Python UDP socket resend data if no data recieved -


i want send data sensor , if python script doesn't receive data want receive function timeout , resend data.

def subscribe():    udp_ip = "192.168.1.166"    udp_port = 10000    message = '6864001e636caccf2393730420202020202004739323cfac202020202020'.decode('hex')    print "udp target ip:", udp_ip    print "udp target port:", udp_port    print "message:", message    sock = socket.socket(socket.af_inet, socket.sock_dgram)    sock.sendto(message, (udp_ip, udp_port))    recieve_data = recieve()    if recieve_data == subscribe_recieve_on or recieve_data == subscribe_recieve_off:        logging.info('subscribition light successful')    else:        logging.info('subscribition light unsuccessful')  def recieve():    udp_ip = "192.168.1.118"    udp_port = 10000    sock = socket.socket(socket.af_inet, socket.sock_dgram) # udp        sock.bind((udp_ip, udp_port))    data, addr = sock.recvfrom(1024)    return data.encode('hex')  subscribe()

at moment gets stuck in receive function if doesn't receive data:

data, addr = sock.recvfrom(1024)

however want timeout after e.g. 2 seconds , rerun subscribe() function.

i've tried using while true statement timeout , try/exception port in use when closing port. feel way messy.

any ideas appreciated.

you "currently in use" exception because recreating sockets every time call either of functions, without closing them first.

try creating sockets beforehand. response might come before receiving socket created in case packet going rejected.

then should try sendto-recvfrom calls in loop.

also either need set timeout settimeout on receiving socket not blocked catch timeout exception or use polling mechanism select or poll check whether have received data.


Comments

Post a Comment

Popular posts from this blog

jOOQ update returning clause with Oracle -

according http://www.jooq.org/doc/3.8/manual/sql-building/sql-statements/update-statement/ jooq doesn't support returning clause in update statements databases except firebird , postgres. does know, still correct oracle jooq? according oracle's documentation, oracle db supports returning clase delete, insert, or update statements. incorrect manual you're right - manual wrong , should fixed: https://github.com/jooq/jooq/issues/5470 single row update returning jooq 3.8 added support single row update .. returning statements. internally, uses callablestatement , pl/sql block of form: begin update "my_table" set "my_table"."column" = 'xyz' "my_table"."id" = 1 returning "my_table"."id", "my_table"."column" ?, ?; ? := sql%rowcount; end; the relevant issue is: https://github.com/jooq/jooq/issues/5190 multi row update returning a...
Read more

java - Warning equals/hashCode on @Data annotation lombok with inheritance -

i have entity inherits other. on other hand, i'm using lombok project reduce boilerplate code, put @data annotation. annotation @data inheritance produces next warning: generating equals/hashcode implementation without call superclass, though class not extend java.lang.object. if intentional, add '@equalsandhashcode(callsuper=false)' type. is advisable add annotation @equalsandhashcode (callsuper = true) or @equalsandhashcode (callsuper = false) ? if not added, 1 callsuper=false or callsuper=true ? the default value false . 1 if don't specify , ignore warning. yes, recommended add @equalsandhashcode annotation on @data annotated classes extend else object. cannot tell if need true or false , depends on class hierarchy, , need examined on case-by-case basis. however, project or package, can configure in lombok.config call super methods if not direct subclass of object. lombok.equalsandhashcode.callsuper = call for configuration system ...
Read more

java - BasicPathUsageException: Cannot join to attribute of basic type -

i using java 8 jpa (hibernate 5.2.1). have clause works perfectly, until introduce clause make use foreign key table values too. i getting following error: basicpathusageexception: cannot join attribute of basic type i think problem related fact have join table, , not sure how create join using join table. employee - employee_category - category model (employee.java): @manytomany(cascade = cascadetype.all, fetch=fetchtype.eager) @jointable ( name="employee_category", joincolumns={ @joincolumn(name="emp_id", referencedcolumnname="id") }, inversejoincolumns={ @joincolumn(name="cat_id", referencedcolumnname="id") } ) private set<category> categories; model (category.java): @id private string id; jpa when introduce following code, fails error above (i think problem new piece of code): join<t, category> category = from.join("id"); predicates.add(criteriabuilder.like(category....
Read more