pub type JournalState = StateContainer<JournalStateResolver, JournalEvent>;Expand description
Journal state tracks both log and live events from json files. It’s important to note however that state that is built from the json files is volatile and is only kept in memory. To save that part of the state you need to call JournalStateResolver::all_live_state and save the contents somewhere. Then, when you create your journal state again, use the From trait to create your instance, after which you can just feed state like normal again.
Below is a small example on how to manage this state.
use std::collections::HashMap;
use std::fs;
use std::path::Path;
use ed_journals::journal::auto_detect_journal_path;
use ed_journals::journal::blocking::LiveJournalDirReader;
use ed_journals::state::{JournalState, LiveStateEntryOwned};
// In this example we will save the live state to a file called 'live_state.json'.
let path = Path::new("live_state.json");
// Check if the file exists and create either create a default state or read the file and use
// that instead.
let mut state = if path.exists() {
// You need to create a HashMap with strings as keys and live states as values like shown
// below.
let string_contents = fs::read_to_string(&path).unwrap();
let parsed: HashMap<String, LiveStateEntryOwned> = serde_json::from_str(&string_contents).unwrap();
JournalState::from(parsed)
} else {
// If the path does not exist the default state is used.
JournalState::default()
};
// From here you can just use the state how you would normally. In this example a live reader is
// used to read and observe changes in the journal directory.
let journal_path = auto_detect_journal_path().unwrap();
let mut journal_reader = LiveJournalDirReader::open(&journal_path).unwrap();
for entry in journal_reader {
let entry = entry.unwrap();
state.feed(&entry);
if !entry.is_live {
continue;
}
state.flush();
// In this case we save the state to a file. In this example it's done every 'live' event.
// Then on subsequent launches of the application it will read the contents and use that.
let state_contents = serde_json::to_string(&state.all_live_state()).unwrap();
fs::write(&path, state_contents).unwrap();
}Aliased Type§
struct JournalState { /* private fields */ }