balena-io-modules / balena-temen Goto Github PK

• base64encode
• base64decode

Specification allows to evaluate expression containing relative paths. Currently there's no support for this.

• Go through the grammar and test all possibilities (= expressions)

Attaching examples found by fuzzer
slow-examples.zip

• chrono doesn't support wasm32 (see chronotope/chrono#243 & chronotope/chrono#287)
• we have added a workaround from the jjpe/wasm branch, which works, but ...

src/context.rs:

#[cfg(not(target_arch = "wasm32"))]
fn utc_now() -> DateTime<Utc> {
    Utc::now()
}

// chrono crate doesn't support wasm32 arch yet, workaround
#[cfg(target_arch = "wasm32")]
fn utc_now() -> DateTime<Utc> {
    let now = js_sys::Date::new_0();
    let millisecs_since_unix_epoch: u64 = now.get_time() as u64;
    let secs = millisecs_since_unix_epoch / 1000;
    let nanos = 1_000_000 * (millisecs_since_unix_epoch - 1000 * secs);
    let naive = NaiveDateTime::from_timestamp(secs as i64, nanos as u32);
    DateTime::from_utc(naive, Utc)
}

Function now isn't implemented.

See Functions.

Following filters are not implemented:

• slugify
• trim
• date
• time
• datetime

See Supported Filters.

Current implementation of the fuzzer is kind of useless. There's no way how to get the crashing input, etc. Useless fuzzer was removed.

We have to come up with some fuzzing strategy like:

• when to run it,
• where to run it,
• for how long,
• how often,
• etc.

Once new uuid crate is released and #352 fixed, we can remove our uuid & rand workaround.

• Remove rand dependency
• Enable v4 feature (uuid crate)
• Enable wasm-bindgen feature (uuid crate, wasm32 arch)
• Replace custom uuidv4() fn body with Uuid::new_v4()

Once all features will be in place, fully working, optimise the whole crate, because it:

• contains unnecessary allocations,
• does not leverage references, lifetimes, cow,
• etc.

Issue on rand side: rust-random/rand#682
See also #48

Reproducible Node case:

const bt = require('balena-temen');

console.log(
    bt.evaluate({
        "uuid": {
            "$$eval": "uuidv4()"
        }
    })
);

The error message:

panicked at 'could not initialize thread_rng: No entropy sources available (permanently unavailable)', /Users/robertvojta/.cargo/registry/src/github.com-1ecc6299db9ec823/rand-0.5.5/src/rngs/thread.rs:84:17
wasm://wasm/004488ea:574

RuntimeError: unreachable
    at __rust_start_panic (wasm-function[573]:1)
    at rust_panic (wasm-function[570]:30)
    at std::panicking::rust_panic_with_hook::h6790e8431e342a60 (wasm-function[565]:444)
    at std::panicking::continue_panic_fmt::h3b66c044a41127bf (wasm-function[564]:120)
    at std::panicking::begin_panic_fmt::h522439ba8a0fbac4 (wasm-function[561]:95)
    at rand::rngs::thread::THREAD_RNG_KEY::__init::_$u7b$$u7b$closure$u7d$$u7d$::hdd28f475617c5274 (wasm-function[357]:91)
    at rand::rngs::thread::thread_rng::hef4638d394e756b1 (wasm-function[356]:1024)
    at uuid::v4::_$LT$impl$u20$uuid..Uuid$GT$::new_v4::h9644a31e3bf57f8d (wasm-function[345]:14)
    at balena_temen::builtin::function::uuidv4::uuidv4::h3ce10819a87f445f (wasm-function[200]:18)
    at balena_temen::engine::Engine::eval_function::he1b50994ba503a6b (wasm-function[233]:943)

Same error in both nodeJS & browser.

@mikesimos Flowdock thread message:

Just an update, here is a list of DSL generators (+validators ideally) we use/ll be using in balena configuration:

• DH-Param (could be the output of require('dhparam')(bits))
• RSA Keypair
• x.509 CACert
• x.509 Cert
• EC PrivateKey
• EC keyid
• EC Cert

More info about EC *.

Imagine you have a JSON like this one ...

{
  "uuid": {
    "$$eval": "uuidv4()"
  },
  "id: {
    "$$eval": "ssid | slugify"
  },
  "ssid": "Zrzka 5G"
}

... and you'd like to evaluate everything at once to get something like ...

{
  "uuid": "2a0b9f5a-04e8-483e-bb3c-c889822afc67",
  "id": "zrzka-5g",
  "ssid": "Zrzka 5G"
}

... we should provide a helper function for this, so, one can do it with one call. It's possible today, but one has to find all $$eval and evaluate them one by one.

@cyplo WDYT?

We should replace error-chain with custom error type allowing us to provide more precise error messages like which part of the expression is wrong, etc.

We have to provide a public API for users with the ability to normalize identifier. It means conversion from relative identifier to an absolute one (remove this and super keywords).

Till 0.1, even patch version can break public API. Once all features will be in place, working, API should be stabilised, 0.1 released and then we should follow semantic versioning.

We need to add benchmarks, but we have to check with CI guys how stable in terms of performance is our CI, etc. Or we should run them locally on our machines with predictable performance.

Not implemented for the wasm32-unknown-unknown target.