dodot_lib/handlers/
install.rs

1//! Install handler — runs setup scripts with checksum-based sentinel tracking.
2
3use std::io::Read;
4use std::path::Path;
5
6use sha2::{Digest, Sha256};
7
8use crate::datastore::DataStore;
9use crate::fs::Fs;
10use crate::handlers::{Handler, HandlerCategory, HandlerConfig, HandlerStatus, HANDLER_INSTALL};
11use crate::operations::HandlerIntent;
12use crate::paths::Pather;
13use crate::rules::RuleMatch;
14use crate::Result;
15
16pub struct InstallHandler<'a> {
17    fs: &'a dyn Fs,
18}
19
20impl<'a> InstallHandler<'a> {
21    pub fn new(fs: &'a dyn Fs) -> Self {
22        Self { fs }
23    }
24}
25
26impl Handler for InstallHandler<'_> {
27    fn name(&self) -> &str {
28        HANDLER_INSTALL
29    }
30
31    fn category(&self) -> HandlerCategory {
32        HandlerCategory::CodeExecution
33    }
34
35    fn to_intents(
36        &self,
37        matches: &[RuleMatch],
38        _config: &HandlerConfig,
39        _paths: &dyn Pather,
40    ) -> Result<Vec<HandlerIntent>> {
41        let mut intents = Vec::new();
42
43        for m in matches {
44            if m.is_dir {
45                continue;
46            }
47
48            let checksum = file_checksum(self.fs, &m.absolute_path)?;
49            let filename = m
50                .relative_path
51                .file_name()
52                .unwrap_or_default()
53                .to_string_lossy();
54            let sentinel = format!("{filename}-{checksum}");
55
56            intents.push(HandlerIntent::Run {
57                pack: m.pack.clone(),
58                handler: HANDLER_INSTALL.into(),
59                executable: "bash".into(),
60                arguments: vec!["--".into(), m.absolute_path.to_string_lossy().into_owned()],
61                sentinel,
62            });
63        }
64
65        Ok(intents)
66    }
67
68    fn check_status(
69        &self,
70        file: &Path,
71        pack: &str,
72        datastore: &dyn DataStore,
73    ) -> Result<HandlerStatus> {
74        let checksum = file_checksum(self.fs, file)?;
75        let filename = file.file_name().unwrap_or_default().to_string_lossy();
76        let sentinel = format!("{filename}-{checksum}");
77        let has_sentinel = datastore.has_sentinel(pack, HANDLER_INSTALL, &sentinel)?;
78
79        Ok(HandlerStatus {
80            file: file.to_string_lossy().into_owned(),
81            handler: HANDLER_INSTALL.into(),
82            deployed: has_sentinel,
83            message: if has_sentinel {
84                "installed".into()
85            } else {
86                "never run".into()
87            },
88        })
89    }
90}
91
92/// Compute a short SHA-256 hex digest of a file's contents.
93fn file_checksum(fs: &dyn Fs, path: &Path) -> Result<String> {
94    let mut reader = fs.open_read(path)?;
95    let mut hasher = Sha256::new();
96    let mut buf = [0u8; 8192];
97    loop {
98        let n = reader.read(&mut buf).map_err(|e| crate::DodotError::Fs {
99            path: path.to_path_buf(),
100            source: e,
101        })?;
102        if n == 0 {
103            break;
104        }
105        hasher.update(&buf[..n]);
106    }
107    let hash = hasher.finalize();
108    // Use first 8 bytes (16 hex chars) for a short but unique sentinel
109    Ok(hex::encode(&hash[..8]))
110}
111
112/// Minimal hex encoding (avoids pulling in the `hex` crate).
113mod hex {
114    pub fn encode(bytes: &[u8]) -> String {
115        bytes.iter().map(|b| format!("{b:02x}")).collect()
116    }
117}
118
119#[cfg(test)]
120mod tests {
121    use super::*;
122    use crate::testing::TempEnvironment;
123
124    #[test]
125    fn checksum_is_deterministic() {
126        let env = TempEnvironment::builder()
127            .pack("test")
128            .file("install.sh", "#!/bin/sh\necho hello")
129            .done()
130            .build();
131
132        let path = env.dotfiles_root.join("test/install.sh");
133        let c1 = file_checksum(env.fs.as_ref(), &path).unwrap();
134        let c2 = file_checksum(env.fs.as_ref(), &path).unwrap();
135        assert_eq!(c1, c2);
136        assert_eq!(c1.len(), 16); // 8 bytes = 16 hex chars
137    }
138
139    #[test]
140    fn checksum_changes_with_content() {
141        let env = TempEnvironment::builder()
142            .pack("test")
143            .file("a.sh", "version 1")
144            .file("b.sh", "version 2")
145            .done()
146            .build();
147
148        let ca = file_checksum(env.fs.as_ref(), &env.dotfiles_root.join("test/a.sh")).unwrap();
149        let cb = file_checksum(env.fs.as_ref(), &env.dotfiles_root.join("test/b.sh")).unwrap();
150        assert_ne!(ca, cb);
151    }
152
153    #[test]
154    fn to_intents_produces_run_with_sentinel() {
155        let env = TempEnvironment::builder()
156            .pack("vim")
157            .file("install.sh", "#!/bin/sh\nsetup")
158            .done()
159            .build();
160
161        let handler = InstallHandler::new(env.fs.as_ref());
162        let matches = vec![crate::rules::RuleMatch {
163            relative_path: "install.sh".into(),
164            absolute_path: env.dotfiles_root.join("vim/install.sh"),
165            pack: "vim".into(),
166            handler: "install".into(),
167            is_dir: false,
168            options: std::collections::HashMap::new(),
169        }];
170
171        let pather = crate::paths::XdgPather::builder()
172            .home(&env.home)
173            .dotfiles_root(&env.dotfiles_root)
174            .build()
175            .unwrap();
176
177        let intents = handler
178            .to_intents(&matches, &HandlerConfig::default(), &pather)
179            .unwrap();
180
181        assert_eq!(intents.len(), 1);
182        match &intents[0] {
183            HandlerIntent::Run {
184                executable,
185                arguments,
186                sentinel,
187                ..
188            } => {
189                assert_eq!(executable, "bash");
190                assert_eq!(arguments[0], "--");
191                assert!(arguments[1].contains("install.sh"));
192                assert!(sentinel.starts_with("install.sh-"));
193                assert_eq!(sentinel.len(), "install.sh-".len() + 16);
194            }
195            other => panic!("expected Run, got {other:?}"),
196        }
197    }
198}
dodot_lib/handlers/install.rs

dodot_lib/handlers/
install.rs
