palladum-lightning/plugins/bkpr/db.c

#include "config.h"
#include <ccan/array_size/array_size.h>
#include <ccan/tal/str/str.h>
#include <common/daemon.h>
#include <db/bindings.h>
#include <db/common.h>
#include <db/exec.h>
#include <db/utils.h>
#include <plugins/bkpr/db.h>
#include <plugins/libplugin.h>
#include <stdio.h>

struct migration {
	const char *sql;
	void (*func)(struct plugin *p, struct db *db);
};

/* Do not reorder or remove elements from this array.
 * It is used to migrate existing databases from a prevoius state, based on
 * string indices */
static struct migration db_migrations[] = {
	{SQL("CREATE TABLE version (version INTEGER);"), NULL},
	{SQL("INSERT INTO version VALUES (1);"), NULL},
	{SQL("CREATE TABLE vars ("
		"  name TEXT"
		", val TEXT"
		", intval INTEGER"
		", blobval BLOB"
		", PRIMARY KEY (name)"
		");"),
	NULL},
	{SQL("INSERT INTO vars ("
		"  name"
		", intval"
		") VALUES ("
		" 'data_version'"
		", 0"
		");"),
	NULL},
	{NULL, NULL},
	{SQL("CREATE TABLE chain_events ("
		"  id BIGSERIAL"
		", account_name TEXT"
		", tag TEXT"
		", credit BIGINT"
		", debit BIGINT"
		", output_value BIGINT"
		", currency TEXT"
		", timestamp BIGINT"
		", blockheight INTEGER"
		", utxo_txid BLOB"
		", outnum INTEGER"
		", payment_id BLOB"
		", spending_txid BLOB"
		", PRIMARY KEY (id)"
		");"),
	NULL},
	{SQL("CREATE TABLE channel_events ("
		"  id BIGSERIAL"
		", account_name TEXT"
		", tag TEXT"
		", credit BIGINT"
		", debit BIGINT"
		", fees BIGINT"
		", currency TEXT"
		", payment_id BLOB"
		", part_id INTEGER"
		", timestamp BIGINT"
		", PRIMARY KEY (id)"
		");"),
	NULL},
	{NULL, NULL}, /* onchain_fees table */
	{SQL("ALTER TABLE chain_events ADD origin TEXT;"), NULL},
	{NULL, NULL},
	{SQL("ALTER TABLE chain_events ADD ignored INTEGER;"), NULL},
	{SQL("ALTER TABLE chain_events ADD stealable INTEGER;"), NULL},
	{SQL("ALTER TABLE chain_events ADD ev_desc TEXT DEFAULT NULL;"), NULL},
	{SQL("ALTER TABLE channel_events ADD ev_desc TEXT DEFAULT NULL;"), NULL},
	{SQL("ALTER TABLE channel_events ADD rebalance_id BIGINT DEFAULT NULL;"), NULL},
	{SQL("ALTER TABLE chain_events ADD spliced INTEGER DEFAULT 0;"), NULL},
	{NULL, NULL},
	{NULL, NULL},
	/* We used to send anchors to the wallet, but set ignored tag.  Now we send
	 * them to external. */
	{SQL("UPDATE chain_events"
	     " SET account_name = 'external'"
	     " WHERE account_name = 'wallet'"
	     " AND ignored = 1"), NULL},
};

static bool db_migrate(struct plugin *p, struct db *db)
{
	/* Read current version from database */
	int current, orig, available;
	struct db_stmt *stmt;

	orig = current = db_get_version(db);
	available = ARRAY_SIZE(db_migrations) - 1;

	if (current == -1) {
		plugin_log(p, LOG_INFORM, "Creating database");
	} else if (available < current)
		plugin_err(p,
			   "Refusing to migrate down from version %u to %u",
			   current, available);
	else if (current != available)
		plugin_log(p, LOG_INFORM,
			   "Updating database from version %u to %u",
			   current, available);

	while (current < available) {
		current++;
		if (db_migrations[current].sql) {
			stmt = db_prepare_v2(db, db_migrations[current].sql);
			db_exec_prepared_v2(take(stmt));
		}
		if (db_migrations[current].func)
			db_migrations[current].func(p, db);
	}

	/* Finally, update the version number in the version table */
	stmt = db_prepare_v2(db, SQL("UPDATE version SET version=?;"));
	db_bind_int(stmt, available);
	db_exec_prepared_v2(take(stmt));

	return current != orig;
}

static void db_error(struct plugin *plugin, bool fatal, const char *fmt, va_list ap)
{
	if (fatal) {
		const char *msg = tal_vfmt(tmpctx, fmt, ap);
		send_backtrace(msg);
		plugin_err(plugin, "%s", msg);
	}
	else
		plugin_logv(plugin, LOG_BROKEN, fmt, ap);
}

struct db *db_setup(const tal_t *ctx, struct plugin *p,
		    const char *db_dsn)
{
	bool migrated;
	struct db *db;

	db = db_open(ctx, db_dsn, plugin_developer_mode(p), db_error, p);
	db->report_changes_fn = NULL;

	db_begin_transaction(db);
	migrated = db_migrate(p, db);
	db->data_version = db_data_version_get(db);
	db_commit_transaction(db);

	/* This needs to be done outside a transaction, apparently.
	 * It's a good idea to do this every so often, and on db
	 * upgrade is a reasonable time. */
	if (migrated && !db->config->vacuum_fn(db))
		db_fatal(db, "Error vacuuming db: %s", db->error);

	return db;
}