nwaku/waku/common/sqlite/database.nim

342 lines
9.7 KiB
Nim

{.push raises: [].}
# The code in this file is an adaptation of the Sqlite KV Store found in nim-eth.
# https://github.com/status-im/nim-eth/blob/master/eth/db/kvstore_sqlite3.nim
#
# Most of it is a direct copy, the only unique functions being `get` and `put`.
import
std/os,
stew/results,
chronicles,
sqlite3_abi
logScope:
topics = "sqlite"
type
Sqlite = ptr sqlite3
NoParams* = tuple
RawStmtPtr* = ptr sqlite3_stmt
SqliteStmt*[Params; Result] = distinct RawStmtPtr
AutoDisposed[T: ptr|ref] = object
val: T
template dispose(db: Sqlite) =
discard sqlite3_close(db)
template dispose(rawStmt: RawStmtPtr) =
discard sqlite3_finalize(rawStmt)
template dispose*(sqliteStmt: SqliteStmt) =
discard sqlite3_finalize(RawStmtPtr sqliteStmt)
proc release[T](x: var AutoDisposed[T]): T =
result = x.val
x.val = nil
proc disposeIfUnreleased[T](x: var AutoDisposed[T]) =
mixin dispose
if x.val != nil:
dispose(x.release)
template checkErr*(op, cleanup: untyped) =
if (let v = (op); v != SQLITE_OK):
cleanup
return err($sqlite3_errstr(v))
template checkErr*(op) =
checkErr(op): discard
type
DatabaseResult*[T] = Result[T, string]
SqliteDatabase* = ref object of RootObj
env*: Sqlite
type DataProc* = proc(s: RawStmtPtr) {.closure.} # the nim-eth definition is different; one more indirection
const NoopRowHandler* = proc(s: RawStmtPtr) {.closure.} = discard
proc new*(T: type SqliteDatabase, path: string, readOnly=false): DatabaseResult[T] =
var env: AutoDisposed[ptr sqlite3]
defer: disposeIfUnreleased(env)
let flags = if readOnly: SQLITE_OPEN_READONLY
else: SQLITE_OPEN_READWRITE or SQLITE_OPEN_CREATE
if path != ":memory:":
try:
createDir(parentDir(path))
except OSError, IOError:
return err("sqlite: cannot create database directory")
checkErr sqlite3_open_v2(path, addr env.val, flags.cint, nil)
template prepare(q: string, cleanup: untyped): ptr sqlite3_stmt =
var s: ptr sqlite3_stmt
checkErr sqlite3_prepare_v2(env.val, q, q.len.cint, addr s, nil):
cleanup
s
template checkExec(s: ptr sqlite3_stmt) =
if (let x = sqlite3_step(s); x != SQLITE_DONE):
discard sqlite3_finalize(s)
return err($sqlite3_errstr(x))
if (let x = sqlite3_finalize(s); x != SQLITE_OK):
return err($sqlite3_errstr(x))
template checkExec(q: string) =
let s = prepare(q): discard
checkExec(s)
template checkWalPragmaResult(journalModePragma: ptr sqlite3_stmt) =
if (let x = sqlite3_step(journalModePragma); x != SQLITE_ROW):
discard sqlite3_finalize(journalModePragma)
return err($sqlite3_errstr(x))
if (let x = sqlite3_column_type(journalModePragma, 0); x != SQLITE3_TEXT):
discard sqlite3_finalize(journalModePragma)
return err($sqlite3_errstr(x))
if (let x = sqlite3_column_text(journalModePragma, 0);
x != "memory" and x != "wal"):
discard sqlite3_finalize(journalModePragma)
return err("Invalid pragma result: " & $x)
let journalModePragma = prepare("PRAGMA journal_mode = WAL;"): discard
checkWalPragmaResult(journalModePragma)
checkExec(journalModePragma)
ok(SqliteDatabase(env: env.release))
template prepare*(env: Sqlite, q: string, cleanup: untyped): ptr sqlite3_stmt =
var s: ptr sqlite3_stmt
checkErr sqlite3_prepare_v2(env, q, q.len.cint, addr s, nil):
cleanup
s
proc bindParam*(s: RawStmtPtr, n: int, val: auto): cint =
when val is openarray[byte]|seq[byte]:
if val.len > 0:
sqlite3_bind_blob(s, n.cint, unsafeAddr val[0], val.len.cint, nil)
else:
sqlite3_bind_blob(s, n.cint, nil, 0.cint, nil)
elif val is int32:
sqlite3_bind_int(s, n.cint, val)
elif val is uint32:
sqlite3_bind_int64(s, n.cint, val)
elif val is int64:
sqlite3_bind_int64(s, n.cint, val)
elif val is float64:
sqlite3_bind_double(s, n.cint, val)
# Note: bind_text not yet supported in sqlite3_abi wrapper
# elif val is string:
# sqlite3_bind_text(s, n.cint, val.cstring, -1, nil) # `-1` implies string length is the number of bytes up to the first null-terminator
else:
{.fatal: "Please add support for the '" & $typeof(val) & "' type".}
template bindParams(s: RawStmtPtr, params: auto) =
when params is tuple:
var i = 1
for param in fields(params):
checkErr bindParam(s, i, param)
inc i
else:
checkErr bindParam(s, 1, params)
proc exec*[P](s: SqliteStmt[P, void], params: P): DatabaseResult[void] =
let s = RawStmtPtr s
bindParams(s, params)
let res =
if (let v = sqlite3_step(s); v != SQLITE_DONE):
err($sqlite3_errstr(v))
else:
ok()
# release implict transaction
discard sqlite3_reset(s) # same return information as step
discard sqlite3_clear_bindings(s) # no errors possible
res
template readResult(s: RawStmtPtr, column: cint, T: type): auto =
when T is Option:
if sqlite3_column_type(s, column) == SQLITE_NULL:
none(typeof(default(T).get()))
else:
some(readSimpleResult(s, column, typeof(default(T).get())))
else:
readSimpleResult(s, column, T)
template readResult(s: RawStmtPtr, T: type): auto =
when T is tuple:
var res: T
var i = cint 0
for field in fields(res):
field = readResult(s, i, typeof(field))
inc i
res
else:
readResult(s, 0.cint, T)
proc exec*[Params, Res](s: SqliteStmt[Params, Res],
params: Params,
onData: DataProc): DatabaseResult[bool] =
let s = RawStmtPtr s
bindParams(s, params)
try:
var gotResults = false
while true:
let v = sqlite3_step(s)
case v
of SQLITE_ROW:
onData(s)
gotResults = true
of SQLITE_DONE:
break
else:
return err($sqlite3_errstr(v))
return ok gotResults
finally:
# release implicit transaction
discard sqlite3_reset(s) # same return information as step
discard sqlite3_clear_bindings(s) # no errors possible
proc query*(db: SqliteDatabase, query: string, onData: DataProc): DatabaseResult[bool] =
var s = prepare(db.env, query): discard
try:
var gotResults = false
while true:
let v = sqlite3_step(s)
case v
of SQLITE_ROW:
onData(s)
gotResults = true
of SQLITE_DONE:
break
else:
return err($sqlite3_errstr(v))
return ok gotResults
finally:
# release implicit transaction
discard sqlite3_reset(s) # same return information as step
discard sqlite3_clear_bindings(s) # no errors possible
discard sqlite3_finalize(s) # NB: dispose of the prepared query statement and free associated memory
proc prepareStmt*(
db: SqliteDatabase,
stmt: string,
Params: type,
Res: type
): DatabaseResult[SqliteStmt[Params, Res]] =
var s: RawStmtPtr
checkErr sqlite3_prepare_v2(db.env, stmt, stmt.len.cint, addr s, nil)
ok SqliteStmt[Params, Res](s)
proc close*(db: SqliteDatabase) =
discard sqlite3_close(db.env)
db[] = SqliteDatabase()[]
## Maintenance procedures
# TODO: Cache this value in the SqliteDatabase object.
# Page size should not change during the node execution time
proc getPageSize*(db: SqliteDatabase): DatabaseResult[int64] =
## Query or set the page size of the database. The page size must be a power of
## two between 512 and 65536 inclusive.
var size: int64
proc handler(s: RawStmtPtr) =
size = sqlite3_column_int64(s, 0)
let res = db.query("PRAGMA page_size;", handler)
if res.isErr():
return err("failed to get page_size")
ok(size)
proc getFreelistCount*(db: SqliteDatabase): DatabaseResult[int64] =
## Return the number of unused pages in the database file.
var count: int64
proc handler(s: RawStmtPtr) =
count = sqlite3_column_int64(s, 0)
let res = db.query("PRAGMA freelist_count;", handler)
if res.isErr():
return err("failed to get freelist_count")
ok(count)
proc getPageCount*(db: SqliteDatabase): DatabaseResult[int64] =
## Return the total number of pages in the database file.
var count: int64
proc handler(s: RawStmtPtr) =
count = sqlite3_column_int64(s, 0)
let res = db.query("PRAGMA page_count;", handler)
if res.isErr():
return err("failed to get page_count")
ok(count)
proc vacuum*(db: SqliteDatabase): DatabaseResult[void] =
## The VACUUM command rebuilds the database file, repacking it into a minimal amount of disk space.
let res = db.query("VACUUM;", NoopRowHandler)
if res.isErr():
return err("vacuum failed")
ok()
## Database scheme versioning
proc getUserVersion*(database: SqliteDatabase): DatabaseResult[int64] =
## Get the value of the user-version integer.
##
## The user-version is an integer that is available to applications to use however they want.
## SQLite makes no use of the user-version itself. This integer is stored at offset 60 in
## the database header.
##
## For more info check: https://www.sqlite.org/pragma.html#pragma_user_version
var version: int64
proc handler(s: ptr sqlite3_stmt) =
version = sqlite3_column_int64(s, 0)
let res = database.query("PRAGMA user_version;", handler)
if res.isErr():
return err("failed to get user_version")
ok(version)
proc setUserVersion*(database: SqliteDatabase, version: int64): DatabaseResult[void] =
## Set the value of the user-version integer.
##
## The user-version is an integer that is available to applications to use however they want.
## SQLite makes no use of the user-version itself. This integer is stored at offset 60 in
## the database header.
##
## For more info check: https://www.sqlite.org/pragma.html#pragma_user_version
let query = "PRAGMA user_version=" & $version & ";"
let res = database.query(query, NoopRowHandler)
if res.isErr():
return err("failed to set user_version")
ok()