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高德實(shí)時(shí)路況數(shù)據(jù)獲取接口說(shuō)明：
link - 高德數(shù)據(jù)獲取流程
- 數(shù)據(jù)庫(kù)設(shè)計(jì)
CREATE TABLE "public"."gaode_date" (
"name" varchar(50) COLLATE "default",
"status" int4,
"direction" varchar(50) COLLATE "default",
"angle" int4,
"lcodes" varchar(255) COLLATE "default",
"polyline" text COLLATE "default",
"id" int4 DEFAULT nextval('gaode_id_seq'::regclass) NOT NULL,
"geom" "public"."geometry",
"date" date,
"time" time(6),
"speed" float8,
CONSTRAINT "gaode_date_pkey" PRIMARY KEY ("id")
)
WITH (OIDS=FALSE)
;
ALTER TABLE "public"."gaode_date" OWNER TO "postgres";
COMMENT ON COLUMN "public"."gaode_date"."name" IS '道路名稱';
COMMENT ON COLUMN "public"."gaode_date"."status" IS '路況 0：未知 1：暢通 2：緩行 3：擁堵';
COMMENT ON COLUMN "public"."gaode_date"."direction" IS '方向描述';
COMMENT ON COLUMN "public"."gaode_date"."angle" IS '車行角度，判斷道路正反向使用。以正東方向?yàn)?度，逆時(shí)針?lè)较驗(yàn)檎?，取值范圍：[0,360]';
COMMENT ON COLUMN "public"."gaode_date"."lcodes" IS '方向';
COMMENT ON COLUMN "public"."gaode_date"."polyline" IS '道路坐標(biāo)集，坐標(biāo)集合';
COMMENT ON COLUMN "public"."gaode_date"."date" IS '請(qǐng)求日期';
COMMENT ON COLUMN "public"."gaode_date"."time" IS '請(qǐng)求時(shí)間';
COMMENT ON COLUMN "public"."gaode_date"."speed" IS '速度';
CREATE TRIGGER "beforeinsertinsertgaodedata_trigger" BEFORE INSERT ON "public"."gaode_date"
FOR EACH ROW
EXECUTE PROCEDURE "beforeinsertgaodedata"();
- 請(qǐng)求高德數(shù)據(jù)Python腳本
import requests
import json
import time
from pandas import DataFrame
import psycopg2
#請(qǐng)求高德實(shí)時(shí)路況數(shù)據(jù)
def getGaodeTrafficStatus(key,rectangle,currentTime):
insert_list = []
TrafficStatusUrl = 'http://restapi.amap.com/v3/traffic/status/rectangle?key='+key+'&rectangle='+rectangle+'&extensions=all';
res = requests.get(url=TrafficStatusUrl).content;
total_json = json.loads(res);
print(total_json);
jsondata = total_json['trafficinfo']['roads'];
print(jsondata);
currentDate = time.strftime("%Y-%m-%d", time.localtime());
if any(jsondata):
for i in jsondata:
name = i['name']
status = i['status']
direction = i['direction']
angle = i['angle']
speed = i.get('speed');
# 若速度參數(shù)缺失，補(bǔ)為Null
if speed == None:
speed = None;
print(speed);
lcodes = i['lcodes']
polyline = i['polyline']
list = [name, status, direction, angle, lcodes, polyline, currentDate, currentTime, speed];
insert_list.append(list);
conn = psycopg2.connect(database="superpower", user="postgres", password="123456", host="localhost", port="5432");
cur = conn.cursor();
for i in insert_list:
if len(i):
cur.execute(
"insert into gaode_date(name, status, direction, angle, lcodes, polyline, date, time,speed) values (%s,%s,%s,%s,%s,%s,%s,%s,%s)",
i)
conn.commit()
conn.close()
else:
pass
#注冊(cè)多個(gè)高德key,輪流使用，并記錄請(qǐng)求的個(gè)數(shù)，滿2000次換下一個(gè)key繼續(xù)請(qǐng)求。
keyList=[{}];
#建立覆蓋研究區(qū)的rectangle數(shù)組
rectangleList=[];
#創(chuàng)建請(qǐng)求時(shí)間，確保一次請(qǐng)求的時(shí)間都相同
currentTime = time.strftime("%H:%M:%S", time.localtime()); # 設(shè)置請(qǐng)求時(shí)間
key='yourKey';
rectangle='120.12924,30.30185;120.16018,30.27150';
getGaodeTrafficStatus(key,rectangle，currentTime);
- 空間信息解析（在此采用觸發(fā)器，對(duì)數(shù)據(jù)進(jìn)行解析，插入數(shù)據(jù)的同時(shí)完成空間信息的解析，減少人工參與。），觸發(fā)器Sql腳本如下：
--高德數(shù)據(jù)插入觸發(fā)器
CREATE OR REPLACE FUNCTION BeforeInsertGaodeData() RETURNS TRIGGER AS $example_table$
BEGIN
--自動(dòng)進(jìn)行坐標(biāo)計(jì)算，并賦值
NEW.geom=ST_LineFromText('LINESTRING('||replace(replace(New.polyline,',',' '),';',',')||')',4326);
return new;
End ;
$example_table$ LANGUAGE plpgsql;
CREATE TRIGGER BeforeInsertInsertGaodeData_trigger Before INSERT ON gaode_date FOR EACH ROW EXECUTE PROCEDURE BeforeInsertGaodeData ();
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數(shù)據(jù)查看，可視化獲取的高德數(shù)據(jù)，如下（未正兒八經(jīng)的進(jìn)行渲染：）
image 爬取整個(gè)研究區(qū)域的實(shí)時(shí)路況數(shù)據(jù)
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構(gòu)建整個(gè)研究區(qū)域的網(wǎng)格，如下圖，構(gòu)建網(wǎng)格過(guò)程略。
image 網(wǎng)格數(shù)據(jù)庫(kù)腳本
CREATE TABLE "public"."hangzhou_grid" (
"gid" int4 DEFAULT nextval('hangzhou_grid_gid_seq'::regclass) NOT NULL,
"id" numeric(10),
"__xmin" numeric,
"__xmax" numeric,
"ymin" numeric,
"ymax" numeric,
"geom" "public"."geometry",
CONSTRAINT "hangzhou_grid_pkey" PRIMARY KEY ("gid")
)
WITH (OIDS=FALSE)
;
ALTER TABLE "public"."hangzhou_grid" OWNER TO "postgres";
COMMENT ON COLUMN "public"."hangzhou_grid"."__xmin" IS '最小x';
COMMENT ON COLUMN "public"."hangzhou_grid"."__xmax" IS '最大x';
COMMENT ON COLUMN "public"."hangzhou_grid"."ymin" IS '最小y';
COMMENT ON COLUMN "public"."hangzhou_grid"."ymax" IS '最大y';
CREATE INDEX "hangzhou_grid_geom_idx" ON "public"."hangzhou_grid" USING gist ("geom");
3.請(qǐng)求整個(gè)杭州高德實(shí)時(shí)路況數(shù)據(jù)Python腳本
#請(qǐng)求整個(gè)杭州的區(qū)域
conn = psycopg2.connect(database="superpower", user="postgres", password="123456", host="localhost", port="5432");
cur = conn.cursor();
#獲取覆蓋研究區(qū)域的網(wǎng)格
cur.execute("select t.__xmin||','||t.ymin||';'||t.__xmax||','||t.ymax rectangle from hangzhou_grid t");
rectangleData=cur.fetchall();
cur.close;
conn.close();
#創(chuàng)建請(qǐng)求時(shí)間，確保一次請(qǐng)求的時(shí)間都相同
currentTime = time.strftime("%H:%M:%S", time.localtime()); # 設(shè)置請(qǐng)求時(shí)間
for rec in rectangleData:
print(rec[0]);
getGaodeTrafficStatus(key,rec[0],currentTime);
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查看請(qǐng)求結(jié)果，如下圖
image
- 總結(jié)
- 該方法基本能夠?qū)⒄?qǐng)求區(qū)域里的數(shù)據(jù)，進(jìn)行覆蓋。
- 獲取的數(shù)據(jù)只是原始數(shù)據(jù)，若需要進(jìn)行使用可能需要進(jìn)行進(jìn)一步處理，如將某時(shí)刻重復(fù)數(shù)據(jù)去除等。
- 高德API接口有請(qǐng)求次數(shù)的限制，因此要覆蓋大多數(shù)時(shí)間，需要申請(qǐng)多個(gè)key,大致是60個(gè)key,目前不知道高德有沒(méi)有限制一個(gè)IP地址訪問(wèn)次數(shù)。（后面持續(xù)改進(jìn)方向：建立key表記錄每個(gè)key一天訪問(wèn)的次數(shù)，動(dòng)態(tài)分配key）
- 該方法也可以構(gòu)建研究區(qū)域的主要道路，解放道路采集的人力。
