canic_host/icp/
balance.rs

1//! Module: icp::balance
2//!
3//! Responsibility: observe the selected identity's default ICP and cycles accounts.
4//! Does not own: funding sufficiency policy, Fleet authority, or deployment planning.
5//! Boundary: parses the exact machine-readable balance output owned by ICP CLI.
6
7use super::{error::IcpCommandError, model::IcpCli, run::run_json};
8
9use serde::Deserialize;
10use thiserror::Error as ThisError;
11
12///
13/// IcpBalanceError
14///
15/// Typed failure while observing an identity ledger balance through ICP CLI.
16///
17#[derive(Debug, ThisError)]
18pub enum IcpBalanceError {
19    #[error("ICP CLI returned an invalid {unit} balance: {value}")]
20    InvalidAmount { unit: &'static str, value: String },
21
22    #[error("ICP balance does not fit e8s: {value}")]
23    IcpAmountOverflow { value: String },
24
25    #[error(transparent)]
26    Icp(#[from] IcpCommandError),
27}
28
29#[derive(Deserialize)]
30#[serde(deny_unknown_fields)]
31struct BalanceOutput {
32    balance: String,
33}
34
35impl IcpCli {
36    /// Observe the selected identity's default Cycles Ledger account.
37    pub fn identity_cycles_balance(&self) -> Result<u128, IcpBalanceError> {
38        let mut command = self.command();
39        command.args(["cycles", "balance", "--json"]);
40        self.add_target_args(&mut command);
41        let output = run_json::<BalanceOutput>(&mut command)?;
42        parse_cycles(&output.balance)
43    }
44
45    /// Observe the selected identity's default ICP Ledger account in e8s.
46    pub fn identity_icp_balance_e8s(&self) -> Result<u64, IcpBalanceError> {
47        let mut command = self.command();
48        command.args(["token", "balance", "--json"]);
49        self.add_target_args(&mut command);
50        let output = run_json::<BalanceOutput>(&mut command)?;
51        parse_icp_e8s(&output.balance)
52    }
53}
54
55fn parse_cycles(value: &str) -> Result<u128, IcpBalanceError> {
56    let amount = strip_unit(value, "cycles")?;
57    amount
58        .replace('_', "")
59        .parse()
60        .map_err(|_| invalid_amount("cycles", value))
61}
62
63fn parse_icp_e8s(value: &str) -> Result<u64, IcpBalanceError> {
64    const E8S_PER_ICP: u64 = 100_000_000;
65
66    let amount = strip_unit(value, "ICP")?.replace('_', "");
67    let mut parts = amount.split('.');
68    let whole = parts
69        .next()
70        .filter(|whole| !whole.is_empty())
71        .and_then(|whole| whole.parse::<u64>().ok())
72        .ok_or_else(|| invalid_amount("ICP", value))?;
73    let fraction = parts.next().unwrap_or_default();
74    if parts.next().is_some()
75        || fraction.len() > 8
76        || !fraction.bytes().all(|byte| byte.is_ascii_digit())
77    {
78        return Err(invalid_amount("ICP", value));
79    }
80    let fractional_e8s = if fraction.is_empty() {
81        0
82    } else {
83        let padding =
84            u32::try_from(8_usize - fraction.len()).map_err(|_| invalid_amount("ICP", value))?;
85        fraction
86            .parse::<u64>()
87            .map_err(|_| invalid_amount("ICP", value))?
88            .checked_mul(10_u64.pow(padding))
89            .ok_or_else(|| IcpBalanceError::IcpAmountOverflow {
90                value: value.to_string(),
91            })?
92    };
93    whole
94        .checked_mul(E8S_PER_ICP)
95        .and_then(|whole_e8s| whole_e8s.checked_add(fractional_e8s))
96        .ok_or_else(|| IcpBalanceError::IcpAmountOverflow {
97            value: value.to_string(),
98        })
99}
100
101fn strip_unit<'a>(value: &'a str, unit: &'static str) -> Result<&'a str, IcpBalanceError> {
102    value
103        .trim()
104        .strip_suffix(unit)
105        .map(str::trim)
106        .filter(|amount| !amount.is_empty())
107        .ok_or_else(|| invalid_amount(unit, value))
108}
109
110fn invalid_amount(unit: &'static str, value: &str) -> IcpBalanceError {
111    IcpBalanceError::InvalidAmount {
112        unit,
113        value: value.to_string(),
114    }
115}
116
117// -----------------------------------------------------------------------------
118// Tests
119
120#[cfg(test)]
121mod tests {
122    use super::*;
123
124    const ICP_CLI_1_3_CYCLES_BALANCE_JSON: &str = r#"{"balance":"3_519_900_000_000 cycles"}"#;
125    const ICP_CLI_1_3_TOKEN_BALANCE_JSON: &str = r#"{"balance":"1.23456780 ICP"}"#;
126
127    #[test]
128    fn decodes_icp_cli_one_three_balance_json_goldens() {
129        let cycles: BalanceOutput = serde_json::from_str(ICP_CLI_1_3_CYCLES_BALANCE_JSON)
130            .expect("ICP CLI 1.3 cycles balance JSON");
131        let token: BalanceOutput = serde_json::from_str(ICP_CLI_1_3_TOKEN_BALANCE_JSON)
132            .expect("ICP CLI 1.3 token balance JSON");
133
134        assert_eq!(parse_cycles(&cycles.balance).unwrap(), 3_519_900_000_000);
135        assert_eq!(parse_icp_e8s(&token.balance).unwrap(), 123_456_780);
136    }
137
138    #[test]
139    fn parses_exact_cycles_ledger_amounts() {
140        assert_eq!(
141            parse_cycles("3_519_900_000_000 cycles").unwrap(),
142            3_519_900_000_000
143        );
144        assert_eq!(parse_cycles("0 cycles").unwrap(), 0);
145        assert!(matches!(
146            parse_cycles("1.5 cycles"),
147            Err(IcpBalanceError::InvalidAmount { unit: "cycles", .. })
148        ));
149    }
150
151    #[test]
152    fn parses_exact_icp_amounts_into_e8s() {
153        assert_eq!(parse_icp_e8s("1.23456780 ICP").unwrap(), 123_456_780);
154        assert_eq!(parse_icp_e8s("1 ICP").unwrap(), 100_000_000);
155        assert_eq!(parse_icp_e8s("0.1 ICP").unwrap(), 10_000_000);
156        assert!(matches!(
157            parse_icp_e8s("0.000000001 ICP"),
158            Err(IcpBalanceError::InvalidAmount { unit: "ICP", .. })
159        ));
160    }
161}
canic_host/icp/balance.rs

canic_host/icp/
balance.rs
