Implement 'ta import'

Tests include "TODO" notes for data not handled by TaskChampion,
including links to the associated GitHub issues.

cli/src/invocation/cmd/import.rs

@@ -0,0 +1,257 @@
+use anyhow::{anyhow, bail};
+use chrono::{DateTime, TimeZone, Utc};
+use serde::{self, Deserialize, Deserializer};
+use serde_json::Value;
+use std::collections::HashMap;
+use taskchampion::{Replica, Uuid};
+use termcolor::WriteColor;
+
+pub(crate) fn execute<W: WriteColor>(w: &mut W, replica: &mut Replica) -> Result<(), crate::Error> {
+    writeln!(w, "Importing tasks from stdin.")?;
+    let tasks: Vec<HashMap<String, Value>> =
+        serde_json::from_reader(std::io::stdin()).map_err(|_| anyhow!("Invalid JSON"))?;
+
+    for task_json in &tasks {
+        import_task(w, replica, task_json)?;
+    }
+
+    writeln!(w, "{} tasks imported.", tasks.len())?;
+    Ok(())
+}
+
+/// Convert the given value to a string, failing on compound types (arrays
+/// and objects).
+fn stringify(v: &Value) -> anyhow::Result<String> {
+    Ok(match v {
+        Value::String(ref s) => s.clone(),
+        Value::Number(n) => n.to_string(),
+        Value::Bool(true) => "true".to_string(),
+        Value::Bool(false) => "false".to_string(),
+        Value::Null => "null".to_string(),
+        _ => bail!("{:?} cannot be converted to a string", v),
+    })
+}
+
+pub fn deserialize_tw_datetime<'de, D>(deserializer: D) -> Result<DateTime<Utc>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    const FORMAT: &str = "%Y%m%dT%H%M%SZ";
+    let s = String::deserialize(deserializer)?;
+    Utc.datetime_from_str(&s, FORMAT)
+        .map_err(serde::de::Error::custom)
+}
+
+/// Deserialize a string in the TaskWarrior format into a DateTime
+#[derive(Deserialize)]
+struct TwDateTime(#[serde(deserialize_with = "deserialize_tw_datetime")] DateTime<Utc>);
+
+impl TwDateTime {
+    /// Generate the data-model style UNIX timestamp for this DateTime
+    fn tc_timestamp(&self) -> String {
+        self.0.timestamp().to_string()
+    }
+}
+
+#[derive(Deserialize)]
+struct Annotation {
+    entry: TwDateTime,
+    description: String,
+}
+
+fn import_task<W: WriteColor>(
+    w: &mut W,
+    replica: &mut Replica,
+    // TOOD: take this by value and consume it
+    task_json: &HashMap<String, Value>,
+) -> anyhow::Result<()> {
+    let uuid = task_json
+        .get("uuid")
+        .ok_or_else(|| anyhow!("task has no uuid"))?;
+    let uuid = uuid
+        .as_str()
+        .ok_or_else(|| anyhow!("uuid is not a string"))?;
+    let uuid = Uuid::parse_str(uuid)?;
+    replica.create_task(uuid)?;
+
+    let mut description = None;
+    for (k, v) in task_json.iter() {
+        match k.as_ref() {
+            // `id` is the working-set ID and is not stored
+            "id" => {}
+
+            // `urgency` is also calculated and not stored
+            "urgency" => {}
+
+            // `uuid` was already handled
+            "uuid" => {}
+
+            // `annotations` is a sub-aray
+            "annotations" => {
+                let annotations: Vec<Annotation> = serde_json::from_value(v.clone())?;
+                for ann in annotations {
+                    let k = format!("annotation_{}", ann.entry.tc_timestamp());
+                    replica.update_task(uuid, k, Some(ann.description))?;
+                }
+            }
+
+            // `depends` is a sub-aray
+            "depends" => {
+                let deps: Vec<String> = serde_json::from_value(v.clone())?;
+                for dep in deps {
+                    let k = format!("dep_{}", dep);
+                    replica.update_task(uuid, k, Some("".to_owned()))?;
+                }
+            }
+
+            // `tags` is a sub-aray
+            "tags" => {
+                let tags: Vec<String> = serde_json::from_value(v.clone())?;
+                for tag in tags {
+                    let k = format!("tag_{}", tag);
+                    replica.update_task(uuid, k, Some("".to_owned()))?;
+                }
+            }
+
+            // convert all datetimes -> epoch integers
+            "end" | "entry" | "modified" | "wait" | "due" => {
+                let v: TwDateTime = serde_json::from_value(v.clone())?;
+                replica.update_task(uuid, k, Some(v.tc_timestamp()))?;
+            }
+
+            // everything else is inserted directly
+            _ => {
+                let v = stringify(v)?;
+                replica.update_task(uuid, k, Some(v.clone()))?;
+                if k == "description" {
+                    description = Some(v);
+                }
+            }
+        }
+    }
+
+    writeln!(
+        w,
+        "{} {}",
+        uuid,
+        description.unwrap_or_else(|| "(no description)".into())
+    )?;
+
+    Ok(())
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use crate::invocation::test::*;
+    use chrono::{TimeZone, Utc};
+    use pretty_assertions::assert_eq;
+    use serde_json::json;
+    use std::convert::TryInto;
+    use taskchampion::{Priority, Status};
+
+    #[test]
+    fn stringify_string() {
+        assert_eq!(stringify(&json!("foo")).unwrap(), "foo".to_string());
+    }
+
+    #[test]
+    fn stringify_number() {
+        assert_eq!(stringify(&json!(2.14)).unwrap(), "2.14".to_string());
+    }
+
+    #[test]
+    fn stringify_bool() {
+        assert_eq!(stringify(&json!(true)).unwrap(), "true".to_string());
+        assert_eq!(stringify(&json!(false)).unwrap(), "false".to_string());
+    }
+
+    #[test]
+    fn stringify_null() {
+        assert_eq!(stringify(&json!(null)).unwrap(), "null".to_string());
+    }
+
+    #[test]
+    fn stringify_invalid() {
+        assert!(stringify(&json!([1])).is_err());
+        assert!(stringify(&json!({"a": 1})).is_err());
+    }
+
+    #[test]
+    fn test_import() -> anyhow::Result<()> {
+        let mut w = test_writer();
+        let mut replica = test_replica();
+
+        let task_json = serde_json::from_value(json!({
+          "id": 0,
+          "description": "repair window",
+          "end": "20211231T175614Z", // TODO (#327)
+          "entry": "20211117T022410Z", // TODO (#326)
+          "modified": "20211231T175614Z",
+          "priority": "M",
+          "status": "completed",
+          "uuid": "fa01e916-1587-4c7d-a646-f7be62be8ee7",
+          "wait": "20211225T001523Z",
+          "due": "20211225T040000Z", // TODO (#82)
+
+          // TODO: recurrence (#81)
+          "imask": 2,
+          "recur": "monthly",
+          "rtype": "periodic",
+          "mask": "+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--",
+
+          // (legacy) UDAs
+          "githubcreatedon": "20211110T175919Z",
+          "githubnamespace": "djmitche",
+          "githubnumber": 228,
+
+          "tags": [
+            "house"
+          ],
+          "depends": [ // TODO (#84)
+            "4f71035d-1704-47f0-885c-6f9134bcefb2"
+          ],
+          "annotations": [
+            {
+              "entry": "20211223T142031Z",
+              "description": "ordered from website"
+            }
+          ],
+          "urgency": 4.16849
+        }))?;
+        import_task(&mut w, &mut replica, &task_json)?;
+
+        let task = replica
+            .get_task(Uuid::parse_str("fa01e916-1587-4c7d-a646-f7be62be8ee7").unwrap())
+            .unwrap()
+            .unwrap();
+        assert_eq!(task.get_description(), "repair window");
+        assert_eq!(task.get_status(), Status::Completed);
+        assert_eq!(task.get_priority(), Priority::M);
+        assert_eq!(
+            task.get_wait(),
+            Some(Utc.ymd(2021, 12, 25).and_hms(00, 15, 23))
+        );
+        assert_eq!(
+            task.get_modified(),
+            Some(Utc.ymd(2021, 12, 31).and_hms(17, 56, 14))
+        );
+        assert!(task.has_tag(&"house".try_into().unwrap()));
+        assert!(!task.has_tag(&"PENDING".try_into().unwrap()));
+        assert_eq!(
+            task.get_annotations().collect::<Vec<_>>(),
+            vec![taskchampion::Annotation {
+                entry: Utc.ymd(2021, 12, 23).and_hms(14, 20, 31),
+                description: "ordered from website".into(),
+            }]
+        );
+        assert_eq!(
+            task.get_legacy_uda("githubcreatedon"),
+            Some("20211110T175919Z")
+        );
+        assert_eq!(task.get_legacy_uda("githubnamespace"), Some("djmitche"));
+        assert_eq!(task.get_legacy_uda("githubnumber"), Some("228"));
+
+        Ok(())
+    }
+}

cli/src/invocation/cmd/mod.rs

@@ -4,6 +4,7 @@ pub(crate) mod add;
 pub(crate) mod config;
 pub(crate) mod gc;
 pub(crate) mod help;
+pub(crate) mod import;
 pub(crate) mod info;
 pub(crate) mod modify;
 pub(crate) mod report;

cli/src/invocation/mod.rs

@@ -90,6 +90,13 @@ pub(crate) fn invoke(command: Command, settings: Settings) -> Result<(), crate::
             return cmd::sync::execute(&mut w, &mut replica, &settings, &mut server);
         }
 
+        Command {
+            subcommand: Subcommand::Import,
+            ..
+        } => {
+            return cmd::import::execute(&mut w, &mut replica);
+        }
+
         Command {
             subcommand: Subcommand::Undo,
             ..