[英]Python/Flask Server Side - Java/HttpURLConnection Client - REST Implementation
我目前正在從支持該服務的桌面應用程序實現我的Web應用程序的REST接口。 我們使用Python和Flask進行REST服務器實現。
我們有一種情況,Java客戶端將請求POST,python服務器端將處理該帖子,直到它需要連接到MySQL數據庫。
這是python / flask代碼:
@app.route("/update_project/<project_data>", methods=['GET','POST'])
def updateWPProject(project_data):
"""project_data = user+++++pw+++++pj_jsondoc.
This will update an existing project data or insert a non-existant project data item."""
usrpw = project_data.split("+++++")
dblogin = wplogin(usr=usrpw[0], pw=usrpw[1])
if dblogin[0] == 'SUCCESS':
db_name = dblogin[1][0].strip()
db_user = dblogin[1][1].strip()
db_pw = dblogin[1][2].strip()
if flask.request.method == 'POST':
fname = flask.request.form['fName']
if fname:
pj = Project()
try:
pj = json.loads(fname)
except TypeError:
sys.stdout.write("JSON conversion error...%s" % sys.exc_info()[0])
except AttributeError:
sys.stdout.write("JSON conversion error...%s" % sys.exc_info()[0])
updateProject(db_name,db_user,db_pw,pj)
#return redirect(url_for('/'))
else:
return 'Login failure.'
pass
這可以正常工作,直到它到達'updateProject(db_name,db_user,db_pw,pj)'行。 然后它將轉到該函數,並在'cursor = conn.cursor()'處返回500而不完成該函數。
def updateProject(dbname, dbuser, dbpw, pj):
"""Updates or inserts a project record is not exists. PJ passed as an argument is a Project object."""
try:
conn = getConnection(dbuser, dbpw, dbname)
cursor = conn.cursor()
except:
sys.stdout.write("MySQL connection error...%s" % sys.exc_info()[0])
sql_stmt = """INSERT INTO projects( projNo, projName, worksteplabel, workstep1label, workstep2label, workstep3label, resultlabel, result1label, result2label, result3label, projectowner, dbname, dblogin, dbpw, role, preference1, preference2, preference3 )
VALUES (
'projNo', 'projName', 'wslabel', 'wslabel', 'wslabel', 'wslabel', 'rlabel', 'rlabel', 'rlabel', 'rlabel', 'pjowner', 'dbname', 'dblogin', 'dbpw', 'role', 'pref1', 'pref2', 'pref3'
) ON DUPLICATE
KEY UPDATE projName = 'projName',
worksteplabel = 'wslabel',
workstep1label = 'wslabel',
workstep2label = 'wslabel',
workstep3label = 'wslabel',
resultlabel = 'rlabel',
result1label = 'rlabel',
result2label = 'rlabel',
result3label = 'rlabel',
projectowner = 'pjowner',
dbname = 'dbname',
dblogin = 'dblogin',
dbpw = 'dbpw',
role = 'role',
preference1 = 'pref1',
preference2 = 'pref2',
preference3 = 'pref3' )
try:
cursor.execute(sql_stmt)
return 'SUCCESS'
except MySQLdb.Error:
sys.stdout.write("MySQLdb error...%s" % sys.exc_info()[0])
return 'FAILURE'
在Java客戶端,我使用以下代碼從客戶端發送POST請求和數據。
public void DB_NewProjectREST(ProjectData proj, WPUser usr) {
// public static String excutePost(String targetURL, String urlParameters)
//URL url;
HttpURLConnection connection = null;
///First, all the GSON/JSon stuff up front
Gson gson = new Gson();
//convert java object to JSON format
String json = gson.toJson(proj);
//Then credentials and send string
String send_string = usr.getUserEmail()+"+++++"+usr.getUserHash();
try {
//Create connection
URL url = new URL("http://127.0.0.1:5000/update_project/"+send_string);
String urlParameters = "fName=" + URLEncoder.encode(json, "UTF-8");
connection = (HttpURLConnection)url.openConnection();
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
connection.setRequestProperty("Content-Length", "" + Integer.toString(urlParameters.getBytes().length));
connection.setRequestProperty("Content-Language", "en-US");
connection.setUseCaches(false);
connection.setDoInput(true);
connection.setDoOutput(true);
//Send request
DataOutputStream wr = new DataOutputStream (connection.getOutputStream ());
wr.writeBytes (urlParameters);
wr.flush ();
wr.close ();
//Get Response
InputStream is = connection.getInputStream();
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
String line;
StringBuffer response = new StringBuffer();
while((line = rd.readLine()) != null) {
response.append(line);
response.append('\r');
}
rd.close();
} catch (Exception e) {
e.printStackTrace();
//return null;
}finally {
if(connection != null) {
connection.disconnect();
}
}
}
看起來我必須將某種響應(對於輸入流)發送回客戶端,這就是我的python代碼突然返回的地方。(?)數據從java客戶端到python / flask代碼,那么有沒有辦法快速返回'OK'並繼續處理db更新。 或者,python updateProject函數中的游標連接調用是否以某種方式干擾了http連接?
任何幫助贊賞。
這是python服務器端的代碼,但不確定它是否是'正確'的方式....
@app.route("/update_project/<project_data>", methods=['GET','POST'])
def updateWPProject(project_data):
"""project_data = user+++++pw+++++pj_jsondoc.
This will update an existing project data or insert a non-existant project data item."""
usrpw = project_data.split("+++++")
dblogin = wplogin(usr=usrpw[0], pw=usrpw[1])
if dblogin[0] == 'SUCCESS':
db_name = dblogin[1][0].strip()
db_user = dblogin[1][1].strip()
db_pw = dblogin[1][2].strip()
if flask.request.method == 'POST':
fname = flask.request.form['fName']
if fname:
pj = Project()
try:
pj = json.loads(fname)
try:
#threading.Thread(target=updateProject, args=(db_name,db_user,db_pw,pj)).start()
return Response(updateProject(db_name,db_user,db_pw,pj), direct_passthrough=True)
except Exception, errtxt:
sys.stdout.write(errtxt)
#threading.thread.start_new_thread(updateProject,(db_name,db_user,db_pw,pj))
except TypeError:
sys.stdout.write("JSON conversion error...%s" % sys.exc_info()[0])
except AttributeError:
sys.stdout.write("JSON conversion error...%s" % sys.exc_info()[0])
else:
return 'Login failure.'
pass
最值得注意的是,'返回響應(......'是解決了這個挑戰。我想。
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.