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+/*
+ 2022-05-22
+
+ 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.
+
+ ***********************************************************************
+
+ A basic test script for sqlite3-worker1.js.
+
+ Note that the wrapper interface demonstrated in
+ demo-worker1-promiser.js is much easier to use from client code, as it
+ lacks the message-passing acrobatics demonstrated in this file.
+*/
+'use strict';
+(function(){
+ const T = self.SqliteTestUtil;
+ const SW = new Worker("jswasm/sqlite3-worker1.js");
+ const DbState = {
+ id: undefined
+ };
+ const eOutput = document.querySelector('#test-output');
+ const log = console.log.bind(console);
+ const logHtml = function(cssClass,...args){
+ log.apply(this, args);
+ const ln = document.createElement('div');
+ if(cssClass) ln.classList.add(cssClass);
+ ln.append(document.createTextNode(args.join(' ')));
+ eOutput.append(ln);
+ };
+ const warn = console.warn.bind(console);
+ const error = console.error.bind(console);
+ const toss = (...args)=>{throw new Error(args.join(' '))};
+
+ SW.onerror = function(event){
+ error("onerror",event);
+ };
+
+ let startTime;
+
+ /**
+ A queue for callbacks which are to be run in response to async
+ DB commands. See the notes in runTests() for why we need
+ this. The event-handling plumbing of this file requires that
+ any DB command which includes a `messageId` property also have
+ a queued callback entry, as the existence of that property in
+ response payloads is how it knows whether or not to shift an
+ entry off of the queue.
+ */
+ const MsgHandlerQueue = {
+ queue: [],
+ id: 0,
+ push: function(type,callback){
+ this.queue.push(callback);
+ return type + '-' + (++this.id);
+ },
+ shift: function(){
+ return this.queue.shift();
+ }
+ };
+
+ const testCount = ()=>{
+ logHtml("","Total test count:",T.counter+". Total time =",(performance.now() - startTime),"ms");
+ };
+
+ const logEventResult = function(ev){
+ const evd = ev.result;
+ logHtml(evd.errorClass ? 'error' : '',
+ "runOneTest",ev.messageId,"Worker time =",
+ (ev.workerRespondTime - ev.workerReceivedTime),"ms.",
+ "Round-trip event time =",
+ (performance.now() - ev.departureTime),"ms.",
+ (evd.errorClass ? evd.message : "")//, JSON.stringify(evd)
+ );
+ };
+
+ const runOneTest = function(eventType, eventArgs, callback){
+ T.assert(eventArgs && 'object'===typeof eventArgs);
+ /* ^^^ that is for the testing and messageId-related code, not
+ a hard requirement of all of the Worker-exposed APIs. */
+ const messageId = MsgHandlerQueue.push(eventType,function(ev){
+ logEventResult(ev);
+ if(callback instanceof Function){
+ callback(ev);
+ testCount();
+ }
+ });
+ const msg = {
+ type: eventType,
+ args: eventArgs,
+ dbId: DbState.id,
+ messageId: messageId,
+ departureTime: performance.now()
+ };
+ log("Posting",eventType,"message to worker dbId="+(DbState.id||'default')+':',msg);
+ SW.postMessage(msg);
+ };
+
+ /** Methods which map directly to onmessage() event.type keys.
+ They get passed the inbound event.data. */
+ const dbMsgHandler = {
+ open: function(ev){
+ DbState.id = ev.dbId;
+ log("open result",ev);
+ },
+ exec: function(ev){
+ log("exec result",ev);
+ },
+ export: function(ev){
+ log("export result",ev);
+ },
+ error: function(ev){
+ error("ERROR from the worker:",ev);
+ logEventResult(ev);
+ },
+ resultRowTest1: function f(ev){
+ if(undefined === f.counter) f.counter = 0;
+ if(null === ev.rowNumber){
+ /* End of result set. */
+ T.assert(undefined === ev.row)
+ .assert(Array.isArray(ev.columnNames))
+ .assert(ev.columnNames.length);
+ }else{
+ T.assert(ev.rowNumber > 0);
+ ++f.counter;
+ }
+ //log("exec() result row:",ev);
+ T.assert(null === ev.rowNumber || 'number' === typeof ev.row.b);
+ }
+ };
+
+ /**
+ "The problem" now is that the test results are async. We
+ know, however, that the messages posted to the worker will
+ be processed in the order they are passed to it, so we can
+ create a queue of callbacks to handle them. The problem
+ with that approach is that it's not error-handling
+ friendly, in that an error can cause us to bypass a result
+ handler queue entry. We have to perform some extra
+ acrobatics to account for that.
+
+ Problem #2 is that we cannot simply start posting events: we
+ first have to post an 'open' event, wait for it to respond, and
+ collect its db ID before continuing. If we don't wait, we may
+ well fire off 10+ messages before the open actually responds.
+ */
+ const runTests2 = function(){
+ const mustNotReach = ()=>{
+ throw new Error("This is not supposed to be reached.");
+ };
+ runOneTest('exec',{
+ sql: ["create table t(a,b);",
+ "insert into t(a,b) values(1,2),(3,4),(5,6)"
+ ],
+ resultRows: [], columnNames: []
+ }, function(ev){
+ ev = ev.result;
+ T.assert(0===ev.resultRows.length)
+ .assert(0===ev.columnNames.length);
+ });
+ runOneTest('exec',{
+ sql: 'select a a, b b from t order by a',
+ resultRows: [], columnNames: [], saveSql:[]
+ }, function(ev){
+ ev = ev.result;
+ T.assert(3===ev.resultRows.length)
+ .assert(1===ev.resultRows[0][0])
+ .assert(6===ev.resultRows[2][1])
+ .assert(2===ev.columnNames.length)
+ .assert('b'===ev.columnNames[1]);
+ });
+ //if(1){ error("Returning prematurely for testing."); return; }
+ runOneTest('exec',{
+ sql: 'select a a, b b from t order by a',
+ resultRows: [], columnNames: [],
+ rowMode: 'object'
+ }, function(ev){
+ ev = ev.result;
+ T.assert(3===ev.resultRows.length)
+ .assert(1===ev.resultRows[0].a)
+ .assert(6===ev.resultRows[2].b)
+ });
+ runOneTest('exec',{sql:'intentional_error'}, mustNotReach);
+ // Ensure that the message-handler queue survives ^^^ that error...
+ runOneTest('exec',{
+ sql:'select 1',
+ resultRows: [],
+ //rowMode: 'array', // array is the default in the Worker interface
+ }, function(ev){
+ ev = ev.result;
+ T.assert(1 === ev.resultRows.length)
+ .assert(1 === ev.resultRows[0][0]);
+ });
+ runOneTest('exec',{
+ sql: 'select a a, b b from t order by a',
+ callback: 'resultRowTest1',
+ rowMode: 'object'
+ }, function(ev){
+ T.assert(3===dbMsgHandler.resultRowTest1.counter);
+ dbMsgHandler.resultRowTest1.counter = 0;
+ });
+ runOneTest('exec',{
+ sql:[
+ "pragma foreign_keys=0;",
+ // ^^^ arbitrary query with no result columns
+ "select a, b from t order by a desc;",
+ "select a from t;"
+ // exec() only honors SELECT results from the first
+ // statement with result columns (regardless of whether
+ // it has any rows).
+ ],
+ rowMode: 1,
+ resultRows: []
+ },function(ev){
+ const rows = ev.result.resultRows;
+ T.assert(3===rows.length).
+ assert(6===rows[0]);
+ });
+ runOneTest('exec',{sql: 'delete from t where a>3'});
+ runOneTest('exec',{
+ sql: 'select count(a) from t',
+ resultRows: []
+ },function(ev){
+ ev = ev.result;
+ T.assert(1===ev.resultRows.length)
+ .assert(2===ev.resultRows[0][0]);
+ });
+ runOneTest('export',{}, function(ev){
+ ev = ev.result;
+ log("export result:",ev);
+ T.assert('string' === typeof ev.filename)
+ .assert(ev.byteArray instanceof Uint8Array)
+ .assert(ev.byteArray.length > 1024)
+ .assert('application/x-sqlite3' === ev.mimetype);
+ });
+ /***** close() tests must come last. *****/
+ runOneTest('close',{unlink:true},function(ev){
+ ev = ev.result;
+ T.assert('string' === typeof ev.filename);
+ });
+ runOneTest('close',{unlink:true},function(ev){
+ ev = ev.result;
+ T.assert(undefined === ev.filename);
+ logHtml('warning',"This is the final test.");
+ });
+ logHtml('warning',"Finished posting tests. Waiting on async results.");
+ };
+
+ const runTests = function(){
+ /**
+ Design decision time: all remaining tests depend on the 'open'
+ command having succeeded. In order to support multiple DBs, the
+ upcoming commands ostensibly have to know the ID of the DB they
+ want to talk to. We have two choices:
+
+ 1) We run 'open' and wait for its response, which contains the
+ db id.
+
+ 2) We have the Worker automatically use the current "default
+ db" (the one which was most recently opened) if no db id is
+ provided in the message. When we do this, the main thread may
+ well fire off _all_ of the test messages before the 'open'
+ actually responds, but because the messages are handled on a
+ FIFO basis, those after the initial 'open' will pick up the
+ "default" db. However, if the open fails, then all pending
+ messages (until next next 'open', at least) except for 'close'
+ will fail and we have no way of cancelling them once they've
+ been posted to the worker.
+
+ Which approach we use below depends on the boolean value of
+ waitForOpen.
+ */
+ const waitForOpen = 1,
+ simulateOpenError = 0 /* if true, the remaining tests will
+ all barf if waitForOpen is
+ false. */;
+ logHtml('',
+ "Sending 'open' message and",(waitForOpen ? "" : "NOT ")+
+ "waiting for its response before continuing.");
+ startTime = performance.now();
+ runOneTest('open', {
+ filename:'testing2.sqlite3',
+ simulateError: simulateOpenError
+ }, function(ev){
+ log("open result",ev);
+ T.assert('testing2.sqlite3'===ev.result.filename)
+ .assert(ev.dbId)
+ .assert(ev.messageId)
+ .assert('string' === typeof ev.result.vfs);
+ DbState.id = ev.dbId;
+ if(waitForOpen) setTimeout(runTests2, 0);
+ });
+ if(!waitForOpen) runTests2();
+ };
+
+ SW.onmessage = function(ev){
+ if(!ev.data || 'object'!==typeof ev.data){
+ warn("Unknown sqlite3-worker message type:",ev);
+ return;
+ }
+ ev = ev.data/*expecting a nested object*/;
+ //log("main window onmessage:",ev);
+ if(ev.result && ev.messageId){
+ /* We're expecting a queued-up callback handler. */
+ const f = MsgHandlerQueue.shift();
+ if('error'===ev.type){
+ dbMsgHandler.error(ev);
+ return;
+ }
+ T.assert(f instanceof Function);
+ f(ev);
+ return;
+ }
+ switch(ev.type){
+ case 'sqlite3-api':
+ switch(ev.result){
+ case 'worker1-ready':
+ log("Message:",ev);
+ self.sqlite3TestModule.setStatus(null);
+ runTests();
+ return;
+ default:
+ warn("Unknown sqlite3-api message type:",ev);
+ return;
+ }
+ default:
+ if(dbMsgHandler.hasOwnProperty(ev.type)){
+ try{dbMsgHandler[ev.type](ev);}
+ catch(err){
+ error("Exception while handling db result message",
+ ev,":",err);
+ }
+ return;
+ }
+ warn("Unknown sqlite3-api message type:",ev);
+ }
+ };
+ log("Init complete, but async init bits may still be running.");
+ log("Installing Worker into global scope SW for dev purposes.");
+ self.SW = SW;
+})();
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