[pbs-devel] [PATCH proxmox 1/3] add `proxmox-human-byte` crate

[Lukas Wagner <l.wagner@proxmox.com>]

The module previously lived in `pbs-api-types`, however turned out to
be useful in other places as well (POM, proxmox-notify), so it is moved
here as its own micro-crate.

Signed-off-by: Lukas Wagner <l.wagner@proxmox.com>
---
 Cargo.toml                              |   1 +
 proxmox-human-byte/Cargo.toml           |  15 +
 proxmox-human-byte/debian/changelog     |   5 +
 proxmox-human-byte/debian/control       |  43 +++
 proxmox-human-byte/debian/copyright     |  16 ++
 proxmox-human-byte/debian/debcargo.toml |   7 +
 proxmox-human-byte/src/lib.rs           | 358 ++++++++++++++++++++++++
 7 files changed, 445 insertions(+)
 create mode 100644 proxmox-human-byte/Cargo.toml
 create mode 100644 proxmox-human-byte/debian/changelog
 create mode 100644 proxmox-human-byte/debian/control
 create mode 100644 proxmox-human-byte/debian/copyright
 create mode 100644 proxmox-human-byte/debian/debcargo.toml
 create mode 100644 proxmox-human-byte/src/lib.rs

diff --git a/Cargo.toml b/Cargo.toml
index a32e1c6..ac2bd7e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,6 +6,7 @@ members = [
     "proxmox-borrow",
     "proxmox-compression",
     "proxmox-http",
+    "proxmox-human-byte",
     "proxmox-io",
     "proxmox-lang",
     "proxmox-ldap",
diff --git a/proxmox-human-byte/Cargo.toml b/proxmox-human-byte/Cargo.toml
new file mode 100644
index 0000000..4cdbe6c
--- /dev/null
+++ b/proxmox-human-byte/Cargo.toml
@@ -0,0 +1,15 @@
+[package]
+name = "proxmox-human-byte"
+version = "0.1.0"
+authors.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+exclude.workspace = true
+description = "Proxmox library for formatting byte sizes (IEC or SI)"
+
+[dependencies]
+anyhow.workspace = true
+proxmox-schema = { workspace = true, features = ["api-macro"]}
+proxmox-serde.workspace = true
+serde.workspace = true
diff --git a/proxmox-human-byte/debian/changelog b/proxmox-human-byte/debian/changelog
new file mode 100644
index 0000000..7f7603b
--- /dev/null
+++ b/proxmox-human-byte/debian/changelog
@@ -0,0 +1,5 @@
+rust-proxmox-human-byte (0.1.0-1) stable; urgency=medium
+
+  * Initial release.
+
+ --  Proxmox Support Team <support@proxmox.com>  Thu, 12 Jan 2023 11:42:11 +0200
diff --git a/proxmox-human-byte/debian/control b/proxmox-human-byte/debian/control
new file mode 100644
index 0000000..6aae2a5
--- /dev/null
+++ b/proxmox-human-byte/debian/control
@@ -0,0 +1,43 @@
+Source: rust-proxmox-human-byte
+Section: rust
+Priority: optional
+Build-Depends: debhelper (>= 12),
+ dh-cargo (>= 25),
+ cargo:native <!nocheck>,
+ rustc:native <!nocheck>,
+ libstd-rust-dev <!nocheck>,
+ librust-anyhow-1+default-dev <!nocheck>,
+ librust-proxmox-schema-1+api-macro-dev (>= 1.3.7-~~) <!nocheck>,
+ librust-proxmox-schema-1+default-dev (>= 1.3.7-~~) <!nocheck>,
+ librust-proxmox-serde-0.1+default-dev (>= 0.1.1-~~) <!nocheck>,
+ librust-proxmox-serde-0.1+serde-json-dev (>= 0.1.1-~~) <!nocheck>,
+ librust-serde-1+default-dev <!nocheck>
+Maintainer: Proxmox Support Team <support@proxmox.com>
+Standards-Version: 4.6.1
+Vcs-Git: git://git.proxmox.com/git/proxmox.git
+Vcs-Browser: https://git.proxmox.com/?p=proxmox.git
+X-Cargo-Crate: proxmox-human-byte
+Rules-Requires-Root: no
+
+Package: librust-proxmox-human-byte-dev
+Architecture: any
+Multi-Arch: same
+Depends:
+ ${misc:Depends},
+ librust-anyhow-1+default-dev,
+ librust-proxmox-schema-1+api-macro-dev (>= 1.3.7-~~),
+ librust-proxmox-schema-1+default-dev (>= 1.3.7-~~),
+ librust-proxmox-serde-0.1+default-dev (>= 0.1.1-~~),
+ librust-proxmox-serde-0.1+serde-json-dev (>= 0.1.1-~~),
+ librust-serde-1+default-dev
+Provides:
+ librust-proxmox-human-byte+default-dev (= ${binary:Version}),
+ librust-proxmox-human-byte-0-dev (= ${binary:Version}),
+ librust-proxmox-human-byte-0+default-dev (= ${binary:Version}),
+ librust-proxmox-human-byte-0.1-dev (= ${binary:Version}),
+ librust-proxmox-human-byte-0.1+default-dev (= ${binary:Version}),
+ librust-proxmox-human-byte-0.1.0-dev (= ${binary:Version}),
+ librust-proxmox-human-byte-0.1.0+default-dev (= ${binary:Version})
+Description: Proxmox library for formatting byte sizes (IEC or SI) - Rust source code
+ This package contains the source for the Rust proxmox-human-byte crate,
+ packaged by debcargo for use with cargo and dh-cargo.
diff --git a/proxmox-human-byte/debian/copyright b/proxmox-human-byte/debian/copyright
new file mode 100644
index 0000000..4fce23a
--- /dev/null
+++ b/proxmox-human-byte/debian/copyright
@@ -0,0 +1,16 @@
+Copyright (C) 2023 Proxmox Server Solutions GmbH
+
+This software is written by Proxmox Server Solutions GmbH <support@proxmox.com>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
diff --git a/proxmox-human-byte/debian/debcargo.toml b/proxmox-human-byte/debian/debcargo.toml
new file mode 100644
index 0000000..b7864cd
--- /dev/null
+++ b/proxmox-human-byte/debian/debcargo.toml
@@ -0,0 +1,7 @@
+overlay = "."
+crate_src_path = ".."
+maintainer = "Proxmox Support Team <support@proxmox.com>"
+
+[source]
+vcs_git = "git://git.proxmox.com/git/proxmox.git"
+vcs_browser = "https://git.proxmox.com/?p=proxmox.git"
diff --git a/proxmox-human-byte/src/lib.rs b/proxmox-human-byte/src/lib.rs
new file mode 100644
index 0000000..7be16a5
--- /dev/null
+++ b/proxmox-human-byte/src/lib.rs
@@ -0,0 +1,358 @@
+use anyhow::{bail, Error};
+
+use proxmox_schema::{ApiStringFormat, ApiType, Schema, StringSchema, UpdaterType};
+
+/// Size units for byte sizes
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+pub enum SizeUnit {
+    Byte,
+    // SI (base 10)
+    KByte,
+    MByte,
+    GByte,
+    TByte,
+    PByte,
+    // IEC (base 2)
+    Kibi,
+    Mebi,
+    Gibi,
+    Tebi,
+    Pebi,
+}
+
+impl SizeUnit {
+    /// Returns the scaling factor
+    pub fn factor(&self) -> f64 {
+        match self {
+            SizeUnit::Byte => 1.0,
+            // SI (base 10)
+            SizeUnit::KByte => 1_000.0,
+            SizeUnit::MByte => 1_000_000.0,
+            SizeUnit::GByte => 1_000_000_000.0,
+            SizeUnit::TByte => 1_000_000_000_000.0,
+            SizeUnit::PByte => 1_000_000_000_000_000.0,
+            // IEC (base 2)
+            SizeUnit::Kibi => 1024.0,
+            SizeUnit::Mebi => 1024.0 * 1024.0,
+            SizeUnit::Gibi => 1024.0 * 1024.0 * 1024.0,
+            SizeUnit::Tebi => 1024.0 * 1024.0 * 1024.0 * 1024.0,
+            SizeUnit::Pebi => 1024.0 * 1024.0 * 1024.0 * 1024.0 * 1024.0,
+        }
+    }
+
+    /// gets the biggest possible unit still having a value greater zero before the decimal point
+    /// 'binary' specifies if IEC (base 2) units should be used or SI (base 10) ones
+    pub fn auto_scale(size: f64, binary: bool) -> SizeUnit {
+        if binary {
+            let bits = 64 - (size as u64).leading_zeros();
+            match bits {
+                51.. => SizeUnit::Pebi,
+                41..=50 => SizeUnit::Tebi,
+                31..=40 => SizeUnit::Gibi,
+                21..=30 => SizeUnit::Mebi,
+                11..=20 => SizeUnit::Kibi,
+                _ => SizeUnit::Byte,
+            }
+        } else if size >= 1_000_000_000_000_000.0 {
+            SizeUnit::PByte
+        } else if size >= 1_000_000_000_000.0 {
+            SizeUnit::TByte
+        } else if size >= 1_000_000_000.0 {
+            SizeUnit::GByte
+        } else if size >= 1_000_000.0 {
+            SizeUnit::MByte
+        } else if size >= 1_000.0 {
+            SizeUnit::KByte
+        } else {
+            SizeUnit::Byte
+        }
+    }
+}
+
+/// Returns the string representation
+impl std::fmt::Display for SizeUnit {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            SizeUnit::Byte => write!(f, "B"),
+            // SI (base 10)
+            SizeUnit::KByte => write!(f, "KB"),
+            SizeUnit::MByte => write!(f, "MB"),
+            SizeUnit::GByte => write!(f, "GB"),
+            SizeUnit::TByte => write!(f, "TB"),
+            SizeUnit::PByte => write!(f, "PB"),
+            // IEC (base 2)
+            SizeUnit::Kibi => write!(f, "KiB"),
+            SizeUnit::Mebi => write!(f, "MiB"),
+            SizeUnit::Gibi => write!(f, "GiB"),
+            SizeUnit::Tebi => write!(f, "TiB"),
+            SizeUnit::Pebi => write!(f, "PiB"),
+        }
+    }
+}
+
+/// Strips a trailing SizeUnit inclusive trailing whitespace
+/// Supports both IEC and SI based scales, the B/b byte symbol is optional.
+fn strip_unit(v: &str) -> (&str, SizeUnit) {
+    let v = v.strip_suffix(&['b', 'B'][..]).unwrap_or(v); // byte is implied anyway
+
+    let (v, binary) = match v.strip_suffix('i') {
+        Some(n) => (n, true),
+        None => (v, false),
+    };
+
+    let mut unit = SizeUnit::Byte;
+    #[rustfmt::skip]
+        let value = v.strip_suffix(|c: char| match c {
+        'k' | 'K' if !binary => { unit = SizeUnit::KByte; true }
+        'm' | 'M' if !binary => { unit = SizeUnit::MByte; true }
+        'g' | 'G' if !binary => { unit = SizeUnit::GByte; true }
+        't' | 'T' if !binary => { unit = SizeUnit::TByte; true }
+        'p' | 'P' if !binary => { unit = SizeUnit::PByte; true }
+        // binary (IEC recommended) variants
+        'k' | 'K' if binary => { unit = SizeUnit::Kibi; true }
+        'm' | 'M' if binary => { unit = SizeUnit::Mebi; true }
+        'g' | 'G' if binary => { unit = SizeUnit::Gibi; true }
+        't' | 'T' if binary => { unit = SizeUnit::Tebi; true }
+        'p' | 'P' if binary => { unit = SizeUnit::Pebi; true }
+        _ => false
+    }).unwrap_or(v).trim_end();
+
+    (value, unit)
+}
+
+/// Byte size which can be displayed in a human friendly way
+#[derive(Debug, Copy, Clone, UpdaterType, PartialEq)]
+pub struct HumanByte {
+    /// The siginficant value, it does not includes any factor of the `unit`
+    size: f64,
+    /// The scale/unit of the value
+    unit: SizeUnit,
+}
+
+fn verify_human_byte(s: &str) -> Result<(), Error> {
+    match s.parse::<HumanByte>() {
+        Ok(_) => Ok(()),
+        Err(err) => bail!("byte-size parse error for '{}': {}", s, err),
+    }
+}
+impl ApiType for HumanByte {
+    const API_SCHEMA: Schema = StringSchema::new(
+        "Byte size with optional unit (B, KB (base 10), MB, GB, ..., KiB (base 2), MiB, Gib, ...).",
+    )
+    .format(&ApiStringFormat::VerifyFn(verify_human_byte))
+    .min_length(1)
+    .max_length(64)
+    .schema();
+}
+
+impl HumanByte {
+    /// Create instance with size and unit (size must be positive)
+    pub fn with_unit(size: f64, unit: SizeUnit) -> Result<Self, Error> {
+        if size < 0.0 {
+            bail!("byte size may not be negative");
+        }
+        Ok(HumanByte { size, unit })
+    }
+
+    /// Create a new instance with optimal binary unit computed
+    pub fn new_binary(size: f64) -> Self {
+        let unit = SizeUnit::auto_scale(size, true);
+        HumanByte {
+            size: size / unit.factor(),
+            unit,
+        }
+    }
+
+    /// Create a new instance with optimal decimal unit computed
+    pub fn new_decimal(size: f64) -> Self {
+        let unit = SizeUnit::auto_scale(size, false);
+        HumanByte {
+            size: size / unit.factor(),
+            unit,
+        }
+    }
+
+    /// Returns the size as u64 number of bytes
+    pub fn as_u64(&self) -> u64 {
+        self.as_f64() as u64
+    }
+
+    /// Returns the size as f64 number of bytes
+    pub fn as_f64(&self) -> f64 {
+        self.size * self.unit.factor()
+    }
+
+    /// Returns a copy with optimal binary unit computed
+    pub fn auto_scale_binary(self) -> Self {
+        HumanByte::new_binary(self.as_f64())
+    }
+
+    /// Returns a copy with optimal decimal unit computed
+    pub fn auto_scale_decimal(self) -> Self {
+        HumanByte::new_decimal(self.as_f64())
+    }
+}
+
+impl From<u64> for HumanByte {
+    fn from(v: u64) -> Self {
+        HumanByte::new_binary(v as f64)
+    }
+}
+impl From<usize> for HumanByte {
+    fn from(v: usize) -> Self {
+        HumanByte::new_binary(v as f64)
+    }
+}
+
+impl std::fmt::Display for HumanByte {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let precision = f.precision().unwrap_or(3) as f64;
+        let precision_factor = 1.0 * 10.0_f64.powf(precision);
+        // this could cause loss of information, rust has sadly no shortest-max-X flt2dec fmt yet
+        let size = ((self.size * precision_factor).round()) / precision_factor;
+        write!(f, "{} {}", size, self.unit)
+    }
+}
+
+impl std::str::FromStr for HumanByte {
+    type Err = Error;
+
+    fn from_str(v: &str) -> Result<Self, Error> {
+        let (v, unit) = strip_unit(v);
+        HumanByte::with_unit(v.parse()?, unit)
+    }
+}
+
+proxmox_serde::forward_deserialize_to_from_str!(HumanByte);
+proxmox_serde::forward_serialize_to_display!(HumanByte);
+
+#[test]
+fn test_human_byte_parser() -> Result<(), Error> {
+    assert!("-10".parse::<HumanByte>().is_err()); // negative size
+
+    fn do_test(v: &str, size: f64, unit: SizeUnit, as_str: &str) -> Result<(), Error> {
+        let h: HumanByte = v.parse()?;
+
+        if h.size != size {
+            bail!("got unexpected size for '{}' ({} != {})", v, h.size, size);
+        }
+        if h.unit != unit {
+            bail!(
+                "got unexpected unit for '{}' ({:?} != {:?})",
+                v,
+                h.unit,
+                unit
+            );
+        }
+
+        let new = h.to_string();
+        if new != *as_str {
+            bail!("to_string failed for '{}' ({:?} != {:?})", v, new, as_str);
+        }
+        Ok(())
+    }
+    fn test(v: &str, size: f64, unit: SizeUnit, as_str: &str) -> bool {
+        match do_test(v, size, unit, as_str) {
+            Ok(_) => true,
+            Err(err) => {
+                eprintln!("{}", err); // makes debugging easier
+                false
+            }
+        }
+    }
+
+    assert!(test("14", 14.0, SizeUnit::Byte, "14 B"));
+    assert!(test("14.4", 14.4, SizeUnit::Byte, "14.4 B"));
+    assert!(test("14.45", 14.45, SizeUnit::Byte, "14.45 B"));
+    assert!(test("14.456", 14.456, SizeUnit::Byte, "14.456 B"));
+    assert!(test("14.4567", 14.4567, SizeUnit::Byte, "14.457 B"));
+
+    let h: HumanByte = "1.2345678".parse()?;
+    assert_eq!(&format!("{:.0}", h), "1 B");
+    assert_eq!(&format!("{:.0}", h.as_f64()), "1"); // use as_f64 to get raw bytes without unit
+    assert_eq!(&format!("{:.1}", h), "1.2 B");
+    assert_eq!(&format!("{:.2}", h), "1.23 B");
+    assert_eq!(&format!("{:.3}", h), "1.235 B");
+    assert_eq!(&format!("{:.4}", h), "1.2346 B");
+    assert_eq!(&format!("{:.5}", h), "1.23457 B");
+    assert_eq!(&format!("{:.6}", h), "1.234568 B");
+    assert_eq!(&format!("{:.7}", h), "1.2345678 B");
+    assert_eq!(&format!("{:.8}", h), "1.2345678 B");
+
+    assert!(test(
+        "987654321",
+        987654321.0,
+        SizeUnit::Byte,
+        "987654321 B"
+    ));
+
+    assert!(test("1300b", 1300.0, SizeUnit::Byte, "1300 B"));
+    assert!(test("1300B", 1300.0, SizeUnit::Byte, "1300 B"));
+    assert!(test("1300 B", 1300.0, SizeUnit::Byte, "1300 B"));
+    assert!(test("1300 b", 1300.0, SizeUnit::Byte, "1300 B"));
+
+    assert!(test("1.5KB", 1.5, SizeUnit::KByte, "1.5 KB"));
+    assert!(test("1.5kb", 1.5, SizeUnit::KByte, "1.5 KB"));
+    assert!(test("1.654321MB", 1.654_321, SizeUnit::MByte, "1.654 MB"));
+
+    assert!(test("2.0GB", 2.0, SizeUnit::GByte, "2 GB"));
+
+    assert!(test("1.4TB", 1.4, SizeUnit::TByte, "1.4 TB"));
+    assert!(test("1.4tb", 1.4, SizeUnit::TByte, "1.4 TB"));
+
+    assert!(test("2KiB", 2.0, SizeUnit::Kibi, "2 KiB"));
+    assert!(test("2Ki", 2.0, SizeUnit::Kibi, "2 KiB"));
+    assert!(test("2kib", 2.0, SizeUnit::Kibi, "2 KiB"));
+
+    assert!(test("2.3454MiB", 2.3454, SizeUnit::Mebi, "2.345 MiB"));
+    assert!(test("2.3456MiB", 2.3456, SizeUnit::Mebi, "2.346 MiB"));
+
+    assert!(test("4gib", 4.0, SizeUnit::Gibi, "4 GiB"));
+
+    Ok(())
+}
+
+#[test]
+fn test_human_byte_auto_unit_decimal() {
+    fn convert(b: u64) -> String {
+        HumanByte::new_decimal(b as f64).to_string()
+    }
+    assert_eq!(convert(987), "987 B");
+    assert_eq!(convert(1022), "1.022 KB");
+    assert_eq!(convert(9_000), "9 KB");
+    assert_eq!(convert(1_000), "1 KB");
+    assert_eq!(convert(1_000_000), "1 MB");
+    assert_eq!(convert(1_000_000_000), "1 GB");
+    assert_eq!(convert(1_000_000_000_000), "1 TB");
+    assert_eq!(convert(1_000_000_000_000_000), "1 PB");
+
+    assert_eq!(convert((1 << 30) + 103 * (1 << 20)), "1.182 GB");
+    assert_eq!(convert((1 << 30) + 128 * (1 << 20)), "1.208 GB");
+    assert_eq!(convert((2 << 50) + 500 * (1 << 40)), "2.802 PB");
+}
+
+#[test]
+fn test_human_byte_auto_unit_binary() {
+    fn convert(b: u64) -> String {
+        HumanByte::from(b).to_string()
+    }
+    assert_eq!(convert(0), "0 B");
+    assert_eq!(convert(987), "987 B");
+    assert_eq!(convert(1022), "1022 B");
+    assert_eq!(convert(9_000), "8.789 KiB");
+    assert_eq!(convert(10_000_000), "9.537 MiB");
+    assert_eq!(convert(10_000_000_000), "9.313 GiB");
+    assert_eq!(convert(10_000_000_000_000), "9.095 TiB");
+
+    assert_eq!(convert(1 << 10), "1 KiB");
+    assert_eq!(convert((1 << 10) * 10), "10 KiB");
+    assert_eq!(convert(1 << 20), "1 MiB");
+    assert_eq!(convert(1 << 30), "1 GiB");
+    assert_eq!(convert(1 << 40), "1 TiB");
+    assert_eq!(convert(1 << 50), "1 PiB");
+
+    assert_eq!(convert((1 << 30) + 103 * (1 << 20)), "1.101 GiB");
+    assert_eq!(convert((1 << 30) + 128 * (1 << 20)), "1.125 GiB");
+    assert_eq!(convert((1 << 40) + 128 * (1 << 30)), "1.125 TiB");
+    assert_eq!(convert((2 << 50) + 512 * (1 << 40)), "2.5 PiB");
+}
-- 
2.30.2