Sourceval get :
?meth:string ->
?headers:(string * string) list ->
?msg:string ->
string ->
((string, int * string option) result -> unit) ->
unit Sourceval post :
?meth:string ->
?content_type:string ->
?content:string ->
?headers:(string * string) list ->
?msg:string ->
string ->
((string, int * string option) result -> unit) ->
unit