Couchbase View _count Reduce For Given Keys - mapreduce

Question

I am trying to write a view in Couchbase using a reduce such as _count which will give me a count of the products at an address.
I have some documents in the database in the following format;
Document 1
{
id: 1,
address: {
street: 'W Churchill St'
city: 'Chicago',
state: 'IL',
},
product: 'Cable'
}
Document 2
{
id: 2,
address: {
street: 'W Churchill St'
city: 'Chicago',
state: 'IL',
},
product: 'Cable'
}
Document 3
{
id: 3,
address: {
street: 'W Churchill St'
city: 'Chicago',
state: 'IL',
},
product: 'Satellite'
}
Document 4
{
id: 4,
address: {
street: 'E Foster Rd'
city: 'New York',
state: 'NY',
},
product: 'Free To Air'
}
I already have a view which gives me all the products at an address which uses a composite key such as;
emit([doc.address.street, doc.address.city, doc.address.state], null)
Now this leads me on to the actual problem, I want to be able to get a count of products at a address or addresses.
I want to be able to see for an array of "keys"
['W Churchill St','Chicago','IL']
['E Foster Rd','New York','NY']
which products and a count of them. So i would expect to see in my results.
'Cable' : 2,
'Satellite': 1,
'Free To Air': 1
however if I specified only this "key",
['W Churchill St','Chicago','IL']
I would expect to see
'Cable' : 2,
'Satellite': 1
How to write my view to accommodate this?

Answer 1

The solution to this was to append my product to the key like so;
emit([doc.address.street, doc.address.city, doc.address.state, doc.product], null)
Then using;
?start_key=[street,city,state]&end_key=[street,city,state,{}]&group_level=4
Result:
{"rows":[
{"key":['W Churchill St','Chicago','IL','Cable'], "value":2},
{"key":['W Churchill St','Chicago','IL','Satellite'], "value":1}
]}
I would then need to repeat this query for each of the addresses and sum the results.