diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml index f15ff46bc..284645a01 100644 --- a/.github/workflows/build.yml +++ b/.github/workflows/build.yml @@ -29,7 +29,7 @@ jobs: with: command: build-all - light-client-wasm: + build-light-client-wasm: runs-on: ubuntu-latest steps: - uses: actions/checkout@v2 diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml index 33f7b933d..19e0916a0 100644 --- a/.github/workflows/test.yml +++ b/.github/workflows/test.yml @@ -69,6 +69,15 @@ jobs: with: command: test-all-features args: -p tendermint-light-client + # From https://rustwasm.github.io/docs/wasm-bindgen/wasm-bindgen-test/continuous-integration.html#github-actions + tendermint-light-client-js: + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v2 + - name: Install wasm-pack + run: curl https://rustwasm.github.io/wasm-pack/installer/init.sh -sSf | sh + - run: wasm-pack test --headless --chrome ./light-client-js/ + - run: wasm-pack test --headless --firefox ./light-client-js/ tendermint-light-node: runs-on: ubuntu-latest steps: diff --git a/.gitignore b/.gitignore index 46c3ebed2..f971349c6 100644 --- a/.gitignore +++ b/.gitignore @@ -17,3 +17,9 @@ Cargo.lock # Proptest regressions dumps **/*.proptest-regressions + +# Light Client WASM +light-client-js/pkg/ +light-client-js/examples/verifier-web/node_modules/ +light-client-js/examples/verifier-web/dist/ +light-client-js/examples/verifier-web/package-lock.json diff --git a/CHANGELOG.md b/CHANGELOG.md index a620ec1bc..9916945b2 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -1,11 +1,18 @@ -## Unreleased +## Unreleased ### FEATURES * `[tendermint-abci]` Release minimal framework for building ABCI applications in Rust ([#794]) +* `[tendermint-light-client-js]` First release of the + `tendermint-light-client-js` crate to provide access to Tendermint Light + Client functionality from WASM. This only provides access to the `verify` + method at present, exclusively provides access to block verification. This + does not include network access or the Light Client's bisection algorithm + ([#812]) [#794]: https://github.com/informalsystems/tendermint-rs/pull/794 +[#812]: https://github.com/informalsystems/tendermint-rs/pull/812 ## v0.18.1 diff --git a/Cargo.toml b/Cargo.toml index 034bac036..9f6ff41bb 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -3,6 +3,7 @@ members = [ "abci", "light-client", + "light-client-js", "light-node", "p2p", "proto", diff --git a/light-client-js/Cargo.toml b/light-client-js/Cargo.toml new file mode 100644 index 000000000..97e7a8753 --- /dev/null +++ b/light-client-js/Cargo.toml @@ -0,0 +1,47 @@ +[package] +name = "tendermint-light-client-js" +version = "0.18.1" +authors = [ + "Romain Ruetschi ", + "Thane Thomson " +] +edition = "2018" +license = "Apache-2.0" +description = """ + tendermint-light-client-js provides a lightweight, WASM-based interface to + the Tendermint Light Client's verification functionality. + """ +repository = "https://github.com/informalsystems/tendermint-rs" + +[lib] +crate-type = ["cdylib", "rlib"] + +[features] +default = ["console_error_panic_hook"] + +[dependencies] +serde = { version = "1.0", features = [ "derive" ] } +serde_json = "1.0" +tendermint = { version = "0.18.1", path = "../tendermint" } +tendermint-light-client = { version = "0.18.1", path = "../light-client", default-features = false } +wasm-bindgen = { version = "0.2.63", features = [ "serde-serialize" ] } + +# The `console_error_panic_hook` crate provides better debugging of panics by +# logging them with `console.error`. This is great for development, but requires +# all the `std::fmt` and `std::panicking` infrastructure, so isn't great for +# code size when deploying. +console_error_panic_hook = { version = "0.1.6", optional = true } + +# `wee_alloc` is a tiny allocator for wasm that is only ~1K in code size +# compared to the default allocator's ~10K. It is slower than the default +# allocator, however. +# +# Unfortunately, `wee_alloc` requires nightly Rust when targeting wasm for now. +wee_alloc = { version = "0.4.5", optional = true } + +[dev-dependencies] +wasm-bindgen-test = "0.3.13" + +[profile.release] +# Tell `rustc` to optimize for small code size. +opt-level = "s" diff --git a/light-client-js/README.md b/light-client-js/README.md new file mode 100644 index 000000000..09c595760 --- /dev/null +++ b/light-client-js/README.md @@ -0,0 +1,17 @@ +# Light-Client API for JavaScript + +At present this just exposes the [Tendermint Light Client]'s verification logic +via WASM. This allows simple access to verification from JavaScript: + +```javascript +import * as LightClient from 'tendermint-light-client-js'; + +// Verify an untrusted block against a trusted one, given the specified options +// and current date/time. +let verdict = LightClient.verify(untrusted, trusted, options, now); +``` + +For an example of how to use this, please see the [verifier-web example]. + +[Tendermint Light Client]: ../light-client/ +[verifier-web example]: ./examples/verifier-web/ diff --git a/light-client-js/examples/verifier-web/README.md b/light-client-js/examples/verifier-web/README.md new file mode 100644 index 000000000..a249c75f1 --- /dev/null +++ b/light-client-js/examples/verifier-web/README.md @@ -0,0 +1,69 @@ +# Web-Based Light Client Verification + +This folder contains a simple *example* web application demonstrating +Tendermint Light Client verification. + +## Requirements + +* Rust stable latest +* NodeJS (tested with v14.15.5) +* [wasm-pack] + +## Try it out + +You first need to build a few things before you can try this example out +locally. + +### Step 1: Building the WASM binary + +From the [`light-client-js` folder](../../): + +```bash +wasm-pack build +``` + +This will build our WASM binary and JavaScript/TypeScript wrappers and place +them into a `pkg` directory. + +### Step 2: Build/run the example + +From this directory (`light-client-js/examples/verifier-web`): + +```bash +# Install all dependencies +npm install + +# Build/start the example app +npm run start +``` + +This should build the example and start a server at http://localhost:8080 + +### Step 3: Input your data + +When you open up at http://localhost:8080, you should see something like the +following: + +![screenshot1](screenshot1.png) + +Copy/paste the JSON representation of a trusted block alongside that of the +untrusted block you wish to verify into the supplied editors. Configure your +desired Light Client parameters, as well as the timestamp at which you want to +check whether the untrusted block is trustworthy, and click the **Verify** +button. + +This will show you the raw JSON object received back from the verifier. + +![screenshot2](screenshot2.png) + +## Limitations + +1. This example only demonstrates *verification*, and is pretty manual right + now (you must manually copy/paste the JSON representations of untrusted and + trusted blocks, and supply options/timestamps manually). No network I/O + happens here, so bring your own I/O to fetch light blocks. +2. The WASM binary built in step 1 only works for bundled web applications + (e.g. using [webpack]). + +[wasm-pack]: https://rustwasm.github.io/docs/wasm-pack/introduction.html +[webpack]: https://webpack.js.org/ diff --git a/light-client-js/examples/verifier-web/bootstrap.js b/light-client-js/examples/verifier-web/bootstrap.js new file mode 100644 index 000000000..7934d627e --- /dev/null +++ b/light-client-js/examples/verifier-web/bootstrap.js @@ -0,0 +1,5 @@ +// A dependency graph that contains any wasm must all be imported +// asynchronously. This `bootstrap.js` file does the single async import, so +// that no one else needs to worry about it again. +import("./index.js") + .catch(e => console.error("Error importing `index.js`:", e)); diff --git a/light-client-js/examples/verifier-web/index.html b/light-client-js/examples/verifier-web/index.html new file mode 100644 index 000000000..88d5cdce5 --- /dev/null +++ b/light-client-js/examples/verifier-web/index.html @@ -0,0 +1,106 @@ + + + + + + Tendermint Light Client WASM Example + + + + +
+
+

Tendermint Light Client WASM Example

+

+ This example demonstrates how to make use of the + Tendermint Light Client + WASM build in a simple web application. +

+
+
+ +
+
+
+
+

Untrusted Block

+
+
+ +
+

Trusted Block

+
+
+
+
+
+ +
+
+

Options

+
+
+
+ +
+ +
+

Must be in the format: numerator/denominator

+
+
+ +
+
+ +
+ +
+

A.k.a. "unbonding period", in seconds

+
+
+ +
+
+ +
+ +
+

In seconds

+
+
+ +
+
+ +
+ +
+

Timestamp in RFC3339 format for which you want to verify the block

+
+
+
+
+
+ +
+
+ +
+
+ +
+
+

Verdict

+ 

+  

+

+
+
+
diff --git a/light-client-js/examples/verifier-web/index.js b/light-client-js/examples/verifier-web/index.js
new file mode 100644
index 000000000..42890cf00
--- /dev/null
+++ b/light-client-js/examples/verifier-web/index.js
@@ -0,0 +1,186 @@
+import * as monaco from 'monaco-editor';
+import * as LightClient from 'tendermint-light-client-js';
+
+let untrustedBlockEditor = monaco.editor.create(document.getElementById("untrusted-block-editor"), {
+    value: JSON.stringify({
+        "signed_header": {
+            "header": {
+                "version": {
+                    "block": "11",
+                    "app": "0"
+                },
+                "chain_id": "test-chain",
+                "height": "4",
+                "time": "1970-01-01T00:00:04Z",
+                "last_block_id": null,
+                "last_commit_hash": null,
+                "data_hash": null,
+                "validators_hash": "75E6DD63C2DC2B58FE0ED82792EAB369C4308C7EC16B69446382CC4B41D46068",
+                "next_validators_hash": "C8CFFADA9808F685C4111693E1ADFDDBBEE9B9493493BEF805419F143C5B0D0A",
+                "consensus_hash": "75E6DD63C2DC2B58FE0ED82792EAB369C4308C7EC16B69446382CC4B41D46068",
+                "app_hash": "",
+                "last_results_hash": null,
+                "evidence_hash": null,
+                "proposer_address": "6AE5C701F508EB5B63343858E068C5843F28105F"
+            },
+            "commit": {
+                "height": "4",
+                "round": 1,
+                "block_id": {
+                    "hash": "D0E7B0C678E290DA835BB26EE826472D66B6A306801E5FE0803C5320C554610A",
+                    "part_set_header": {
+                        "total": 1,
+                        "hash": "D0E7B0C678E290DA835BB26EE826472D66B6A306801E5FE0803C5320C554610A"
+                    }
+                },
+                "signatures": [
+                    {
+                        "block_id_flag": 2,
+                        "validator_address": "6AE5C701F508EB5B63343858E068C5843F28105F",
+                        "timestamp": "1970-01-01T00:00:04Z",
+                        "signature": "lTGBsjVI6YwIRcxQ6Lct4Q+xrtJc9h3648c42uWe4MpSgy4rUI5g71AEpG90Tbn0PRizjKgCPhokPpQoQLiqAg=="
+                    }
+                ]
+            }
+        },
+        "validator_set": {
+            "total_voting_power": "0",
+            "validators": [
+                {
+                    "address": "6AE5C701F508EB5B63343858E068C5843F28105F",
+                    "pub_key": {
+                        "type": "tendermint/PubKeyEd25519",
+                        "value": "GQEC/HB4sDBAVhHtUzyv4yct9ZGnudaP209QQBSTfSQ="
+                    },
+                    "voting_power": "50",
+                    "proposer_priority": null
+                }
+            ]
+        },
+        "next_validator_set": {
+            "total_voting_power": "0",
+            "validators": [
+                {
+                    "address": "C479DB6F37AB9757035CFBE10B687E27668EE7DF",
+                    "pub_key": {
+                        "type": "tendermint/PubKeyEd25519",
+                        "value": "3wf60CidQcsIO7TksXzEZsJefMUFF73k6nP1YeEo9to="
+                    },
+                    "voting_power": "50",
+                    "proposer_priority": null
+                }
+            ]
+        },
+        "provider": "BADFADAD0BEFEEDC0C0ADEADBEEFC0FFEEFACADE"
+    }, null, 2),
+    language: 'json',
+    minimap: { enabled: false }
+});
+
+let trustedBlockEditor = monaco.editor.create(document.getElementById("trusted-block-editor"), {
+    value: JSON.stringify({
+        "signed_header": {
+            "header": {
+                "version": {
+                    "block": "11",
+                    "app": "0"
+                },
+                "chain_id": "test-chain",
+                "height": "3",
+                "time": "1970-01-01T00:00:03Z",
+                "last_block_id": null,
+                "last_commit_hash": null,
+                "data_hash": null,
+                "validators_hash": "75E6DD63C2DC2B58FE0ED82792EAB369C4308C7EC16B69446382CC4B41D46068",
+                "next_validators_hash": "75E6DD63C2DC2B58FE0ED82792EAB369C4308C7EC16B69446382CC4B41D46068",
+                "consensus_hash": "75E6DD63C2DC2B58FE0ED82792EAB369C4308C7EC16B69446382CC4B41D46068",
+                "app_hash": "",
+                "last_results_hash": null,
+                "evidence_hash": null,
+                "proposer_address": "6AE5C701F508EB5B63343858E068C5843F28105F"
+            },
+            "commit": {
+                "height": "3",
+                "round": 1,
+                "block_id": {
+                    "hash": "AAB1B09D5FADAAE7CDF3451961A63F810DB73BF3214A7B74DBA36C52EDF1A793",
+                    "part_set_header": {
+                        "total": 1,
+                        "hash": "AAB1B09D5FADAAE7CDF3451961A63F810DB73BF3214A7B74DBA36C52EDF1A793"
+                    }
+                },
+                "signatures": [
+                    {
+                        "block_id_flag": 2,
+                        "validator_address": "6AE5C701F508EB5B63343858E068C5843F28105F",
+                        "timestamp": "1970-01-01T00:00:03Z",
+                        "signature": "xn0eSsHYIsqUbmfAiJq1R0hqZbfuIjs5Na1c88EC1iPTuQAesKg9I7nXG4pk8d6U5fU4GysNLk5I4f7aoefOBA=="
+                    }
+                ]
+            }
+        },
+        "validator_set": {
+            "total_voting_power": "0",
+            "validators": [
+                {
+                    "address": "6AE5C701F508EB5B63343858E068C5843F28105F",
+                    "pub_key": {
+                        "type": "tendermint/PubKeyEd25519",
+                        "value": "GQEC/HB4sDBAVhHtUzyv4yct9ZGnudaP209QQBSTfSQ="
+                    },
+                    "voting_power": "50",
+                    "proposer_priority": null
+                }
+            ]
+        },
+        "next_validator_set": {
+            "total_voting_power": "0",
+            "validators": [
+                {
+                    "address": "6AE5C701F508EB5B63343858E068C5843F28105F",
+                    "pub_key": {
+                        "type": "tendermint/PubKeyEd25519",
+                        "value": "GQEC/HB4sDBAVhHtUzyv4yct9ZGnudaP209QQBSTfSQ="
+                    },
+                    "voting_power": "50",
+                    "proposer_priority": null
+                }
+            ]
+        },
+        "provider": "BADFADAD0BEFEEDC0C0ADEADBEEFC0FFEEFACADE"
+    }, null, 2),
+    language: 'json',
+    minimap: { enabled: false }
+});
+
+document.getElementById('verify-btn').addEventListener('click', function() {
+    let untrusted = JSON.parse(untrustedBlockEditor.getValue());
+    let trusted = JSON.parse(trustedBlockEditor.getValue());
+    let trustThreshold = document.getElementById('trust-threshold-input').value;
+    let trustThresholdParts = trustThreshold.split("/");
+    if (trustThresholdParts.length !== 2) {
+        window.alert("Expected trust threshold to be of the format \"numerator/denominator\"");
+        return;
+    }
+    let trustThresholdNum = parseInt(trustThresholdParts[0].trim(), 10);
+    let trustThresholdDen = parseInt(trustThresholdParts[1].trim(), 10);
+    let trustingPeriod = parseInt(document.getElementById('trusting-period-input').value, 10);
+    let clockDrift = parseInt(document.getElementById('clock-drift-input').value, 10);
+    let now = document.getElementById('now-input').value;
+
+    let options = {
+        trust_threshold: [trustThresholdNum, trustThresholdDen],
+        trusting_period: trustingPeriod,
+        clock_drift: clockDrift
+    };
+
+    console.log("Untrusted block:", untrusted);
+    console.log("Trusted block:", trusted);
+    console.log("Options:", options);
+    console.log("Now:", now);
+
+    let verdict = LightClient.verify(untrusted, trusted, options, now);
+
+    document.getElementById('verdict').innerText = JSON.stringify(verdict, null, 2);
+    document.getElementById('verdict-section').style.visibility = 'visible';
+});
diff --git a/light-client-js/examples/verifier-web/package.json b/light-client-js/examples/verifier-web/package.json
new file mode 100644
index 000000000..ee22aae9b
--- /dev/null
+++ b/light-client-js/examples/verifier-web/package.json
@@ -0,0 +1,46 @@
+{
+  "name": "tendermint-light-client-verifier-web",
+  "version": "0.1.0",
+  "description": "an example app to demonstrate Tendermint Light Client verification on the web using WASM",
+  "main": "index.js",
+  "scripts": {
+    "build": "webpack --config webpack.config.js",
+    "start": "webpack-dev-server"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/informalsystems/tendermint-rs.git"
+  },
+  "keywords": [
+    "tendermint",
+    "light-client",
+    "webassembly",
+    "wasm",
+    "rust",
+    "webpack"
+  ],
+  "author": "Informal Systems ",
+  "contributors": [
+    "Romain Ruetschi ",
+    "Thane Thomson "
+  ],
+  "license": "(MIT OR Apache-2.0)",
+  "bugs": {
+    "url": "https://github.com/informalsystems/tendermint-rs/issues"
+  },
+  "homepage": "https://github.com/informalsystems/tendermint-rs",
+  "devDependencies": {
+    "copy-webpack-plugin": "^5.1.2",
+    "css-loader": "^5.0.2",
+    "file-loader": "^6.2.0",
+    "monaco-editor-webpack-plugin": "^3.0.0",
+    "style-loader": "^2.0.0",
+    "webpack": "^4.46.0",
+    "webpack-cli": "^3.3.12",
+    "webpack-dev-server": "^3.11.2"
+  },
+  "dependencies": {
+    "monaco-editor": "^0.22.3",
+    "tendermint-light-client-js": "file:../../pkg"
+  }
+}
diff --git a/light-client-js/examples/verifier-web/screenshot1.png b/light-client-js/examples/verifier-web/screenshot1.png
new file mode 100644
index 000000000..7aebf15cd
Binary files /dev/null and b/light-client-js/examples/verifier-web/screenshot1.png differ
diff --git a/light-client-js/examples/verifier-web/screenshot2.png b/light-client-js/examples/verifier-web/screenshot2.png
new file mode 100644
index 000000000..46000b865
Binary files /dev/null and b/light-client-js/examples/verifier-web/screenshot2.png differ
diff --git a/light-client-js/examples/verifier-web/webpack.config.js b/light-client-js/examples/verifier-web/webpack.config.js
new file mode 100644
index 000000000..09a1447a9
--- /dev/null
+++ b/light-client-js/examples/verifier-web/webpack.config.js
@@ -0,0 +1,27 @@
+const CopyWebpackPlugin = require("copy-webpack-plugin");
+const MonacoWebpackPlugin = require('monaco-editor-webpack-plugin');
+const path = require('path');
+
+module.exports = {
+  entry: "./bootstrap.js",
+  output: {
+    path: path.resolve(__dirname, "dist"),
+    filename: "bootstrap.js",
+  },
+  module: {
+    rules: [{
+      test: /\.css$/,
+      use: ['style-loader', 'css-loader']
+    }, {
+      test: /\.ttf$/,
+      use: ['file-loader']
+    }]
+  },
+  mode: "development",
+  plugins: [
+    new CopyWebpackPlugin(['index.html']),
+    new MonacoWebpackPlugin({
+      languages: ["json"]
+    })
+  ],
+};
diff --git a/light-client-js/src/lib.rs b/light-client-js/src/lib.rs
new file mode 100644
index 000000000..ea5245e67
--- /dev/null
+++ b/light-client-js/src/lib.rs
@@ -0,0 +1,88 @@
+mod utils;
+
+use serde::{Deserialize, Serialize};
+use std::time::Duration;
+use tendermint::Time;
+use tendermint_light_client::components::verifier::{ProdVerifier, Verifier};
+use tendermint_light_client::light_client::Options;
+use tendermint_light_client::types::{LightBlock, TrustThreshold};
+use wasm_bindgen::prelude::*;
+use wasm_bindgen::JsValue;
+
+// When the `wee_alloc` feature is enabled, use `wee_alloc` as the global
+// allocator.
+#[cfg(feature = "wee_alloc")]
+#[global_allocator]
+static ALLOC: wee_alloc::WeeAlloc = wee_alloc::WeeAlloc::INIT;
+
+/// Check whether a given untrusted block can be trusted.
+#[wasm_bindgen]
+pub fn verify(untrusted: &JsValue, trusted: &JsValue, options: &JsValue, now: &JsValue) -> JsValue {
+    let result = deserialize_params(untrusted, trusted, options, now).map(
+        |(untrusted, trusted, options, now)| {
+            let verifier = ProdVerifier::default();
+            verifier.verify(&untrusted, &trusted, &options, now)
+        },
+    );
+    JsValue::from_serde(&result).unwrap()
+}
+
+fn deserialize_params(
+    untrusted: &JsValue,
+    trusted: &JsValue,
+    options: &JsValue,
+    now: &JsValue,
+) -> Result<(LightBlock, LightBlock, Options, Time), Error> {
+    let untrusted = untrusted.into_serde().map_err(|e| Error::Serialization {
+        param: "untrusted".to_string(),
+        msg: e.to_string(),
+    })?;
+
+    let trusted = trusted.into_serde().map_err(|e| Error::Serialization {
+        param: "trusted".to_string(),
+        msg: e.to_string(),
+    })?;
+
+    let options = options
+        .into_serde::()
+        .map(Into::into)
+        .map_err(|e| Error::Serialization {
+            param: "options".to_string(),
+            msg: e.to_string(),
+        })?;
+
+    let now = now.into_serde().map_err(|e| Error::Serialization {
+        param: "now".to_string(),
+        msg: e.to_string(),
+    })?;
+
+    Ok((untrusted, trusted, options, now))
+}
+
+/// Errors produced by this crate.
+#[derive(Serialize, Deserialize, Debug)]
+#[serde(tag = "type")]
+pub enum Error {
+    /// A serialization/deserialization error occurred.
+    #[serde(rename = "serialization")]
+    Serialization { param: String, msg: String },
+}
+
+// Simplified options supplied from JavaScript.
+#[derive(Debug, Serialize, Deserialize)]
+pub struct JsOptions {
+    pub trust_threshold: (u64, u64),
+    pub trusting_period: u64,
+    pub clock_drift: u64,
+}
+
+impl From for Options {
+    fn from(o: JsOptions) -> Self {
+        let (num, den) = o.trust_threshold;
+        Self {
+            trust_threshold: TrustThreshold::new(num, den).unwrap(),
+            trusting_period: Duration::from_secs(o.trusting_period),
+            clock_drift: Duration::from_secs(o.clock_drift),
+        }
+    }
+}
diff --git a/light-client-js/src/utils.rs b/light-client-js/src/utils.rs
new file mode 100644
index 000000000..c4be847ee
--- /dev/null
+++ b/light-client-js/src/utils.rs
@@ -0,0 +1,11 @@
+#[allow(dead_code)]
+pub fn set_panic_hook() {
+    // When the `console_error_panic_hook` feature is enabled, we can call the
+    // `set_panic_hook` function at least once during initialization, and then
+    // we will get better error messages if our code ever panics.
+    //
+    // For more details see
+    // https://github.com/rustwasm/console_error_panic_hook#readme
+    #[cfg(feature = "console_error_panic_hook")]
+    console_error_panic_hook::set_once();
+}
diff --git a/light-client-js/tests/web.rs b/light-client-js/tests/web.rs
new file mode 100644
index 000000000..03e36c753
--- /dev/null
+++ b/light-client-js/tests/web.rs
@@ -0,0 +1,209 @@
+//! Test suite for the Web and headless browsers.
+
+#![cfg(target_arch = "wasm32")]
+
+extern crate wasm_bindgen_test;
+use tendermint::Time;
+use tendermint_light_client::components::verifier::Verdict;
+use tendermint_light_client::types::LightBlock;
+use tendermint_light_client_js::{verify, Error, JsOptions};
+use wasm_bindgen::JsValue;
+use wasm_bindgen_test::*;
+
+wasm_bindgen_test_configure!(run_in_browser);
+
+const UNTRUSTED_BLOCK: &str = r#"{
+    "signed_header": {
+        "header": {
+            "version": {
+                "block": "11",
+                "app": "0"
+            },
+            "chain_id": "test-chain",
+            "height": "4",
+            "time": "1970-01-01T00:00:04Z",
+            "last_block_id": null,
+            "last_commit_hash": null,
+            "data_hash": null,
+            "validators_hash": "75E6DD63C2DC2B58FE0ED82792EAB369C4308C7EC16B69446382CC4B41D46068",
+            "next_validators_hash": "C8CFFADA9808F685C4111693E1ADFDDBBEE9B9493493BEF805419F143C5B0D0A",
+            "consensus_hash": "75E6DD63C2DC2B58FE0ED82792EAB369C4308C7EC16B69446382CC4B41D46068",
+            "app_hash": "",
+            "last_results_hash": null,
+            "evidence_hash": null,
+            "proposer_address": "6AE5C701F508EB5B63343858E068C5843F28105F"
+        },
+        "commit": {
+            "height": "4",
+            "round": 1,
+            "block_id": {
+                "hash": "D0E7B0C678E290DA835BB26EE826472D66B6A306801E5FE0803C5320C554610A",
+                "part_set_header": {
+                    "total": 1,
+                    "hash": "D0E7B0C678E290DA835BB26EE826472D66B6A306801E5FE0803C5320C554610A"
+                }
+            },
+            "signatures": [
+                {
+                    "block_id_flag": 2,
+                    "validator_address": "6AE5C701F508EB5B63343858E068C5843F28105F",
+                    "timestamp": "1970-01-01T00:00:04Z",
+                    "signature": "lTGBsjVI6YwIRcxQ6Lct4Q+xrtJc9h3648c42uWe4MpSgy4rUI5g71AEpG90Tbn0PRizjKgCPhokPpQoQLiqAg=="
+                }
+            ]
+        }
+    },
+    "validator_set": {
+        "total_voting_power": "0",
+        "validators": [
+            {
+                "address": "6AE5C701F508EB5B63343858E068C5843F28105F",
+                "pub_key": {
+                    "type": "tendermint/PubKeyEd25519",
+                    "value": "GQEC/HB4sDBAVhHtUzyv4yct9ZGnudaP209QQBSTfSQ="
+                },
+                "voting_power": "50",
+                "proposer_priority": null
+            }
+        ]
+    },
+    "next_validator_set": {
+        "total_voting_power": "0",
+        "validators": [
+            {
+                "address": "C479DB6F37AB9757035CFBE10B687E27668EE7DF",
+                "pub_key": {
+                    "type": "tendermint/PubKeyEd25519",
+                    "value": "3wf60CidQcsIO7TksXzEZsJefMUFF73k6nP1YeEo9to="
+                },
+                "voting_power": "50",
+                "proposer_priority": null
+            }
+        ]
+    },
+    "provider": "BADFADAD0BEFEEDC0C0ADEADBEEFC0FFEEFACADE"
+}"#;
+
+const TRUSTED_BLOCK: &str = r#"{
+    "signed_header": {
+        "header": {
+            "version": {
+                "block": "11",
+                "app": "0"
+            },
+            "chain_id": "test-chain",
+            "height": "3",
+            "time": "1970-01-01T00:00:03Z",
+            "last_block_id": null,
+            "last_commit_hash": null,
+            "data_hash": null,
+            "validators_hash": "75E6DD63C2DC2B58FE0ED82792EAB369C4308C7EC16B69446382CC4B41D46068",
+            "next_validators_hash": "75E6DD63C2DC2B58FE0ED82792EAB369C4308C7EC16B69446382CC4B41D46068",
+            "consensus_hash": "75E6DD63C2DC2B58FE0ED82792EAB369C4308C7EC16B69446382CC4B41D46068",
+            "app_hash": "",
+            "last_results_hash": null,
+            "evidence_hash": null,
+            "proposer_address": "6AE5C701F508EB5B63343858E068C5843F28105F"
+        },
+        "commit": {
+            "height": "3",
+            "round": 1,
+            "block_id": {
+                "hash": "AAB1B09D5FADAAE7CDF3451961A63F810DB73BF3214A7B74DBA36C52EDF1A793",
+                "part_set_header": {
+                    "total": 1,
+                    "hash": "AAB1B09D5FADAAE7CDF3451961A63F810DB73BF3214A7B74DBA36C52EDF1A793"
+                }
+            },
+            "signatures": [
+                {
+                    "block_id_flag": 2,
+                    "validator_address": "6AE5C701F508EB5B63343858E068C5843F28105F",
+                    "timestamp": "1970-01-01T00:00:03Z",
+                    "signature": "xn0eSsHYIsqUbmfAiJq1R0hqZbfuIjs5Na1c88EC1iPTuQAesKg9I7nXG4pk8d6U5fU4GysNLk5I4f7aoefOBA=="
+                }
+            ]
+        }
+    },
+    "validator_set": {
+        "total_voting_power": "0",
+        "validators": [
+            {
+                "address": "6AE5C701F508EB5B63343858E068C5843F28105F",
+                "pub_key": {
+                    "type": "tendermint/PubKeyEd25519",
+                    "value": "GQEC/HB4sDBAVhHtUzyv4yct9ZGnudaP209QQBSTfSQ="
+                },
+                "voting_power": "50",
+                "proposer_priority": null
+            }
+        ]
+    },
+    "next_validator_set": {
+        "total_voting_power": "0",
+        "validators": [
+            {
+                "address": "6AE5C701F508EB5B63343858E068C5843F28105F",
+                "pub_key": {
+                    "type": "tendermint/PubKeyEd25519",
+                    "value": "GQEC/HB4sDBAVhHtUzyv4yct9ZGnudaP209QQBSTfSQ="
+                },
+                "voting_power": "50",
+                "proposer_priority": null
+            }
+        ]
+    },
+    "provider": "BADFADAD0BEFEEDC0C0ADEADBEEFC0FFEEFACADE"
+}"#;
+
+#[wasm_bindgen_test]
+fn successful_verification() {
+    let (untrusted_block, trusted_block) = test_blocks();
+    let options = test_options();
+    // Choose a "now" value within the trusting period
+    let now =
+        JsValue::from_serde(&Time::parse_from_rfc3339("1970-01-07T00:00:00Z").unwrap()).unwrap();
+    let js_result = verify(&untrusted_block, &trusted_block, &options, &now);
+    console_log!("js_result = {:?}", js_result);
+    let verdict = JsValue::into_serde::>(&js_result)
+        .unwrap()
+        .unwrap();
+    assert_eq!(verdict, Verdict::Success);
+}
+
+#[wasm_bindgen_test]
+fn failed_verification_outside_trusting_period() {
+    let (untrusted_block, trusted_block) = test_blocks();
+    let options = test_options();
+    // Choose a "now" value outside the trusting period
+    let now =
+        JsValue::from_serde(&Time::parse_from_rfc3339("1970-01-16T00:00:00Z").unwrap()).unwrap();
+    let js_result = verify(&untrusted_block, &trusted_block, &options, &now);
+    console_log!("js_result = {:?}", js_result);
+    // The result is Ok because we successfully obtained a verdict, even if the
+    // verdict isn't Verdict::Success.
+    let verdict = JsValue::into_serde::>(&js_result)
+        .unwrap()
+        .unwrap();
+    match verdict {
+        Verdict::Success | Verdict::NotEnoughTrust(_) => panic!("unexpected verdict"),
+        _ => {}
+    }
+}
+
+fn test_blocks() -> (JsValue, JsValue) {
+    let untrusted_block =
+        JsValue::from_serde(&serde_json::from_str::(UNTRUSTED_BLOCK).unwrap()).unwrap();
+    let trusted_block =
+        JsValue::from_serde(&serde_json::from_str::(TRUSTED_BLOCK).unwrap()).unwrap();
+    (untrusted_block, trusted_block)
+}
+
+fn test_options() -> JsValue {
+    JsValue::from_serde(&JsOptions {
+        trust_threshold: (1, 3),
+        trusting_period: 1209600, // 2 weeks
+        clock_drift: 5,           // 5 seconds
+    })
+    .unwrap()
+}
diff --git a/light-client/src/components/verifier.rs b/light-client/src/components/verifier.rs
index b25177dac..fb37b1c81 100644
--- a/light-client/src/components/verifier.rs
+++ b/light-client/src/components/verifier.rs
@@ -11,10 +11,11 @@ use crate::{
     types::{LightBlock, Time},
 };
 use preds::{errors::VerificationError, ProdPredicates, VerificationPredicates};
+use serde::{Deserialize, Serialize};
 
 /// Represents the result of the verification performed by the
 /// verifier component.
-#[derive(Debug)]
+#[derive(Debug, Serialize, Deserialize, PartialEq, Eq)]
 pub enum Verdict {
     /// Verification succeeded, the block is valid.
     Success,
diff --git a/light-client/src/operations/voting_power.rs b/light-client/src/operations/voting_power.rs
index 2bcd40955..1e46d1b5f 100644
--- a/light-client/src/operations/voting_power.rs
+++ b/light-client/src/operations/voting_power.rs
@@ -16,7 +16,7 @@ use tendermint::trust_threshold::TrustThreshold as _;
 use tendermint::vote::{SignedVote, ValidatorIndex, Vote};
 
 /// Tally for the voting power computed by the `VotingPowerCalculator`
-#[derive(Copy, Clone, Debug, PartialEq, Serialize, Deserialize)]
+#[derive(Copy, Clone, Debug, PartialEq, Serialize, Deserialize, Eq)]
 pub struct VotingPowerTally {
     /// Total voting power
     pub total: u64,
diff --git a/light-client/src/predicates/errors.rs b/light-client/src/predicates/errors.rs
index 569f3d157..99c02fb34 100644
--- a/light-client/src/predicates/errors.rs
+++ b/light-client/src/predicates/errors.rs
@@ -10,7 +10,7 @@ use crate::types::{Hash, Height, Time, Validator, ValidatorAddress};
 
 /// The various errors which can be raised by the verifier component,
 /// when validating or verifying a light block.
-#[derive(Debug, Clone, Error, PartialEq, Serialize, Deserialize)]
+#[derive(Debug, Clone, Error, PartialEq, Serialize, Deserialize, Eq)]
 pub enum VerificationError {
     /// The header is from the future
     #[error("header from the future: header_time={header_time} now={now}")]
diff --git a/tendermint/src/validator.rs b/tendermint/src/validator.rs
index 9201ccdf8..62bc04a6a 100644
--- a/tendermint/src/validator.rs
+++ b/tendermint/src/validator.rs
@@ -143,7 +143,7 @@ impl Set {
 
 /// Validator information
 // Todo: Remove address and make it into a function that generates it on the fly from pub_key.
-#[derive(Clone, Copy, Debug, PartialEq, Serialize, Deserialize)]
+#[derive(Clone, Copy, Debug, PartialEq, Serialize, Deserialize, Eq)]
 pub struct Info {
     /// Validator account address
     pub address: account::Id,