使用 psycopg 将 json 中的嵌套字段从 REST API 解析到 PostgreSQL

Question

我正在使用 python 开发一个项目，在该项目中我使用请求从 REST API 获取 json，然后继续将其加载到 PostgreSQL 数据库中。 API 响应的 json 结构如下所示。我的主要问题是关于嵌套字段，如location.lat 和嵌套在info 数组中的字段，如info[0].value。

{

"items": [
    {
        "id": 300436,
        "item_id_parent": null,
        "reference": "",
        "subreference1": "CAMS\/1",
        "subreference2": "CAMS\/1",
        "reference_alpha": null,
        "reference_numeric": null,
        "oid": "CAMS\/1",
        "code": null,
        "code_custom": null,
        "name": "284",
        "image": "https:\/\/static.inventsys.com.br\/278\/thumb\/f-3298886-200x200c.jpg",
        "situations": [],
        "project_id": 10762,
        "project": {
            "id": 10762,
            "name": "Fauna EGR",
            "color": null
        },
        "category_id": 20685,
        "category": {
            "id": 20685,
            "name": "EGR FAUNA - Armadilhas"
        },
        "area_id": null,
        "area": null,
        "location": {
            "lat": -30.136699676514,
            "lng": -50.910511016846,
            "address": {
                "region": "RS",
                "city": "Viamão",
                "district": null,
                "zipcode": null,
                "street": "Rodovia Tapir Rocha",
                "street_number": null,
                "desc": null,
                "full": "Rodovia Tapir Rocha Viamão \/ BR"
            }
        },
        "event_last": null,
        "description": null,
        "search_terms": "CAMS\/1 284 Fauna EGR EGR FAUNA - Armadilhas Rodovia Tapir Rocha Viamão \/ BR",
        "info": [
            {
                "id": 42725,
                "name": "Observacoes",
                "type": "longtext",
                "value": null,
                "fvalue": null,
                "description": null,
                "ikey": null,
                "group": "Fauna EGR",
                "preload": false,
                "filling": false,
                "primary": false,
                "created": null
            },
            {
                "id": 44542,
                "name": "Data de instalacao",
                "type": "date",
                "value": null,
                "fvalue": null,
                "description": null,
                "ikey": null,
                "group": "Fauna EGR",
                "preload": false,
                "filling": false,
                "primary": false,
                "created": null
            },...

到目前为止，我知道我需要命名字段并为表中的每个变量建立一个占位符，这就是我迄今为止所拥有的：

import psycopg2

conn = psycopg2.connect("host=localhost dbname=postgres user=guilhermeiablonovski") cur = conn.cursor()

dbarmadilhas = """DROP TABLE IF EXISTS egrfauna_armadilhas; CREATE UNLOGGED TABLE IF NOT EXISTS egrfauna_armadilhas( id text PRIMARY KEY, name text, image text, category_id integer, category_name text, latitude real, longitude real, imagem_orig text, observacoes text, instalacao DATE, IDcartao text, IDcamera text, IDbueiro text, estrada text, foto_armadilha text, gps_lat real, gps_long real, gps_alt real, gps_acc real);"""

cur.execute(dbarmadilhas) conn.commit()

armadilha_fields = [
    'id',
    'name',
    'image',
    'category_id',
    'category.name',
    'location.lat',
    'location.lng',
    'files[0].url_orig',
    'files[1].url_low',
    'info[0].value',
    'info[1].value',
    'info[2].value',
    'info[3].value',
    'info[4].value',
    'info[5].value',
    'info[6].value',
    'info[7].value',
    'info[8].value',
    'info[9].value',
    'info[10].value',
    'info[11].value' ]

for item in registros:
    my_data = [item[field] for field in armadilha_fields]
    # need a placeholder (%s) for each variable 
    # refer to postgres docs on INSERT statement on how to specify order
    cur.execute("INSERT INTO egrfauna_armadilhas VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s)", tuple(my_data))

conn.commit()

这里的问题是，如果我只使用前四个变量运行代码，它可以正常工作，所以我想我的语法在我想要解析的嵌套字段时都是错误的。我怎样才能最好地参考这些领域？

提前谢谢大家！

Answer 1

为了以后参考，这样解决了：

for item in registros:
    armadilhafields = [
    item['id'],
    item['name'],
    item['image'],
    item['category_id'],
    item['category']['name'],
    item['location']['lat'],
    item['location']['lng'],
    item['files'][0]['url_orig'],
    item['info'][0]['value'],
    item['info'][1]['value'],
    item['info'][2]['value'],
    item['info'][3]['value'],
    item['info'][4]['value'],
    item['info'][5]['value'],
    item['info'][6]['value'],
    item['info'][7]['value'],
    item['info'][8]['value'],
    item['info'][9]['value'],
    item['info'][10]['value'],
    ]
    my_data = [field for field in armadilhafields]
    cur.execute("INSERT INTO egrfauna_armadilhas VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s)", tuple(my_data))



conn.commit()