Addok search2steps

Addok plugin to support search an address in two steps.

This plugin run a first query on a sub part of the data and then use the knowledge of this result as context of a second query.

Typically, help ensure results are in a city when you already know witch parts of the address are street, city or postal code.

Addressed problem

For query:

street="Rue Beau Soleil", city="Sains"

Vanilla Addok query, found a street but in wrong city:

Rue Beau Soleil 44310 Saint-Philbert-de-Grand-Lieu

Two steps query, found an approximate street name in right city:

Rue Beau Site 35610 Sains

Usage

Use as normal Addok search query, with required q and other limit, autocomplete, etc, including filters.

Search2steps introduce a new parameter: q0 for preliminary search.

http://localhost:7878/search2steps?q0=Brest&q=Rue+du+Restic&limit=5

Configuration

Install the python module, no explicit load is necessary.

The default configuration is:

SEARCH_2_STEPS_STEP1_TYPES = ['municipality']
SEARCH_2_STEPS_STEP1_THRESHOLD = 0.2
SEARCH_2_STEPS_STEP1_LIMIT = 10

SEARCH_2_STEPS_PIVOT_FILTER = 'citycode'
SEARCH_2_STEPS_PIVOT_REWRITE = 'name'

SEARCH_2_STEPS_STEP2_TYPE = 'housenumber'
SEARCH_2_STEPS_STEP2_THRESHOLD = 0.2
SEARCH_2_STEPS_STEP2_PENALITY_MULTIPLIER = 0.5

You can overive it in your configuration file.

How it works

Search in addok in two steps by:

• Search by q0 and extract the selected pivot
• Search by q0 + q using the pivot as filter

Step one

Configuration must specify the type of object looked for in this step, it's used as filter in step one.

SEARCH_2_STEPS_STEP1_TYPES = ['municipality', 'locality']

Only result with score above the threshold and under this limit will remain available for next step:

SEARCH_2_STEPS_STEP1_THRESHOLD = 0.5
SEARCH_2_STEPS_STEP2_TYPE = 'housenumber'
SEARCH_2_STEPS_STEP1_LIMIT = 10

Pivot

Then specify which field would be extract from step one and use as filter on step two:

SEARCH_2_STEPS_PIVOT_FILTER = 'citycode'

q0 will be replaced by this 'normalized' value of result of step one in query of step two:

SEARCH_2_STEPS_PIVOT_REWRITE = 'municipality'

Step two

Only result with score above the threshold will remain in the returned result:

SEARCH_2_STEPS_STEP2_THRESHOLD = 0.2

Fail safe

If two steps query fail, a classic q0 + q query is done. All result scores are lowered by SEARCH_2_STEPS_STEP2_PENALITY_MULTIPLIER.

Example

Initial query:

q0=Bordeaux
q=Rue des lilas
limit=1

Step one:

query:
    q=Bordeaux type=city limit=10
return:
    citycode=33063, name=Bordeaux
    citycode=76117, name=Bordeaux-Saint-Clair
    citycode=33245, name=Lignan-de-Bordeaux

Step two:

query:
    q="Bordeaux Rue des lilas" citycode=33063 limit 1
    q="Bordeaux-Saint-Clair Rue des lilas" citycode=76117 limit 1
    q="Lignan-de-Bordeaux Rue des lilas" citycode=33245 limit 1

Bonus

The street can be a list of possible candidates when come from a loseley casted address.

street? App 6
street? Rue Beau Rosier
postcode: 33000
city: Bordeaux

Separate possible alternate street names with a pipe |:

q0=33000+Bordeaux&q=App+6|Rue+Beau+Rosier