Add feig payment terminal code (#15)

* Add feig payment terminal code

* fix test

* fix

* update metadat

* change dep

* Add README

---------

Co-authored-by: Dima Dorezyuk <[email protected]>

Cargo.toml

@@ -5,6 +5,7 @@ members = [
    "zvt_builder",
    "zvt_cli", 
    "zvt_derive",
+   "zvt_feig_terminal",
 ]
 
 [workspace.package]

WORKSPACE

@@ -24,6 +24,7 @@ crates_repository(
         "//zvt_builder:Cargo.toml",
         "//zvt_cli:Cargo.toml",
         "//zvt_derive:Cargo.toml",
+        "//zvt_feig_terminal:Cargo.toml",
     ],
 )
 

zvt_feig_terminal/BUILD.bazel

@@ -0,0 +1,17 @@
+load("@rules_rust//rust:defs.bzl", "rust_binary", "rust_library", "rust_test")
+load("@crate_index//:defs.bzl", "all_crate_deps")
+
+rust_library(
+    name = "zvt_feig_terminal",
+    srcs = glob(["src/*.rs"]),
+    deps = all_crate_deps() + ["//zvt"],
+    proc_macro_deps = all_crate_deps(proc_macro = True),
+    edition = "2021",
+    visibility = ["//visibility:public"],
+)
+
+rust_test(
+    name = "zvt_feig_terminal_test",
+    deps = all_crate_deps(normal_dev = True),
+    crate = ":zvt_feig_terminal",
+)

zvt_feig_terminal/Cargo.toml

@@ -0,0 +1,31 @@
+[package]
+name = "zvt_feig_terminal"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+zvt = { version = "0.1.0", path = "../zvt" }
+anyhow = "1.0.75"
+tokio = { version = "1.32.0", features = ["macros", "rt-multi-thread", "net", "sync"] }
+log = "0.4.20"
+trust-dns-client = "0.23.0"
+trust-dns-proto = "0.23.0"
+async-trait = "0.1.73"
+env_logger = "0.10.0"
+tonic = "0.8.3"
+tokio-stream = "0.1.14"
+serde = { version = "1.0.188", features = ["derive"] }
+thiserror = "1.0.48"
+time = { version = "0.3.28", features = ["macros"] }
+time-macros = "0.2.14"
+pin-project = "1.1.3"
+futures = "0.3.28"
+async-stream = "0.3.5"
+mockall = "0.11.4"
+mockall_double = "0.3.0"
+num-traits = "0.2.17"
+
+[dev-dependencies]
+serde_json = "1.0.105"

zvt_feig_terminal/README.md

@@ -0,0 +1,9 @@
+# ZVT Feig Terminal
+
+The crate implements the application logic for using a Feig terminal in production.
+
+We assume that you interact with the Feig terminal over TCP/IP.
+
+The high level interface for interacting with the Feig terminal is implemented
+in [src/feig.rs](src/feig.rs). It provides good defaults for reading cards and
+allows you to begin, commit or cancel transactions.

zvt_feig_terminal/src/config.rs

@@ -0,0 +1,137 @@
+use anyhow::{bail, Result};
+use serde::Deserialize;
+use std::net::Ipv4Addr;
+
+/// The config for the Feig terminal included in the
+/// [PoleConfiguration::configuration].
+#[derive(serde::Deserialize, PartialEq, Debug, Clone)]
+pub struct FeigConfig {
+    /// The currency code as defined by ISO 4217. See
+    /// https://en.wikipedia.org/wiki/ISO_4217.
+    ///
+    /// The input is the string representation of the currency as defined by
+    /// ISO 4217, e.x. `EUR` or `GBP`.
+    #[serde(default = "currency")]
+    #[serde(deserialize_with = "deserialize_iso_4217")]
+    pub currency: usize,
+
+    /// The pre-authorization amount in the smallest currency unit (e.x. Cent).
+    #[serde(default = "pre_authorization_amount")]
+    pub pre_authorization_amount: usize,
+
+    /// The default time to wait for reading a card in seconds. While a card is being read, the
+    /// payment terminal cannot do anything else (like refunding a transaction for example).
+    #[serde(default = "read_card_timeout")]
+    pub read_card_timeout: u8,
+
+    /// The password to the payment terminal.
+    #[serde(default)]
+    pub password: usize,
+}
+
+/// Deserializer which consumes a string code and returns the numerical code.
+fn deserialize_iso_4217<'de, D>(deserializer: D) -> std::result::Result<usize, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    let code = String::deserialize(deserializer)?;
+    iso_4217(&code).map_err(serde::de::Error::custom)
+}
+
+/// The default currency (returns the EUR code).
+const fn currency() -> usize {
+    978
+}
+
+/// The default read card timeout in seconds
+const fn read_card_timeout() -> u8 {
+    15
+}
+
+/// The default pre-authorization amount in Cent (returns 25 EUR).
+const fn pre_authorization_amount() -> usize {
+    2500
+}
+
+impl Default for FeigConfig {
+    fn default() -> Self {
+        Self {
+            currency: currency(),
+            pre_authorization_amount: pre_authorization_amount(),
+            read_card_timeout: read_card_timeout(),
+            password: 0,
+        }
+    }
+}
+
+/// Maps the currency code (three letters) to a numeric value.
+///
+/// The mapping is defined under the ISO 4217. See
+/// https://en.wikipedia.org/wiki/ISO_4217
+fn iso_4217(code: &str) -> Result<usize> {
+    match code.to_uppercase().as_str() {
+        // Keep the list sorted by the numeric value.
+        "SEK" => Ok(752),
+        "GBP" => Ok(826),
+        "EUR" => Ok(978),
+        _ => bail!("Unknown currency code {code}"),
+    }
+}
+
+/// The configuration needed for the entire payment terminal, which contains
+/// parsed data.
+#[derive(Clone, Debug)]
+pub struct Config {
+    pub terminal_id: String,
+    /// We only use feig_serial to make sure we are connected to the proper
+    /// terminal.
+    pub feig_serial: String,
+    pub ip_address: Ipv4Addr,
+    /// Parsed from [PoleConfiguration::configuration].
+    pub feig_config: FeigConfig,
+    /// Maximum number of concurrent transactions.
+    pub transactions_max_num: usize,
+}
+
+impl Default for Config {
+    fn default() -> Self {
+        Self {
+            terminal_id: String::default(),
+            feig_serial: String::default(),
+            ip_address: Ipv4Addr::new(0, 0, 0, 0),
+            feig_config: FeigConfig::default(),
+            transactions_max_num: 1,
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+
+    use super::*;
+
+    #[test]
+    fn test_feig_config() {
+        // Valid inputs.
+        let empty = serde_json::from_str::<FeigConfig>("{}").unwrap();
+        assert_eq!(empty, FeigConfig::default());
+
+        let with_currency = serde_json::from_str::<FeigConfig>("{\"currency\": \"GBP\"}").unwrap();
+        assert_eq!(with_currency.currency, 826);
+        assert_eq!(with_currency.pre_authorization_amount, 2500);
+
+        let with_all = serde_json::from_str::<FeigConfig>(
+            "{\"currency\": \"GBP\", \"pre_authorization_amount\": 10}",
+        )
+        .unwrap();
+        assert_eq!(with_all.currency, 826);
+        assert_eq!(with_all.pre_authorization_amount, 10);
+
+        // Invalid inputs.
+        assert!(serde_json::from_str::<FeigConfig>("{\"currency\": \"ABC\"}").is_err());
+        assert!(serde_json::from_str::<FeigConfig>("{\"currency\": 123}").is_err());
+        assert!(
+            serde_json::from_str::<FeigConfig>("{\"pre_authorization_amount\": \"AB\"}").is_err()
+        );
+    }
+}