How to parse uri queries with GET in SMCP

[Shantanoo Desai]

Hi,

I have been looking around and wanted to know are there implementations for parsing URI queries using GET in SMCP.

in a nutshell, something like:

   

smcpctl get coap://localhost:5683/hash?param=file

this is a just a dumb example where I wish to use a simple md5 hash check on the above mentioned `file` parameter. A rough logic is if the `file` exists do a simple md5 hash and return it using GET.

I think if smcp-variable_handler.h and .c are the files one should be working with? and is there any example in the repo?


thanks,

shan

[Paulo Leonardo]

Shantanoo,

do you mean parsing the URI on "server" endpoint?

I have put this gist: https://gist.github.com/paulobrizolara/e6a190d9310635260f31947753867d3f

with part of a code i was working on.

It shows how to load a Url using smcp.
Note: the code uses c++11.

Note2: i did not tested this code isolated, but i hope it is working. :)

Also, it does not handle the query part (i.e.: "?param=file").

But since coap stores it as an option (see here in the RFC), then it should be easy to adapt the code.

Check for the 'COAP_OPTION_URI_QUERY' option in 'smcp/coap.h'

Paulo

 

[Robert Quattlebaum]

Yes, queries on URIs should be parsed and passed along with the GET request (as in, this is already implemented), but I'm a little confused by your question.

smcp-variable_handler is used for easily implementing simple variable-like resources that you can get and set. (like "light-state", "temperature", etc)

But I'm not sure what that has to do with URI query parsing.

-- RQ

[Robert Quattlebaum]

Note that there is a an already-implemented similar mechanism in smcp:

//! Get a string representation of the destination path in the inbound packet.
SMCP_API_EXTERN char* smcp_inbound_get_path(char* where, uint8_t flags);

Where the flags are:

#define SMCP_GET_PATH_REMAINING (1<<0)
#define SMCP_GET_PATH_LEADING_SLASH (1<<1)
#define SMCP_GET_PATH_INCLUDE_QUERY (1<<2)

So you could easily use this to reconstruct the part of the URI after the host.

-- RQ