extension: factor out routeDirectoryForChildren and createWritableDirectory

sort routes by specificity (__matchVarCount)

makes evals & watches much simpler; is prep work for writable tab
directory stuff
This commit is contained in:
Omar Rizwan 2021-07-22 17:53:17 -07:00
parent 38a5677dec
commit 9992d13680
2 changed files with 109 additions and 70 deletions

View File

@ -65,6 +65,9 @@ const utf8ArrayToString = (function() {
return utf8 => decoder.decode(utf8);
})();
// global so it can be hot-reloaded
window.Routes = {};
// Helper function: generates a full set of file operations that you
// can use as a route handler (so clients can read and write
// sections of the file, stat it to get its size and see it show up
@ -109,12 +112,14 @@ const routeWithContents = (function() {
// defined here.
async getattr(req) {
const data = await getData(req);
if (typeof data === 'undefined') { throw new UnixError(unix.ENOENT); }
return {
st_mode: unix.S_IFREG | 0444 | (setData ? 0222 : 0),
st_nlink: 1,
// you'll want to override this if getData() is slow, because
// getattr() gets called a lot more cavalierly than open().
st_size: toUtf8Array(await getData(req)).length
st_size: toUtf8Array(data).length
};
},
@ -122,6 +127,7 @@ const routeWithContents = (function() {
// data for all subsequent reads from that application.
async open(req) {
const data = await getData(req);
if (typeof data === 'undefined') { throw new UnixError(unix.ENOENT); }
return { fh: Cache.storeObject(req.path, toUtf8Array(data)) };
},
async read({fh, size, offset}) {
@ -160,8 +166,20 @@ const routeWithContents = (function() {
return routeWithContents;
})();
// global so it can be hot-reloaded
window.Routes = {};
function routeDirectoryForChildren(path) {
function depth(p) { return p === '/' ? 0 : (p.match(/\//g) || []).length; }
// find all direct children
let entries = Object.keys(Routes)
.filter(k => k.startsWith(path) && depth(k) === depth(path) + 1)
.map(k => k.substr((path === '/' ? 0 : path.length) + 1).split('/')[0])
// exclude entries with variables like :FILENAME in them
.filter(k => !k.includes("#") && !k.includes(":"));
entries = [".", "..", ...new Set(entries)];
return { readdir() { return { entries }; }, __isInfill: true };
}
function routeDefer(fn) { return fn; }
Routes["/tabs/create"] = {
usage: 'echo "https://www.google.com" > $0',
@ -214,6 +232,25 @@ Routes["/tabs/by-id"] = {
}
};
// TODO: temporarily disabled: make tab directory writable
// const tabIdDirectory = createWritableDirectory();
// Routes["/tabs/by-id/#TAB_ID"] = routeDefer(() => {
// const childrenRoute = routeDirectoryForChildren("/tabs/by-id/#TAB_ID");
// return {
// ...tabIdDirectory.routeForRoot, // so getattr is inherited
// async readdir(req) {
// const entries =
// [...(await tabIdDirectory.routeForRoot.readdir(req)).entries,
// ...(await childrenRoute.readdir(req)).entries];
// return {entries: [...new Set(entries)]};
// }
// };
// });
// Routes["/tabs/by-id/#TAB_ID/:FILENAME"] = tabIdDirectory.routeForFilename;
// TODO: can I trigger 1. nav to Finder and 2. nav to Terminal from toolbar click?
(function() {
const routeForTab = (readHandler, writeHandler) => routeWithContents(async ({tabId}) => {
const tab = await browser.tabs.get(tabId);
@ -246,8 +283,6 @@ Routes["/tabs/by-id"] = {
...routeFromScript(`document.body.innerHTML`)
};
// echo true > mnt/tabs/by-id/1644/active
// cat mnt/tabs/by-id/1644/active
Routes["/tabs/by-id/#TAB_ID/active"] = {
usage: ['cat $0',
'echo true > $0'],
@ -259,57 +294,60 @@ Routes["/tabs/by-id"] = {
)
};
})();
(function() {
const evals = {};
Routes["/tabs/by-id/#TAB_ID/evals"] = {
usage: 'ls $0',
async readdir({path, tabId}) {
return { entries: [".", "..",
...Object.keys(evals[tabId] || {}),
...Object.keys(evals[tabId] || {}).map(f => f + '.result')] };
},
getattr() {
return {
st_mode: unix.S_IFDIR | 0777, // writable so you can create/rm evals
st_nlink: 3,
st_size: 0,
};
function createWritableDirectory() {
const dir = {};
return {
directory: dir,
routeForRoot: {
usage: 'ls $0',
async readdir({path}) {
// get just last component of keys (filename)
return { entries: [".", "..",
...Object.keys(dir).map(
key => key.substr(key.lastIndexOf("/") + 1)
)] };
},
getattr() {
return {
st_mode: unix.S_IFDIR | 0777, // writable so you can create/rm evals
st_nlink: 3,
st_size: 0,
};
},
},
routeForFilename: {
usage: ['echo "2 + 2" > $0',
'cat $0.result'],
async mknod({path, mode}) {
dir[path] = '';
return {};
},
async unlink({path}) {
delete dir[path];
return {};
},
...routeWithContents(
async ({path}) => dir[path],
async ({path}, buf) => { dir[path] = buf; }
)
}
};
}
(function() {
const evals = createWritableDirectory();
Routes["/tabs/by-id/#TAB_ID/evals"] = evals.routeForRoot;
Routes["/tabs/by-id/#TAB_ID/evals/:FILENAME"] = {
usage: ['cat $0.result',
'echo "2 + 2" > $0'],
// NOTE: eval runs in extension's content script, not in original page JS context
async mknod({tabId, filename, mode}) {
evals[tabId] = evals[tabId] || {};
evals[tabId][filename] = { code: '' };
return {};
},
async unlink({tabId, filename}) {
delete evals[tabId][filename]; // TODO: also delete evals[tabId] if empty
return {};
},
...routeWithContents(async ({tabId, filename}) => {
const name = filename.replace(/\.result$/, '');
if (!evals[tabId] || !(name in evals[tabId])) { throw new UnixError(unix.ENOENT); }
if (filename.endsWith('.result')) {
return evals[tabId][name].result || '';
} else {
return evals[tabId][name].code;
}
}, async ({tabId, filename}, buf) => {
if (filename.endsWith('.result')) {
// FIXME: case where they try to write to .result file
} else {
const name = filename;
evals[tabId][name].code = buf;
evals[tabId][name].result = JSON.stringify((await browser.tabs.executeScript(tabId, {code: buf}))[0]) + '\n';
}
})
...evals.routeForFilename,
async write(req) {
const ret = await evals.routeForFilename.write(req);
const code = evals.directory[req.path];
evals.directory[req.path + '.result'] = JSON.stringify((await browser.tabs.executeScript(req.tabId, {code}))[0]) + '\n';
return ret;
}
};
})();
(function() {
@ -638,7 +676,7 @@ Routes["/runtime/routes.html"] = routeWithContents(async () => {
<body>
<p>(work in progress)</p>
<dl>
${Object.entries(Routes).map(([path, {usage, __isInfill}]) => {
` + Object.entries(Routes).map(([path, {usage, __isInfill}]) => {
if (__isInfill) { return ''; }
path = path.substring(1); // drop leading /
let usages = usage ? (Array.isArray(usage) ? usage : [usage]) : [];
@ -652,7 +690,7 @@ Routes["/runtime/routes.html"] = routeWithContents(async () => {
</ul>
</dd>
`;
}).join('\n')}
}).join('\n') + `
</dl>
</body>
</html>
@ -721,6 +759,7 @@ Routes["/runtime/background.js.html"] = routeWithContents(async () => {
`;
});
// Ensure that there are routes for all ancestors. This algorithm is
// probably not correct, but whatever. Basically, you need to start at
// the deepest level, fill in all the parents 1 level up that don't
@ -732,17 +771,7 @@ for (let i = 10; i >= 0; i--) {
path = path.substr(0, path.lastIndexOf("/"));
if (path == '') path = '/';
if (!Routes[path]) {
function depth(p) { return p === '/' ? 0 : (p.match(/\//g) || []).length; }
// find all direct children
let entries = Object.keys(Routes)
.filter(k => k.startsWith(path) && depth(k) === depth(path) + 1)
.map(k => k.substr((path === '/' ? 0 : path.length) + 1).split('/')[0]);
entries = [".", "..", ...new Set(entries)];
Routes[path] = { readdir() { return { entries }; }, __isInfill: true };
}
if (!Routes[path]) { Routes[path] = routeDirectoryForChildren(path); }
}
// I also think it would be better to compute this stuff on the fly,
// so you could patch more routes in at runtime, but I need to think
@ -752,12 +781,14 @@ for (let i = 10; i >= 0; i--) {
for (let key in Routes) {
// /tabs/by-id/#TAB_ID/url.txt -> RegExp \/tabs\/by-id\/(?<int$TAB_ID>[0-9]+)\/url.txt
Routes[key].__matchVarCount = 0;
Routes[key].__regex = new RegExp(
'^' + key
.split('/')
.map(keySegment => keySegment
.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')
.replace(/([#:])([A-Z_]+)/g, (_, sigil, varName) => {
Routes[key].__matchVarCount++;
return `(?<${sigil === '#' ? 'int$' : 'string$'}${varName}>` +
(sigil === '#' ? '[0-9]+' : '[^/]+') + `)`;
}))
@ -825,13 +856,17 @@ for (let key in Routes) {
}
}
// most specific (lowest matchVarCount) routes should match first
const sortedRoutes = Object.values(Routes).sort((a, b) =>
a.__matchVarCount - b.__matchVarCount
);
function tryMatchRoute(path) {
if (path.match(/\/\._[^\/]+$/)) {
// Apple Double ._whatever file for xattrs
throw new UnixError(unix.ENOTSUP);
}
for (let route of Object.values(Routes)) {
for (let route of sortedRoutes) {
const vars = route.__match(path);
if (vars) { return [route, vars]; }
}

View File

@ -6,16 +6,20 @@ global.chrome = {};
// run background.js
const {Routes, tryMatchRoute} = require('../extension/background');
function readdir(path) {
return Routes['/tabs/by-id/#TAB_ID'].readdir({path});
}
(async () => {
const tabRoute = await Routes['/tabs/by-id/#TAB_ID'].readdir();
const tabReaddir = await readdir('/tabs/by-id/#TAB_ID');
assert(['.', '..', 'url.txt', 'title.txt', 'text.txt']
.every(file => tabRoute.entries.includes(file)));
.every(file => tabReaddir.entries.includes(file)));
assert.deepEqual(await Routes['/'].readdir(),
{ entries: ['.', '..', 'windows', 'extensions', 'tabs', 'runtime'] });
assert.deepEqual(await Routes['/tabs'].readdir(),
{ entries: ['.', '..', 'create',
'by-id', 'by-title', 'last-focused'] });
'by-title', 'last-focused', 'by-id'] });
assert.deepEqual(tryMatchRoute('/'), [Routes['/'], {}]);