/* 2022-07-22 The author disclaims copyright to this source code. In place of a legal notice, here is a blessing: * May you do good and not evil. * May you find forgiveness for yourself and forgive others. * May you share freely, never taking more than you give. *********************************************************************** This file contains the so-called OO #1 API wrapper for the sqlite3 WASM build. It requires that sqlite3-api-glue.js has already run and it installs its deliverable as globalThis.sqlite3.oo1. */ globalThis.sqlite3ApiBootstrap.initializers.push(function(sqlite3){ const toss = (...args)=>{throw new Error(args.join(' '))}; const toss3 = (...args)=>{throw new sqlite3.SQLite3Error(...args)}; const capi = sqlite3.capi, wasm = sqlite3.wasm, util = sqlite3.util; /* What follows is colloquially known as "OO API #1". It is a binding of the sqlite3 API which is designed to be run within the same thread (main or worker) as the one in which the sqlite3 WASM binding was initialized. This wrapper cannot use the sqlite3 binding if, e.g., the wrapper is in the main thread and the sqlite3 API is in a worker. */ /** In order to keep clients from manipulating, perhaps inadvertently, the underlying pointer values of DB and Stmt instances, we'll gate access to them via the `pointer` property accessor and store their real values in this map. Keys = DB/Stmt objects, values = pointer values. This also unifies how those are accessed, for potential use downstream via custom wasm.xWrap() function signatures which know how to extract it. */ const __ptrMap = new WeakMap(); /** Map of DB instances to objects, each object being a map of Stmt wasm pointers to Stmt objects. */ const __stmtMap = new WeakMap(); /** If object opts has _its own_ property named p then that property's value is returned, else dflt is returned. */ const getOwnOption = (opts, p, dflt)=>{ const d = Object.getOwnPropertyDescriptor(opts,p); return d ? d.value : dflt; }; // Documented in DB.checkRc() const checkSqlite3Rc = function(dbPtr, sqliteResultCode){ if(sqliteResultCode){ if(dbPtr instanceof DB) dbPtr = dbPtr.pointer; toss3( "sqlite3 result code",sqliteResultCode+":", (dbPtr ? capi.sqlite3_errmsg(dbPtr) : capi.sqlite3_errstr(sqliteResultCode)) ); } return arguments[0]; }; /** sqlite3_trace_v2() callback which gets installed by the DB ctor if its open-flags contain "t". */ const __dbTraceToConsole = wasm.installFunction('i(ippp)', function(t,c,p,x){ if(capi.SQLITE_TRACE_STMT===t){ // x == SQL, p == sqlite3_stmt* console.log("SQL TRACE #"+(++this.counter)+' via sqlite3@'+c+':', wasm.cstrToJs(x)); } }.bind({counter: 0})); /** A map of sqlite3_vfs pointers to SQL code or a callback function to run when the DB constructor opens a database with the given VFS. In the latter case, the call signature is (theDbObject,sqlite3Namespace) and the callback is expected to throw on error. */ const __vfsPostOpenSql = Object.create(null); /** A proxy for DB class constructors. It must be called with the being-construct DB object as its "this". See the DB constructor for the argument docs. This is split into a separate function in order to enable simple creation of special-case DB constructors, e.g. JsStorageDb and OpfsDb. Expects to be passed a configuration object with the following properties: - `.filename`: the db filename. It may be a special name like ":memory:" or "". - `.flags`: as documented in the DB constructor. - `.vfs`: as documented in the DB constructor. It also accepts those as the first 3 arguments. */ const dbCtorHelper = function ctor(...args){ if(!ctor._name2vfs){ /** Map special filenames which we handle here (instead of in C) to some helpful metadata... As of 2022-09-20, the C API supports the names :localStorage: and :sessionStorage: for kvvfs. However, C code cannot determine (without embedded JS code, e.g. via Emscripten's EM_JS()) whether the kvvfs is legal in the current browser context (namely the main UI thread). In order to help client code fail early on, instead of it being delayed until they try to read or write a kvvfs-backed db, we'll check for those names here and throw if they're not legal in the current context. */ ctor._name2vfs = Object.create(null); const isWorkerThread = ('function'===typeof importScripts/*===running in worker thread*/) ? (n)=>toss3("The VFS for",n,"is only available in the main window thread.") : false; ctor._name2vfs[':localStorage:'] = { vfs: 'kvvfs', filename: isWorkerThread || (()=>'local') }; ctor._name2vfs[':sessionStorage:'] = { vfs: 'kvvfs', filename: isWorkerThread || (()=>'session') }; } const opt = ctor.normalizeArgs(...args); let fn = opt.filename, vfsName = opt.vfs, flagsStr = opt.flags; if(('string'!==typeof fn && 'number'!==typeof fn) || 'string'!==typeof flagsStr || (vfsName && ('string'!==typeof vfsName && 'number'!==typeof vfsName))){ sqlite3.config.error("Invalid DB ctor args",opt,arguments); toss3("Invalid arguments for DB constructor."); } let fnJs = ('number'===typeof fn) ? wasm.cstrToJs(fn) : fn; const vfsCheck = ctor._name2vfs[fnJs]; if(vfsCheck){ vfsName = vfsCheck.vfs; fn = fnJs = vfsCheck.filename(fnJs); } let pDb, oflags = 0; if( flagsStr.indexOf('c')>=0 ){ oflags |= capi.SQLITE_OPEN_CREATE | capi.SQLITE_OPEN_READWRITE; } if( flagsStr.indexOf('w')>=0 ) oflags |= capi.SQLITE_OPEN_READWRITE; if( 0===oflags ) oflags |= capi.SQLITE_OPEN_READONLY; oflags |= capi.SQLITE_OPEN_EXRESCODE; const stack = wasm.pstack.pointer; try { const pPtr = wasm.pstack.allocPtr() /* output (sqlite3**) arg */; let rc = capi.sqlite3_open_v2(fn, pPtr, oflags, vfsName || 0); pDb = wasm.peekPtr(pPtr); checkSqlite3Rc(pDb, rc); capi.sqlite3_extended_result_codes(pDb, 1); if(flagsStr.indexOf('t')>=0){ capi.sqlite3_trace_v2(pDb, capi.SQLITE_TRACE_STMT, __dbTraceToConsole, pDb); } }catch( e ){ if( pDb ) capi.sqlite3_close_v2(pDb); throw e; }finally{ wasm.pstack.restore(stack); } this.filename = fnJs; __ptrMap.set(this, pDb); __stmtMap.set(this, Object.create(null)); try{ // Check for per-VFS post-open SQL/callback... const pVfs = capi.sqlite3_js_db_vfs(pDb); if(!pVfs) toss3("Internal error: cannot get VFS for new db handle."); const postInitSql = __vfsPostOpenSql[pVfs]; if(postInitSql instanceof Function){ postInitSql(this, sqlite3); }else if(postInitSql){ checkSqlite3Rc( pDb, capi.sqlite3_exec(pDb, postInitSql, 0, 0, 0) ); } }catch(e){ this.close(); throw e; } }; /** Sets SQL which should be exec()'d on a DB instance after it is opened with the given VFS pointer. The SQL may be any type supported by the "string:flexible" function argument conversion. Alternately, the 2nd argument may be a function, in which case it is called with (theOo1DbObject,sqlite3Namespace) at the end of the DB() constructor. The function must throw on error, in which case the db is closed and the exception is propagated. This function is intended only for use by DB subclasses or sqlite3_vfs implementations. */ dbCtorHelper.setVfsPostOpenSql = function(pVfs, sql){ __vfsPostOpenSql[pVfs] = sql; }; /** A helper for DB constructors. It accepts either a single config-style object or up to 3 arguments (filename, dbOpenFlags, dbVfsName). It returns a new object containing: { filename: ..., flags: ..., vfs: ... } If passed an object, any additional properties it has are copied as-is into the new object. */ dbCtorHelper.normalizeArgs = function(filename=':memory:',flags = 'c',vfs = null){ const arg = {}; if(1===arguments.length && arguments[0] && 'object'===typeof arguments[0]){ Object.assign(arg, arguments[0]); if(undefined===arg.flags) arg.flags = 'c'; if(undefined===arg.vfs) arg.vfs = null; if(undefined===arg.filename) arg.filename = ':memory:'; }else{ arg.filename = filename; arg.flags = flags; arg.vfs = vfs; } return arg; }; /** The DB class provides a high-level OO wrapper around an sqlite3 db handle. The given db filename must be resolvable using whatever filesystem layer (virtual or otherwise) is set up for the default sqlite3 VFS. Note that the special sqlite3 db names ":memory:" and "" (temporary db) have their normal special meanings here and need not resolve to real filenames, but "" uses an on-storage temporary database and requires that the VFS support that. The second argument specifies the open/create mode for the database. It must be string containing a sequence of letters (in any order, but case sensitive) specifying the mode: - "c": create if it does not exist, else fail if it does not exist. Implies the "w" flag. - "w": write. Implies "r": a db cannot be write-only. - "r": read-only if neither "w" nor "c" are provided, else it is ignored. - "t": enable tracing of SQL executed on this database handle, sending it to `console.log()`. To disable it later, call `sqlite3.capi.sqlite3_trace_v2(thisDb.pointer, 0, 0, 0)`. If "w" is not provided, the db is implicitly read-only, noting that "rc" is meaningless Any other letters are currently ignored. The default is "c". These modes are ignored for the special ":memory:" and "" names and _may_ be ignored altogether for certain VFSes. The final argument is analogous to the final argument of sqlite3_open_v2(): the name of an sqlite3 VFS. Pass a falsy value, or none at all, to use the default. If passed a value, it must be the string name of a VFS. The constructor optionally (and preferably) takes its arguments in the form of a single configuration object with the following properties: - `filename`: database file name - `flags`: open-mode flags - `vfs`: the VFS fname The `filename` and `vfs` arguments may be either JS strings or C-strings allocated via WASM. `flags` is required to be a JS string (because it's specific to this API, which is specific to JS). For purposes of passing a DB instance to C-style sqlite3 functions, the DB object's read-only `pointer` property holds its `sqlite3*` pointer value. That property can also be used to check whether this DB instance is still open. In the main window thread, the filenames `":localStorage:"` and `":sessionStorage:"` are special: they cause the db to use either localStorage or sessionStorage for storing the database using the kvvfs. If one of these names are used, they trump any vfs name set in the arguments. */ const DB = function(...args){ dbCtorHelper.apply(this, args); }; DB.dbCtorHelper = dbCtorHelper; /** Internal-use enum for mapping JS types to DB-bindable types. These do not (and need not) line up with the SQLITE_type values. All values in this enum must be truthy and distinct but they need not be numbers. */ const BindTypes = { null: 1, number: 2, string: 3, boolean: 4, blob: 5 }; BindTypes['undefined'] == BindTypes.null; if(wasm.bigIntEnabled){ BindTypes.bigint = BindTypes.number; } /** This class wraps sqlite3_stmt. Calling this constructor directly will trigger an exception. Use DB.prepare() to create new instances. For purposes of passing a Stmt instance to C-style sqlite3 functions, its read-only `pointer` property holds its `sqlite3_stmt*` pointer value. Other non-function properties include: - `db`: the DB object which created the statement. - `columnCount`: the number of result columns in the query, or 0 for queries which cannot return results. - `parameterCount`: the number of bindable paramters in the query. */ const Stmt = function(){ if(BindTypes!==arguments[2]){ toss3(capi.SQLITE_MISUSE, "Do not call the Stmt constructor directly. Use DB.prepare()."); } this.db = arguments[0]; __ptrMap.set(this, arguments[1]); this.columnCount = capi.sqlite3_column_count(this.pointer); this.parameterCount = capi.sqlite3_bind_parameter_count(this.pointer); }; /** Throws if the given DB has been closed, else it is returned. */ const affirmDbOpen = function(db){ if(!db.pointer) toss3("DB has been closed."); return db; }; /** Throws if ndx is not an integer or if it is out of range for stmt.columnCount, else returns stmt. Reminder: this will also fail after the statement is finalized but the resulting error will be about an out-of-bounds column index rather than a statement-is-finalized error. */ const affirmColIndex = function(stmt,ndx){ if((ndx !== (ndx|0)) || ndx<0 || ndx>=stmt.columnCount){ toss3("Column index",ndx,"is out of range."); } return stmt; }; /** Expects to be passed the `arguments` object from DB.exec(). Does the argument processing/validation, throws on error, and returns a new object on success: { sql: the SQL, opt: optionsObj, cbArg: function} The opt object is a normalized copy of any passed to this function. The sql will be converted to a string if it is provided in one of the supported non-string formats. cbArg is only set if the opt.callback or opt.resultRows are set, in which case it's a function which expects to be passed the current Stmt and returns the callback argument of the type indicated by the input arguments. */ const parseExecArgs = function(db, args){ const out = Object.create(null); out.opt = Object.create(null); switch(args.length){ case 1: if('string'===typeof args[0] || util.isSQLableTypedArray(args[0])){ out.sql = args[0]; }else if(Array.isArray(args[0])){ out.sql = args[0]; }else if(args[0] && 'object'===typeof args[0]){ out.opt = args[0]; out.sql = out.opt.sql; } break; case 2: out.sql = args[0]; out.opt = args[1]; break; default: toss3("Invalid argument count for exec()."); }; out.sql = util.flexibleString(out.sql); if('string'!==typeof out.sql){ toss3("Missing SQL argument or unsupported SQL value type."); } const opt = out.opt; switch(opt.returnValue){ case 'resultRows': if(!opt.resultRows) opt.resultRows = []; out.returnVal = ()=>opt.resultRows; break; case 'saveSql': if(!opt.saveSql) opt.saveSql = []; out.returnVal = ()=>opt.saveSql; break; case undefined: case 'this': out.returnVal = ()=>db; break; default: toss3("Invalid returnValue value:",opt.returnValue); } if(!opt.callback && !opt.returnValue && undefined!==opt.rowMode){ if(!opt.resultRows) opt.resultRows = []; out.returnVal = ()=>opt.resultRows; } if(opt.callback || opt.resultRows){ switch((undefined===opt.rowMode) ? 'array' : opt.rowMode) { case 'object': out.cbArg = (stmt)=>stmt.get(Object.create(null)); break; case 'array': out.cbArg = (stmt)=>stmt.get([]); break; case 'stmt': if(Array.isArray(opt.resultRows)){ toss3("exec(): invalid rowMode for a resultRows array: must", "be one of 'array', 'object',", "a result column number, or column name reference."); } out.cbArg = (stmt)=>stmt; break; default: if(util.isInt32(opt.rowMode)){ out.cbArg = (stmt)=>stmt.get(opt.rowMode); break; }else if('string'===typeof opt.rowMode && opt.rowMode.length>1 && '$'===opt.rowMode[0]){ /* "$X": fetch column named "X" (case-sensitive!). Prior to 2022-12-14 ":X" and "@X" were also permitted, but having so many options is unnecessary and likely to cause confusion. */ const $colName = opt.rowMode.substr(1); out.cbArg = (stmt)=>{ const rc = stmt.get(Object.create(null))[$colName]; return (undefined===rc) ? toss3(capi.SQLITE_NOTFOUND, "exec(): unknown result column:",$colName) : rc; }; break; } toss3("Invalid rowMode:",opt.rowMode); } } return out; }; /** Internal impl of the DB.selectValue(), selectArray(), and selectObject() methods. */ const __selectFirstRow = (db, sql, bind, ...getArgs)=>{ const stmt = db.prepare(sql); try { return stmt.bind(bind).step() ? stmt.get(...getArgs) : undefined; }finally{ stmt.finalize(); } }; /** Internal impl of the DB.selectArrays() and selectObjects() methods. */ const __selectAll = (db, sql, bind, rowMode)=>db.exec({ sql, bind, rowMode, returnValue: 'resultRows' }); /** Expects to be given a DB instance or an `sqlite3*` pointer (may be null) and an sqlite3 API result code. If the result code is not falsy, this function throws an SQLite3Error with an error message from sqlite3_errmsg(), using db (or, if db is-a DB, db.pointer) as the db handle, or sqlite3_errstr() if db is falsy. Note that if it's passed a non-error code like SQLITE_ROW or SQLITE_DONE, it will still throw but the error string might be "Not an error." The various non-0 non-error codes need to be checked for in client code where they are expected. If it does not throw, it returns its first argument. */ DB.checkRc = (db,resultCode)=>checkSqlite3Rc(db,resultCode); DB.prototype = { /** Returns true if this db handle is open, else false. */ isOpen: function(){ return !!this.pointer; }, /** Throws if this given DB has been closed, else returns `this`. */ affirmOpen: function(){ return affirmDbOpen(this); }, /** Finalizes all open statements and closes this database connection. This is a no-op if the db has already been closed. After calling close(), `this.pointer` will resolve to `undefined`, so that can be used to check whether the db instance is still opened. If this.onclose.before is a function then it is called before any close-related cleanup. If this.onclose.after is a function then it is called after the db is closed but before auxiliary state like this.filename is cleared. Both onclose handlers are passed this object, with the onclose object as their "this," noting that the db will have been closed when onclose.after is called. If this db is not opened when close() is called, neither of the handlers are called. Any exceptions the handlers throw are ignored because "destructors must not throw." Note that garbage collection of a db handle, if it happens at all, will never trigger close(), so onclose handlers are not a reliable way to implement close-time cleanup or maintenance of a db. */ close: function(){ if(this.pointer){ if(this.onclose && (this.onclose.before instanceof Function)){ try{this.onclose.before(this)} catch(e){/*ignore*/} } const pDb = this.pointer; Object.keys(__stmtMap.get(this)).forEach((k,s)=>{ if(s && s.pointer) s.finalize(); }); __ptrMap.delete(this); __stmtMap.delete(this); capi.sqlite3_close_v2(pDb); if(this.onclose && (this.onclose.after instanceof Function)){ try{this.onclose.after(this)} catch(e){/*ignore*/} } delete this.filename; } }, /** Returns the number of changes, as per sqlite3_changes() (if the first argument is false) or sqlite3_total_changes() (if it's true). If the 2nd argument is true, it uses sqlite3_changes64() or sqlite3_total_changes64(), which will trigger an exception if this build does not have BigInt support enabled. */ changes: function(total=false,sixtyFour=false){ const p = affirmDbOpen(this).pointer; if(total){ return sixtyFour ? capi.sqlite3_total_changes64(p) : capi.sqlite3_total_changes(p); }else{ return sixtyFour ? capi.sqlite3_changes64(p) : capi.sqlite3_changes(p); } }, /** Similar to the this.filename but returns the sqlite3_db_filename() value for the given database name, defaulting to "main". The argument may be either a JS string or a pointer to a WASM-allocated C-string. */ dbFilename: function(dbName='main'){ return capi.sqlite3_db_filename(affirmDbOpen(this).pointer, dbName); }, /** Returns the name of the given 0-based db number, as documented for sqlite3_db_name(). */ dbName: function(dbNumber=0){ return capi.sqlite3_db_name(affirmDbOpen(this).pointer, dbNumber); }, /** Returns the name of the sqlite3_vfs used by the given database of this connection (defaulting to 'main'). The argument may be either a JS string or a WASM C-string. Returns undefined if the given db name is invalid. Throws if this object has been close()d. */ dbVfsName: function(dbName=0){ let rc; const pVfs = capi.sqlite3_js_db_vfs( affirmDbOpen(this).pointer, dbName ); if(pVfs){ const v = new capi.sqlite3_vfs(pVfs); try{ rc = wasm.cstrToJs(v.$zName) } finally { v.dispose() } } return rc; }, /** Compiles the given SQL and returns a prepared Stmt. This is the only way to create new Stmt objects. Throws on error. The given SQL must be a string, a Uint8Array holding SQL, a WASM pointer to memory holding the NUL-terminated SQL string, or an array of strings. In the latter case, the array is concatenated together, with no separators, to form the SQL string (arrays are often a convenient way to formulate long statements). If the SQL contains no statements, an SQLite3Error is thrown. Design note: the C API permits empty SQL, reporting it as a 0 result code and a NULL stmt pointer. Supporting that case here would cause extra work for all clients: any use of the Stmt API on such a statement will necessarily throw, so clients would be required to check `stmt.pointer` after calling `prepare()` in order to determine whether the Stmt instance is empty or not. Long-time practice (with other sqlite3 script bindings) suggests that the empty-prepare case is sufficiently rare that supporting it here would simply hurt overall usability. */ prepare: function(sql){ affirmDbOpen(this); const stack = wasm.pstack.pointer; let ppStmt, pStmt; try{ ppStmt = wasm.pstack.alloc(8)/* output (sqlite3_stmt**) arg */; DB.checkRc(this, capi.sqlite3_prepare_v2(this.pointer, sql, -1, ppStmt, null)); pStmt = wasm.peekPtr(ppStmt); } finally { wasm.pstack.restore(stack); } if(!pStmt) toss3("Cannot prepare empty SQL."); const stmt = new Stmt(this, pStmt, BindTypes); __stmtMap.get(this)[pStmt] = stmt; return stmt; }, /** Executes one or more SQL statements in the form of a single string. Its arguments must be either (sql,optionsObject) or (optionsObject). In the latter case, optionsObject.sql must contain the SQL to execute. By default it returns this object but that can be changed via the `returnValue` option as described below. Throws on error. If no SQL is provided, or a non-string is provided, an exception is triggered. Empty SQL, on the other hand, is simply a no-op. The optional options object may contain any of the following properties: - `sql` = the SQL to run (unless it's provided as the first argument). This must be of type string, Uint8Array, or an array of strings. In the latter case they're concatenated together as-is, _with no separator_ between elements, before evaluation. The array form is often simpler for long hand-written queries. - `bind` = a single value valid as an argument for Stmt.bind(). This is _only_ applied to the _first_ non-empty statement in the SQL which has any bindable parameters. (Empty statements are skipped entirely.) - `saveSql` = an optional array. If set, the SQL of each executed statement is appended to this array before the statement is executed (but after it is prepared - we don't have the string until after that). Empty SQL statements are elided but can have odd effects in the output. e.g. SQL of: `"select 1; -- empty\n; select 2"` will result in an array containing `["select 1;", "--empty \n; select 2"]`. That's simply how sqlite3 records the SQL for the 2nd statement. ================================================================== The following options apply _only_ to the _first_ statement which has a non-zero result column count, regardless of whether the statement actually produces any result rows. ================================================================== - `columnNames`: if this is an array, the column names of the result set are stored in this array before the callback (if any) is triggered (regardless of whether the query produces any result rows). If no statement has result columns, this value is unchanged. Achtung: an SQL result may have multiple columns with identical names. - `callback` = a function which gets called for each row of the result set, but only if that statement has any result _rows_. The callback's "this" is the options object, noting that this function synthesizes one if the caller does not pass one to exec(). The second argument passed to the callback is always the current Stmt object, as it's needed if the caller wants to fetch the column names or some such (noting that they could also be fetched via `this.columnNames`, if the client provides the `columnNames` option). If the callback returns a literal `false` (as opposed to any other falsy value, e.g. an implicit `undefined` return), any ongoing statement-`step()` iteration stops without an error. The return value of the callback is otherwise ignored. ACHTUNG: The callback MUST NOT modify the Stmt object. Calling any of the Stmt.get() variants, Stmt.getColumnName(), or similar, is legal, but calling step() or finalize() is not. Member methods which are illegal in this context will trigger an exception, but clients must also refrain from using any lower-level (C-style) APIs which might modify the statement. The first argument passed to the callback defaults to an array of values from the current result row but may be changed with ... - `rowMode` = specifies the type of he callback's first argument. It may be any of... A) A string describing what type of argument should be passed as the first argument to the callback: A.1) `'array'` (the default) causes the results of `stmt.get([])` to be passed to the `callback` and/or appended to `resultRows` A.2) `'object'` causes the results of `stmt.get(Object.create(null))` to be passed to the `callback` and/or appended to `resultRows`. Achtung: an SQL result may have multiple columns with identical names. In that case, the right-most column will be the one set in this object! A.3) `'stmt'` causes the current Stmt to be passed to the callback, but this mode will trigger an exception if `resultRows` is an array because appending the statement to the array would be downright unhelpful. B) An integer, indicating a zero-based column in the result row. Only that one single value will be passed on. C) A string with a minimum length of 2 and leading character of '$' will fetch the row as an object, extract that one field, and pass that field's value to the callback. Note that these keys are case-sensitive so must match the case used in the SQL. e.g. `"select a A from t"` with a `rowMode` of `'$A'` would work but `'$a'` would not. A reference to a column not in the result set will trigger an exception on the first row (as the check is not performed until rows are fetched). Note also that `$` is a legal identifier character in JS so need not be quoted. Any other `rowMode` value triggers an exception. - `resultRows`: if this is an array, it functions similarly to the `callback` option: each row of the result set (if any), with the exception that the `rowMode` 'stmt' is not legal. It is legal to use both `resultRows` and `callback`, but `resultRows` is likely much simpler to use for small data sets and can be used over a WebWorker-style message interface. exec() throws if `resultRows` is set and `rowMode` is 'stmt'. - `returnValue`: is a string specifying what this function should return: A) The default value is (usually) `"this"`, meaning that the DB object itself should be returned. The exceptions is if the caller passes neither of `callback` nor `returnValue` but does pass an explicit `rowMode` then the default `returnValue` is `"resultRows"`, described below. B) `"resultRows"` means to return the value of the `resultRows` option. If `resultRows` is not set, this function behaves as if it were set to an empty array. C) `"saveSql"` means to return the value of the `saveSql` option. If `saveSql` is not set, this function behaves as if it were set to an empty array. Potential TODOs: - `bind`: permit an array of arrays/objects to bind. The first sub-array would act on the first statement which has bindable parameters (as it does now). The 2nd would act on the next such statement, etc. - `callback` and `resultRows`: permit an array entries with semantics similar to those described for `bind` above. */ exec: function(/*(sql [,obj]) || (obj)*/){ affirmDbOpen(this); const arg = parseExecArgs(this, arguments); if(!arg.sql){ return toss3("exec() requires an SQL string."); } const opt = arg.opt; const callback = opt.callback; const resultRows = Array.isArray(opt.resultRows) ? opt.resultRows : undefined; let stmt; let bind = opt.bind; let evalFirstResult = !!( arg.cbArg || opt.columnNames || resultRows ) /* true to step through the first result-returning statement */; const stack = wasm.scopedAllocPush(); const saveSql = Array.isArray(opt.saveSql) ? opt.saveSql : undefined; try{ const isTA = util.isSQLableTypedArray(arg.sql) /* Optimization: if the SQL is a TypedArray we can save some string conversion costs. */; /* Allocate the two output pointers (ppStmt, pzTail) and heap space for the SQL (pSql). When prepare_v2() returns, pzTail will point to somewhere in pSql. */ let sqlByteLen = isTA ? arg.sql.byteLength : wasm.jstrlen(arg.sql); const ppStmt = wasm.scopedAlloc( /* output (sqlite3_stmt**) arg and pzTail */ (2 * wasm.ptrSizeof) + (sqlByteLen + 1/* SQL + NUL */) ); const pzTail = ppStmt + wasm.ptrSizeof /* final arg to sqlite3_prepare_v2() */; let pSql = pzTail + wasm.ptrSizeof; const pSqlEnd = pSql + sqlByteLen; if(isTA) wasm.heap8().set(arg.sql, pSql); else wasm.jstrcpy(arg.sql, wasm.heap8(), pSql, sqlByteLen, false); wasm.poke(pSql + sqlByteLen, 0/*NUL terminator*/); while(pSql && wasm.peek(pSql, 'i8') /* Maintenance reminder:^^^ _must_ be 'i8' or else we will very likely cause an endless loop. What that's doing is checking for a terminating NUL byte. If we use i32 or similar then we read 4 bytes, read stuff around the NUL terminator, and get stuck in and endless loop at the end of the SQL, endlessly re-preparing an empty statement. */ ){ wasm.pokePtr([ppStmt, pzTail], 0); DB.checkRc(this, capi.sqlite3_prepare_v3( this.pointer, pSql, sqlByteLen, 0, ppStmt, pzTail )); const pStmt = wasm.peekPtr(ppStmt); pSql = wasm.peekPtr(pzTail); sqlByteLen = pSqlEnd - pSql; if(!pStmt) continue; if(saveSql) saveSql.push(capi.sqlite3_sql(pStmt).trim()); stmt = new Stmt(this, pStmt, BindTypes); if(bind && stmt.parameterCount){ stmt.bind(bind); bind = null; } if(evalFirstResult && stmt.columnCount){ /* Only forward SELECT results for the FIRST query in the SQL which potentially has them. */ evalFirstResult = false; if(Array.isArray(opt.columnNames)){ stmt.getColumnNames(opt.columnNames); } if(arg.cbArg || resultRows){ for(; stmt.step(); stmt._isLocked = false){ stmt._isLocked = true; const row = arg.cbArg(stmt); if(resultRows) resultRows.push(row); if(callback && false === callback.call(opt, row, stmt)){ break; } } stmt._isLocked = false; } }else{ stmt.step(); } stmt.finalize(); stmt = null; } }/*catch(e){ sqlite3.config.warn("DB.exec() is propagating exception",opt,e); throw e; }*/finally{ if(stmt){ delete stmt._isLocked; stmt.finalize(); } wasm.scopedAllocPop(stack); } return arg.returnVal(); }/*exec()*/, /** Creates a new UDF (User-Defined Function) which is accessible via SQL code. This function may be called in any of the following forms: - (name, function) - (name, function, optionsObject) - (name, optionsObject) - (optionsObject) In the final two cases, the function must be defined as the `callback` property of the options object (optionally called `xFunc` to align with the C API documentation). In the final case, the function's name must be the 'name' property. The first two call forms can only be used for creating scalar functions. Creating an aggregate or window function requires the options-object form (see below for details). UDFs can be removed as documented for sqlite3_create_function_v2() and sqlite3_create_window_function(), but doing so will "leak" the JS-created WASM binding of those functions (meaning that their entries in the WASM indirect function table still exist). Eliminating that potential leak is a pending TODO. On success, returns this object. Throws on error. When called from SQL arguments to the UDF, and its result, will be converted between JS and SQL with as much fidelity as is feasible, triggering an exception if a type conversion cannot be determined. The docs for sqlite3_create_function_v2() describe the conversions in more detail. The values set in the options object differ for scalar and aggregate functions: - Scalar: set the `xFunc` function-type property to the UDF function. - Aggregate: set the `xStep` and `xFinal` function-type properties to the "step" and "final" callbacks for the aggregate. Do not set the `xFunc` property. - Window: set the `xStep`, `xFinal`, `xValue`, and `xInverse` function-type properties. Do not set the `xFunc` property. The options object may optionally have an `xDestroy` function-type property, as per sqlite3_create_function_v2(). Its argument will be the WASM-pointer-type value of the `pApp` property, and this function will throw if `pApp` is defined but is not null, undefined, or a numeric (WASM pointer) value. i.e. `pApp`, if set, must be value suitable for use as a WASM pointer argument, noting that `null` or `undefined` will translate to 0 for that purpose. The options object may contain flags to modify how the function is defined: - `arity`: the number of arguments which SQL calls to this function expect or require. The default value is `xFunc.length` or `xStep.length` (i.e. the number of declared parameters it has) **MINUS 1** (see below for why). As a special case, if the `length` is 0, its arity is also 0 instead of -1. A negative arity value means that the function is variadic and may accept any number of arguments, up to sqlite3's compile-time limits. sqlite3 will enforce the argument count if is zero or greater. The callback always receives a pointer to an `sqlite3_context` object as its first argument. Any arguments after that are from SQL code. The leading context argument does _not_ count towards the function's arity. See the docs for sqlite3.capi.sqlite3_create_function_v2() for why that argument is needed in the interface. The following options-object properties correspond to flags documented at: https://sqlite.org/c3ref/create_function.html - `deterministic` = sqlite3.capi.SQLITE_DETERMINISTIC - `directOnly` = sqlite3.capi.SQLITE_DIRECTONLY - `innocuous` = sqlite3.capi.SQLITE_INNOCUOUS Sidebar: the ability to add new WASM-accessible functions to the runtime requires that the WASM build is compiled with the equivalent functionality as that provided by Emscripten's `-sALLOW_TABLE_GROWTH` flag. */ createFunction: function f(name, xFunc, opt){ const isFunc = (f)=>(f instanceof Function); switch(arguments.length){ case 1: /* (optionsObject) */ opt = name; name = opt.name; xFunc = opt.xFunc || 0; break; case 2: /* (name, callback|optionsObject) */ if(!isFunc(xFunc)){ opt = xFunc; xFunc = opt.xFunc || 0; } break; case 3: /* name, xFunc, opt */ break; default: break; } if(!opt) opt = {}; if('string' !== typeof name){ toss3("Invalid arguments: missing function name."); } let xStep = opt.xStep || 0; let xFinal = opt.xFinal || 0; const xValue = opt.xValue || 0; const xInverse = opt.xInverse || 0; let isWindow = undefined; if(isFunc(xFunc)){ isWindow = false; if(isFunc(xStep) || isFunc(xFinal)){ toss3("Ambiguous arguments: scalar or aggregate?"); } xStep = xFinal = null; }else if(isFunc(xStep)){ if(!isFunc(xFinal)){ toss3("Missing xFinal() callback for aggregate or window UDF."); } xFunc = null; }else if(isFunc(xFinal)){ toss3("Missing xStep() callback for aggregate or window UDF."); }else{ toss3("Missing function-type properties."); } if(false === isWindow){ if(isFunc(xValue) || isFunc(xInverse)){ toss3("xValue and xInverse are not permitted for non-window UDFs."); } }else if(isFunc(xValue)){ if(!isFunc(xInverse)){ toss3("xInverse must be provided if xValue is."); } isWindow = true; }else if(isFunc(xInverse)){ toss3("xValue must be provided if xInverse is."); } const pApp = opt.pApp; if(undefined!==pApp && null!==pApp && (('number'!==typeof pApp) || !util.isInt32(pApp))){ toss3("Invalid value for pApp property. Must be a legal WASM pointer value."); } const xDestroy = opt.xDestroy || 0; if(xDestroy && !isFunc(xDestroy)){ toss3("xDestroy property must be a function."); } let fFlags = 0 /*flags for sqlite3_create_function_v2()*/; if(getOwnOption(opt, 'deterministic')) fFlags |= capi.SQLITE_DETERMINISTIC; if(getOwnOption(opt, 'directOnly')) fFlags |= capi.SQLITE_DIRECTONLY; if(getOwnOption(opt, 'innocuous')) fFlags |= capi.SQLITE_INNOCUOUS; name = name.toLowerCase(); const xArity = xFunc || xStep; const arity = getOwnOption(opt, 'arity'); const arityArg = ('number'===typeof arity ? arity : (xArity.length ? xArity.length-1/*for pCtx arg*/ : 0)); let rc; if( isWindow ){ rc = capi.sqlite3_create_window_function( this.pointer, name, arityArg, capi.SQLITE_UTF8 | fFlags, pApp || 0, xStep, xFinal, xValue, xInverse, xDestroy); }else{ rc = capi.sqlite3_create_function_v2( this.pointer, name, arityArg, capi.SQLITE_UTF8 | fFlags, pApp || 0, xFunc, xStep, xFinal, xDestroy); } DB.checkRc(this, rc); return this; }/*createFunction()*/, /** Prepares the given SQL, step()s it one time, and returns the value of the first result column. If it has no results, undefined is returned. If passed a second argument, it is treated like an argument to Stmt.bind(), so may be any type supported by that function. Passing the undefined value is the same as passing no value, which is useful when... If passed a 3rd argument, it is expected to be one of the SQLITE_{typename} constants. Passing the undefined value is the same as not passing a value. Throws on error (e.g. malformed SQL). */ selectValue: function(sql,bind,asType){ return __selectFirstRow(this, sql, bind, 0, asType); }, /** Runs the given query and returns an array of the values from the first result column of each row of the result set. The 2nd argument is an optional value for use in a single-argument call to Stmt.bind(). The 3rd argument may be any value suitable for use as the 2nd argument to Stmt.get(). If a 3rd argument is desired but no bind data are needed, pass `undefined` for the 2nd argument. If there are no result rows, an empty array is returned. */ selectValues: function(sql,bind,asType){ const stmt = this.prepare(sql), rc = []; try { stmt.bind(bind); while(stmt.step()) rc.push(stmt.get(0,asType)); }finally{ stmt.finalize(); } return rc; }, /** Prepares the given SQL, step()s it one time, and returns an array containing the values of the first result row. If it has no results, `undefined` is returned. If passed a second argument other than `undefined`, it is treated like an argument to Stmt.bind(), so may be any type supported by that function. Throws on error (e.g. malformed SQL). */ selectArray: function(sql,bind){ return __selectFirstRow(this, sql, bind, []); }, /** Prepares the given SQL, step()s it one time, and returns an object containing the key/value pairs of the first result row. If it has no results, `undefined` is returned. Note that the order of returned object's keys is not guaranteed to be the same as the order of the fields in the query string. If passed a second argument other than `undefined`, it is treated like an argument to Stmt.bind(), so may be any type supported by that function. Throws on error (e.g. malformed SQL). */ selectObject: function(sql,bind){ return __selectFirstRow(this, sql, bind, {}); }, /** Runs the given SQL and returns an array of all results, with each row represented as an array, as per the 'array' `rowMode` option to `exec()`. An empty result set resolves to an empty array. The second argument, if any, is treated as the 'bind' option to a call to exec(). */ selectArrays: function(sql,bind){ return __selectAll(this, sql, bind, 'array'); }, /** Works identically to selectArrays() except that each value in the returned array is an object, as per the 'object' `rowMode` option to `exec()`. */ selectObjects: function(sql,bind){ return __selectAll(this, sql, bind, 'object'); }, /** Returns the number of currently-opened Stmt handles for this db handle, or 0 if this DB instance is closed. Note that only handles prepared via this.prepare() are counted, and not handles prepared using capi.sqlite3_prepare_v3() (or equivalent). */ openStatementCount: function(){ return this.pointer ? Object.keys(__stmtMap.get(this)).length : 0; }, /** Starts a transaction, calls the given callback, and then either rolls back or commits the savepoint, depending on whether the callback throws. The callback is passed this db object as its only argument. On success, returns the result of the callback. Throws on error. Note that transactions may not be nested, so this will throw if it is called recursively. For nested transactions, use the savepoint() method or manually manage SAVEPOINTs using exec(). If called with 2 arguments, the first must be a keyword which is legal immediately after a BEGIN statement, e.g. one of "DEFERRED", "IMMEDIATE", or "EXCLUSIVE". Though the exact list of supported keywords is not hard-coded here, in order to be future-compatible, if the argument does not look like a single keyword then an exception is triggered with a description of the problem. */ transaction: function(/* [beginQualifier,] */callback){ let opener = 'BEGIN'; if(arguments.length>1){ if(/[^a-zA-Z]/.test(arguments[0])){ toss3(capi.SQLITE_MISUSE, "Invalid argument for BEGIN qualifier."); } opener += ' '+arguments[0]; callback = arguments[1]; } affirmDbOpen(this).exec(opener); try { const rc = callback(this); this.exec("COMMIT"); return rc; }catch(e){ this.exec("ROLLBACK"); throw e; } }, /** This works similarly to transaction() but uses sqlite3's SAVEPOINT feature. This function starts a savepoint (with an unspecified name) and calls the given callback function, passing it this db object. If the callback returns, the savepoint is released (committed). If the callback throws, the savepoint is rolled back. If it does not throw, it returns the result of the callback. */ savepoint: function(callback){ affirmDbOpen(this).exec("SAVEPOINT oo1"); try { const rc = callback(this); this.exec("RELEASE oo1"); return rc; }catch(e){ this.exec("ROLLBACK to SAVEPOINT oo1; RELEASE SAVEPOINT oo1"); throw e; } }, /** A convenience form of DB.checkRc(this,resultCode). If it does not throw, it returns this object. */ checkRc: function(resultCode){ return DB.checkRc(this, resultCode); } }/*DB.prototype*/; /** Throws if the given Stmt has been finalized, else stmt is returned. */ const affirmStmtOpen = function(stmt){ if(!stmt.pointer) toss3("Stmt has been closed."); return stmt; }; /** Returns an opaque truthy value from the BindTypes enum if v's type is a valid bindable type, else returns a falsy value. As a special case, a value of undefined is treated as a bind type of null. */ const isSupportedBindType = function(v){ let t = BindTypes[(null===v||undefined===v) ? 'null' : typeof v]; switch(t){ case BindTypes.boolean: case BindTypes.null: case BindTypes.number: case BindTypes.string: return t; case BindTypes.bigint: if(wasm.bigIntEnabled) return t; /* else fall through */ default: return util.isBindableTypedArray(v) ? BindTypes.blob : undefined; } }; /** If isSupportedBindType(v) returns a truthy value, this function returns that value, else it throws. */ const affirmSupportedBindType = function(v){ //sqlite3.config.log('affirmSupportedBindType',v); return isSupportedBindType(v) || toss3("Unsupported bind() argument type:",typeof v); }; /** If key is a number and within range of stmt's bound parameter count, key is returned. If key is not a number then it is checked against named parameters. If a match is found, its index is returned. Else it throws. */ const affirmParamIndex = function(stmt,key){ const n = ('number'===typeof key) ? key : capi.sqlite3_bind_parameter_index(stmt.pointer, key); if(0===n || !util.isInt32(n)){ toss3("Invalid bind() parameter name: "+key); } else if(n<1 || n>stmt.parameterCount) toss3("Bind index",key,"is out of range."); return n; }; /** If stmt._isLocked is truthy, this throws an exception complaining that the 2nd argument (an operation name, e.g. "bind()") is not legal while the statement is "locked". Locking happens before an exec()-like callback is passed a statement, to ensure that the callback does not mutate or finalize the statement. If it does not throw, it returns stmt. */ const affirmUnlocked = function(stmt,currentOpName){ if(stmt._isLocked){ toss3("Operation is illegal when statement is locked:",currentOpName); } return stmt; }; /** Binds a single bound parameter value on the given stmt at the given index (numeric or named) using the given bindType (see the BindTypes enum) and value. Throws on error. Returns stmt on success. */ const bindOne = function f(stmt,ndx,bindType,val){ affirmUnlocked(affirmStmtOpen(stmt), 'bind()'); if(!f._){ f._tooBigInt = (v)=>toss3( "BigInt value is too big to store without precision loss:", v ); /* Reminder: when not in BigInt mode, it's impossible for JS to represent a number out of the range we can bind, so we have no range checking. */ f._ = { string: function(stmt, ndx, val, asBlob){ const [pStr, n] = wasm.allocCString(val, true); const f = asBlob ? capi.sqlite3_bind_blob : capi.sqlite3_bind_text; return f(stmt.pointer, ndx, pStr, n, capi.SQLITE_WASM_DEALLOC); } }; }/* static init */ affirmSupportedBindType(val); ndx = affirmParamIndex(stmt,ndx); let rc = 0; switch((null===val || undefined===val) ? BindTypes.null : bindType){ case BindTypes.null: rc = capi.sqlite3_bind_null(stmt.pointer, ndx); break; case BindTypes.string: rc = f._.string(stmt, ndx, val, false); break; case BindTypes.number: { let m; if(util.isInt32(val)) m = capi.sqlite3_bind_int; else if('bigint'===typeof val){ if(!util.bigIntFits64(val)){ f._tooBigInt(val); }else if(wasm.bigIntEnabled){ m = capi.sqlite3_bind_int64; }else if(util.bigIntFitsDouble(val)){ val = Number(val); m = capi.sqlite3_bind_double; }else{ f._tooBigInt(val); } }else{ // !int32, !bigint val = Number(val); if(wasm.bigIntEnabled && Number.isInteger(val)){ m = capi.sqlite3_bind_int64; }else{ m = capi.sqlite3_bind_double; } } rc = m(stmt.pointer, ndx, val); break; } case BindTypes.boolean: rc = capi.sqlite3_bind_int(stmt.pointer, ndx, val ? 1 : 0); break; case BindTypes.blob: { if('string'===typeof val){ rc = f._.string(stmt, ndx, val, true); break; }else if(val instanceof ArrayBuffer){ val = new Uint8Array(val); }else if(!util.isBindableTypedArray(val)){ toss3("Binding a value as a blob requires", "that it be a string, Uint8Array, Int8Array, or ArrayBuffer."); } const pBlob = wasm.alloc(val.byteLength || 1); wasm.heap8().set(val.byteLength ? val : [0], pBlob) rc = capi.sqlite3_bind_blob(stmt.pointer, ndx, pBlob, val.byteLength, capi.SQLITE_WASM_DEALLOC); break; } default: sqlite3.config.warn("Unsupported bind() argument type:",val); toss3("Unsupported bind() argument type: "+(typeof val)); } if(rc) DB.checkRc(stmt.db.pointer, rc); stmt._mayGet = false; return stmt; }; Stmt.prototype = { /** "Finalizes" this statement. This is a no-op if the statement has already been finalizes. Returns undefined. Most methods in this class will throw if called after this is. */ finalize: function(){ if(this.pointer){ affirmUnlocked(this,'finalize()'); delete __stmtMap.get(this.db)[this.pointer]; capi.sqlite3_finalize(this.pointer); __ptrMap.delete(this); delete this._mayGet; delete this.columnCount; delete this.parameterCount; delete this.db; delete this._isLocked; } }, /** Clears all bound values. Returns this object. Throws if this statement has been finalized. */ clearBindings: function(){ affirmUnlocked(affirmStmtOpen(this), 'clearBindings()') capi.sqlite3_clear_bindings(this.pointer); this._mayGet = false; return this; }, /** Resets this statement so that it may be step()ed again from the beginning. Returns this object. Throws if this statement has been finalized. If passed a truthy argument then this.clearBindings() is also called, otherwise any existing bindings, along with any memory allocated for them, are retained. */ reset: function(alsoClearBinds){ affirmUnlocked(this,'reset()'); if(alsoClearBinds) this.clearBindings(); capi.sqlite3_reset(affirmStmtOpen(this).pointer); this._mayGet = false; return this; }, /** Binds one or more values to its bindable parameters. It accepts 1 or 2 arguments: If passed a single argument, it must be either an array, an object, or a value of a bindable type (see below). If passed 2 arguments, the first one is the 1-based bind index or bindable parameter name and the second one must be a value of a bindable type. Bindable value types: - null is bound as NULL. - undefined as a standalone value is a no-op intended to simplify certain client-side use cases: passing undefined as a value to this function will not actually bind anything and this function will skip confirmation that binding is even legal. (Those semantics simplify certain client-side uses.) Conversely, a value of undefined as an array or object property when binding an array/object (see below) is treated the same as null. - Numbers are bound as either doubles or integers: doubles if they are larger than 32 bits, else double or int32, depending on whether they have a fractional part. Booleans are bound as integer 0 or 1. It is not expected the distinction of binding doubles which have no fractional parts is integers is significant for the majority of clients due to sqlite3's data typing model. If [BigInt] support is enabled then this routine will bind BigInt values as 64-bit integers if they'll fit in 64 bits. If that support disabled, it will store the BigInt as an int32 or a double if it can do so without loss of precision. If the BigInt is _too BigInt_ then it will throw. - Strings are bound as strings (use bindAsBlob() to force blob binding). - Uint8Array, Int8Array, and ArrayBuffer instances are bound as blobs. If passed an array, each element of the array is bound at the parameter index equal to the array index plus 1 (because arrays are 0-based but binding is 1-based). If passed an object, each object key is treated as a bindable parameter name. The object keys _must_ match any bindable parameter names, including any `$`, `@`, or `:` prefix. Because `$` is a legal identifier chararacter in JavaScript, that is the suggested prefix for bindable parameters: `stmt.bind({$a: 1, $b: 2})`. It returns this object on success and throws on error. Errors include: - Any bind index is out of range, a named bind parameter does not match, or this statement has no bindable parameters. - Any value to bind is of an unsupported type. - Passed no arguments or more than two. - The statement has been finalized. */ bind: function(/*[ndx,] arg*/){ affirmStmtOpen(this); let ndx, arg; switch(arguments.length){ case 1: ndx = 1; arg = arguments[0]; break; case 2: ndx = arguments[0]; arg = arguments[1]; break; default: toss3("Invalid bind() arguments."); } if(undefined===arg){ /* It might seem intuitive to bind undefined as NULL but this approach simplifies certain client-side uses when passing on arguments between 2+ levels of functions. */ return this; }else if(!this.parameterCount){ toss3("This statement has no bindable parameters."); } this._mayGet = false; if(null===arg){ /* bind NULL */ return bindOne(this, ndx, BindTypes.null, arg); } else if(Array.isArray(arg)){ /* bind each entry by index */ if(1!==arguments.length){ toss3("When binding an array, an index argument is not permitted."); } arg.forEach((v,i)=>bindOne(this, i+1, affirmSupportedBindType(v), v)); return this; }else if(arg instanceof ArrayBuffer){ arg = new Uint8Array(arg); } if('object'===typeof arg/*null was checked above*/ && !util.isBindableTypedArray(arg)){ /* Treat each property of arg as a named bound parameter. */ if(1!==arguments.length){ toss3("When binding an object, an index argument is not permitted."); } Object.keys(arg) .forEach(k=>bindOne(this, k, affirmSupportedBindType(arg[k]), arg[k])); return this; }else{ return bindOne(this, ndx, affirmSupportedBindType(arg), arg); } toss3("Should not reach this point."); }, /** Special case of bind() which binds the given value using the BLOB binding mechanism instead of the default selected one for the value. The ndx may be a numbered or named bind index. The value must be of type string, null/undefined (both get treated as null), or a TypedArray of a type supported by the bind() API. This API cannot bind numbers as blobs. If passed a single argument, a bind index of 1 is assumed and the first argument is the value. */ bindAsBlob: function(ndx,arg){ affirmStmtOpen(this); if(1===arguments.length){ arg = ndx; ndx = 1; } const t = affirmSupportedBindType(arg); if(BindTypes.string !== t && BindTypes.blob !== t && BindTypes.null !== t){ toss3("Invalid value type for bindAsBlob()"); } return bindOne(this, ndx, BindTypes.blob, arg); }, /** Steps the statement one time. If the result indicates that a row of data is available, a truthy value is returned. If no row of data is available, a falsy value is returned. Throws on error. */ step: function(){ affirmUnlocked(this, 'step()'); const rc = capi.sqlite3_step(affirmStmtOpen(this).pointer); switch(rc){ case capi.SQLITE_DONE: return this._mayGet = false; case capi.SQLITE_ROW: return this._mayGet = true; default: this._mayGet = false; sqlite3.config.warn("sqlite3_step() rc=",rc, capi.sqlite3_js_rc_str(rc), "SQL =", capi.sqlite3_sql(this.pointer)); DB.checkRc(this.db.pointer, rc); } }, /** Functions exactly like step() except that... 1) On success, it calls this.reset() and returns this object. 2) On error, it throws and does not call reset(). This is intended to simplify constructs like: ``` for(...) { stmt.bind(...).stepReset(); } ``` Note that the reset() call makes it illegal to call this.get() after the step. */ stepReset: function(){ this.step(); return this.reset(); }, /** Functions like step() except that it finalizes this statement immediately after stepping unless the step cannot be performed because the statement is locked. Throws on error, but any error other than the statement-is-locked case will also trigger finalization of this statement. On success, it returns true if the step indicated that a row of data was available, else it returns false. This is intended to simplify use cases such as: ``` aDb.prepare("insert into foo(a) values(?)").bind(123).stepFinalize(); ``` */ stepFinalize: function(){ const rc = this.step(); this.finalize(); return rc; }, /** Fetches the value from the given 0-based column index of the current data row, throwing if index is out of range. Requires that step() has just returned a truthy value, else an exception is thrown. By default it will determine the data type of the result automatically. If passed a second arugment, it must be one of the enumeration values for sqlite3 types, which are defined as members of the sqlite3 module: SQLITE_INTEGER, SQLITE_FLOAT, SQLITE_TEXT, SQLITE_BLOB. Any other value, except for undefined, will trigger an exception. Passing undefined is the same as not passing a value. It is legal to, e.g., fetch an integer value as a string, in which case sqlite3 will convert the value to a string. If ndx is an array, this function behaves a differently: it assigns the indexes of the array, from 0 to the number of result columns, to the values of the corresponding column, and returns that array. If ndx is a plain object, this function behaves even differentlier: it assigns the properties of the object to the values of their corresponding result columns. Blobs are returned as Uint8Array instances. Potential TODO: add type ID SQLITE_JSON, which fetches the result as a string and passes it (if it's not null) to JSON.parse(), returning the result of that. Until then, getJSON() can be used for that. */ get: function(ndx,asType){ if(!affirmStmtOpen(this)._mayGet){ toss3("Stmt.step() has not (recently) returned true."); } if(Array.isArray(ndx)){ let i = 0; while(i=Number.MIN_SAFE_INTEGER && rc<=Number.MAX_SAFE_INTEGER){ /* Coerce "normal" number ranges to normal number values, and only return BigInt-type values for numbers out of this range. */ return Number(rc).valueOf(); } return rc; }else{ const rc = capi.sqlite3_column_double(this.pointer, ndx); if(rc>Number.MAX_SAFE_INTEGER || rctoss3("The pointer property is read-only.") } Object.defineProperty(Stmt.prototype, 'pointer', prop); Object.defineProperty(DB.prototype, 'pointer', prop); } /** The OO API's public namespace. */ sqlite3.oo1 = { DB, Stmt }/*oo1 object*/; if(util.isUIThread()){ /** Functionally equivalent to DB(storageName,'c','kvvfs') except that it throws if the given storage name is not one of 'local' or 'session'. */ sqlite3.oo1.JsStorageDb = function(storageName='session'){ if('session'!==storageName && 'local'!==storageName){ toss3("JsStorageDb db name must be one of 'session' or 'local'."); } dbCtorHelper.call(this, { filename: storageName, flags: 'c', vfs: "kvvfs" }); }; const jdb = sqlite3.oo1.JsStorageDb; jdb.prototype = Object.create(DB.prototype); /** Equivalent to sqlite3_js_kvvfs_clear(). */ jdb.clearStorage = capi.sqlite3_js_kvvfs_clear; /** Clears this database instance's storage or throws if this instance has been closed. Returns the number of database blocks which were cleaned up. */ jdb.prototype.clearStorage = function(){ return jdb.clearStorage(affirmDbOpen(this).filename); }; /** Equivalent to sqlite3_js_kvvfs_size(). */ jdb.storageSize = capi.sqlite3_js_kvvfs_size; /** Returns the _approximate_ number of bytes this database takes up in its storage or throws if this instance has been closed. */ jdb.prototype.storageSize = function(){ return jdb.storageSize(affirmDbOpen(this).filename); }; }/*main-window-only bits*/ });