feat: id

Author: apskhem

rust/signed_doc/src/validator/id.rs

@@ -1 +1,92 @@
+//! Validator for Signed Document ID
+
+use std::time::{Duration, SystemTime};
+
+use anyhow::Context;
+
+use crate::{providers::CatalystSignedDocumentProvider, CatalystSignedDocument};
+
+/// Signed Document `id` field validation rule
 pub(crate) struct IdRule;
+
+impl IdRule {
+    /// Validates document `id` field on the timestamps:
+    /// 1. If `provider.future_threshold()` not `None`, document `id` cannot be too far in
+    ///    the future (`future_threshold` arg) from `SystemTime::now()` based on the
+    ///    provide threshold
+    /// 2. If `provider.future_threshold()` not `None`, document `id` cannot be too far
+    ///    behind (`past_threshold` arg) from `SystemTime::now()` based on the provide
+    ///    threshold
+    pub(crate) fn check<Provider>(
+        self,
+        doc: &CatalystSignedDocument,
+        provider: &Provider,
+    ) -> anyhow::Result<bool>
+    where
+        Provider: CatalystSignedDocumentProvider,
+    {
+        let Ok(id) = doc.doc_id() else {
+            doc.report().missing_field(
+                "id",
+                "Cannot get the document field during the field validation",
+            );
+            return Ok(false);
+        };
+
+        let mut is_valid = true;
+
+        let (id_time_secs, id_time_nanos) = id
+            .uuid()
+            .get_timestamp()
+            .ok_or(anyhow::anyhow!("Document id field must be a UUIDv7"))?
+            .to_unix();
+
+        let Some(id_time) =
+            SystemTime::UNIX_EPOCH.checked_add(Duration::new(id_time_secs, id_time_nanos))
+        else {
+            doc.report().invalid_value(
+                    "id",
+                    &id.to_string(),
+                    "Must a valid duration since `UNIX_EPOCH`",
+                    "Cannot instantiate a valid `SystemTime` value from the provided `id` field timestamp.",
+                );
+            return Ok(false);
+        };
+
+        let now = SystemTime::now();
+
+        if let Ok(id_age) = id_time.duration_since(now) {
+            // `now` is earlier than `id_time`
+            if let Some(future_threshold) = provider.future_threshold() {
+                if id_age > future_threshold {
+                    doc.report().invalid_value(
+                        "id",
+                        &id.to_string(),
+                        "id < now + future_threshold",
+                        &format!("Document Version timestamp {id} cannot be too far in future (threshold: {future_threshold:?}) from now: {now:?}"),
+                    );
+                    is_valid = false;
+                }
+            }
+        } else {
+            // `id_time` is earlier than `now`
+            let id_age = now
+                .duration_since(id_time)
+                .context("BUG! `id_time` must be earlier than `now` at this place")?;
+
+            if let Some(past_threshold) = provider.past_threshold() {
+                if id_age > past_threshold {
+                    doc.report().invalid_value(
+                        "id",
+                        &id.to_string(),
+                        "id > now - past_threshold",
+                        &format!("Document Version timestamp {id} cannot be too far behind (threshold: {past_threshold:?}) from now: {now:?}",),
+                    );
+                    is_valid = false;
+                }
+            }
+        }
+
+        Ok(is_valid)
+    }
+}

rust/signed_doc/src/validator/ver.rs

@@ -2,25 +2,27 @@
 
 use crate::CatalystSignedDocument;
 
+/// Signed Document `ver` field validation rule
 pub(crate) struct VerRule;
 
 impl VerRule {
+    /// Validates document `ver` field on the timestamps:
+    /// 1. document `ver` cannot be smaller than document `id` field
     pub(crate) fn check(
         &self,
         doc: &CatalystSignedDocument,
     ) -> anyhow::Result<bool> {
         let Ok(id) = doc.doc_id() else {
             doc.report().missing_field(
                 "id",
-                "Can't get a document id during the validation process",
+                "Cannot get the document field during the field validation",
             );
             return Ok(false);
         };
-
         let Ok(ver) = doc.doc_ver() else {
             doc.report().missing_field(
                 "ver",
-                "Can't get a document ver during the validation process",
+                "Cannot get the document field during the field validation",
             );
             return Ok(false);
         };
@@ -32,9 +34,9 @@ impl VerRule {
                 "ver < id",
                 &format!("Document Version {ver} cannot be smaller than Document ID {id}"),
             );
-            Ok(false)
-        } else {
-            Ok(true)
+            return Ok(false);
         }
+
+        Ok(true)
     }
 }