vtcode_commons/
file_input.rs

1//! File input helpers for provider-specific inline file attachments.
2
3use anyhow::{Context, Result};
4use base64::Engine as _;
5use std::path::Path;
6
7pub const MAX_INPUT_FILE_BYTES: u64 = 50 * 1024 * 1024;
8
9/// File data prepared for inline model input.
10#[derive(Debug, Clone, PartialEq, Eq)]
11pub struct FileInputData {
12    pub base64_data: String,
13    pub filename: String,
14    pub file_path: String,
15    pub size: u64,
16}
17
18/// Read a validated local file path for inline model input.
19///
20/// Callers must validate path scope and user intent before using this helper.
21pub async fn read_input_file_any_path<P: AsRef<Path>>(file_path: P) -> Result<FileInputData> {
22    let path = file_path.as_ref();
23    let metadata = tokio::fs::metadata(path)
24        .await
25        .with_context(|| format!("Failed to stat input file: {}", path.display()))?;
26
27    if !metadata.is_file() {
28        return Err(anyhow::anyhow!("Input path is not a file: {}", path.display()));
29    }
30
31    if metadata.len() > MAX_INPUT_FILE_BYTES {
32        return Err(anyhow::anyhow!(
33            "Input file too large: {} bytes (max {} bytes)",
34            metadata.len(),
35            MAX_INPUT_FILE_BYTES
36        ));
37    }
38
39    let file_contents = tokio::fs::read(path)
40        .await
41        .with_context(|| format!("Failed to read input file: {}", path.display()))?;
42
43    let filename = path
44        .file_name()
45        .and_then(|name| name.to_str())
46        .filter(|name| !name.is_empty())
47        .map(ToOwned::to_owned)
48        .unwrap_or_else(|| path.display().to_string());
49
50    Ok(FileInputData {
51        base64_data: base64::engine::general_purpose::STANDARD.encode(&file_contents),
52        filename,
53        file_path: path.display().to_string(),
54        size: file_contents.len() as u64,
55    })
56}
57
58pub fn decoded_base64_size(file_data: &str) -> Result<u64> {
59    let payload = inline_base64_payload(file_data);
60    let decoded = base64::engine::general_purpose::STANDARD
61        .decode(payload)
62        .context("Invalid base64 file_data payload")?;
63    Ok(decoded.len() as u64)
64}
65
66fn inline_base64_payload(file_data: &str) -> &str {
67    let trimmed = file_data.trim();
68    if let Some((prefix, payload)) = trimmed.split_once(',')
69        && prefix.contains(";base64")
70    {
71        payload.trim()
72    } else {
73        trimmed
74    }
75}
76
77#[cfg(test)]
78mod tests {
79    use super::{MAX_INPUT_FILE_BYTES, decoded_base64_size};
80
81    #[test]
82    fn decoded_base64_size_supports_raw_base64() {
83        assert_eq!(decoded_base64_size("aGVsbG8=").unwrap(), 5);
84    }
85
86    #[test]
87    fn decoded_base64_size_supports_data_url_prefix() {
88        assert_eq!(decoded_base64_size("data:application/pdf;base64,aGVsbG8=").unwrap(), 5);
89    }
90
91    #[test]
92    fn max_input_file_bytes_matches_openai_limit() {
93        assert_eq!(MAX_INPUT_FILE_BYTES, 50 * 1024 * 1024);
94    }
95}
vtcode_commons/file_input.rs

vtcode_commons/
file_input.rs
