I have a Ruby on Rails JSON question.
I have what I think is a strange error. I have the following JSON string which I get like this from an external API
test = "[{'domain': 'abc.com'}, {'domain': 'def.com'}, {'domain': 'ghi.com'}]"
Now, I want to convert this string to a hash using:
hash = JSON.parse test
The problem is that it errors with:
JSON::ParserError: 419: unexpected token at '{'domain': 'abc.com'}, {'domain': 'def.com'}, {'domain': 'ghi.com'}]'
The problem now with just replacing ' with " is dangerous if any strings includes ' or ". Anyone have a solution?
It's most likely because this isn't valid JSON. Change your single quotes to double quotes, like so:
test = '[{"domain": "abc.com"}, {"domain": "def.com"}, {"domain": "ghi.com"}]'
An explanation can be found here, and you can validate your JSON here.
You're getting an error because your string isn't valid JSON. In JSON all property names must be double-quoted and string values must also be double-quotes. Single-quotes are never valid.
test = '[{"domain": "abc.com"}, {"domain": "def.com"}, {"domain": "ghi.com"}]'
JSON.parse(test)
# => [ { "domain" => "abc.com" },
# { "domain" => "def.com" },
# { "domain" => "ghi.com" } ]
Using Rails 4 or above, If you want to have symbol keys instead of string keys, you can use deep_symbolize_keys method
hash = JSON.parse(test).deep_symbolize_keys
That's in addition that the real problem was invalid json as MyCah mentioned.
Use this piece of code. you are missing ActiveSupport::JSON
ActiveSupport::JSON.decode json_string
Related
I am trying to format date by iterating through the #data json formatted input shown as below.
#data= JSON.parse(request,symbolize_names: true)[:data]
#data = #data.each{ |key,val| k = Date.parse(key).strftime("%Y %m") }
But this way it is showing error "no implicit conversion of Symbol into String".
Could any one please help?
If you're iterating over a hash where the keys are symbols, then the error is telling you where and what's the problem. In order to parse a date, you must pass a string as argument, and as you haven't converted such object, then you're getting the error.
Try using to_s, to convert the symbol to string:
#data.each do |key, _|
puts Date.parse(key.to_s).strftime '%Y %m'
end
Note if you're inside a block, and you're not going to use the k variable you're creating, then you can avoid creating it, it won't be available outside the block. You're just printing the parsed date.
If you're not going to use the value block variable, then you can omit it.
As pointed #mu, you can omit the symbolize_names: true, and this way the keys will be strings, then, the conversion isn't needed:
require 'date'
require 'json'
request = '{
"data": {
"2017-11-22 00:22:26": "foo" ,
"2017-11-22 00:22:27": "bar"
}
}'
#data = JSON.parse(request)['data']
#data.each do |key, _|
puts Date.parse(key).strftime '%Y %m'
end
request is an approximation to your real data.
I am Having an issue where if a name comes in with a ' or " my JSON parsing fails. I want to know how i can avoid this.
This is my current code:
def create
puts params
##contact = Contact.new(contact_params)
##contact.user = current_user
contactsParam = params[:contacts]
if contactsParam
# contactsParam.each do |contact|
# end
contactValues = contactsParam.map { |c|
puts "dulce!!! : " + c.to_s
json = JSON.parse(c)
result = "('#{json['name']}', '#{json['phone_number']}', '#{json['detail']}', '#{json['image_url']}', '#{json['email']}', '#{json['address']}', '#{json['city']}', '#{json['state']}', '#{json['zipcode']}', '#{json['country']}', #{current_user.id}, now(), now())"
result
}.join(",")
if contactValues.length > 0
ActiveRecord::Base.connection.execute("INSERT INTO contacts (name, phone_number, detail, image_url, email, address, city, state, zipcode, country, user_id, created_at, updated_at) VALUES #{contactValues}")
end
end
here is an example of a JSON String that fails (i added a bunch of random characters to test).
{"name":"Aaacontacttest'/'#"-jgg&$;$/&/#.'sheh","phone_number":",7*#;878545848487849648","detail":"","image_url":"","email":"test#test.com","address":"-/:;()$#""":$;$:$$/!:!/!,!6677bhgv
2017-07-25T20:08:54.614283+00:00 app[web.1]: Hsbsbsbb7788$!","city":"Hehshdbdb","state":"HSSHHSHS$&:$:$","zipcode":"3319)","country":"United States"}
1.
Let's first correct the JSON Object which you gave:
{
"name":"Aaacontacttest'/'#"-jgg&$;$/&/#.'sheh",
"phone_number":",7*#;878545848487849648",
"detail":"",
"image_url":"",
"email":"test#test.com",
"address":"-/:;()$#""":$;$:$$/!:!/!,!6677bhgv2017-07-25T20:08:54.614283+00:00 app[web.1]: Hsbsbsbb7788$!",
"city":"Hehshdbdb",
"state":"HSSHHSHS$&:$:$",
"zipcode":"3319)",
"country":"United States"
}
The problem with this JSON object is, it is not closed properly. If you wanted to use quotes in your object then please use Backslash to omit to close the value of the object.
Let's convert the above invalid JSON Object to valid JSON object first, such ruby avoid syntax error:
{
"name":"Aaacontacttest'/'#\"-jgg&$;$/&/#.'sheh",
"phone_number":",7*#;878545848487849648",
"detail":"",
"image_url":"",
"email":"test#test.com",
"address":"-/:;()$#\"\"\":$;$:$$/!:!/!,!6677bhgv2017-07-25T20:08:54.614283+00:00 app[web.1]: Hsbsbsbb7788$!",
"city":"Hehshdbdb",
"state":"HSSHHSHS$&:$:$",
"zipcode":"3319)",
"country":"United States"
}
What we did over here:
Initial Hash object with the "name" as the key has a value:
"name":"Aaacontacttest'/'#"-jgg&$;$/&/#.'sheh"
Area with bold depicting that you have closed the value with quotes where rest of the Italic character is marked as invalid.
Types of errors which ruby would be raised either "syntax error" or unexpected 'any char', expecting end-of-input
We have introduced backslash in the value to ensure proper closing of the value.
"name":"Aaacontacttest'/'#\"-jgg&$;$/&/#.'sheh"
So where ever you have used quotes in your value please omit them using backslash.
The object which you gave is the normal hash object not a JSON object in case of ruby, as Ruby JSON parser expects the argument to be a string and can’t convert objects like a hash or array.
If you do JSON.generate(hash) you will get the JSON object:
Note: hash if the corrected hashobject.
Adding JSON object over here.
"{\"name\":\"Aaacontacttest'/'#\\"-jgg&$;$/&/#.'sheh\",\"phone_number\":\",7*#;878545848487849648\",\"detail\":\"\",\"image_url\":\"\",\"email\":\"test#test.com\",\"address\":\"-/:;()$#\\"\\"\\":$;$:$$/!:!/!,!6677bhgv2017-07-25T20:08:54.614283+00:00 app[web.1]: Hsbsbsbb7788$!\",\"city\":\"Hehshdbdb\",\"state\":\"HSSHHSHS$&:$:$\",\"zipcode\":\"3319)\",\"country\":\"United States\"}"
If you do JSON.parse(HashObject not JSONobject) the ruby would throw an error:
TypeError: no implicit conversion of Hash into String
Summary:
Correct your hashObject.
Convert you hashObject into the valid JSON object for ruby. If you wanted to generate JSON use JSON.generate(hash) method.
I'm trying to send a JSON API response from my rails app to Dasheroo which expects the following format:
{
my_statistic: { type: 'integer', value: 1, label: 'My Statistic' }
}
However it is not happy with my data structure generated by the following code:
In controller:
def count_foo_members
#foo = Foo.all.count
end
In count_foo_members.json.jbuilder:
json.foo_members do
json.type 'integer'
json.value #foo
json.label 'Foo Members'
end
If I open this route in my browser I can see the following:
{
"foo_members":{"type":"integer","value":1,"label":"Foo Members"}
}
From the results above, the only thing that I can see that could have an effect on the result is the fact that my JSON result has quotation marks around the JSON Key values.
My question thus is: How can I remove these quotation marks in Rails 4 and JBuilder?
JSON.parse(you_response) and you get standart hash.
You cannot remove the quotation marks from the keys. The responsibility is on the consumer (Dasheroo) to parse your JSON string into a JavaScript Object, which will "remove" the quotes from the keys.
Read json-object-with-or-without-quotes for further practical insight.
Lets say I have this Hash:
{
:info => [
{
:from => "Ryan Bates",
:message => "sup bra",
:time => "04:35 AM"
}
]
}
I can call the info array by doing hash[:info].
Now when I turn this into JSON (JSON.generate), and then parse it (JSON.parse), I get this hash:
{
"info" => [
{
"from" => "Ryan Bates",
"message" => "sup bra",
"time" => "04:35 AM"
}
]
}
Now if I use hash[:info] it returns nil, but not if I use hash["info"].
Why is this? And is there anyway to fix this incompatibility (besides using string keys from the start)?
The JSON generator converts symbols to strings because JSON does not support symbols. Since JSON keys are all strings, parsing a JSON document will produce a Ruby hash with string keys by default.
You can tell the parser to use symbols instead of strings by using the symbolize_names option.
Example:
original_hash = {:info => [{:from => "Ryan Bates", :message => "sup bra", :time => "04:35 AM"}]}
serialized = JSON.generate(original_hash)
new_hash = JSON.parse(serialized, {:symbolize_names => true})
new_hash[:info]
#=> [{:from=>"Ryan Bates", :message=>"sup bra", :time=>"04:35 AM"}]
Reference: http://www.ruby-doc.org/stdlib-1.9.3/libdoc/json/rdoc/JSON.html#method-i-parse
In short, no. Think about it this way, storing symbols in JSON is the same as storing strings in JSON. So you cannot possibly distinguish between the two when it comes to parsing the JSON string. You can of course convert the string keys back into symbols, or in fact even build a class to interact with JSON which does this automagically, but I would recommend just using strings.
But, just for the sake of it, here are the answers to this question the previous times it's been asked:
what is the best way to convert a json formatted key value pair to ruby hash with symbol as key?
ActiveSupport::JSON decode hash losing symbols
Or perhaps a HashWithIndifferentAccess
I solved my similar issue with calling the with_indifferent_access method on it
Here I have a json string and we can assign it to variable s
s = "{\"foo\":{\"bar\":\"cool\"}}"
So now I can parse the data with the JSON class and assign it to h
h = JSON.parse(s).with_indifferent_access
This will produce a hash that can accept a string or a symbol as the key
h[:foo]["bar"]
#=> "cool"
Use ActiveSupport::JSON.decode, it will allow you to swap json parsers easier
Use ActiveSupport::JSON.decode(my_json, symbolize_names: true)
This will recursively symbolize all keys in the hash.
(confirmed on ruby 2.0)
It's possible to modify all the keys in a hash to convert them from a string to a symbol:
symbol_hash = Hash[obj.map{ |k,v| [k.to_sym, v] }]
puts symbol_hash[:info]
# => {"from"=>"Ryan Bates", "message"=>"sup bra", "time"=>"04:35 AM"}
Unfortunately that doesn't work for the hash nested inside the array. You can, however, write a little recursive method that converts all hash keys:
def symbolize_keys(obj)
#puts obj.class # Useful for debugging
return obj.collect { |a| symbolize_keys(a) } if obj.is_a?(Array)
return obj unless obj.is_a?(Hash)
return Hash[obj.map{ |k,v| [k.to_sym, symbolize_keys(v)] }]
end
symbol_hash = symbolize_keys(hash)
puts symbol_hash[:info]
# => {:from=>"Ryan Bates", :message=>"sup bra", :time=>"04:35 AM"}
You can't use that option like this
ActiveSupport::JSON.decode(str_json, symbolize_names: true)
In Rails 4.1 or later, ActiveSupport::JSON.decode no longer accepts
an options hash for MultiJSON. MultiJSON reached its end of life and
has been removed.
You can use symbolize_keys to handle it.
Warning: It works only for JSON strings parsed to hash.
ActiveSupport::JSON.decode(str_json).symbolize_keys
This question already has answers here:
Parsing a JSON string in Ruby
(8 answers)
Closed 4 years ago.
I'm looking for a simple way to parse JSON, extract a value and write it into a database in Rails.
Specifically what I'm looking for, is a way to extract shortUrl from the JSON returned from the bit.ly API:
{
"errorCode": 0,
"errorMessage": "",
"results":
{
"http://www.foo.com":
{
"hash": "e5TEd",
"shortKeywordUrl": "",
"shortUrl": "http://bit.ly/1a0p8G",
"userHash": "1a0p8G"
}
},
"statusCode": "OK"
}
And then take that shortUrl and write it into an ActiveRecord object associated with the long URL.
This is one of those things that I can think through entirely in concept and when I sit down to execute I realize I've got a lot to learn.
These answers are a bit dated. Therefore I give you:
hash = JSON.parse string
Rails should automagically load the json module for you, so you don't need to add require 'json'.
Parsing JSON in Rails is quite straightforward:
parsed_json = ActiveSupport::JSON.decode(your_json_string)
Let's suppose, the object you want to associate the shortUrl with is a Site object, which has two attributes - short_url and long_url. Than, to get the shortUrl and associate it with the appropriate Site object, you can do something like:
parsed_json["results"].each do |longUrl, convertedUrl|
site = Site.find_by_long_url(longUrl)
site.short_url = convertedUrl["shortUrl"]
site.save
end
This answer is quite old. pguardiario's got it.
One site to check out is JSON implementation for Ruby. This site offers a gem you can install for a much faster C extension variant.
With the benchmarks given their documentation page they claim that it is 21.500x faster than ActiveSupport::JSON.decode
The code would be the same as Milan Novota's answer with this gem, but the parsing would just be:
parsed_json = JSON(your_json_string)
Here is an update for 2013.
Ruby
Ruby 1.9 has a default JSON gem with C extensions. You can use it with
require 'json'
JSON.parse ''{ "x": "y" }'
# => {"x"=>"y"}
The parse! variant can be used for safe sources. There are also other gems, which may be faster than the default implementation. Please refer to multi_json for the list.
Rails
Modern versions of Rails use multi_json, a gem that automatically uses the fastest JSON gem available. Thus, the recommended way is to use
object = ActiveSupport::JSON.decode json_string
Please refer to ActiveSupport::JSON for more information. In particular, the important line in the method source is
data = MultiJson.load(json, options)
Then in your Gemfile, include the gems you want to use. For example,
group :production do
gem 'oj'
end
This can be done as below, just need to use JSON.parse, then you can traverse through it normally with indices.
#ideally not really needed, but in case if JSON.parse is not identifiable in your module
require 'json'
#Assuming data from bitly api is stored in json_data here
json_data = '{
"errorCode": 0,
"errorMessage": "",
"results":
{
"http://www.foo.com":
{
"hash": "e5TEd",
"shortKeywordUrl": "",
"shortUrl": "http://whateverurl",
"userHash": "1a0p8G"
}
},
"statusCode": "OK"
}'
final_data = JSON.parse(json_data)
puts final_data["results"]["http://www.foo.com"]["shortUrl"]
Ruby's bundled JSON is capable of exhibiting a bit of magic on its own.
If you have a string containing JSON serialized data that you want to parse:
JSON[string_to_parse]
JSON will look at the parameter, see it's a String and try decoding it.
Similarly, if you have a hash or array you want serialized, use:
JSON[array_of_values]
Or:
JSON[hash_of_values]
And JSON will serialize it. You can also use the to_json method if you want to avoid the visual similarity of the [] method.
Here are some examples:
hash_of_values = {'foo' => 1, 'bar' => 2}
array_of_values = [hash_of_values]
JSON[hash_of_values]
# => "{\"foo\":1,\"bar\":2}"
JSON[array_of_values]
# => "[{\"foo\":1,\"bar\":2}]"
string_to_parse = array_of_values.to_json
JSON[string_to_parse]
# => [{"foo"=>1, "bar"=>2}]
If you root around in JSON you might notice it's a subset of YAML, and, actually the YAML parser is what's handling JSON. You can do this too:
require 'yaml'
YAML.load(string_to_parse)
# => [{"foo"=>1, "bar"=>2}]
If your app is parsing both YAML and JSON, you can let YAML handle both flavors of serialized data.
require 'json'
out=JSON.parse(input)
This will return a Hash
require 'json'
hash = JSON.parse string
work with the hash and do what you want to do.
The Oj gem (https://github.com/ohler55/oj) should work. It's simple and fast.
http://www.ohler.com/oj/#Simple_JSON_Writing_and_Parsing_Example
require 'oj'
h = { 'one' => 1, 'array' => [ true, false ] }
json = Oj.dump(h)
# json =
# {
# "one":1,
# "array":[
# true,
# false
# ]
# }
h2 = Oj.load(json)
puts "Same? #{h == h2}"
# true
The Oj gem won't work for JRuby. For JRuby this (https://github.com/ralfstx/minimal-json) or this (https://github.com/clojure/data.json) may be good options.
RUBY is case sensitive.
require 'json' # json must be lower case
JSON.parse(<json object>)
for example
JSON.parse(response.body) # JSON must be all upper-case
Here's what I would do:
json = "{\"errorCode\":0,\"errorMessage\":\"\",\"results\":{\"http://www.foo.com\":{\"hash\":\"e5TEd\",\"shortKeywordUrl\":\"\",\"shortUrl\":\"http://b.i.t.ly/1a0p8G\",\"userHash\":\"1a0p8G\"}},\"statusCode\":\"OK\"}"
hash = JSON.parse(json)
results = hash[:results]
If you know the source url then you can use:
source_url = "http://www.foo.com".to_sym
results.fetch(source_url)[:shortUrl]
=> "http://b.i.t.ly/1a0p8G"
If you don't know the key for the source url you can do the following:
results.fetch(results.keys[0])[:shortUrl]
=> "http://b.i.t.ly/1a0p8G"
If you're not wanting to lookup keys using symbols, you can convert the keys in the hash to strings:
results = json[:results].stringify_keys
results.fetch(results.keys[0])["shortUrl"]
=> "http://b.i.t.ly/1a0p8G"
If you're concerned the JSON structure might change you could build a simple JSON Schema and validate the JSON before attempting to access keys. This would provide a guard.
NOTE: Had to mangle the bit.ly url because of posting rules.
You can try something like this:
def details_to_json
{
:id => self.id,
:credit_period_type => self.credit_period_type,
:credit_payment_period => self.credit_payment_period,
}.to_json
end