Can't compile to wasm

[DylanVerstraete]

  Compiling proc-macro-hack v0.5.19
   Compiling futures-core v0.3.15
   Compiling tinyvec v1.2.0
error: the wasm32-unknown-unknown target is not supported by default, you may need to enable the "js" feature. For more information see: https://docs.rs/getrandom/#webassembly-support
   --> /home/dylan/.cargo/registry/src/github.com-1ecc6299db9ec823/getrandom-0.2.3/src/lib.rs:219:9
    |
219 | /         compile_error!("the wasm32-unknown-unknown target is not supported by \
220 | |                         default, you may need to enable the \"js\" feature. \
221 | |                         For more information see: \
222 | |                         https://docs.rs/getrandom/#webassembly-support");
    | |_________________________________________________________________________^

error[E0433]: failed to resolve: use of undeclared crate or module `imp`
   --> /home/dylan/.cargo/registry/src/github.com-1ecc6299db9ec823/getrandom-0.2.3/src/lib.rs:246:5
    |
246 |     imp::getrandom_inner(dest)
    |     ^^^ use of undeclared crate or module `imp`

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0433`.
error: could not compile `getrandom`

To learn more, run the command again with --verbose.
warning: build failed, waiting for other jobs to finish...
error: build failed
Error: Compiling your crate to WebAssembly failed
Caused by: failed to execute `cargo build`: exited with exit status: 101
  full command: "cargo" "build" "--lib" "--release" "--target" "wasm32-unknown-unknown"

[clangenb]

This is most likely due to std leakage of the dev-dependencies.

the master branch includes a fix that should solve this: #120

[clangenb]

The fix only solves your issue if the api-client is the top-level crate, otherwise you need to add "resolver = 2" to your top-level Cargo.toml.

[DylanVerstraete]

@clangenb Does not seem to work by adding "resolver = 2"

[DylanVerstraete]

@clangenb https://github.com/DylanVerstraete/rust-wasm-substrate/blob/master/Cargo.toml

can you check this repo please?

[clangenb]

Well, when you want to compile to wasm you need to disable the std-features of the api-client with default-features = false

But this will strip most functionality.

[DylanVerstraete]

I can't compile to wasm without disabling std-features?

[clangenb]

I have just checked up on that and found out that std does not inherently break wasm support - but some std-libs do.

So, I reckon we'd need to make some adjustments to be able to support wasm with the std feature enabled. Without should be fine - as far as I know.

[DylanVerstraete]

If I disable default-features I get:

....
  Compiling sp-wasm-interface v4.0.0-dev (https://github.com/paritytech/substrate.git?branch=master#cf086eeb)
   Compiling sp-arithmetic v4.0.0-dev (https://github.com/paritytech/substrate.git?branch=master#cf086eeb)
   Compiling primitive-types v0.10.1
   Compiling sp-runtime-interface v4.0.0-dev (https://github.com/paritytech/substrate.git?branch=master#cf086eeb)
   Compiling sp-core v4.0.0-dev (https://github.com/paritytech/substrate.git?branch=master#cf086eeb)
   Compiling sp-io v4.0.0-dev (https://github.com/paritytech/substrate.git?branch=master#cf086eeb)
   Compiling frame-metadata v14.0.0-dev (https://github.com/paritytech/substrate.git?branch=master#cf086eeb)
   Compiling sp-inherents v4.0.0-dev (https://github.com/paritytech/substrate.git?branch=master#cf086eeb)
   Compiling sp-application-crypto v4.0.0-dev (https://github.com/paritytech/substrate.git?branch=master#cf086eeb)
error[E0046]: not all trait items implemented, missing: `Pair`
   --> /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/lib.rs:241:3
    |
241 |         impl $crate::CryptoType for Public {}
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `Pair` in implementation
    | 
   ::: /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/ed25519.rs:29:5
    |
29  |     crate::app_crypto!(super, ED25519);
    |     ----------------------------------- in this macro invocation
    |
    = note: this error originates in the macro `$crate::app_crypto_public_not_full_crypto` (in Nightly builds, run with -Z macro-backtrace for more info)
    = help: implement the missing item: `type Pair = Type;`

error[E0046]: not all trait items implemented, missing: `Pair`
   --> /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/lib.rs:442:3
    |
442 |         impl $crate::CryptoType for Signature {}
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `Pair` in implementation
    | 
   ::: /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/ed25519.rs:29:5
    |
29  |     crate::app_crypto!(super, ED25519);
    |     ----------------------------------- in this macro invocation
    |
    = note: this error originates in the macro `$crate::app_crypto_signature_not_full_crypto` (in Nightly builds, run with -Z macro-backtrace for more info)
    = help: implement the missing item: `type Pair = Type;`

error[E0046]: not all trait items implemented, missing: `Pair`
   --> /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/lib.rs:241:3
    |
241 |         impl $crate::CryptoType for Public {}
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `Pair` in implementation
    | 
   ::: /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/sr25519.rs:29:5
    |
29  |     crate::app_crypto!(super, SR25519);
    |     ----------------------------------- in this macro invocation
    |
    = note: this error originates in the macro `$crate::app_crypto_public_not_full_crypto` (in Nightly builds, run with -Z macro-backtrace for more info)
    = help: implement the missing item: `type Pair = Type;`

error[E0046]: not all trait items implemented, missing: `Pair`
   --> /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/lib.rs:442:3
    |
442 |         impl $crate::CryptoType for Signature {}
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `Pair` in implementation
    | 
   ::: /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/sr25519.rs:29:5
    |
29  |     crate::app_crypto!(super, SR25519);
    |     ----------------------------------- in this macro invocation
    |
    = note: this error originates in the macro `$crate::app_crypto_signature_not_full_crypto` (in Nightly builds, run with -Z macro-backtrace for more info)
    = help: implement the missing item: `type Pair = Type;`

error[E0046]: not all trait items implemented, missing: `Pair`
   --> /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/lib.rs:241:3
    |
241 |         impl $crate::CryptoType for Public {}
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `Pair` in implementation
    | 
   ::: /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/ecdsa.rs:29:5
    |
29  |     crate::app_crypto!(super, ECDSA);
    |     --------------------------------- in this macro invocation
    |
    = note: this error originates in the macro `$crate::app_crypto_public_not_full_crypto` (in Nightly builds, run with -Z macro-backtrace for more info)
    = help: implement the missing item: `type Pair = Type;`

error[E0046]: not all trait items implemented, missing: `Pair`
   --> /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/lib.rs:442:3
    |
442 |         impl $crate::CryptoType for Signature {}
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `Pair` in implementation
    | 
   ::: /home/dylan/.cargo/git/checkouts/substrate-7e08433d4c370a21/cf086ee/primitives/application-crypto/src/ecdsa.rs:29:5
    |
29  |     crate::app_crypto!(super, ECDSA);
    |     --------------------------------- in this macro invocation
    |
    = note: this error originates in the macro `$crate::app_crypto_signature_not_full_crypto` (in Nightly builds, run with -Z macro-backtrace for more info)
    = help: implement the missing item: `type Pair = Type;`

error: aborting due to 6 previous errors

For more information about this error, try `rustc --explain E0046`.
error: could not compile `sp-application-crypto`

To learn more, run the command again with --verbose.
warning: build failed, waiting for other jobs to finish...
error: build failed
Error: Compiling your crate to WebAssembly failed
Caused by: failed to execute `cargo build`: exited with exit status: 101
  full command: "cargo" "build" "--lib" "--release" "--target" "wasm32-unknown-unknown"

[clangenb]

There seemed to be a tiny feature-flag bug on our side. Fixed in #137

[DylanVerstraete]

@clangenb okay, will I be able to do anything with the client without std-features?

[clangenb]

Currently, it is essentially the compose_extrinsic_offline! macro, which is not really much. It allows you only to compose and to sign an extrinsic.

[DylanVerstraete]

@clangenb although it compiles now I get following error trying to import the API

➜ wasm-pack build
[INFO]: Checking for the Wasm target...
[INFO]: Compiling to Wasm...
   Compiling rust-substrate-api-client v0.1.0 (/home/dylan/Projects/rust-substrate-api-client)
error[E0432]: unresolved import `substrate_api_client::Api`
  --> src/lib.rs:13:5
   |
13 | use substrate_api_client::Api;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ no `Api` in the root

error: aborting due to previous error

For more information about this error, try `rustc --explain E0432`.
error: could not compile `rust-substrate-api-client`

To learn more, run the command again with --verbose.
Error: Compiling your crate to WebAssembly failed
Caused by: failed to execute `cargo build`: exited with exit status: 101
  full command: "cargo" "build" "--lib" "--release" "--target" "wasm32-unknown-unknown"

[clangenb]

If you disabled std in the client you ony get access to compose_extrinsic_offline! macro. This no part of the Api strut, but exported to top-level.

use substrate_api_client::compose_extrinsic_offline;