HA PROXY LOG ALL CUSTOM HEADERS

Help!
1 
log         127.0.0.1:514 local1 notice
log         127.0.0.1:514 local2

frontend myservice
bind *:8690
mode http
option httplog
capture request header MyId len 500
log-format %ci:%cp\ [id=%ID]\ [%t]\ %f\ %b/%s\ %Tq/%Tw/%Tc/%Tr/%Tt\ %ST\ %B\ %CC\ %CS\ %tsc\ %ac/%fc/%bc/%sc/%rc\ %sq/%bq\ {%hrl}\ {%hsl}\ %{+Q}r
log 127.0.0.1 local1
default_backend myservice

backend myservice
mode http
option httplog
balance roundrobin
server myservice-01 127.0.0.1:18190 check weight 1
server myservice-02 127.0.0.1:28190 check weight 10

Above is the settings of my HA Proxy config. Using this, i am able to capture custom header named MyId. However is there any way using which i can capture all custom headers.

Thanks