The Ring programming language version 1.5.1 book - Part 42 of 180

1. Ring Documentation, Release 1.5.1
47.21 CRUD Example using MVC
The next example uses the weblib.ring & datalib.ring.
The datalib.ring contains classes for creating database applications using MVC pattern.
In this example we create an object from the SalaryController class then call the Routing method.
We define the website variable to contains the basic url of the page.
When we create the SalaryModel class from the ModelBase class, the salary table will be opened and the columns
data will be defined as attributes in the model class.
The SalaryView class create an object from the SalaryLanguageEnglish class to be used for translation.
The method AddFuncScript is used to call the form for adding/modifying record data.
The method FormViewContent is used to determine the controls in the form when we add or modify a record.
#!c:ringbinring.exe -cgi
Load "weblib.ring"
Load "datalib.ring"
Import System.Web
website = "ex24.ring"
New SalaryController { Routing() }
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2. Ring Documentation, Release 1.5.1
Class SalaryModel from ModelBase
Class SalaryController From ControllerBase
Class SalaryView From ViewBase
oLanguage = new SalaryLanguageEnglish
Func AddFuncScript oPage,oController
return oPage.scriptfuncajax("myadd",oController.cMainURL+
oController.cOperation+"=add","mysubpage")
Func FormViewContent oController,oTranslation,oPage
return [
[ oTranslation.aColumnsTitles[2], "textbox", "name",
oController.oModel.Name, oPage.stylewidth("100%") ],
[ oTranslation.aColumnsTitles[3], "textbox", "salary",
oController.oModel.Salary, oPage.stylewidth("50%") ]
]
Class SalaryLanguageEnglish
cTitle = "Salary Table"
cBack = "back"
aColumnsTitles = ["ID","Name","Salary"]
cOptions = "Options"
cSearch = "Search"
comboitems = ["Select Option...","Edit","Delete"]
cAddRecord = "Add Record"
cEditRecord = "Edit Record"
cRecordDeleted = "Record Deleted!"
aMovePages = ["First","Prev","Next","Last"]
cPage = "Page"
cOf = "of"
cRecordsCount = "Records Count"
cSave = "Save"
temp = new page
cTextAlign = temp.StyleTextRight()
cNoRecords = "No records!"
Screen Shot:
47.21. CRUD Example using MVC 386

3. Ring Documentation, Release 1.5.1
47.22 Users registration and Login
We have the users classes (Model, View & Controller) to deal with the users data like username & email.
The next code is stored in ex25_users.ring
Class UsersModel from ModelBase
cSearchColumn = "username"
Class UsersController From ControllerBase
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4. Ring Documentation, Release 1.5.1
aColumnsNames = ["id","username","email"]
Func UpdateRecord
oModel.id = aPageVars[cRecID]
oModel.updatecolumn("username", aPageVars[:username] )
oModel.updatecolumn("email", aPageVars[:email] )
oView.UpdateView(self)
Class UsersView from ViewBase
oLanguage = new UsersLanguageEnglish
Func AddFuncScript oPage,oController
return oPage.scriptfunc("myadd",oPage.scriptredirection("ex26.ring"))
Func FormViewContent oController,oTranslation,oPage
return [
[oTranslation.aColumnsTitles[2],"textbox","username",
oController.oModel.UserName,oPage.stylewidth("100%")],
[oTranslation.aColumnsTitles[3],"textbox","email",
oController.oModel.Email,oPage.stylewidth("50%")]
]
Class UsersLanguageEnglish
cTitle = "Users Table"
cBack = "back"
aColumnsTitles = ["ID","User Name","Email"]
cOptions = "Options"
cSearch = "Search"
comboitems = ["Select Option...","Edit","Delete"]
cAddRecord = "Add Record"
cEditRecord = "Edit Record"
cRecordDeleted = "Record Deleted!"
aMovePages = ["First","Prev","Next","Last"]
cPage = "Page"
cOf = "of"
cRecordsCount = "Records Count"
cSave = "Save"
temp = new page
cTextAlign = temp.StyleTextRight()
cNoRecords = "No records!"
In the file ex25.ring we load ex25_users.ring then create an object from UsersController class.
Using the created object, we call the routing method.
#!c:ringbinring.exe -cgi
Load "weblib.ring"
Load "datalib.ring"
Load "ex25_users.ring"
Import System.Web
website = "ex25.ring"
New UsersController { Routing() }
Screen Shot:
47.22. Users registration and Login 388

5. Ring Documentation, Release 1.5.1
See the next code for the registration page
#!c:ringbinring.exe -cgi
Load "weblib.ring"
Load "datalib.ring"
Import System.Web
website = "ex26.ring"
new page {
boxstart()
text( "Register")
newline()
boxend()
divstart([:style = stylegradient(6) + stylesize("100%","95%") ])
link([ :url = website, :title = "back" , :style = stylecolor("white")])
newline()
divstart([ :style= styledivcenter("500","160") + stylegradient(52) ])
formpost("ex27.ring")
tablestart([ :Style = stylemarginleft("2%") + stylemargintop("2%") +
stylewidth("90%") ])
rowstart([])
cellstart([:style = stylewidth("20%") + styleheight(30)])
text("User Name")
cellend()
cellstart([ :style = stylewidth("80%") ])
textbox([:name = "username", :style = stylewidth("100%")])
cellend()
rowend()
rowstart([])
cellstart([ :Style = styleheight(30)])
text("Password")
cellend()
cellstart([])
textbox([:name = "password" , :type = "password"])
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6. Ring Documentation, Release 1.5.1
cellend()
rowend()
rowstart([])
cellstart([ :style = styleheight(30)])
text("Email")
cellend()
cellstart([])
textbox([:name = "email" , :style = stylewidth("100%")])
cellend()
rowend()
rowstart([])
cellstart([ :style = styleheight(30)])
cellend()
cellstart([ :style = styleheight(30)])
submit([:value = "Register" ])
cellend()
rowend()
tableend()
formend()
divend()
divend()
}
Screen Shot:
The Registration response
#!c:ringbinring.exe -cgi
Load "weblib.ring"
Load "datalib.ring"
Load "ex25_users.ring"
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7. Ring Documentation, Release 1.5.1
Import System.Web
oUser = new UsersModel
oUser.Connect()
if oUser.findwith("username",aPageVars["username"])
new page {
text("The user name is already registered")
}
return
ok
if oUser.findwith("email",aPageVars["email"])
new page {
text("This email is already registered")
}
return
ok
aPageVars["salt"] = str2hex(RandBytes(32))
aPageVars["pwhash"] = sha256(aPagevars["password"]+aPageVars["salt"])
aPageVars["sessionid"] = str2hex(randbytes(32))
oUser.Insert()
new page {
cookie("sessionid",aPageVars["sessionid"])
text("New User Created!")
newline()
text("User Name : " + aPageVars["username"])
newline()
}
oUser.Disconnect()
See the next code for the Login page
#!c:ringbinring.exe -cgi
Load "weblib.ring"
Load "datalib.ring"
Import System.Web
website = "ex28.ring"
new page {
boxstart()
text( "Login")
newline()
boxend()
divstart([:style = stylegradient(6) + stylesize("100%","95%") ])
link([ :url = website, :title = "back" , :style = stylecolor("white")])
newline()
divstart([ :style= styledivcenter("500","130") + stylegradient(52) ])
formpost("ex29.ring")
tablestart([ :Style = stylemarginleft("2%") + stylemargintop("2%") +
stylewidth("90%") ])
rowstart([])
cellstart([:style = stylewidth("20%") + styleheight(30)])
text("User Name")
cellend()
cellstart([ :style = stylewidth("80%") ])
textbox([:name = "username", :style = stylewidth("100%")])
cellend()
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8. Ring Documentation, Release 1.5.1
rowend()
rowstart([])
cellstart([ :style = styleheight(30)])
text("Password")
cellend()
cellstart([])
textbox([:name = "password" , :type = "password"])
cellend()
rowend()
rowstart([])
cellstart([ :style = styleheight(30) ])
cellend()
cellstart([])
submit([:value = "Login" ])
cellend()
rowend()
tableend()
formend()
divend()
divend()
}
Screen Shot:
The response page
#!c:ringbinring.exe -cgi
Load "weblib.ring"
Load "datalib.ring"
Load "ex25_users.ring"
Import System.Web
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9. Ring Documentation, Release 1.5.1
oUser = new UsersModel
oUser.Connect()
lResult = oUser.FindWith("username",aPageVars["username"])
new page {
if lResult
if sha256(aPagevars["password"]+oUser.Salt) = oUser.pwhash
text ("Correct Password!")
aPageVars["sessionid"] = str2hex(randbytes(32))
oUser.UpdateColumn("sessionid",aPageVars["sessionid"])
cookie("sessionid",aPageVars["sessionid"])
else
text ("Bad password!")
ok
else
text("Bad User Name!")
ok
}
oUser.Disconnect()
The next code for checking if the user needs to login or not
#!c:ringbinring.exe -cgi
Load "weblib.ring"
Load "datalib.ring"
Load "ex25_users.ring"
Import System.Web
oUser = new UsersModel
oUser.Connect()
lResult = oUser.FindWith("sessionid",aPageVars["sessionid"])
new page {
if lResult
text("User Name : " + oUser.username )
else
text("Please Login First!")
ok
}
oUser.Disconnect()
47.23 Database, ModelBase & ControllerBase classes
In this section we will see some code from datalib.ring
The next code presents the Database, ModelBase & ControllerBase classes
Import System.Web
Class Database
cServer = "localhost"
cUserName = "root"
cPassword = "root"
cDatabase = "mahdb"
Func Connect
47.23. Database, ModelBase & ControllerBase classes 393

10. Ring Documentation, Release 1.5.1
con = mysql_init()
mysql_connect(con, cServer, cUserName, cPassWord,cDatabase)
Func Disconnect
mysql_close(con)
Func Query cQuery
mysql_query(con,cQuery)
Func QueryResult
return mysql_result(con)
Func QueryResultWithColumns
# return columns names + query result
return mysql_result2(con)
Func QueryValue
aResult = mysql_result(con)
if islist(aResult) and len(aResult) >= 1
aResult = aResult[1]
if len(aResult) >= 1
return aResult[1]
ok
ok
return 0
Func EscapeString x
if isstring(x)
return MySQL_Escape_String(con,x)
else
return MySQL_Escape_String(con,string(x))
ok
Private
con = NULL
Class ModelBase from Database
cTableName = ""
cSearchColumn = "name"
aColumns = []
aQueryResult = []
ID = 0
# set table name from class name
classname = lower(classname(self))
if right(classname,5) = :model
cTablename = left(classname,len(classname)-5)
ok
Func Insert
cValues = ""
for x in aColumns
cValues += "'" + EscapeString(aPageVars[x]) + "',"
47.23. Database, ModelBase & ControllerBase classes 394