f81027ae9f
Fixes #19568 Values are not coerced to the desired type during deserialisation. This makes serde_v8 stricter. --------- Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com> |
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benches | ||
examples | ||
magic | ||
tests | ||
Cargo.toml | ||
de.rs | ||
error.rs | ||
keys.rs | ||
lib.rs | ||
payload.rs | ||
README.md | ||
ser.rs | ||
serializable.rs | ||
utils.rs |
serde_v8
Author: Aaron O'Mullan aaron.omullan@gmail.com
Serde support for encoding/decoding (rusty_)v8 values.
Broadly serde_v8
aims to provide an expressive but ~maximally efficient
encoding layer to biject rust & v8/js values. It's a core component of deno's
op-layer and is used to encode/decode all non-buffer values.
Original issue: denoland/deno#9540
Quickstart
serde_v8
fits naturally into the serde ecosystem, so if you've already used
serde
or serde_json
, serde_v8
's API should be very familiar.
serde_v8
exposes two key-functions:
to_v8
: mapsrust->v8
, similar toserde_json::to_string
, ...from_v8
: mapsv8->rust
, similar toserde_json::from_str
, ...
Best practices
Whilst serde_v8
is compatible with serde_json::Value
it's important to keep
in mind that serde_json::Value
is essentially a loosely-typed value (think
nested HashMaps), so when writing ops we recommend directly using rust
structs/tuples or primitives, since mapping to serde_json::Value
will add
extra overhead and result in slower ops.
I also recommend avoiding unecessary "wrappers", if your op takes a single-keyed struct, consider unwrapping that as a plain value unless you plan to add fields in the near-future.
Instead of returning "nothing" via Ok(json!({}))
, change your return type to
rust's unit type ()
and returning Ok(())
, serde_v8
will efficiently encode
that as a JS null
.
Advanced features
If you need to mix rust & v8 values in structs/tuples, you can use the special
serde_v8::Value
type, which will passthrough the original v8 value untouched
when encoding/decoding.
TODO
- Experiment with KeyCache to optimize struct keys
- Experiment with external v8 strings
- Explore using json-stringifier.cc's fast-paths for arrays
- Improve tests to test parity with
serde_json
(should be mostly interchangeable) - Consider a
Payload
type that's deserializable by itself (holds scope & value) - Ensure we return errors instead of panicking on
.unwrap()
s