OrderedDict working locally, but not in Messenger chatbot using Heroku and Flask

Question

I have an OrderedDict like this:

od = OrderedDict({
                'a':{'1-k1':'v1',
                     '2-k2':'v2',
                     '3-k3':'v3',
                     },
                'b':{'4-k4':'v4'},
                    {'5-k5':'v5'},
                    {'6-k6':'v6'},
                })

And I wanted to get a list of all keys in one of the second-level dictionaries, so I did:

aod = OrderedDict(od.get('a'))
a_message = ''
for a_key in list(aod.keys()):
    a_message = amessage + a_key + ' \n'  
print (a_message)

Now here's the thing, when I run this in a local script, it outputs:

"
1-k1
2-k2
3-k3
"

But, when I integrated it in my Messenger Chatbot using Heroku, the list isn't in order. I thought there might be something interfering in the app script, so I put that block of code at the top and printed it right after it finished, and it was still unordered. I also tried making the inner dictionaries Ordered too.

So what would cause an OrderedDict list, that's working locally, to be unordered after deployment?

Moses Koledoye · Accepted Answer · 2017-05-04T15:44:36.330

1

The ordering in your local machine is mere happenstance. The nested dicts are vanilla dicts, and the idea of ordering is not applicable.

You need to make the nested dicts instances of OrderedDict to get the ordering you want:

od = OrderedDict([
                ('a': OrderedDict(...)),
                ...
                ])

You should change the data structure, and not call OrderedDict on a dictionary, as that does not guarantee the order you want

edited May 04 '17 at 15:44

answered May 04 '17 at 15:12

Moses Koledoye

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I tried this too and it still won't work, I also ran it many times, so it's probably not a coincidence. – Mohamed Mohey May 04 '17 at 15:19
The output from the Heroku app is an OrderedDict, but its contents aren't ordered like the local script. – Mohamed Mohey May 04 '17 at 15:24
@MohamedMohey You should change the data structure, and not call `OrderedDict` on a dictionary, as that does not guarantee the order you want. – Moses Koledoye May 04 '17 at 15:38

score -1 · Answer 2 · answered May 04 '17 at 15:41

I actually solved this by converting the dictionary to a list of tuples. Looks like the dictionary didn't store the order even though I called OrderedDict. My dict now looks like this:

`od = OrderedDict([('a',OrderedDict([
                     ('1-k1','v1'),
                     ('2-k2','v2'),
                     ('3-k3','v3'),
                     ]))

 ])`

OrderedDict working locally, but not in Messenger chatbot using Heroku and Flask

2 Answers2