NAME
coap-client — CoAP Client based on libcoap
SYNOPSIS
coap-client [-a addr] [-b [num,]size] [-e text] [-f file] [-l loss]
[-m method] [-o file] [-p port] [-r] [-s duration]
[-t type] [-v num] [-A type] [-B seconds] [-K interval]
[-N] [-O num,text] [-P addr[:port]] [-T token] [-U]
[[-k key] [-u user]]
[[-c certfile] [-C cafile] [-R root_cafile]] URI
DESCRIPTION
coap-client is a CoAP client to communicate with 6LoWPAN devices via
the protocol CoAP (RFC 7252) using the URI given as argument on the
command line. The URI must have the scheme coap, coap+tcp, coaps or
coaps+tcp. coaps and coaps+tcp are only supported when coap-client is
built with support for secure (D)TLS communication.
If coaps or coap+tcp is being used, provided the CoAP server supports PKI
and is configured with a Certificate and Private Key, the coap-client does not
need to have a Pre-Shared Key (-k) or Certificate (-c) configured.
The URI’s host part may be a DNS name or a literal IP address. Note that, for
IPv6 address references, angle brackets are required (c.f. EXAMPLES).
OPTIONS - General
-
-a addr
-
The local address of the interface that has to be used.
-
-b [num,]size
-
The block size to be used in GET/PUT/POST requests (value must be a
multiple of 16 not larger than 1024 as libcoap uses a fixed maximum
PDU size of 1400 bytes). If num is present, the request
chain will start at block num. When the server includes a Block2
option in its response to a GET request, coap-client will automatically
retrieve the subsequent block from the server until there are no more
outstanding blocks for the requested content.
-
-e text
-
Include text as payload (use percent-encoding for non-ASCII characters).
-
-f file
-
File to send with PUT/POST (use - for STDIN).
-
-l list
-
Fail to send some datagrams specified by a comma separated list of
numbers or number ranges (debugging only).
-
-l loss%
-
Randomly failed to send datagams with the specified probability - 100%
all datagrams, 0% no datagrams (debugging only).
-
-m method
-
The request method for action (get|put|post|delete), default is get.
(Note that the string passed to -m is compared case-insensitive.)
-
-o file
-
A filename to store data retrieved with GET.
-
-p port
-
The port to listen on.
-
-r
-
Use reliable protocol (TCP or TLS).
-
-s duration
-
Subscribe to / observe the resource specified by URI for the given
duration in seconds.
-
-t type
Content format for given resource for PUT/POST. type must be either
a numeric value reflecting a valid CoAP content format or a string
describing a registered format. The following registered content format
descriptors are supported, with alternative shortcuts given in
parentheses:
text/plain (plain)
application/link-format (link, link-format)
application/xml (xml)
application/octet-stream (binary, octet-stream)
application/exi (exi)
application/json (json)
application/cbor (cbor)
-
-v num
-
The verbosity level to use (default 3, maximum is 9). Above 7, there is
increased verbosity in GnuTLS and OpenSSL logging.
-
-A type
-
Accepted media type. type must be either a numeric value reflecting a
valid CoAP content format or a string that specifies a registered format as
described for option -t.
-
-B seconds
-
Break operation after waiting given seconds (default is 90).
-
-K interval
-
Send a ping after interval seconds of inactivity.
If not specified (or 0), keep-alive is disabled (default).
-
-N
-
Send NON-confirmable message. If option -N is not specified, a
confirmable message will be sent.
-
-O num,text
-
Add option num with contents of text to the request. If the text begins
with 0x, then the hex text is converted to binary data.
-
-P addr[:port]
-
Address (and port) for proxy to use (automatically adds Proxy-Uri option
to request).
-
-T token
-
Include the token to the request.
-
-U
-
Never include Uri-Host or Uri-Port options.
OPTIONS - PSK
(If supported by underlying (D)TLS library)
-
-k key
-
Pre-shared key for the specified user (-u option also required).
-
-u user
-
User identity for pre-shared key mode (-k option also required).
OPTIONS - PKI
(If supported by underlying (D)TLS library)
-
-c certfile
-
Use the specified PEM file which contains the CERTIFICATE and PRIVATE
KEY information.
-
-C cafile
-
PEM file containing the CA Certificate that was used to sign the certfile
defined using -c certfile.
This will trigger the validation of the server certificate.
If certfile is self-signed (as defined by -c certfile), then you need to
have on the command line the same filename for both the certfile and cafile
(as in -c certfile -C certfile) to trigger validation.
-
-R root_cafile
-
PEM file containing the set of trusted root CAs that are to be used to
validate the server certificate. The -C cafile does not have to be in
this list and is "trusted" for the verification.
Alternatively, this can point to a directory containing a set of CA PEM files.
EXAMPLES
coap-client coap://coap.me
Query the resource / from server coap.me (using the GET method).
coap-client -m get coap://[::1]/
Query the resource / on localhost using the GET method to get back the
summary defined attributes.
coap-client -m get coap://[::1]/.well-known/core
Query on the resource .well-known/core on localhost to get back a list of
the known resources along with their attribute definitions.
echo -n "mode=on" | coap-client -m put \
coap://[2001:db8:c001:f00d:221:2eff:ff00:2704]:5683/actuators/leds?color=r -f-
Send text mode=on to resource actuators/leds?color=r on the endpoint with
address 2001:db8:c001:f00d:221:2eff:ff00:2704 and port 5683. Note that the
port 5683 is the default port and isn’t actually required in this instance.
coap-client -m put coap://[fec0::3]/ck -T 3a -t binary -f to_upload
Put the contents of file to_upload with content type binary (i.e.
application/octet-stream) into resource ck on fec0::3 using a token of
3a via the PUT method.
FILES
There are no configuration files.
EXIT STATUS
-
0
-
Success
-
1
-
Failure (syntax or usage error; configuration error; document
processing failure; unexpected error)
1.8.13