# Eric
[](https://crates.io/crates/eric-bindings)
[](https://docs.rs/eric-bindings)
[](https://crates.io/crates/eric-sdk)
[](https://docs.rs/eric-sdk)
[](https://github.com/quambene/eric-rs/actions/workflows/ci.yml)
Rust bindings and SDK for the ELSTER Rich Client (ERiC)
- [What is ELSTER?](#what-is-elster)
- [What is ERiC?](#what-is-eric)
- [Requirements](#requirements)
- [Rust bindings](#rust-bindings)
- [Generate bindings](#generate-bindings)
- [Test bindings](#test-bindings)
- [Eric SDK](#eric-sdk)
- [Usage](#usage)
- [Supported Eric versions](#supported-eric-versions)
- [Test SDK](#test-sdk)
- [Changelog](#changelog)
## What is ELSTER?
Elster (short for _Elektronische Steuererklärung_) is a project by the German tax administrations to process tax returns and declarations.
## What is ERiC?
ERiC is a shared C library that is integrated into a tax application. ERiC checks the data supplied by the tax application for plausibility, and transmits the data encrypted to the computing center of the respective tax administration.
## Requirements
You need to have the shared library `libericapi.so` and the header file `ericapi.h` available on your system which can be downloaded from [ELSTER for developers](https://www.elster.de/elsterweb/entwickler/login) after access has been requested [here](https://www.elster.de/elsterweb/registrierung-entwickler/form).
For generating the bindings on your platform and architecture, you need `libclang` as well. For example, on Debian/Ubuntu install:
``` bash
apt install llvm-dev libclang-dev clang
```
## Rust bindings
### Generate bindings
To generate the bindings, `eric-bindings` expects the environment variables `LIBRARY_NAME`, `LIBRARY_PATH`, `HEADER_FILE`, and
`PLUGIN_PATH`. For example:
``` bash
LIBRARY_NAME=ericapi
LIBRARY_PATH=ERiC-38.1.6.0-Linux-x86_64/ERiC-38.1.6.0/Linux-x86_64/lib
HEADER_FILE=ERiC-38.1.6.0-Linux-x86_64/ERiC-38.1.6.0/Linux-x86_64/include/ericapi.h
PLUGIN_PATH=ERiC-38.1.6.0-Linux-x86_64/ERiC-38.1.6.0/Linux-x86_64/lib/plugins2
```
The bindings have to be generated on-the-fly for your specific platform and architecture:
``` bash
cargo build -p eric-bindings
```
The bindings are generated in `target/debug/build/eric-bindings-<random-id>/out/bindings.rs`.
### Test bindings
The bindings are included in `src/lib.rs` via `include!` macro and tested by:
``` bash
cargo test -p eric-bindings --lib
```
Logs are written to `eric.log` in the current directory.
## Eric SDK
`eric-sdk` supports single-threaded Eric instances.
### Usage
To use `eric-sdk`, add the path of the shared C library (e.g. to `LD_LIBRARY_PATH` on Linux).
To send the xml file, the path and password of the Elster certificate has to be provided via environment variables `CERTIFICATE_PATH` and `CERTIFICATE_PASSWORD`.
### Supported Eric versions
| 0.1.0 | 38.1.6.0 |
### Test SDK
``` bash
# Run unit tests
cargo test -p eric-sdk -- --test-threads=1
# Run integration tests
cargo test -p eric-sdk --test '*' -- --test-threads=1
# Run external tests
cargo test -p eric-sdk --test '*' --features external-test -- --test-threads=1
```
## Changelog
The `eric-rs` repository contains multiple crates with separate changelogs:
- `eric-bindings`: [view changelog](https://github.com/quambene/eric-rs/blob/main/eric-bindings/CHANGELOG.md)
- `eric-sdk`: [view changelog](https://github.com/quambene/eric-rs/blob/main/eric-sdk/CHANGELOG.md)