This short article is a result of the following Twitter activity:
So let’s do it! First of all, you have to install GoLang: https://golang.org/doc/install
Once this is done, we can create a Go program to send emails. We will use "gopkg.in/mail.v2″ to make it simple.
Below you can find a simple GoLang code to send an email.
5 gomail "gopkg.in/mail.v2"
10 smtpHost string = "my.smtp.server.pl"
12 smtpUser string = "my.user@ora-600.pl"
13 smtpPass string = "Xtr3mly53c23tP@ssw02d"
17func sendEmail(mailSendTo *C.char, mailSubject *C.char, mailBody *C.char) *C.char {
19 var sendTo = C.GoString(mailSendTo)
20 var subject = C.GoString(mailSubject)
21 var body = C.GoString(mailBody)
22 m := gomail.NewMessage()
24 m.SetHeader("From", smtpUser)
26 m.SetHeader("To", sendTo)
28 m.SetHeader("Subject", subject)
30 m.SetBody("text/html", body)
32 d := gomail.NewDialer(smtpHost, smtpPort, smtpUser, smtpPass)
35 d.TLSConfig = &tls.Config{InsecureSkipVerify: true}
37 if err := d.DialAndSend(m); err != nil {
38 return C.CString(err.Error())
40 return C.CString("ok")
I put explanation of the code in the comments.
Now, let’s build the package:
1[oracle@b3124c94c1c7 ~]$ go mod init sendemail
2go: creating new go.mod: module sendemail
3go: to add module requirements and sums:
5[oracle@b3124c94c1c7 ~]$ go mod tidy
6go: finding module for package gopkg.in/mail.v2
7go: downloading gopkg.in/mail.v2 v2.3.1
8go: found gopkg.in/mail.v2 in gopkg.in/mail.v2 v2.3.1
9go: finding module for package gopkg.in/alexcesaro/quotedprintable.v3
10go: downloading gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0-20150716171945-2caba252f4dc
11go: found gopkg.in/alexcesaro/quotedprintable.v3 in gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0-20150716171945-2caba252f4dc
12[oracle@b3124c94c1c7 ~]$ go build -o sendemail.so -buildmode=c-shared
This operation should create the sendemail.so shared object and it’s header file sendemail.h:
1[oracle@b3124c94c1c7 ~]$ file sendemail.so
2sendemail.so: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, BuildID[sha1]=f0eb77f5f5dd817b59837f7793d3afa43fe8fa0b, not stripped
We can copy sendemail.so to $ORACLE_HOME/lib or put it in some other directory and add the following line to the $ORACLE_HOME/hs/admin/extproc.ora file:
1SET EXTPROC_DLLS=ONLY:/home/oracle/extproc/sendemail.so
This line will let use use your shared SO file.
Now, we can create the appropriate database objects:
1SQL> create or replace library lib_sendemail as '/home/oracle/extproc/sendemail.so';
6SQL> create or replace function f_sendemail(p_to varchar2, p_subcject varchar2, p_body varchar2) return varchar2 as
9 4 library lib_sendemail
And we are ready to send the email from our external procedure! 😀
1SQL> select f_sendemail('kamil@ora-600.pl', 'jebacpis', 'And that''s it folks!') from dual;
3F_SENDEMAIL('KAMIL@ORA-600.PL','JEBACPIS','ANDTHAT''SITFOLKS!')
Integrating the power of GoLang and Oracle together may bring some fun features 😉 Have fun with external procedures!
