use std::{
borrow::Cow,
ffi::OsStr,
fmt::Write,
path::{Path, PathBuf},
sync::Arc,
time::Duration,
};
use anyhow::{Context, Result};
use bytes::{Bytes, BytesMut};
use comrak::{ComrakOptions, ComrakPlugins};
use git2::{
BranchType, DiffFormat, DiffLineType, DiffOptions, DiffStatsFormat, ObjectType, Oid, Signature,
};
use moka::future::Cache;
use parking_lot::Mutex;
use syntect::{
html::{ClassStyle, ClassedHTMLGenerator},
parsing::SyntaxSet,
util::LinesWithEndings,
};
use time::OffsetDateTime;
use tracing::instrument;
use crate::syntax_highlight::ComrakSyntectAdapter;
pub struct Git {
commits: Cache<Oid, Arc<Commit>>,
readme_cache: Cache<PathBuf, Option<(ReadmeFormat, Arc<str>)>>,
syntax_set: SyntaxSet,
}
impl Git {
#[instrument(skip(syntax_set))]
pub fn new(syntax_set: SyntaxSet) -> Self {
Self {
commits: Cache::builder()
.time_to_live(Duration::from_secs(10))
.max_capacity(100)
.build(),
readme_cache: Cache::builder()
.time_to_live(Duration::from_secs(10))
.max_capacity(100)
.build(),
syntax_set,
}
}
}
impl Git {
#[instrument(skip(self))]
pub async fn repo(self: Arc<Self>, repo_path: PathBuf) -> Result<Arc<OpenRepository>> {
let repo = tokio::task::spawn_blocking({
let repo_path = repo_path.clone();
move || git2::Repository::open(repo_path)
})
.await
.context("Failed to join Tokio task")?
.context("Failed to open repository")?;
Ok(Arc::new(OpenRepository {
git: self,
cache_key: repo_path,
repo: Mutex::new(repo),
}))
}
}
pub struct OpenRepository {
git: Arc<Git>,
cache_key: PathBuf,
repo: Mutex<git2::Repository>,
}
impl OpenRepository {
pub async fn path(
self: Arc<Self>,
path: Option<PathBuf>,
tree_id: Option<&str>,
branch: Option<String>,
) -> Result<PathDestination> {
let tree_id = tree_id
.map(Oid::from_str)
.transpose()
.context("Failed to parse tree hash")?;
tokio::task::spawn_blocking(move || {
let repo = self.repo.lock();
let mut tree = if let Some(tree_id) = tree_id {
repo.find_tree(tree_id)
.context("Couldn't find tree with given id")?
} else if let Some(branch) = branch {
let branch = repo.find_branch(&branch, BranchType::Local)?;
branch
.get()
.peel_to_tree()
.context("Couldn't find tree for branch")?
} else {
let head = repo.head()?;
head.peel_to_tree()
.context("Couldn't find tree from HEAD")?
};
if let Some(path) = path.as_ref() {
let item = tree.get_path(path).context("Path doesn't exist in tree")?;
let object = item
.to_object(&repo)
.context("Path in tree isn't an object")?;
if let Some(blob) = object.as_blob() {
let name = String::from_utf8_lossy(item.name_bytes());
let path = path.clone().join(&*name);
let extension = path
.extension()
.or_else(|| path.file_name())
.map_or_else(|| Cow::Borrowed(""), OsStr::to_string_lossy);
let content = format_file(blob.content(), &extension, &self.git.syntax_set)?;
return Ok(PathDestination::File(FileWithContent {
metadata: File {
mode: item.filemode(),
size: blob.size(),
path,
name: name.into_owned(),
},
content,
}));
} else if let Ok(new_tree) = object.into_tree() {
tree = new_tree;
} else {
anyhow::bail!("Given path not tree nor blob... what is it?!");
}
}
let mut tree_items = Vec::new();
for item in tree.iter() {
let object = item
.to_object(&repo)
.context("Expected item in tree to be object but it wasn't")?;
let name = String::from_utf8_lossy(item.name_bytes()).into_owned();
let path = path.clone().unwrap_or_default().join(&name);
if let Some(blob) = object.as_blob() {
tree_items.push(TreeItem::File(File {
mode: item.filemode(),
size: blob.size(),
path,
name,
}));
} else if let Some(_tree) = object.as_tree() {
tree_items.push(TreeItem::Tree(Tree {
mode: item.filemode(),
path,
name,
}));
}
}
Ok(PathDestination::Tree(tree_items))
})
.await
.context("Failed to join Tokio task")?
}
#[instrument(skip(self))]
pub async fn tag_info(self: Arc<Self>, tag_name: &str) -> Result<DetailedTag> {
let reference = format!("refs/tags/{tag_name}");
let tag_name = tag_name.to_string();
tokio::task::spawn_blocking(move || {
let repo = self.repo.lock();
let tag = repo
.find_reference(&reference)
.context("Given reference does not exist in repository")?
.peel_to_tag()
.context("Couldn't get to a tag from the given reference")?;
let tag_target = tag.target().context("Couldn't find tagged object")?;
let tagged_object = match tag_target.kind() {
Some(ObjectType::Commit) => Some(TaggedObject::Commit(tag_target.id().to_string())),
Some(ObjectType::Tree) => Some(TaggedObject::Tree(tag_target.id().to_string())),
None | Some(_) => None,
};
Ok(DetailedTag {
name: tag_name,
tagger: tag.tagger().map(TryInto::try_into).transpose()?,
message: tag
.message_bytes()
.map_or_else(|| Cow::Borrowed(""), String::from_utf8_lossy)
.into_owned(),
tagged_object,
})
})
.await
.context("Failed to join Tokio task")?
}
#[instrument(skip(self))]
pub async fn readme(
self: Arc<Self>,
) -> Result<Option<(ReadmeFormat, Arc<str>)>, Arc<anyhow::Error>> {
const README_FILES: &[&str] = &["README.md", "README", "README.txt"];
let git = self.git.clone();
git.readme_cache
.try_get_with(self.cache_key.clone(), async move {
tokio::task::spawn_blocking(move || {
let repo = self.repo.lock();
let head = repo.head().context("Couldn't find HEAD of repository")?;
let commit = head.peel_to_commit().context(
"Couldn't find the commit that the HEAD of the repository refers to",
)?;
let tree = commit
.tree()
.context("Couldn't get the tree that the HEAD refers to")?;
for name in README_FILES {
let tree_entry = if let Some(file) = tree.get_name(name) {
file
} else {
continue;
};
let blob = if let Some(blob) = tree_entry
.to_object(&repo)
.ok()
.and_then(|v| v.into_blob().ok())
{
blob
} else {
continue;
};
let content = if let Ok(content) = std::str::from_utf8(blob.content()) {
content
} else {
continue;
};
if Path::new(name).extension().and_then(OsStr::to_str) == Some("md") {
let value = parse_and_transform_markdown(content, &self.git.syntax_set);
return Ok(Some((ReadmeFormat::Markdown, Arc::from(value))));
}
return Ok(Some((ReadmeFormat::Plaintext, Arc::from(content))));
}
Ok(None)
})
.await
.context("Failed to join Tokio task")?
})
.await
}
#[instrument(skip(self))]
pub async fn latest_commit(self: Arc<Self>) -> Result<Commit> {
tokio::task::spawn_blocking(move || {
let repo = self.repo.lock();
let head = repo.head().context("Couldn't find HEAD of repository")?;
let commit = head
.peel_to_commit()
.context("Couldn't find commit HEAD of repository refers to")?;
let (diff_plain, diff_output, diff_stats) =
fetch_diff_and_stats(&repo, &commit, &self.git.syntax_set)?;
let mut commit = Commit::try_from(commit)?;
commit.diff_stats = diff_stats;
commit.diff = diff_output;
commit.diff_plain = diff_plain;
Ok(commit)
})
.await
.context("Failed to join Tokio task")?
}
#[instrument(skip(self))]
pub async fn commit(self: Arc<Self>, commit: &str) -> Result<Arc<Commit>, Arc<anyhow::Error>> {
let commit = Oid::from_str(commit)
.map_err(anyhow::Error::from)
.map_err(Arc::new)?;
let git = self.git.clone();
git.commits
.try_get_with(commit, async move {
tokio::task::spawn_blocking(move || {
let repo = self.repo.lock();
let commit = repo.find_commit(commit)?;
let (diff_plain, diff_output, diff_stats) =
fetch_diff_and_stats(&repo, &commit, &self.git.syntax_set)?;
let mut commit = Commit::try_from(commit)?;
commit.diff_stats = diff_stats;
commit.diff = diff_output;
commit.diff_plain = diff_plain;
Ok(Arc::new(commit))
})
.await
.context("Failed to join Tokio task")?
})
.await
}
}
fn parse_and_transform_markdown(s: &str, syntax_set: &SyntaxSet) -> String {
let mut plugins = ComrakPlugins::default();
let highlighter = ComrakSyntectAdapter { syntax_set };
plugins.render.codefence_syntax_highlighter = Some(&highlighter);
comrak::markdown_to_html_with_plugins(s, &ComrakOptions::default(), &plugins)
}
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub enum ReadmeFormat {
Markdown,
Plaintext,
}
pub enum PathDestination {
Tree(Vec<TreeItem>),
File(FileWithContent),
}
pub enum TreeItem {
Tree(Tree),
File(File),
}
#[derive(Debug)]
pub struct Tree {
pub mode: i32,
pub name: String,
pub path: PathBuf,
}
#[derive(Debug)]
pub struct File {
pub mode: i32,
pub size: usize,
pub name: String,
pub path: PathBuf,
}
#[derive(Debug)]
pub struct FileWithContent {
pub metadata: File,
pub content: String,
}
#[derive(Debug)]
pub struct Branch {
pub name: String,
pub commit: Commit,
}
#[derive(Debug)]
pub struct Remote {
pub name: String,
}
#[derive(Debug)]
pub enum TaggedObject {
Commit(String),
Tree(String),
}
#[derive(Debug)]
pub struct DetailedTag {
pub name: String,
pub tagger: Option<CommitUser>,
pub message: String,
pub tagged_object: Option<TaggedObject>,
}
#[derive(Debug)]
pub struct CommitUser {
name: String,
email: String,
time: OffsetDateTime,
}
impl TryFrom<Signature<'_>> for CommitUser {
type Error = anyhow::Error;
fn try_from(v: Signature<'_>) -> Result<Self> {
Ok(CommitUser {
name: String::from_utf8_lossy(v.name_bytes()).into_owned(),
email: String::from_utf8_lossy(v.email_bytes()).into_owned(),
time: OffsetDateTime::from_unix_timestamp(v.when().seconds())?,
})
}
}
impl CommitUser {
pub fn name(&self) -> &str {
&self.name
}
pub fn email(&self) -> &str {
&self.email
}
pub fn time(&self) -> OffsetDateTime {
self.time
}
}
#[derive(Debug)]
pub struct Commit {
author: CommitUser,
committer: CommitUser,
oid: String,
tree: String,
parents: Vec<String>,
summary: String,
body: String,
pub diff_stats: String,
pub diff: String,
pub diff_plain: Bytes,
}
impl TryFrom<git2::Commit<'_>> for Commit {
type Error = anyhow::Error;
fn try_from(commit: git2::Commit<'_>) -> Result<Self> {
Ok(Commit {
author: CommitUser::try_from(commit.author())?,
committer: CommitUser::try_from(commit.committer())?,
oid: commit.id().to_string(),
tree: commit.tree_id().to_string(),
parents: commit.parent_ids().map(|v| v.to_string()).collect(),
summary: commit
.summary_bytes()
.map_or_else(|| Cow::Borrowed(""), String::from_utf8_lossy)
.into_owned(),
body: commit
.body_bytes()
.map_or_else(|| Cow::Borrowed(""), String::from_utf8_lossy)
.into_owned(),
diff_stats: String::with_capacity(0),
diff: String::with_capacity(0),
diff_plain: Bytes::new(),
})
}
}
impl Commit {
pub fn author(&self) -> &CommitUser {
&self.author
}
pub fn committer(&self) -> &CommitUser {
&self.committer
}
pub fn oid(&self) -> &str {
&self.oid
}
pub fn tree(&self) -> &str {
&self.tree
}
pub fn parents(&self) -> impl Iterator<Item = &str> {
self.parents.iter().map(String::as_str)
}
pub fn summary(&self) -> &str {
&self.summary
}
pub fn body(&self) -> &str {
&self.body
}
}
#[instrument(skip(repo, commit, syntax_set))]
fn fetch_diff_and_stats(
repo: &git2::Repository,
commit: &git2::Commit<'_>,
syntax_set: &SyntaxSet,
) -> Result<(Bytes, String, String)> {
let current_tree = commit.tree().context("Couldn't get tree for the commit")?;
let parent_tree = commit.parents().next().and_then(|v| v.tree().ok());
let mut diff_opts = DiffOptions::new();
let mut diff = repo.diff_tree_to_tree(
parent_tree.as_ref(),
Some(¤t_tree),
Some(&mut diff_opts),
)?;
let mut diff_plain = BytesMut::new();
let email = diff
.format_email(1, 1, commit, None)
.context("Couldn't build diff for commit")?;
diff_plain.extend_from_slice(&*email);
let diff_stats = diff
.stats()?
.to_buf(DiffStatsFormat::FULL, 80)?
.as_str()
.unwrap_or("")
.to_string();
let diff_output = format_diff(&diff, syntax_set)?;
Ok((diff_plain.freeze(), diff_output, diff_stats))
}
fn format_file(content: &[u8], extension: &str, syntax_set: &SyntaxSet) -> Result<String> {
let content = String::from_utf8_lossy(content);
let syntax = syntax_set
.find_syntax_by_extension(extension)
.unwrap_or_else(|| syntax_set.find_syntax_plain_text());
let mut html_generator =
ClassedHTMLGenerator::new_with_class_style(syntax, syntax_set, ClassStyle::Spaced);
for line in LinesWithEndings::from(&content) {
html_generator
.parse_html_for_line_which_includes_newline(line)
.context("Couldn't parse line of file")?;
}
Ok(format!(
"<code>{}</code>",
html_generator.finalize().replace('\n', "</code>\n<code>")
))
}
#[instrument(skip(diff, syntax_set))]
fn format_diff(diff: &git2::Diff<'_>, syntax_set: &SyntaxSet) -> Result<String> {
let mut diff_output = String::new();
diff.print(DiffFormat::Patch, |delta, _diff_hunk, diff_line| {
let (class, should_highlight_as_source) = match diff_line.origin_value() {
DiffLineType::Addition => (Some("add-line"), true),
DiffLineType::Deletion => (Some("remove-line"), true),
DiffLineType::Context => (Some("context"), true),
DiffLineType::AddEOFNL => (Some("remove-line"), false),
DiffLineType::DeleteEOFNL => (Some("add-line"), false),
DiffLineType::FileHeader => (Some("file-header"), false),
_ => (None, false),
};
let line = String::from_utf8_lossy(diff_line.content());
let extension = if should_highlight_as_source {
if let Some(path) = delta.new_file().path() {
path.extension()
.or_else(|| path.file_name())
.map_or_else(|| Cow::Borrowed(""), OsStr::to_string_lossy)
} else {
Cow::Borrowed("")
}
} else {
Cow::Borrowed("patch")
};
let syntax = syntax_set
.find_syntax_by_extension(&extension)
.unwrap_or_else(|| syntax_set.find_syntax_plain_text());
let mut html_generator =
ClassedHTMLGenerator::new_with_class_style(syntax, syntax_set, ClassStyle::Spaced);
let _res = html_generator.parse_html_for_line_which_includes_newline(&line);
if let Some(class) = class {
let _ = write!(diff_output, r#"<span class="diff-{class}">"#);
}
diff_output.push_str(&html_generator.finalize());
if class.is_some() {
diff_output.push_str("</span>");
}
true
})
.context("Failed to prepare diff")?;
Ok(diff_output)
}