parse_root_in_json true, but not in active_model_serializers_format or json_api_format problems

[fractaledmind]

When moving a project from ActiveResource to her, my team and I came across a problem. The API we are using (which is being built by our team for an enterprise application) wraps the JSON response in a model name (e.g. GET /api/v1/accounts -> {"accounts":[<data>]}, or GET /api/v1/accounts/2 -> {"account":{<data>}}). This API, however, is not using ActiveModelSerializer to generate the responses (it uses JBuilder templates, FWIW). When creating the models to be backed by her, we simply had:

class Account
  include Her::Model
  parse_root_in_json true
end

Attempting to access that model threw an error, however: Undefined method '.keys' for #<Array>. In debugging this issue, I found that the problem lied in the extract_array method in the parse.rb file:

def extract_array(request_data)
  if request_data[:data].is_a?(Hash) && (active_model_serializers_format? || json_api_format?)
    request_data[:data][pluralized_parsed_root_element]
  else
    request_data[:data]
  end
end

The issue is that our request_data wasn't passing the first if clause, since I didn't state that the format was one of those two options, although the response was a Hash. This method thus simply returned the hash response (i.e. accounts: {<data>}), instead of accessing the nested data.

There are obviously numerous simple fixes (remove the second half of the if check, move that second half into a new nested if check, if Hash, try to access request_data[:data][pluralized_parsed_root_element] and handle possible errors, etc), but I don't presume to understand precisely what your large scale project decisions are that led to this particular implementation, thus I haven't yet put in a Pull Request.

Hopefully, this is clear enough to display the issue that my team and I had. If not, let me know what else would prove valuable to you.

Love the project!

stephen

[hubert]

Hi Stephen,

Thanks for writing in with your issue. I think the best course of action to
your problem would be to specify that the api use the
active_model_serializers format. I believe that should interpret the root
keys for your data correctly.

The naming is probably a bit misleading since it indicates that one should
specify the format to consume an API that is produced by
active_model_serializers when what is really specifying is what is expected
for the root keys.

Let me know if this fixes your issue.

Thanks!

On Wed, Oct 21, 2015 at 8:55 AM, Stephen Margheim [email protected]
wrote:

When moving a project from ActiveResource to her, my team and I came
across a problem. The API we are using (which is being built by our team
for an enterprise application) wraps the JSON response in a model name
(e.g. GET /api/v1/accounts -> {"accounts":[]}, or GET
/api/v1/accounts/2 -> {"account":{}}). This API, however, is not
using ActiveModelSerializer to generate the responses (it uses JBuilder
templates, FWIW). When creating the models to be backed by her, we simply
had:

class Account
include Her::Model
parse_root_in_json true
end

Attempting to access that model threw an error, however: Undefined method
'.keys' for #. In debugging this issue, I found that the problem
lied in the extract_array method in the parse.rb file:

def extract_array(request_data)
if request_data[:data].is_a?(Hash) && (active_model_serializers_format? || json_api_format?)
request_data[:data][pluralized_parsed_root_element]
else
request_data[:data]
end
end

The issue is that our request_data wasn't passing the first if clause,
since I didn't state that the format was one of those two options, although
the response was a Hash. This method thus simply returned the hash
response (i.e. accounts: {}), instead of accessing the nested data.

There are obviously numerous simple fixes (remove the second half of the
if check, move that second half into a new nested if check, if Hash, try
to access request_data[:data][pluralized_parsed_root_element] and handle
possible errors, etc), but I don't presume to understand precisely what
your large scale project decisions are that led to this particular
implementation, thus I haven't yet put in a Pull Request.

Hopefully, this is clear enough to display the issue that my team and I
had. If not, let me know what else would prove valuable to you.

Love the project!

stephen

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#380.

[fractaledmind]

@hubert That does fix my problem, but I'm not certain it's the best general fix. What is the point of parse_root_in_json true if it doesn't actually parse the root key without that format specified? Would it not be possible to add another else path to the extract_array function for the situation where parse_root_in_json is true, but no format is specified? If the request_data[:data][pluralized_parsed_root_element] fails, raise an exception that suggests manually specifying the root key.

If this seems acceptable, I can put in a PR.

[mikenichols]

I ran into this same problem and I struggled with it for a while. I was eventually able to get it working by explicitly specifying: parse_root_in_json true, format: :active_model_serializers. I like @smargh 's idea, it should try something sane.

[fractaledmind]

I may just put in a PR with this suggested fix.