The JSON in question is being read in from a RESTful service, and I would like to print it out (to console, although in .gsp would be fine also) for debugging purposes. Groovy 1.3.7 (current as of August 2011) uses Groovy 1.7.8 (which does not have the JsonOutput introduced in 1.8)
Note I am currently reading it in like this, which I am not convinced is the 'grooviest or grail-est' way to do it - perhaps I could take advantage of the converters and pretty printing if done differently? Code sample would be appreciated.
def serviceURL = new URL(theURL)
def json = new JSONObject(serviceURL.text)
println json
You can pretty print JSON with the toString(int indentFactor) method. Example:
def json = new JSONObject()
json.put('foo', 'bar')
json.put('blat', 'greep')
println json
===>{"foo":"bar","blat","greep"}
println json.toString(4)
===>{
"foo": "bar",
"blat": "greep"
}
You can use grails.converters.JSON (which is the most commonly used library for JSON):
In your config.groovy file, add the line to set prettyPrint to true:
grails.converters.default.pretty.print=true
Then, in your controller:
import grails.converters.*
def serviceURL = new URL(theURL)
def json = JSON.parse(serviceURL.text)
println "JSON RESPONSE: ${json.toString()"
If you're in a Grails controller and plan to render the json, then you use something like this (using Grails 2.3.5):
public prettyJson() {
JSON json = ['status': 'OK'] as JSON
json.prettyPrint = true
json.render response
}
I found that solution here: http://www.intelligrape.com/blog/2012/07/16/rendering-json-with-formatting/
Apart from set default pretty print in Config.groovy, JSON's toString() method accepts one boolean parameter. It controls whether pretty print the result or not.
import grails.converters.*
import my.data.*
def accountJson = Account.get(1001) as JSON
println(accountJson.toString(true))
println(accountJson.toString(false))
Tested in Grails 1.3.9.
Related
Seeing an interesting issue, not sure this is to do with parser or the way it suppose to parse. Any help is appreciated
import groovy.json.JsonSlurper
def dMatch = '''[{"match":{"keyId":"A-102161-application"}},{"match":{"keyId":"A-102162-application"}},{"match":{"keyId":"A-102163-application"}},{"match":{"keyId":"A-102164-application"}},{"match":{"keyId":"A-102165-application"}}]'''
println "T1:: List: " + dMatch
def parser = new JsonSlurper()
def exclude = parser.parseText(dMatch)
println "T2:: Obj: " + exclude.toString()
println "----------------------------------------------------"
Output :
T1:: List: [{"match":{"keyId":"A-102161-application"}},
{"match":{"keyId":"A-102162-application"}},
{"match":{"keyId":"A-102163-application"}},
{"match":{"keyId":"A-102164-application"}},
{"match":{"keyId":"A-102165-application"}}]
T2:: Obj: *[[match:[keyId:A-102161-application]],
[match:[keyId:A-102162-application]],
[match:[keyId:A-102163-application]],
[match:[keyId:A-102164-application]],
[match:[keyId:A-102165-application]]]*
The parsed object supposed to be same as the string but all the values were converted as array list of map.
Any idea why this is generating object like this ? When this is sent to camunda it complains
org.camunda.bpm.engine.ProcessEngineException: Cannot serialize object in variable 'exclude': groovy.json.internal.LazyMap
Use JsonSlurperClassic() - it produces standard HashMap that is serializable.
And if you want to convert object back to json use Json output.toJson(obj)
I store a blob of Json in the datastore using JsonProperty.
I don't know the structure of the json data.
I am using endpoints proto datastore in order to retrieve my data.
The probleme is the json property is encoded in base64 and I want a plain json object.
For the example, the json data will be:
{
first: 1,
second: 2
}
My code looks something like:
import endpoints
from google.appengine.ext import ndb
from protorpc import remote
from endpoints_proto_datastore.ndb import EndpointsModel
class Model(EndpointsModel):
data = ndb.JsonProperty()
#endpoints.api(name='myapi', version='v1', description='My Sample API')
class DataEndpoint(remote.Service):
#Model.method(path='mymodel2', http_method='POST',
name='mymodel.insert')
def MyModelInsert(self, my_model):
my_model.data = {"first": 1, "second": 2}
my_model.put()
return my_model
#Model.method(path='mymodel/{entityKey}',
http_method='GET',
name='mymodel.get')
def getMyModel(self, model):
print(model.data)
return model
API = endpoints.api_server([DataEndpoint])
When I call the api for getting a model, I get:
POST /_ah/api/myapi/v1/mymodel2
{
"data": "eyJzZWNvbmQiOiAyLCAiZmlyc3QiOiAxfQ=="
}
where eyJzZWNvbmQiOiAyLCAiZmlyc3QiOiAxfQ== is the base64 encoded of {"second": 2, "first": 1}
And the print statement give me: {u'second': 2, u'first': 1}
So, in the method, I can explore the json blob data as a python dict.
But, in the api call, the data is encoded in base64.
I expeted the api call to give me:
{
'data': {
'second': 2,
'first': 1
}
}
How can I get this result?
After the discussion in the comments of your question, let me share with you a sample code that you can use in order to store a JSON object in Datastore (it will be stored as a string), and later retrieve it in such a way that:
It will show as plain JSON after the API call.
You will be able to parse it again to a Python dict using eval.
I hope I understood correctly your issue, and this helps you with it.
import endpoints
from google.appengine.ext import ndb
from protorpc import remote
from endpoints_proto_datastore.ndb import EndpointsModel
class Sample(EndpointsModel):
column1 = ndb.StringProperty()
column2 = ndb.IntegerProperty()
column3 = ndb.StringProperty()
#endpoints.api(name='myapi', version='v1', description='My Sample API')
class MyApi(remote.Service):
# URL: .../_ah/api/myapi/v1/mymodel - POSTS A NEW ENTITY
#Sample.method(path='mymodel', http_method='GET', name='Sample.insert')
def MyModelInsert(self, my_model):
dict={'first':1, 'second':2}
dict_str=str(dict)
my_model.column1="Year"
my_model.column2=2018
my_model.column3=dict_str
my_model.put()
return my_model
# URL: .../_ah/api/myapi/v1/mymodel/{ID} - RETRIEVES AN ENTITY BY ITS ID
#Sample.method(request_fields=('id',), path='mymodel/{id}', http_method='GET', name='Sample.get')
def MyModelGet(self, my_model):
if not my_model.from_datastore:
raise endpoints.NotFoundException('MyModel not found.')
dict=eval(my_model.column3)
print("This is the Python dict recovered from a string: {}".format(dict))
return my_model
application = endpoints.api_server([MyApi], restricted=False)
I have tested this code using the development server, but it should work the same in production using App Engine with Endpoints and Datastore.
After querying the first endpoint, it will create a new Entity which you will be able to find in Datastore, and which contains a property column3 with your JSON data in string format:
Then, if you use the ID of that entity to retrieve it, in your browser it will show the string without any strange encoding, just plain JSON:
And in the console, you will be able to see that this string can be converted to a Python dict (or also a JSON, using the json module if you prefer):
I hope I have not missed any point of what you want to achieve, but I think all the most important points are covered with this code: a property being a JSON object, store it in Datastore, retrieve it in a readable format, and being able to use it again as JSON/dict.
Update:
I think you should have a look at the list of available Property Types yourself, in order to find which one fits your requirements better. However, as an additional note, I have done a quick test working with a StructuredProperty (a property inside another property), by adding these modifications to the code:
#Define the nested model (your JSON object)
class Structured(EndpointsModel):
first = ndb.IntegerProperty()
second = ndb.IntegerProperty()
#Here I added a new property for simplicity; remember, StackOverflow does not write code for you :)
class Sample(EndpointsModel):
column1 = ndb.StringProperty()
column2 = ndb.IntegerProperty()
column3 = ndb.StringProperty()
column4 = ndb.StructuredProperty(Structured)
#Modify this endpoint definition to add a new property
#Sample.method(request_fields=('id',), path='mymodel/{id}', http_method='GET', name='Sample.get')
def MyModelGet(self, my_model):
if not my_model.from_datastore:
raise endpoints.NotFoundException('MyModel not found.')
#Add the new nested property here
dict=eval(my_model.column3)
my_model.column4=dict
print(json.dumps(my_model.column3))
print("This is the Python dict recovered from a string: {}".format(dict))
return my_model
With these changes, the response of the call to the endpoint looks like:
Now column4 is a JSON object itself (although it is not printed in-line, I do not think that should be a problem.
I hope this helps too. If this is not the exact behavior you want, maybe should play around with the Property Types available, but I do not think there is one type to which you can print a Python dict (or JSON object) without previously converting it to a String.
I try to test a view, I receive a json request from the IPad, the format is:
req = {"custom_decks": [
{
"deck_name": "deck_test",
"updates_last_applied": "1406217357",
"created_date": 1406217380,
"slide_section_ids": [
1
],
"deck_id": 1
}
],
"custom_decks_to_delete": []
}
I checked this in jsonlint and it passed.
I post the req via:
response = self.client.post('/library/api/6.0/user/'+ uuid +
'/store_custom_dec/',content_type='application/json', data=req)
The view return "creation_success": false
The problem is the post method in view doesn't find the key custom_decks.
QueryDict: {u'{"custom_decks": [{"deck_id": 1, "slide_section_ids": [1],
"created_date":1406217380, "deck_name": "deck_test"}],
"custom_decks_to_delete": []}': [u'']}>
The problem is the post method in view doesn't find the key custom_decks.
Because it is converting my dict to QueryDict with one key.
I appreciate all helps.
Thanks
You're posting JSON, which is not the same as form-encoded data. You need to get the value of request.body and deserialize it:
data = json.loads(request.body)
custom_decks = data['custom_decks']
As I was having problems with getting JSON data from HttpRequest directly with the code of the other answer:
data = json.loads(request.body)
custom_decks = data['custom_decks']
error:
the JSON object must be str, not 'bytes'
Here is an update of the other answer for Python version >3:
json_str=((request.body).decode('utf-8'))
json_obj=json.loads(json_str)
Regarding decode('utf-8'), as mention in:
RFC 4627:
"JSON text shall be encoded in Unicode. The default encoding is
UTF-8."
I attached the Python link referred to this specific problem for version >3.
http://bugs.python.org/issue10976
python 3.6 and django 2.0 :
post_json = json.loads(request.body)
custom_decks = post_json.get("custom_decks")
json.loads(s, *, encoding=None,...)
Changed in version 3.6: s can now be of type bytes or bytearray. The input encoding should be UTF-8, UTF-16 or UTF-32.
From python 3.6 NO need request.body.decode('utf-8') .
Since HttpRequest has a read() method loading JSON from request is actually as simple as:
def post(self, request, *args, **kwargs):
import json
data = json.load(request)
return JsonResponse(data=data)
If you put this up as a view, you can test it and it'll echo any JSON you send back to you.
I have code that looks like this:
def client = new groovyx.net.http.RESTClient('myRestFulURL')
def json = client.get(contentType: JSON)
net.sf.json.JSON jsonData = json.data as net.sf.json.JSON
def slurper = new JsonSlurper().parseText(jsonData)
However, it doesn't work! :( The code above gives an error in parseText because the json elements are not quoted. The overriding issue is that the "data" is coming back as a Map, not as real Json. Not shown, but my first attempt, I just passed the parseText(json.data) which gives an error about not being able to parse a HashMap.
So my question is: how do I get JSON returned from the RESTClient to be parsed by JsonSlurper?
The RESTClient class automatically parses the content and it doesn't seem possible to keep it from doing so.
However, if you use HTTPBuilder you can overload the behavior. You want to get the information back as text, but if you only set the contentType as TEXT, it won't work, since the HTTPBuilder uses the contentType parameter of the HTTPBuilder.get() method to determine both the Accept HTTP Header to send, as well was the parsing to do on the object which is returned. In this case, you need application/json in the Accept header, but you want the parsing for TEXT (that is, no parsing).
The way you get around that is to set the Accept header on the HTTPBuilder object before calling get() on it. That overrides the header that would otherwise be set on it. The below code runs for me.
#Grab(group='org.codehaus.groovy.modules.http-builder', module='http-builder', version='0.6')
import static groovyx.net.http.ContentType.TEXT
def client = new groovyx.net.http.HTTPBuilder('myRestFulURL')
client.setHeaders(Accept: 'application/json')
def json = client.get(contentType: TEXT)
def slurper = new groovy.json.JsonSlurper().parse(json)
The type of response from RESTClient will depend on the version of :
org.codehaus.groovy.modules.http-builder:http-builder
For example, with version 0.5.2, i was getting a net.sf.json.JSONObject back.
In version 0.7.1, it now returns a HashMap as per the question's observations.
When it's a map, you can simply access the JSON data using the normal map operations :
def jsonMap = restClientResponse.getData()
def user = jsonMap.get("user")
....
Solution posted by jesseplymale workes for me, too.
HttpBuilder has dependencies to some appache libs,
so to avoid to add this dependencies to your project,
you can take this solution without making use of HttpBuilder:
def jsonSlurperRequest(urlString) {
def url = new URL(urlString)
def connection = (HttpURLConnection)url.openConnection()
connection.setRequestMethod("GET")
connection.setRequestProperty("Accept", "application/json")
connection.setRequestProperty("User-Agent", "Mozilla/5.0")
new JsonSlurper().parse(connection.getInputStream())
}
I have a json object that gets passed into a save function as
{
"markings": {
"headMarkings": "Brindle",
"leftForeMarkings": "",
"rightForeMarkings": "sock",
"leftHindMarkings": "sock",
"rightHindMarkings": "",
"otherMarkings": ""
}
** EDIT **
The system parses it and passes it to my function as a mapping. I don't actually have the JSON, although it wouldn't be difficult to build up the JSON myself, it just seems like overkill
* END EDIT **
The toString() function ends up putting the results into the database as
"[rightForeMarkings:, otherMarkings:, leftForeMarkings:sock, leftHindMarkings:sock, rightHindMarkings:, headMarkings:brindle]"
I then want to save that as a string (fairly easy) by calling
params.markings.toString()
From here, I save the info and return the updated information.
My issue is that since I am storing the object in the DB as a string, I can't seem to get the markings back out as a map (to then be converted to JSON).
I have tried a few different things to no avail, although it is completely possible that I went about something incorrectlywith these...
Eval.me(Item.markings)
evaluate(Item.markings)
Item.markings.toList()
Thanks in advance for the help!
Throwing my tests.
Using JSON converters in Grails, I think this should be the approach: (synonymous to #JamesKleeh and #GrailsGuy)
def json = '''{
"markings": {
"headMarkings": "Brindle",
"leftForeMarkings": "",
"rightForeMarkings": "sock",
"leftHindMarkings": "sock",
"rightHindMarkings": "",
"otherMarkings": ""
}
}'''
def jsonObj = grails.converters.JSON.parse(json)
//This is your JSON object that should be passed in to the method
print jsonObj //[markings:[rightForeMarkings:sock, otherMarkings:, leftForeMarkings:, leftHindMarkings:sock, rightHindMarkings:, headMarkings:Brindle]]
def jsonStr = jsonObj.toString()
//This is the string which should be persisted in db
assert jsonStr == '{"markings":{"rightForeMarkings":"sock","otherMarkings":"","leftForeMarkings":"","leftHindMarkings":"sock","rightHindMarkings":"","headMarkings":"Brindle"}}'
//Get back json obj from json str
def getBackJsobObj = grails.converters.JSON.parse(jsonStr)
assert getBackJsobObj.markings.leftHindMarkings == 'sock'
If I understand correctly, you want to convert a String to a JSON object? You can actually bypass converting it to a map, and parse it directly as a JSON object:
import grails.converters.JSON
def json = JSON.parse(Item.markings)
This will give you your entire JSON object, and then you can just reference the values as you would a map.
Edit #2:
So apparently there is no "safe" way to convert that string back to a map without something custom. I would recommend saving the structure in the database as it originally comes in. If you can do that, then all you would need is JSON.parse()