diff --git a/libimagdiary/src/diaryid.rs b/libimagdiary/src/diaryid.rs
new file mode 100644
index 00000000..577a0b11
--- /dev/null
+++ b/libimagdiary/src/diaryid.rs
@@ -0,0 +1,188 @@
+use std::convert::Into;
+use std::str::FromStr;
+
+use chrono::naive::datetime::NaiveDateTime;
+use chrono::naive::time::NaiveTime;
+use chrono::naive::date::NaiveDate;
+use chrono::Datelike;
+use chrono::Timelike;
+use regex::Regex;
+
+use libimagstore::storeid::StoreId;
+use libimagstore::storeid::IntoStoreId;
+
+use module_path::ModuleEntryPath;
+
+#[derive(Debug, Clone)]
+pub struct DiaryId {
+    name: String,
+    year: i32,
+    month: u32,
+    day: u32,
+    hour: u32,
+    minute: u32,
+}
+
+impl DiaryId {
+
+    pub fn new(name: String, y: i32, m: u32, d: u32, h: u32, min: u32) -> DiaryId {
+        DiaryId {
+            name: name,
+            year: y,
+            month: m,
+            day: d,
+            hour: h,
+            minute: min,
+        }
+    }
+
+    pub fn from_datetime<DT: Datelike + Timelike>(diary_name: String, dt: DT) -> DiaryId {
+        DiaryId::new(diary_name, dt.year(), dt.month(), dt.day(), dt.hour(), dt.minute())
+    }
+
+    pub fn diary_name(&self) -> &String {
+        &self.name
+    }
+
+    pub fn year(&self) -> i32 {
+        self.year
+    }
+
+    pub fn month(&self) -> u32 {
+        self.month
+    }
+
+    pub fn day(&self) -> u32 {
+        self.day
+    }
+
+    pub fn hour(&self) -> u32 {
+        self.hour
+    }
+
+    pub fn minute(&self) -> u32 {
+        self.minute
+    }
+
+}
+
+impl IntoStoreId for DiaryId {
+
+    fn into_storeid(self) -> StoreId {
+        let s : String = self.into();
+        ModuleEntryPath::new(s).into_storeid()
+    }
+
+}
+
+impl Into<String> for DiaryId {
+
+    fn into(self) -> String {
+        format!("{}/{}/{}-{}-{}:{}",
+                self.name, self.year, self.month, self.day, self.hour, self.minute)
+    }
+
+}
+
+impl Into<NaiveDateTime> for DiaryId {
+
+    fn into(self) -> NaiveDateTime {
+        let d = NaiveDate::from_ymd(self.year, self.month, self.day);
+        let t = NaiveTime::from_hms(self.hour, self.minute, 0);
+        NaiveDateTime::new(d, t)
+    }
+
+}
+
+pub trait FromStoreId : Sized {
+
+    fn from_storeid(&StoreId) -> Option<Self>;
+
+}
+
+impl FromStoreId for DiaryId {
+
+    fn from_storeid(s: &StoreId) -> Option<DiaryId> {
+        lazy_static! {
+            static ref RE: Regex = Regex::new(r"(?x)
+            (.*)
+            /(?P<name>(.*))
+            /(?P<year>\d{4})
+            /(?P<month>\d{2})
+            -(?P<day>\d{2})
+            -(?P<hour>\d{2})
+            :(?P<minute>\d{2})
+            "
+            ).unwrap();
+        }
+
+        s.to_str()
+            .map(|s| { debug!("StoreId = {:?}", s); s })
+            .and_then(|s| RE.captures(s))
+            .and_then(|caps| {
+                let name   = caps.at(0);
+                let year   = caps.at(1);
+                let month  = caps.at(2);
+                let day    = caps.at(3);
+                let hour   = caps.at(4);
+                let minute = caps.at(5);
+
+                debug!("some? name   = {:?}", name.is_some());
+                debug!("some? year   = {:?}", year.is_some());
+                debug!("some? month  = {:?}", month.is_some());
+                debug!("some? day    = {:?}", day.is_some());
+                debug!("some? hour   = {:?}", hour.is_some());
+                debug!("some? minute = {:?}", minute.is_some());
+
+                if [name, year, month, day, hour, minute].iter().all(|x| x.is_some()) {
+                    let year = {
+                        match i32::from_str(year.unwrap()) {
+                            Ok(x) => x,
+                            Err(_) => return None,
+                        }
+                    };
+
+                    let month = {
+                        match u32::from_str(month.unwrap()) {
+                            Ok(x) => x,
+                            Err(_) => return None,
+                        }
+                    };
+
+                    let day = {
+                        match u32::from_str(day.unwrap()) {
+                            Ok(x) => x,
+                            Err(_) => return None,
+                        }
+                    };
+
+                    let hour = {
+                        match u32::from_str(hour.unwrap()) {
+                            Ok(x) => x,
+                            Err(_) => return None,
+                        }
+                    };
+
+                    let minute = {
+                        match u32::from_str(minute.unwrap()) {
+                            Ok(x) => x,
+                            Err(_) => return None,
+                        }
+                    };
+
+                    Some(DiaryId {
+                        name   : String::from(name.unwrap()),
+                        year   : year,
+                        month  : month,
+                        day    : day,
+                        hour   : hour,
+                        minute : minute,
+                    })
+                } else {
+                    None
+                }
+            })
+    }
+
+}
+