1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
//! Session pool nonblocking mode implementation
use super::{SessionPool, SPool};
use crate::{Session, Result, oci::{self, *}, Environment, task};
use std::{ptr, slice, str, marker::PhantomData, sync::Arc};
impl SPool {
pub(crate) async fn new(env: &Environment, dblink: &str, username: &str, password: &str, min: usize, inc: usize, max: usize, session_state_fixup_callback: &str) -> Result<Self> {
let err = Handle::<OCIError>::new(&env)?;
let pool = Handle::<OCISPool>::new(&env)?;
let info = Handle::<OCIAuthInfo>::new(&env)?;
info.set_attr(OCI_ATTR_DRIVER_NAME, "sibyl", &err)?;
if session_state_fixup_callback.len() > 0 {
info.set_attr(OCI_ATTR_FIXUP_CALLBACK, session_state_fixup_callback, &err)?;
}
pool.set_attr(OCI_ATTR_SPOOL_AUTH, info.get_ptr(), &err)?;
let mut spool = Self { pool, info, err, env: env.get_env(), name: Vec::new() };
let dblink = String::from(dblink);
let username = String::from(username);
let password = String::from(password);
task::execute_blocking(move || -> Result<Self> {
let mut pool_name_ptr = ptr::null::<u8>();
let mut pool_name_len = 0u32;
oci::session_pool_create(
spool.env.as_ref(), spool.err.as_ref(), spool.pool.as_ref(),
&mut pool_name_ptr, &mut pool_name_len,
dblink.as_ptr(), dblink.len() as _,
min as _, max as _, inc as _,
username.as_ptr(), username.len() as _,
password.as_ptr(), password.len() as _,
OCI_SPC_HOMOGENEOUS | OCI_SPC_STMTCACHE
)?;
let name = unsafe {
slice::from_raw_parts(pool_name_ptr, pool_name_len as usize)
};
spool.name.extend_from_slice(name);
Ok(spool)
}).await?
}
}
impl<'a> SessionPool<'a> {
pub(crate) async fn new(env: &'a Environment, dblink: &str, username: &str, password: &str, min: usize, inc: usize, max: usize, session_state_fixup_callback: &str) -> Result<SessionPool<'a>> {
let inner = SPool::new(env, dblink, username, password, min, inc, max, session_state_fixup_callback).await?;
let inner = Arc::new(inner);
Ok(Self { inner, phantom_env: PhantomData })
}
/**
Returns a default (untagged) session from this session pool.
# Example
```
use sibyl::{Environment, Session, Date, Result};
use once_cell::sync::OnceCell;
use std::{env, sync::Arc};
fn main() -> Result<()> {
// `sibyl::block_on` is used to run Sibyl's async doc tests
// and would not be used when `main` can be declared as async.
sibyl::block_on(async {
static ORACLE : OnceCell<Environment> = OnceCell::new();
let oracle = ORACLE.get_or_try_init(|| {
Environment::new()
})?;
let dbname = env::var("DBNAME").expect("database name");
let dbuser = env::var("DBUSER").expect("user name");
let dbpass = env::var("DBPASS").expect("password");
let pool = oracle.create_session_pool(&dbname, &dbuser, &dbpass, 0, 1, 4).await?;
let pool = Arc::new(pool);
let mut workers = Vec::with_capacity(10);
for _i in 0..workers.capacity() {
let pool = pool.clone();
// `sibyl::spawn` abstracts `spawn` for Sibyl's use with different async
// runtimes. One does not need it when a specific runtime is selected.
let handle = sibyl::spawn(async move {
let session = pool.get_session().await?;
select_latest_hire(&session).await
});
workers.push(handle);
}
for handle in workers {
let worker_result = handle.await;
#[cfg(any(feature="tokio", feature="actix"))]
let worker_result = worker_result.expect("completed task result");
let name = worker_result?;
assert_eq!(name, "Amit Banda was hired on April 21, 2008");
}
Ok(())
})
}
async fn select_latest_hire(session: &Session<'_>) -> Result<String> {
let stmt = session.prepare("
SELECT first_name, last_name, hire_date
FROM (
SELECT first_name, last_name, hire_date
, Row_Number() OVER (ORDER BY hire_date DESC, last_name) AS hire_date_rank
FROM hr.employees
)
WHERE hire_date_rank = 1
").await?;
if let Some( row ) = stmt.query_single(()).await? {
let first_name : Option<&str> = row.get(0)?;
let last_name : &str = row.get(1)?;
let name = first_name.map_or(last_name.to_string(), |first_name| format!("{} {}", first_name, last_name));
let hire_date : Date = row.get(2)?;
let hire_date = hire_date.to_string("FMMonth DD, YYYY")?;
Ok(format!("{} was hired on {}", name, hire_date))
} else {
Ok("Not found".to_string())
}
}
```
*/
pub async fn get_session(&self) -> Result<Session<'_>> {
let (session, _found) = Session::from_session_pool(self, "").await?;
Ok(session)
}
/**
Returns a tagged session, i.e. a session with the specified type/tag.
The tags provide a way to customize sessions in the pool. A client can get a default or untagged
session from a pool, set certain attributes on the session (such as globalization settings) and
label it with an appropriate tag.
This session or a session with the same attributes can then be requested by providing the same
tag that was used during session customization.
If a user asks for a session with tag 'A', and a matching session is not available, an appropriately
authenticated untagged session is returned, if such a session is free.
# Parameters
- `taginfo` - Either a single or a [Multi-Property Tag](https://docs.oracle.com/en/database/oracle/oracle-database/19/lnoci/session-and-connection-pooling.html#GUID-DFA21225-E83C-4177-A79A-B8BA29DC662C).
# Returns
A tuple with the returned session and the boolean flag. The flag indicates whether the type of the returned
session is the same as requested.
# Example
```
# fn main() -> sibyl::Result<()> {
# sibyl::block_on(async {
# use once_cell::sync::OnceCell;
# static ORACLE: OnceCell<sibyl::Environment> = OnceCell::new();
# let oracle = ORACLE.get_or_try_init(|| sibyl::Environment::new())?;
# let dbname = std::env::var("DBNAME").expect("database name");
# let dbuser = std::env::var("DBUSER").expect("user name");
# let dbpass = std::env::var("DBPASS").expect("password");
let pool = oracle.create_session_pool(&dbname, &dbuser, &dbpass, 0, 1, 5).await?;
{
let (session,found) = pool.get_tagged_session("CUSTOM").await?;
assert!(!found, "a default (not yet tagged) session was returned");
if !found {
# let stmt = session.prepare("SELECT value FROM nls_session_parameters WHERE parameter=:PARAM_NAME").await?;
# let row = stmt.query_single("NLS_DATE_FORMAT").await?.expect("one row");
# let fmt: &str = row.get(0)?;
# assert_ne!(fmt, "YYYY-MM-DD", "Default NLS_DATE_FORMAT differs from what we want to set");
let stmt = session.prepare("ALTER SESSION SET NLS_DATE_FORMAT='YYYY-MM-DD'").await?;
stmt.execute(()).await?;
session.set_tag("CUSTOM")?;
}
} // session is released back to the pool here
{
let (session,found) = pool.get_tagged_session("CUSTOM").await?;
assert!(found, "the customized session was returned");
let stmt = session.prepare("SELECT value FROM nls_session_parameters WHERE parameter=:PARAM_NAME").await?;
let row = stmt.query_single("NLS_DATE_FORMAT").await?.expect("one row");
let fmt: &str = row.get(0)?;
assert_eq!(fmt, "YYYY-MM-DD", "Session uses custom NLS_DATE_FORMAT");
}
# Ok(()) })
# }
```
*/
pub async fn get_tagged_session(&self, taginfo: &str) -> Result<(Session<'_>,bool)> {
Session::from_session_pool(self, taginfo).await
}
}