Add first pass at using inotify to watch the job directory for changes

There are number of cases which currently aren't handled:

 * moving a file out of or into the directory
 * a file being touched: should that be used to reset that last_run
   value?
 * when jobs are removed, it is regardless of thread state so there
   may be children that never get joined

Cargo.lock

@@ -620,6 +620,7 @@ version = "0.1.0"
 dependencies = [
  "ansi-to-html",
  "chrono",
+ "inotify",
  "prettydiff",
  "rss",
  "scraper",
@@ -757,6 +758,28 @@ dependencies = [
  "hashbrown",
 ]
 
+[[package]]
+name = "inotify"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "abf888f9575c290197b2c948dc9e9ff10bd1a39ad1ea8585f734585fa6b9d3f9"
+dependencies = [
+ "bitflags",
+ "futures-core",
+ "inotify-sys",
+ "libc",
+ "tokio",
+]
+
+[[package]]
+name = "inotify-sys"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e05c02b5e89bff3b946cedeca278abc628fe811e604f027c45a8aa3cf793d0eb"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "instant"
 version = "0.1.12"

Cargo.toml

@@ -8,6 +8,7 @@ edition = "2021"
 [dependencies]
 ansi-to-html = "0.1"
 chrono = "0.4"
+inotify = "0.10"
 prettydiff = "0.6"
 rss = "2"
 scraper = "0.13"

src/conf.rs

@@ -22,36 +22,13 @@ impl Conf {
     }
 
     pub fn update_from_file(&mut self, path: &Path) {
-        let mut file = match std::fs::File::open(path) {
-            Err(why) => {
-                println!("Could not open file '{}': {}", path.display(), why); return;
-            },
-            Ok(file) => file,
+        let items = match read_conf_file(path) {
+            Err(_) => return,
+            Ok(items) => items,
         };
-        let mut content = String::new();
-        match file.read_to_string(&mut content) {
-            Err(why) => println!("Could not read from file '{}': {}", path.display(), why),
-            Ok(_) => (),
-        }
-
-        let lines = content.lines();
-        for line in lines {
-            if line.starts_with('#') {
-                continue;
-            }
-            let result = line.split_once('=');
-            if result.is_none() {
-                println!("Skipping configuration line '{}', no key-value delimiter (=) found", line);
-                continue;
-            }
-
-            let key = result.unwrap().0.trim();
-            let value = result.unwrap().1.trim();
-            if key.eq("") || value.eq("") {
-                println!("Skipping configuration line '{}', no key or value side is empty", line);
-                continue;
-            }
-
+        for item in items.iter() {
+            let key = item.0.as_str();
+            let value = item.1.as_str();
             match key {
                 "job_dir" => {
                     println!("{} changed from '{}' to '{}' by line in '{}'",
@@ -83,6 +60,46 @@ impl Conf {
     }
 }
 
+pub fn read_conf_file(path: &Path) -> Result<std::vec::Vec<(String, String)>, &str> {
+    let mut file = match std::fs::File::open(path) {
+        Err(why) => {
+            println!("Could not open file '{}': {}", path.display(), why);
+            return Err("Could not open file");
+        },
+        Ok(file) => file,
+    };
+    let mut content = String::new();
+    match file.read_to_string(&mut content) {
+        Err(why) => {
+            println!("Could not read from file '{}': {}", path.display(), why);
+            return Err("Could not read file");
+        },
+        Ok(_) => (),
+    }
+
+    let mut results = std::vec::Vec::<(String, String)>::new();
+    let lines = content.lines();
+    for line in lines {
+        if line.starts_with('#') {
+            continue;
+        }
+        let result = line.split_once('=');
+        if result.is_none() {
+            println!("Skipping configuration line '{}', no key-value delimiter (=) found", line);
+            continue;
+        }
+
+        let key = result.unwrap().0.trim();
+        let value = result.unwrap().1.trim();
+        if key.eq("") || value.eq("") {
+            println!("Skipping configuration line '{}', no key or value side is empty", line);
+            continue;
+        }
+        results.push((key.to_string(), value.to_string()));
+    }
+    return Ok(results);
+}
+
 #[cfg(test)]
 mod tests {
 

src/job.rs

@@ -0,0 +1,240 @@
+use std::path::{Path,PathBuf};
+use std::str::FromStr;
+use std::time::Duration;
+use std::time::Instant;
+
+use ansi_to_html;
+use chrono;
+use rss;
+
+use crate::conf::Conf;
+
+pub struct Job {
+    pub url: String,
+    pub selector: String,
+    pub every: Duration,
+    pub last_run: Option<Instant>,
+    pub output_file: Option<PathBuf>,
+    pub channel: Option<rss::Channel>,
+    pub source_file: Option<PathBuf>,
+}
+
+impl Job {
+
+    fn default(conf: &Conf) -> Job {
+        return Job {
+            url: "".to_string(),
+            selector: "".to_string(),
+            every: conf.check_interval,
+            last_run: None,
+            output_file: None,
+            channel: None,
+            source_file: None,
+        };
+    }
+
+    fn set_default_output_file(&mut self, conf: &Conf) {
+        let mut output_file = conf.output_dir.clone();
+        let mut file_name = self.url.clone().replace("/", "-");
+        file_name.push_str(".rss");
+        output_file = output_file.join(Path::new(&file_name));
+        self.output_file = Some(output_file);
+    }
+
+    fn set_default_channel(&mut self) {
+        match std::fs::File::open(self.output_file.as_ref().unwrap()) {
+            Err(why) => {
+                println!("Failed to open '{}': {}", self.output_file.as_ref().unwrap().display(), why);
+                println!("Creating empty RSS channel for job '{}'", self.url);
+                self.channel = Some(
+                    rss::ChannelBuilder::default()
+                        .title(self.url.as_str())
+                        .link(self.url.as_str())
+                        .description("haunting")
+                        .build()
+                );
+                self.channel.as_mut().unwrap().set_generator("Haunter".to_string());
+            },
+            Ok(file) => {
+                self.channel = Some(
+                    rss::Channel::read_from(std::io::BufReader::new(file)).unwrap()
+                );
+            },
+        };
+    }
+
+    pub fn has_job_file_extension(path: &Path) -> bool {
+        match path.extension() {
+            Some(x) => {
+                if ! "job".eq(x) {
+                    return false;
+                }
+            },
+            None => {
+                return false;
+            }
+        };
+        return true;
+    }
+
+    pub fn new(url: &str, selector: &str, conf: &Conf) -> Job {
+        let mut job = Job::default(conf);
+        job.url = url.to_string();
+        job.set_default_output_file(conf);
+        job.selector = selector.to_string();
+        job.set_default_channel();
+        return job;
+    }
+
+    pub fn from_file<'a>(path: &'a Path, conf: &'a Conf) -> Result<Job, &'a str> {
+        let mut job = Job::default(conf);
+        let items = match crate::conf::read_conf_file(path) {
+            Err(_) => return Err("Failed to read from configuration file"),
+            Ok(items) => items,
+        };
+        for item in items.iter() {
+            let key = item.0.as_str();
+            match key {
+                "url" => {
+                    job.url = item.1.clone();
+                },
+                "selector" => {
+                    job.selector = item.1.clone();
+                },
+                "every" => {
+                    let converted_value = match item.1.parse::<u64>() {
+                        Err(why) => {
+                            println!("Failed to convert '{}' to u64: {}", item.1, why);
+                            return Err("Failed to parse value of 'every'");
+                        },
+                        Ok(v) => v,
+                    };
+                    job.every = Duration::new(converted_value, 0);
+                },
+                "output_file" => {
+                    job.output_file = Some(
+                        conf.output_dir.join(PathBuf::from_str(item.1.as_str()).unwrap())
+                    );
+                }
+                _ => {
+                    println!("Unknown key '{}' in job file '{}'", key, path.display());
+                    return Err("Unknown key");
+                }
+            }
+        }
+        if job.output_file.is_none() {
+            job.set_default_output_file(conf);
+        }
+        job.set_default_channel();
+        job.source_file = Some(PathBuf::from(path));
+        return Ok(job);
+    }
+
+    pub fn update(&mut self, value: &str, diff: &str) {
+        if self.channel.is_none() {
+            println!("Skipping update of channel: no channel set");
+            return;
+        }
+        let channel = self.channel.as_mut().unwrap();
+        let update_time = chrono::Utc::now();
+        let item = rss::ItemBuilder::default()
+            .title(format!("Update to '{}'", self.url))
+            .link(self.url.clone())
+            .pub_date(update_time.to_rfc2822())
+            .content(format!(r#"
+New content at {}: <br>
+<pre class="new-value">
+{}
+</pre>
+<br><br>
+Diff: <br>
+<pre class="diff-value">
+{}
+</pre>
+"#,
+                             update_time.format("%d/%m/%Y %H:%M"),
+                             ansi_to_html::convert_escaped(value).unwrap().as_str(),
+                             ansi_to_html::convert_escaped(diff).unwrap().as_str()
+                )
+            )
+            .build();
+
+        channel.items.push(item);
+
+        if self.output_file.is_some() {
+            match std::fs::File::create(self.output_file.as_ref().unwrap()) {
+                Err(why) => {
+                    println!("Failed to open '{}' for writing: {}", self.output_file.as_ref().unwrap().display(), why);
+                },
+                Ok(file) => {
+                    channel.write_to(
+                        std::io::BufWriter::new(file)
+                    ).expect("Failed to write updated channel");
+                },
+            };
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use std::io::Write;
+    use tempfile::NamedTempFile;
+
+    #[test]
+    fn create() {
+        let conf = Conf::get_default_conf();
+        let job = Job::new(&"my/url", &"myselector", &conf);
+        assert_eq!(job.url, "my/url");
+        assert_eq!(job.output_file.unwrap().to_str().unwrap(), "results.d/my-url.rss");
+        assert_eq!(job.selector, "myselector");
+        assert!(job.source_file.is_none());
+        assert!(job.channel.is_some());
+    }
+
+    #[test]
+    fn create_from_file() {
+        let conf = Conf::get_default_conf();
+        let mut tf = NamedTempFile::new().unwrap();
+        let job_conf = r#"
+url = http://example.com/test
+output_file = example_output.atom
+every=7200
+
+selector = section.listing:nth-child(2) > ul:nth-child(1) > li:nth-child(3) > header:nth-child(3) > h2:nth-child(1) > a:nth-child(1)
+"#;
+        tf.write_all(job_conf.as_bytes()).expect("Failed to write configuration to file");
+
+        let job = Job::from_file(tf.path(), &conf).expect("Failed to read configuration file");
+        assert_eq!(job.url, "http://example.com/test");
+        assert_eq!(job.output_file.unwrap().to_str().unwrap(), "results.d/example_output.atom");
+        assert_eq!(job.every.as_secs(), 7200);
+        assert_eq!(job.selector, "section.listing:nth-child(2) > ul:nth-child(1) > li:nth-child(3) > header:nth-child(3) > h2:nth-child(1) > a:nth-child(1)");
+        assert_eq!(job.source_file.unwrap().to_str(), tf.path().to_str());
+        assert!(job.channel.is_some());
+    }
+
+    #[test]
+    fn create_from_file_default_output_file() {
+        let conf = Conf::get_default_conf();
+        let mut tf = NamedTempFile::new().unwrap();
+        let job_conf = r#"
+url = http://example.com/test
+every=7200
+
+selector = section.listing:nth-child(2) > ul:nth-child(1) > li:nth-child(3) > header:nth-child(3) > h2:nth-child(1) > a:nth-child(1)
+"#;
+        tf.write_all(job_conf.as_bytes()).expect("Failed to write configuration to file");
+
+        let job = Job::from_file(tf.path(), &conf).expect("Failed to read configuration file");
+        assert_eq!(job.url, "http://example.com/test");
+        assert_eq!(job.output_file.unwrap().to_str().unwrap(), "results.d/http:--example.com-test.rss");
+        assert_eq!(job.every.as_secs(), 7200);
+        assert_eq!(job.selector, "section.listing:nth-child(2) > ul:nth-child(1) > li:nth-child(3) > header:nth-child(3) > h2:nth-child(1) > a:nth-child(1)");
+        assert_eq!(job.source_file.unwrap().to_str(), tf.path().to_str());
+        assert!(job.channel.is_some());
+    }
+
+}

src/main.rs

@@ -1,111 +1,18 @@
 use std::cmp::Ordering;
 use std::env;
 use std::path::{Path,PathBuf};
-use std::str::FromStr;
 use std::thread;
 use std::time::Duration;
 use std::time::Instant;
 
-use ansi_to_html;
-use chrono;
-use rss;
+use inotify;
 use thirtyfour_sync::WebDriverCommands;
 
 mod conf;
 use conf::Conf;
 
-struct Job {
-    url: String,
-    selector: String,
-    every: Duration,
-    last_run: Option<Instant>,
-    output_file: Option<PathBuf>,
-    channel: Option<rss::Channel>,
-}
-
-impl Job {
-    fn new(url: &str, selector: &str, conf: &Conf) -> Job {
-        let mut job = Job {
-            url: String::from_str(url).unwrap(),
-            selector: String::from_str(selector).unwrap(),
-            every: conf.check_interval,
-            last_run: None,
-            output_file: None,
-            channel: None,
-        };
-        let mut output_file = conf.output_dir.clone();
-        let mut file_name = job.url.clone().replace("/", "-");
-        file_name.push_str(".rss");
-        output_file = output_file.join(Path::new(&file_name));
-        job.output_file = Some(output_file);
-
-        match std::fs::File::open(job.output_file.as_ref().unwrap()) {
-            Err(why) => {
-                println!("Failed to open '{}': {}", job.output_file.as_ref().unwrap().display(), why);
-                println!("Creating empty RSS channel for job '{}'", job.url);
-                job.channel = Some(
-                    rss::ChannelBuilder::default()
-                        .title(url)
-                        .link(url)
-                        .description("haunting")
-                        .build()
-                );
-                job.channel.as_mut().unwrap().set_generator("Haunter".to_string());
-            },
-            Ok(file) => {
-                job.channel = Some(
-                    rss::Channel::read_from(std::io::BufReader::new(file)).unwrap()
-                );
-            },
-        };
-        return job;
-    }
-
-    fn update(&mut self, value: &str, diff: &str) {
-        if self.channel.is_none() {
-            println!("Skipping update of channel: no channel set");
-            return;
-        }
-        let channel = self.channel.as_mut().unwrap();
-        let update_time = chrono::Utc::now();
-        let item = rss::ItemBuilder::default()
-            .title(format!("Update to '{}'", self.url))
-            .link(self.url.clone())
-            .pub_date(update_time.to_rfc2822())
-            .content(format!(r#"
-New content at {}: <br>
-<pre class="new-value">
-{}
-</pre>
-<br><br>
-Diff: <br>
-<pre class="diff-value">
-{}
-</pre>
-"#,
-                             update_time.format("%d/%m/%Y %H:%M"),
-                             ansi_to_html::convert_escaped(value).unwrap().as_str(),
-                             ansi_to_html::convert_escaped(diff).unwrap().as_str()
-                )
-            )
-            .build();
-
-        channel.items.push(item);
-
-        if self.output_file.is_some() {
-            match std::fs::File::create(self.output_file.as_ref().unwrap()) {
-                Err(why) => {
-                    println!("Failed to open '{}' for writing: {}", self.output_file.as_ref().unwrap().display(), why);
-                },
-                Ok(file) => {
-                    channel.write_to(
-                        std::io::BufWriter::new(file)
-                    ).expect("Failed to write updated channel");
-                },
-            };
-        }
-    }
-}
+mod job;
+use job::Job;
 
 struct ThreadJob {
     job: Job,
@@ -176,23 +83,50 @@ fn main() {
         std::process::exit(1);
     }
 
-    let mut jobs = Vec::new();
-    let some_job = Job::new("https://www.rust-lang.org", "a.download-link", &conf);
-    let other_job = Job::new(
-        "https://arstechnica.com/",
-        "section.listing:nth-child(2) > ul:nth-child(1) > li:nth-child(3) > header:nth-child(3) > h2:nth-child(1) > a:nth-child(1)",
-        &conf
-    );
+    let mut jobs: Vec<ThreadJob> = Vec::new();
+
+    // Load all jobs from job directory
+    let job_dir = conf.job_dir.clone();
+    for entry in std::fs::read_dir(job_dir).expect("Failed to iterate over job directory") {
+        let _entry = match entry {
+            Err(why) => {
+                println!("Skipping '{}': Error reading file in job directory", why);
+                continue;
+            },
+            Ok(value) => value,
+        };
+        let md = _entry.metadata().expect("Failed to read file metadata");
+        if !md.is_file() {
+            println!("Skipping '{}': not a file", _entry.path().display());
+            continue;
+        }
+
+        if !Job::has_job_file_extension(&_entry.path()) {
+            println!("Skipping '{}': does not have '.job' extension", _entry.path().display());
+            continue;
+        }
+
+        let job = match Job::from_file(&_entry.path(), &conf) {
+            Err(why) => {
+                println!("Failed to load job from '{}': {}", _entry.path().display(), why);
+                continue;
+            },
+            Ok(value) => value,
+        };
         jobs.push(ThreadJob {
-        job: some_job,
-        handle: None,
-        last_result: None,
-    });
-    jobs.push(ThreadJob {
-        job: other_job,
+            job: job,
             handle: None,
             last_result: None,
         });
+    }
+
+    let mut inotify = inotify::Inotify::init()
+        .expect("Failed to initialize inotify");
+    inotify.add_watch(
+        conf.job_dir.to_str().unwrap().clone(),
+        inotify::WatchMask::CREATE | inotify::WatchMask::DELETE
+    ).expect("Failed to start watching job dir for changes");
+    let mut notify_buffer = [0; 1024];
 
     let max_running_tasks = 5;
     loop {
@@ -258,13 +192,69 @@ fn main() {
                         break;
                     }
                 }
-                else {
-                    let time_since_last_run = Instant::now().duration_since(tj.job.last_run.unwrap());
-                    println!("Job '{}' - {}s since last run", tj.job.url, time_since_last_run.as_secs());
-                }
             }
             break;
         }
+
+        let events = inotify.read_events(&mut notify_buffer);
+        if events.is_ok() {
+            for event in events.unwrap() {
+                if event.name.is_none() {
+                    continue;
+                }
+                let mut path = PathBuf::new();
+                path.push(&conf.job_dir.to_str().unwrap().clone());
+                path.push(event.name.unwrap());
+                match event.mask {
+                    inotify::EventMask::CREATE => {
+                        let md = match path.metadata() {
+                            Err(why) => {
+                                println!("Failed to read metadata from event file '{}': {}",
+                                         path.display(), why);
+                                continue;
+                            },
+                            Ok(value) => value,
+                        };
+                        if !md.is_file() {
+                            continue;
+                        }
+                        if !Job::has_job_file_extension(&path) {
+                            continue;
+                        }
+
+                        let job = match Job::from_file(&path, &conf) {
+                            Err(why) => {
+                                println!("Failed to load job from '{}': {}", path.display(), why);
+                                continue;
+                            },
+                            Ok(value) => value,
+                        };
+                        jobs.push(ThreadJob {
+                            job: job,
+                            handle: None,
+                            last_result: None,
+                        });
+                        println!("Added job from '{}' being created", path.display());
+                    },
+                    inotify::EventMask::DELETE => {
+                        let x = jobs.len();
+                        // @TODO If a thread is currently running, we never join it again.
+                        jobs.retain(
+                            |tj|
+                            !(tj.job.source_file.is_some() && path.to_str().eq(&tj.job.source_file.as_ref().unwrap().to_str()))
+                        );
+                        println!(
+                            "{} jobs removed due to deletion of '{}'",
+                            x - jobs.len(), path.display()
+                        );
+                    },
+                    mask => {
+                        println!("Unhandled event mask: {:?}", mask);
+                        continue;
+                    }
+                };
+            }
+        }
         std::thread::sleep(Duration::new(1, 0));
     }
 }