Vetalll Vetalll - 1 month ago 5
Python Question

Python json, unnecessary slashes

I am creating a simple server side app, i use built in module "json" for creating an answer to client.

if isinstance(obj, (list, tuple)):
return json.dumps({key: [o.to_json() for o in obj if
isinstance(o, JsonAble)]}, ensure_ascii=False)


where my class which in list

class ArtistSearchResult(JsonAble):

def to_json(self):
return json.dumps({'name': self.name, 'descr': self.descr,
"url": self.url, 'genres': self.genres},
allow_nan=False, ensure_ascii=False)


It works, but in response i have an unnecessary slashes:

{"responce": ["{\"url\": \"/music/Lindsey+Buckingham\", \"genres\": [\"singer-songwriter\"], \"name\": \"Lindsey Buckingham\", \"descr\": \"Lindsey Adams Buckingham (born October 3, 1949) is an American guitarist, singer, composer and producer, most notable for being the...…read more\"}", "{\"url\": \"/music/Lindsey+Stirling\", \"genres\": [\"violin\"], \"name\": \"Lindsey Stirling\", \"descr\": \"Lindsey Stirling (b. 21 September 1986 in Orange County, California) is a violinist, dancer and composer based in Utah.…read more\"}", "{\"url\": \"/music/Graham+Lindsey\", \"genres\": [\"alt-country\"], \"name\": \"Graham Lindsey\", \"descr\": \"Graham Lindsey is a performing songwriter, an americana singer of subtle, stark ballads and waltzes of love and murder. A member of the...…read more\"}", "{\"url\": \"/music/Lindsey+Haun\", \"genres\": [\"country\"], \"name\": \"Lindsey Haun\", \"descr\": \"Lindsey Haun (born November 21, 1984 in Los Angeles, California) is an American actress and country music singer. Haun started acting...…read more\"}", "{\"url\": \"/music/Ryan+Lindsey\", \"genres\": [\"oklahoma\"], \"name\": \"Ryan Lindsey\", \"descr\": \"Ryan Lindsey is a singer-songwriter based in Norman, Oklahoma. He started as an entertainer early on making movies with his brothers and...…read more\"}", "{\"url\": \"/music/+noredirect/Tyler+Ward+&+Lindsey+Stirling\", \"genres\": [\"pop\"], \"name\": \"Tyler Ward & Lindsey Stirling\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Megan+Nicole+&+Lindsey+Stirling\", \"genres\": [\"pop\"], \"name\": \"Megan Nicole & Lindsey Stirling\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Lindsey+Pavao\", \"genres\": [\"the voice\"], \"name\": \"Lindsey Pavao\", \"descr\": \"Lindsey Pavao is an American singer from Sacramento, California. She was one of the contestants of NBC singing reality show, The Voice...…read more\"}", "{\"url\": \"/music/Steve+Forte+Rio+Feat.+Lindsey+Ray\", \"genres\": [\"house\"], \"name\": \"Steve Forte Rio Feat. Lindsey Ray\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Peter+Hollens+&+Lindsey+Stirling\", \"genres\": [\"ost\"], \"name\": \"Peter Hollens & Lindsey Stirling\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Steve+Forte+Rio%2FLindsey+Ray\", \"genres\": [], \"name\": \"Steve Forte Rio/Lindsey Ray\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Kurt+Schneider+&+Aim%C3%A9e+Proal+&+Lindsey+Stirling\", \"genres\": [\"female vocalist\"], \"name\": \"Kurt Schneider & Aimée Proal & Lindsey…\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Eppic+feat.+Lindsey+Stirling\", \"genres\": [\"instrumental\"], \"name\": \"Eppic feat. Lindsey Stirling\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Lindsey+Stirling+and+Shaun+Barrowes\", \"genres\": [\"instrumental\"], \"name\": \"Lindsey Stirling and Shaun Barrowes\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Lindsey+Lin%27s\", \"genres\": [\"zouk\"], \"name\": \"Lindsey Lin's\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Lindsey+Ray\", \"genres\": [\"pop\"], \"name\": \"Lindsey Ray\", \"descr\": \"At the tender age of five, Lindsey Ray declared to her family, \\\"When I grow up, I'm going to be a singer.\\\" The passion was in...…read more\"}", "{\"url\": \"/music/Tyler+Ward,+Chester+See+&+Lindsey+Stirling\", \"genres\": [\"pop\"], \"name\": \"Tyler Ward, Chester See & Lindsey…\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Patrick+Lindsey\", \"genres\": [\"techno\"], \"name\": \"Patrick Lindsey\", \"descr\": \"Born in Bad Nauheim near Frankfurt, Patrick Lindsey was one of the founders of the much respected label Kanzleramt in 1993. Later Patrick...…read more\"}", "{\"url\": \"/music/Steve+Forte+Rio;Lindsey+Ray\", \"genres\": [], \"name\": \"Steve Forte Rio;Lindsey Ray\", \"descr\": \"We don’t have a description for this artist yet\"}", "{\"url\": \"/music/Lindsey+Woolsey\", \"genres\": [\"pop songs\"], \"name\": \"Lindsey Woolsey\", \"descr\": \"Lindsey Woolsey are Elle Osborne and Melanie Wilson. They met in a hotel lobby in East London in 2004 and have been collaborating with...…read more\"}"]}


Why they emerge in my answer?

Answer

Your to_json()method returns a string that contains JSON. json.dumps() then goes on to escape the quotes, which are a special character in JSON.

Your to_json() should return a dict, which can then be encoded by json.dumps()

class ArtistSearchResult(JsonAble):

    def to_json_dict(self):
        return {'name': self.name, 'descr': self.descr,
                'url': self.url, 'genres': self.genres}

A better, but more complicated way would probably be to write a custom JSONEncoder subclass.