My app can use PostgreSQL and – optionally – SQLite. I would like to be
able to compile the app without cgo when SQLite isn't used, as this
removes the need for a C compiler which makes builds easier and faster,
especially for end-users.
In the simple case, this is not a problem go-sqlite3 already provides a
simple non-cgo mock so it compiles and gives a runtime error if you try
to use it anyway.
However, now I'd like to register a function for my SQLite connection to
match a PostgreSQL function like so:
sql.Register("sqlite3_custom", &sqlite3.SQLiteDriver{
ConnectHook: func(conn *sqlite3.SQLiteConn) error {
return conn.RegisterFunc("pow", pow, true); err != nil {
},
})
But this makes it quite hard to keep the same logic since it refers to
types that don't exist with CGO_ENABLED=0. I will need to create a db.go
with `+build !cgo` and db_cgo.go with `+buid cgo` which duplicates all
the logic but with the sqlite hooks. In my case, this actually affects
quite a lot; for example I have a helper function which connects and
runs migrations and whatnot which looks like:
type ConnectOptions struct {
Connect string // Connect string.
Schema []byte // Database schema to create on startup.
Migrate *Migrate
SQLiteHook func(*sqlite3.SQLiteConn) error
}
And I'd have to have two versions of that, too. You could perhaps do
something with interfaces, but because the sql.Register() call above
references the `sqlite3.SQLiteDriver.ConnectHook` struct field that's
not so straightforward (and wrapping stuff in interfaces probably won't
do much for the general clarity either).
This simplifies all of that by providing some common types that may be
used when setting up a SQLite connectin. I renamed the
`SQLiteDriverMock` to `&SQLiteDriver` for this reason. As far as I can
tell in my testing, this has no real downsides (but perhaps I missed
something?)
---
Note: it might also be worth doing something similar for error.go, as I
already have two variants of the below function (one with cgo as below,
and one without cgo which checks just PostgreSQL):
// ErrUnique reports if this error reports a UNIQUE constraint violation.
//
// This is the cgo version which works for PostgreSQL and SQLite.
func ErrUnique(err error) bool {
var sqlErr *sqlite3.Error
if errors.As(err, &sqlErr) && sqlErr.ExtendedCode == sqlite3.ErrConstraintUnique {
return true
}
var pqErr *pq.Error
if errors.As(err, &pqErr) && pqErr.Code == "23505" {
return true
}
return false
}
This is a lot more manageable than the ConnectHook case, but it would be
nicer if it would work without the need for build tags.
* Allow unused named parameters
Try to bind all named parameters and ignore those not used.
* Allow "@" and "$" for named parameters
* Add tests for named parameters
Co-authored-by: Guido Berhoerster <guido+go-sqlite3@berhoerster.name>
Once the regex encountered the first instance of a non-match, it would return without processing the rest of the rows in the statement. This change allows it to process the remaining, only setting the sqlite3_result_int to zero then continuing. This worked fine for the example as it only had one item to process.
* adding SystemErrno to Error, and fixing error logic when open fails
* fix for old versions of libsqlite3 that do not have sqlite3_system_errno defined
* fixing pre-processor logic
[why]
see https://github.com/mattn/go-sqlite3/issues/607
SQLite default journal mode is DELETE, but forcing it on open causes "database is locked"
if other connection exists with WAL mode, for example.
[how]
Don't set DELETE mode if not set in DSN explicitly.
[testing]
Run tests in my project where WAL mode is used.
[why]
Context cancellation goroutine is not in sync with Next() method lifetime.
It leads to sql.ErrNoRows instead of context.Canceled often (easy to reproduce).
It leads to interruption of next query executed on same connection (harder to reproduce).
[how]
Do query in goroutine, wait when interruption done.
[testing]
Add unit test that reproduces error cases.
When building on darwin with the `libsqlite3` tag, go-sqlite3 adds the
homebrew library path. It does not, however, add the homebrew include
path, which means that the MacOS sqlite3 header is used instead. On
my system, this results in build errors that look like this:
./sqlite3_load_extension.go:25:8: could not determine kind of name for C.sqlite3_enable_load_extension
./sqlite3_load_extension.go:33:8: could not determine kind of name for C.sqlite3_load_extension
Add the homebrew include path as well, so that he header matches the
libraries we're using.
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Martin Tournoij