handling server
Link to this section Types
Link to this section Functions
Returns a specification to start this module under a supervisor.
See Supervisor
.
Invoked when the server is started. start_link/3
or start/3
will
block until it returns.
args
is the argument term (second argument) passed to start_link/3
.
Returning {:ok, state}
will cause start_link/3
to return
{:ok, pid}
and the process to enter its loop.
Returning {:ok, state, timeout}
is similar to {:ok, state}
except handle_info(:timeout, state)
will be called after timeout
milliseconds if no messages are received within the timeout.
Returning {:ok, state, :hibernate}
is similar to {:ok, state}
except the process is hibernated before entering the loop. See
c:handle_call/3
for more information on hibernation.
Returning {:ok, state, {:continue, continue}}
is similar to
{:ok, state}
except that immediately after entering the loop
the c:handle_continue/2
callback will be invoked with the value
continue
as first argument.
Returning :ignore
will cause start_link/3
to return :ignore
and
the process will exit normally without entering the loop or calling
c:terminate/2
. If used when part of a supervision tree the parent
supervisor will not fail to start nor immediately try to restart the
GenServer
. The remainder of the supervision tree will be started
and so the GenServer
should not be required by other processes.
It can be started later with Supervisor.restart_child/2
as the child
specification is saved in the parent supervisor. The main use cases for
this are:
- The
GenServer
is disabled by configuration but might be enabled later. - An error occurred and it will be handled by a different mechanism than the
Supervisor
. Likely this approach involves callingSupervisor.restart_child/2
after a delay to attempt a restart.
Returning {:stop, reason}
will cause start_link/3
to return
{:error, reason}
and the process to exit with reason reason
without
entering the loop or calling c:terminate/2
.
Callback implementation for GenServer.init/1
.
Requests a random file to be created in the upload directory with the given prefix. Raises on failure.
random_file(binary()) :: {:ok, binary()} | {:too_many_attempts, binary(), pos_integer()} | {:no_tmp, [binary()]}
Requests a random file to be created in the upload directory with the given prefix.
Starts the upload handling server.