Add "shop" Table to Django Admin

Hello When I try to migrate the data exported from overpass its giving me this error

File “C:\Users\13154\Anaconda3\lib\encodings\cp1252.py”, line 23, in decode return codecs.charmap_decode(input,self.errors,decoding_table)[0] UnicodeDecodeError: ‘charmap’ codec can’t decode byte 0x9d in position 26427: character maps to <undefined>

please help I am getting the same error on a windows machine ,a quick reply would be appreciated i need to submit this as a project

I am traveling with limited access. Do you mean to say your map data (location data in JSON) is causing the error?

@abairy and @snandw, you may have solved your problem already. If not or for anyone who runs into this issue in the future, I was able to resolve the issue by specifying the encoding upon opening the file. So it looks something like this.

...

with open(str(jsonfile), encoding = "utf8") as datafile:
        objects = json.load(datafile)
        for obj....

Hope this helps!

how to to use file.xlsx instead of file.json? and also how to add any type of file.

Just to add, the edit is done in your empty migration file for example mine is named 0002_auto_20200408_0157.py The edit is in this block;

with open(str**(jsonfile), encoding = "utf8") as **datafile:
    objects = json.load(datafile)
    for obj in objects['elements']:
        try:
            objType = obj['type']
            if objType == 'node':
                tags = obj['tags']
                name = tags.get('name','no-name')
                longitude = obj.get('lon', 0)
                latitude = obj.get('lat', 0)
                location = fromstr(f'POINT({longitude} {latitude})', srid=4326)
                Shop(name=name, location = location).save()
        except KeyError:
            pass

Thanks drewewhite1 for the pointer!

My Shops table is still empty…no error messages. This is my code:

# Generated by Django 3.0.5 on 2020-05-04 08:55

from django.db import migrations
import json
from django.contrib.gis.geos import fromstr
from pathlib import Path

DATA_FILENAME = 'export.json'

def load_data(apps, schema_editor):
    Shop = apps.get_model('nearbyshops', 'Shop')
    jsonfile = Path(__file__).parents[2] / DATA_FILENAME

    with open(str(jsonfile)) as datafile:
        objects = json.load(datafile)
        for obj in objects['elements']:
            try:
                objType = obj['type']
                if objType == 'node':
                    tags = obj['tags']
                    name = tags.get('name', 'no-name')
                    longitude = obj.get('lon', 0)
                    latitude = obj.get('lat', 0)
                    location = fromstr(
                        f'POINT({longitude} {latitude})', srid=4326
                    )
                    Shop(name=name, location=location).save()
            except KeyError:
                pass

class Migration(migrations.Migration):

    dependencies = [
        ('nearbyshops', '0001_initial'),
    ]

    operations = [
        migrations.RunPython(load_data)
    ]

I’ve been over my code a few times now. I’m now getting the following error message:

TypeError: Shop() got an unexpected keyword argument 'location'

My code is as follows:

# Generated by Django 3.0.5 on 2020-05-04 10:00

from django.db import migrations
import json
from django.contrib.gis.geos import fromstr
from pathlib import Path

DATA_FILENAME = 'export.json'

def load_data(apps, schema_editor):
    Shop = apps.get_model('nearbyshops', 'Shop')
    jsonfile = Path(__file__).parents[2] / DATA_FILENAME

    with open(str(jsonfile)) as datafile:
        objects = json.load(datafile)
        for obj in objects['elements']:
            try:
                objType = obj['type']
                if objType == 'node':
                    tags = obj['tags']
                    name = tags.get('name', 'no-name')
                    longitude = obj.get('lon', 0)
                    latitude = obj.get('lat', 0)
                    location = fromstr(
                        f'POINT({longitude} {latitude})', srid=4326
                    )
                    Shop(name=name, location=location).save()
            except KeyError:
                pass

class Migration(migrations.Migration):

    dependencies = [
        ('nearbyshops', '0001_initial'),
    ]

    operations = [
        migrations.RunPython(load_data)
    ]

As per the instructions in the video the export.json is on the same level as manage.py. I’ve been over this code a lot of times now, and I’ve tried googling, with no success…can anyone help out?

Hi, I’m running into an odd error that I believe is related the map data but I’ve follow the instructions in the video for querying shops in Baltimore and downloading as raw OSM data.

django.contrib.gis.geos.error.GEOSException: Error encountered checking Geometry returned from GEOS C function "GEOSWKTReader_read_r".

My migration code is below, but otherwise I’m unsure of what may be the issue. I’ve retraced it, and redownloaded the export.json data to no avail.

My code is below: ``` # Generated by Django 3.0.8 on 2020-07-21 05:08

from django.db import migrations import json from django.contrib.gis.geos import fromstr from pathlib import Path

DATA_FILENAME = ‘export.json’

def load_data(apps, schema_editor): Shop = apps.get_model(‘nearbyshops’, ‘Shop’) jsonfile = Path(file).parents[2] / DATA_FILENAME

with open(str(jsonfile)) as datafile:
    objects = json.load(datafile)

    for obj in objects['elements']:
        try:
            objType = obj['type']
            if objType == 'node':
                tags = obj['tags']
                name = tags.get('name', 'no-name')
                longitude = obj.get('lon', 0)
                latitude = obj.get('lat', 0)
                location = fromstr(f'POINT({longitude} {latitude}', srid=4326)

                Shop(name=name, location=location).save()
        except KeyError:
            pass

class Migration(migrations.Migration):

dependencies = [
    ('nearbyshops', '0001_initial'),
]

operations = [
    migrations.RunPython(load_data)
]

```

FYI - After spending some ‘extended happy time’ googling and checking my installs and code, I discovered that attempting to view the location in /Admin using OSMGeoAdmin doesn’t display the map correctly if using Safari, but works using Chrome. Hope this helps others!

See FAQ here for the source of my new found wisdom.

Enjoying the style and pace of the Tutorial all the same!

from django.db import migrations
import json
from django.contrib.gis.geos import fromstr
from pathlib import Path

DATA_FILENAME = 'export.json'

def load_data(apps, schema_editor):
    Shop = apps.get_model('nearbyshops', 'Shop')
    jsonfile = Path(__file__).parents[2] / DATA_FILENAME

    with open(str(jsonfile)) as datafile:
        objects = json.load(datafile)
        for obj in objects['elements']:
            try:
                objType = obj['type']
                if objType == 'node':
                    tags = obj['tags']
                    name = tags.get('name', 'no-name')
                    longitude = obj.get('lon', 0)
                    latitude = obj.get('lat', 0)
                    location = fromstr(
                        f'POINT({longitude} {latitude})', srid=4326
                    )
                    Shop(name=name, location=location).save()
            except KeyError:
                pass

class Migration(migrations.Migration):

    dependencies = [
        ('nearbyshops', '0001_initial'),
    ]

    operations = [
        migrations.RunPython(load_data)
    ]

Please help me out here. My shops are not loading on my django site. Don’t know what happening.

Not sure this was anyone’s issue, but be sure your syntax is correct. I found an error in my f-string, which was:

location = fromstr(
    f'POINT({longitude}, {latitude}', srid=4326

I was shocked this didn’t pick up. Explanation why I was getting a GEOSException versus a syntax error?

The correct syntax is:

location = fromstr(
    f'POINT({longitude} {latitude})', srid=4326
)

One little closing parenthesis :)

Oh the joys (and pains of missing parentheses! (we’ve (probably all been there…

) 😜

Thanks for the heads-up to check your syntax @ Joe Madaus! And to reduce the amount of times you run into annoying stuff like that, you can use a Python IDE or code editor that helps you by highlighting issues with your syntax right when you’re writing your code.

Hi Martin

I do use PyCharm which is why I was perplexed. It was late though so it’s possible PyCharm was teling me but I didn’t see it. Really good tutorial. We should expand this to be more user interactive.

Ah yes I also miss things like this every so often, despite all the IDE support! I’ll more quickly spot the mistake after it’s gone wrong though with the text editor highlighting :)

What do you mean about expanding it to be more user-interactive @Joe Madaus?

Hello again Martin. First, thanks for listening to feedback.

What I mean is a web form with users entering points on a map, those points autofilling a field. Then give the user the ability to input information about them. Kind of like a blog or something. Like a “places I’ve been” sort of thing with user “memories” they can share or not. Then rank those against “other user places” should the user choose to do so. Something like that.

That’s a great addition to this project @Joe Madaus! 🙌 🗺

For implementing this, you’ll need a way for your users to submit content to your Django back end. Here are a couple of links that might help you piece that functionality together:

• Working with Forms
• Build a Personal Diary With Django and Python
• Django User Management

You’ll have to pick out the relevant content, but if you go through this process and keep working on it, you’ll definitely learn a lot about Django and you’ll have a cool project to show at the end! :D Let me know if you work it out, I’ll come and record some places there!

Martin

Sounds awesome and thanks for the tips!!! I will definitely let you know when i finish it.

Hello there, When I run makemigrations it says ‘No changes detected’, any ideas? export.json is in the same place as shown in video. I’m on a Mac M1 running Ventura 13.5

thanks, Kim

Nevermind, figured it out, just a stupid mistake....

I try everything to solve the problem with django.contrib.gis.admin import OSMGeoAdmin but doesn’t work at all!! I have follow all the steps and instructions on gdal.org/download.html but nothing solves too.

We need a update from that lesson on Real Python.

My error is: when run python manage.py runserver

ImportError: cannot import name ‘OSMGeoAdmin’ from ‘django.contrib.gis.admin’.

@Rafael Tenorio Gama I got stuck on the same part but got it to work using the following in my admin.py file. However, i haven’t figured out how to make the list_display option work yet.

from django.contrib import admin
from django.contrib.gis.admin import GISModelAdmin
from .models import Shop

admin.site.register(Shop, GISModelAdmin)

I found this at the very bottom of the following django doc. GeoDjango Tutorial Hope this helps.

@gabriel and @Rafael Tenorio Gama I was able to get it working with the following in admin.py

from django.contrib.gis import admin
from django.contrib.gis.admin import GISModelAdmin
from .models import Shop

@admin.register(Shop)
class ShopAdmin(GISModelAdmin):
    list_display = ('name', 'location')

Also, I found GISModelAdmin by discovering this: django.readthedocs.io/en/4.2.x/ref/contrib/gis/admin.html#osmgeoadmin

Just want to say thanks to gabriel and jwil above me: I had the same problem as them and using GISModelAdmin instead of OSMGeoAdmin solved the issue. It is a shame RealPython does not want to update the Contents tab with these solutions.