Python Array JSON (dumps) -


google app engine, python27

i trying encode python array of strings json string send client. created working solution, requires me manually create string version of array , call dumps on python, don't believe should necessary:

def get_json(cls):   name_query = cls.query()   array_string = "["   index = 1   name in name_query:       array_string += '"' + name.key.id() + '"'       if index < name_query.count():           array_string += ", "       index += 1   array_string += "]"   return json.dumps(array_string)  >> "[\"billy\", \"bob\"]"

for second attempt, tried calling "dumps" on python array, believe should working solution; instead, have call dumps twice:

# (bad output) def get_json(cls):   name_query = cls.query()   name_array = []           name in name_query:       name_array.append(name.key.id())   return json.dumps(name_array)    >> ["billy", "bob"]  # (working output) def get_json(cls):   name_query = cls.query()   name_array = []           name in name_query:       name_array.append(name.key.id())   return json.dumps(json.dumps(name_array)))    >> "[\"billy\", \"bob\"]"

even though have working solution, there better way , why calling dumps on python array not give correct output?

the first function working fine; it's outputting valid json string. think confusion it's not surrounded in double-quotes, that's because you're printing output of function.

it's returning string containing json list, not python list object:

>>> def get_json(): ...  x = ["billy", "bob"] ...  return json.dumps(x) ...  >>> print get_json() ["billy", "bob"] >>> print repr(get_json()) '["billy", "bob"]'  # it's string, not list >>> type(get_json()) <type 'str'>  # see? type str

when call json.dumps twice, you're wrapping python string returned first json.dumps call in double-quotes, , double-quotes inside array escaped, because they're embedded in 1 big json string now, instead of being used quotes around json strings inside json array.

>>> print repr(json.dumps(get_json())) '"[\\"billy\\", \\"bob\\"]"'

Comments

Post a Comment

Popular posts from this blog

javascript - RequestAnimationFrame not working when exiting fullscreen switching space on Safari -

request animation frame stops working when exiting fullscreen clicking on original space's safari window. fine if fullscreen mode canceled escape key or calling cancelfullscreen(). steps reproduce: open https://dl.dropboxusercontent.com/u/769042/prezi/safari-fullscreen.html click "draw raf", kittie appears click "fullscreen", go fullscreen click "draw raf", kittie appears go space original safari was, showing "click exit fullscreen mode", click anywhere, out fullscreen click "draw raf", nothing happens what handling click calling: window.requestanimationframe(draw); which draws on canvas context: function draw() { ctx.drawimage(img, math.random()*500|0, math.random()*400|0, 100, 100); } i checked .hidden , .visibilitystate, updated correctly. tested on osx 10.9.3, safari 7.0.4 (9537.76.4). has workaround/solution other switching old settimeout? this sounds webkit bug 88940 : using reque...
Read more

jsf - How to ajax update an item in the footer of a PrimeFaces dataTable? -

this visual of table have: +---------+------------+-------------------+ | header1 | header2 | header3 | +---------+------------+-------------------+ | row | input | calc'ed output | | row b | input b | calc'ed output b | | etc.. | etc.. | etc.. | +---------+------------+-------------------+ | total: total calc'ed output | +------------------------------------------+ and stripped-down code: <p:datatable id="mytable" value="#{mybean.somelist}" var="currentitem"> <p:column headertext="header1"> <h:outputtext value="#{currentitem.name}" /> </p:column> <p:column headertext="header2"> <pe:inputnumber value="#{currentitem.inputval}"> <p:ajax event="change" listener="#{mybean.changelistener}" update="outputval outputtotal...
Read more

jquery - Keeping Kendo Datepicker in min/max range -

when user types type in date outside of range, we're trying ensure date gets changed closest min/max. text displayed in date picker not change though thought script changing value() @(html.kendo() .datepickerfor(x => x.dob) .max(new datetime(datetime.now.addyears(-18).year, datetime.now.addyears(-18).month, datetime.now.addyears(-18).day)) .min(new datetime(datetime.now.addyears(-70).year, datetime.now.addyears(-70).month, datetime.now.addyears(-70).day)) .events(e=>e.change("ondobchange")) .htmlattributes(new { required = "required", ng_model = "model.dob" })) <p ng-show="validatestate.submitted && frmmain.dob.$invalid" class="help-block">please select</p> <script> function ondobchange(e) { var d...
Read more