bash中的反向地理编码

Question

I have a gps unit which extracts longitude and latitude and outputs as a google maps link

http://maps.googleapis.com/maps/api/geocode/xml?latlng=51.601154,-0.404765&sensor=false

From this i'd like to call it via curl and display the "short name" in line 20

"short_name" : "Northwood",

so i'd just like to be left with

Northwood

so something like

curl -s http://maps.googleapis.com/maps/api/geocode/xml?latlng=latlng=51.601154,-0.404765&sensor=false sed sort_name

Answer 1

Mmmm, this is kind of quick and dirty:

curl -s "http://maps.googleapis.com/maps/api/geocode/json?latlng=40.714224,-73.961452&sensor=false" | grep -B 1 "route" | awk -F'"' '/short_name/ {print $4}'
Bedford Avenue

It looks for the line before the line with "route" in it, then the word "short_name" and then prints the 4th field as detected by using " as the field separator. Really you should use a JSON parser though!

Notes:

1. This doesn't require you to install anything.
2. I look for the word "route" in the JSON because you seem to want the road name - you could equally look for anything else you choose.
3. This isn't a very robust solution as Google may not always give you a route, but I guess other programs/solutions won't work then either!
4. You can play with my solution by successively removing parts from the right hand end of the pipeline to see what each phase produces.

EDITED

Mmm, you have changed from JSON to XML, I see... well, this parses out what you want, but I note you are now looking for a locality whereas before you were looking for a route or road name? Which do you want?

curl -s "http://maps.googleapis.com/maps/api/geocode/xml?latlng=51.601154,-0.404765&sensor=false" | grep -B1 locality | grep short_name| head -1|sed -e 's/<\/.*//' -e 's/.*>//'

The "grep -B1" looks for the line before the line containing "locality". The "grep short_name" then gets the locality's short name. The "head -1" discards all but the first locality if there are more than one. The "sed" stuff removes the <> XML delimiters.

Answer 2

This isn't text, it's structured JSON. You don't want the value after the colon on line 12, you want the value of short name in the address_component with type 'route' from the result.

You could do this with jsawk or python , but it's easier to get it from XML output with xmlstarlet , which is lighter than python and more available than jsawk. Install xmlstarlet and try:

curl -s 'http://maps.googleapis.com/maps/api/geocode/xml?latlng=40.714224,-73.961452&sensor=false' \
| xmlstarlet sel -t -v '/GeocodeResponse/result/address_component[type="route"]/short_name'

This is much more robust than trying to parse JSON as plaintext.

Answer 3

The following seems to work assuming you always like the short_name at line 12:

curl -s 'http://maps.googleapis.com/maps/api/geocode/json?latlng=40.714224,-73.961452&sensor=false' | sed -n -e '12s/^.*: "\([a-zA-Z ]*\)",/\1/p'

or if you are using the xml api and wan't to trap the short_name on line 20:

curl -s 'http://maps.googleapis.com/maps/api/geocode/xml?latlng=51.601154,-0.404765&sensor=false' | sed -n -e '19s/<short_name>\([a-zA-Z ]*\)<\/short_name>/\1/p'