Fedimint Kotlin Wrapper

README.md

@@ -6,26 +6,37 @@ This project is intended to be an easy-to-use starting point for those intereste
 
 ## Getting Started
 
-You can install the cli app with `cargo install fedimint-clientd` or by cloning the repo and running `cargo build --release` in the root directory.
-
-`fedimint-clientd` runs from the command line and takes a few arguments, which are also available as environment variables. Fedimint uses rocksDB, an embedded key-value store, to store its state. The `--fm_db_path` argument is required and should be an absolute path to a directory where the database will be stored.
-
-```
-CLI USAGE:
-fedimint-clientd \
-  --db-path=/absolute/path/to/dir/to/store/database \
-  --password="some-secure-password-that-becomes-the-bearer-token" \
-  --addr="127.0.0.1:8080"
-  --mode="rest"
-  --invite-code="fed1-fedimint-invite-code"
-
-ENV USAGE:
-FEDIMINT_CLIENTD_DB_PATH=/absolute/path/to/dir/to/store/database
-FEDIMINT_CLIENTD_PASSWORD="some-secure-password-that-becomes-the-bearer-token"
-FEDIMINT_CLIENTD_ADDR="127.0.0.1:8080"
-FEDIMINT_CLIENTD_MODE="rest"
-FEDIMINT_CLIENTD_INVITE_CODE="fed1-fedimint-invite-code"
-```
+1. You can install the cli app with `cargo install fedimint-clientd` or by cloning the repo and running `cargo build --release` in the root directory.
+
+    `fedimint-clientd` runs from the command line and takes a few arguments, which are also available as environment variables. Fedimint uses rocksDB, an embedded key-value store, to store its state. The `--fm_db_path` argument is required and should be an absolute path to a directory where the database will be stored.
+
+    ```shell
+    CLI USAGE:
+    fedimint-clientd \
+      --db-path=/absolute/path/to/dir/to/store/database \
+      --password="some-secure-password-that-becomes-the-bearer-token" \
+      --addr="127.0.0.1:3333"
+      --mode="rest"
+      --invite-code="fed1-fedimint-invite-code"
+    ```
+
+2. With a Nix environment already setup:
+- Clone the repo and run `nix develop` to install and build the dependencies.
+- Run `just dev` to fire up the client app.
+
+  Make sure to configure your environment variables as shown below:
+
+  ```shell
+  ENV USAGE:
+  FEDIMINT_CLIENTD_DB_PATH=/absolute/path/to/dir/to/store/database
+  FEDIMINT_CLIENTD_PASSWORD="some-secure-password-that-becomes-the-bearer-token"
+  FEDIMINT_CLIENTD_ADDR="127.0.0.1:3333"
+  FEDIMINT_CLIENTD_BASE_URL="127.0.0.1:3333"
+  FEDIMINT_CLIENTD_MODE="rest"
+  # this is the invite code to the Fedi Alpha federation mutinynet,
+  # you can replace it with another but its the most useful one for testing so good to at least have it
+  FEDIMINT_CLIENTD_INVITE_CODE="fed11qgqrgvnhwden5te0v9k8q6rp9ekh2arfdeukuet595cr2ttpd3jhq6rzve6zuer9wchxvetyd938gcewvdhk6tcqqysptkuvknc7erjgf4em3zfh90kffqf9srujn6q53d6r056e4apze5cw27h75"
+  ```
 
 ## Fedimint Clientd Endpoints
 

flake.nix

@@ -103,7 +103,13 @@
         legacyPackages = outputs;
         packages = { default = outputs.fedimint-clientd; };
         devShells = flakeboxLib.mkShells {
-          packages = [ ];
+          packages = with pkgs; [
+            jdk21 # JDK 22 will be in $JAVA_HOME (and in javaToolchains)
+            jextract # jextract (Nix package) contains a jlinked executable and bundles its own JDK 22
+            (gradle.override { # Gradle 8.7 (Nix package) depends-on and directly uses JDK 21 to launch Gradle itself
+              javaToolchains = [ jdk21 ];
+            })
+          ];
           buildInputs = commonArgs.buildInputs;
           nativeBuildInputs = [
             pkgs.mprocs
@@ -120,6 +126,7 @@
             fedimint.packages.${system}.fedimint-pkgs
           ];
           shellHook = ''
+            export JAVA_HOME="${pkgs.jdk21}"
             export RUSTFLAGS="--cfg tokio_unstable"
             export RUSTDOCFLAGS="--cfg tokio_unstable"
             export RUST_LOG="info"

justfile.local.just

@@ -16,12 +16,16 @@ test-py-async:
 test-go:
   cd wrappers/fedimint-go && go run cmd/main.go
 
+test-kotlin:
+  cd wrappers/fedimint-kotlin && ./gradlew build && ./gradlew run
+
 test-all:
   set -e
   (just test-ts && echo "test-ts completed successfully") &
   (just test-py && echo "test-py completed successfully") &
   (just test-py-async && echo "test-py-async completed successfully") &
   (just test-go && echo "test-go completed successfully") &
+  (just test-kotlin && echo "test-kotlin completed successfully") &
   wait
 
 wscat:

wrappers/fedimint-kotlin/.gitignore

@@ -0,0 +1,36 @@
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/

wrappers/fedimint-kotlin/README.md

@@ -0,0 +1,34 @@
+
+# Fedimint SDK for Kotlin
+
+This is a Kotlin client that consumes the Fedimint Http Client (https://github.com/kodylow/fedimint-http-client)[https://github.com/kodylow/fedimint-http-client], communicating with it via HTTP and a password. It's a hacky prototype, but it works. All of the federation handling code happens in the fedimint-http-client, this just exposes a simple API for interacting with the client from Kotlin.
+
+Start the following in the fedimint-http-client .env environment variables:
+
+```bash
+FEDIMINT_CLIENTD_DB_PATH="YOUR-DATABASE-PATH"
+FEDIMINT_CLIENTD_PASSWORD="YOUR-PASSWORD"
+FEDIMINT_CLIENTD_ADDR="127.0.0.1:3333"
+FEDIMINT_CLIENTD_MODE="rest"
+FEDIMINT_CLIENTD_INVITE_CODE="fed11qgqrgvnhwden5te0v9k8q6rp9ekh2arfdeukuet595cr2ttpd3jhq6rzve6zuer9wchxvetyd938gcewvdhk6tcqqysptkuvknc7erjgf4em3zfh90kffqf9srujn6q53d6r056e4apze5cw27h75"
+FEDIMINT_CLIENTD_BASE_URL="127.0.0.1:3333"
+```
+
+Then start the fedimint-http-client server:
+
+```bash
+cargo run
+```
+
+Then you are ready to run the Kotlin client. You have 2 oprions to fire it up:
+
+1. Use an Intellij IDE or Android Studio.
+
+    This is the simplest and best way to work with the Kotlin wrapper. Open the Kotlin project with any Gradle based IDE such as Intellij or Android Studio.
+
+2. Run the following commands from the Kotlin project root folder.
+
+    ```bash
+    ./gradlew build
+    ./gradlew run
+    ```

wrappers/fedimint-kotlin/build.gradle.kts

@@ -0,0 +1,43 @@
+
+val ktor_version: String by project
+val kotlin_version: String by project
+val logback_version: String by project
+
+plugins {
+    kotlin("jvm") version "1.9.24"
+    id("io.ktor.plugin") version "2.3.10"
+    id("org.jetbrains.kotlin.plugin.serialization") version "1.9.24"
+}
+
+group = "com.fedimintClientd"
+version = "0.0.1"
+
+application {
+    mainClass.set("com.fedimintClientd.ApplicationKt")
+
+    val isDevelopment: Boolean = project.ext.has("development")
+    applicationDefaultJvmArgs = listOf("-Dio.ktor.development=$isDevelopment")
+}
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation("io.ktor:ktor-server-content-negotiation-jvm")
+    implementation("io.ktor:ktor-server-core-jvm")
+    implementation("io.ktor:ktor-serialization-kotlinx-json-jvm")
+    implementation("io.ktor:ktor-server-netty-jvm")
+    implementation("ch.qos.logback:logback-classic:$logback_version")
+    implementation("io.ktor:ktor-client-core:$ktor_version")
+    implementation("io.ktor:ktor-client-cio:$ktor_version")
+    implementation("io.ktor:ktor-client-auth:$ktor_version")
+    implementation("io.ktor:ktor-client-content-negotiation:$ktor_version")
+    implementation("io.ktor:ktor-client-logging:$ktor_version")
+    implementation("ch.qos.logback:logback-classic:$logback_version")
+    implementation("io.ktor:ktor-serialization-gson:$ktor_version")
+    implementation(kotlin("script-runtime"))
+    implementation ("io.github.cdimascio:dotenv-kotlin:6.4.1")
+    testImplementation("io.ktor:ktor-server-tests-jvm")
+    testImplementation("org.jetbrains.kotlin:kotlin-test-junit:$kotlin_version")
+}

wrappers/fedimint-kotlin/gradle.properties

@@ -0,0 +1,4 @@
+ktor_version=2.3.10
+kotlin_version=1.9.24
+logback_version=1.4.14
+kotlin.code.style=official

wrappers/fedimint-kotlin/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.4-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists