Fix: Devcontainer Index - Add Error Context (#16)

* Split parsing a collection to improve error context.
* list: Avoid displaying empty collection table.

Author: CodeMan99

src/list.rs

@@ -22,37 +22,41 @@ fn collection_templates_and_features(oci_reference: &str, collection: &Collectio
     println!("Repository:    {}", &source_information.repository);
     println!("OCI Reference: {}", &source_information.oci_reference);
 
-    let search_results = {
-        let features = collection.features.iter().map(search::SearchResult::from);
-        let templates = collection.templates.iter().map(search::SearchResult::from);
-        features.chain(templates)
-    };
-    let data: Vec<[String; 5]> = search_results
-        .enumerate()
-        .map(|(i, r)| {
-            let description = r
-                .description
-                .as_ref()
-                .and_then(|d| d.lines().next())
-                .unwrap_or_default();
-            [
-                (i + 1).to_string(),
-                r.collection.to_string(),
-                r.id.replace(oci_reference, "~"),
-                r.name.to_string(),
-                description.to_string(),
-            ]
-        })
-        .collect();
-    let mut table = ascii_table::AsciiTable::default();
-
-    table.column(0).set_align(ascii_table::Align::Right);
-    table.column(1).set_header("Type");
-    table.column(2).set_header("OCI Reference");
-    table.column(3).set_header("Name").set_max_width(40);
-    table.column(4).set_header("Description").set_max_width(75);
-
-    table.print(data);
+    let count = collection.features.len() + collection.templates.len();
+
+    if count > 0 {
+        let search_results = {
+            let features = collection.features.iter().map(search::SearchResult::from);
+            let templates = collection.templates.iter().map(search::SearchResult::from);
+            features.chain(templates)
+        };
+        let data: Vec<[String; 5]> = search_results
+            .enumerate()
+            .map(|(i, r)| {
+                let description = r
+                    .description
+                    .as_ref()
+                    .and_then(|d| d.lines().next())
+                    .unwrap_or_default();
+                [
+                    (i + 1).to_string(),
+                    r.collection.to_string(),
+                    r.id.replace(oci_reference, "~"),
+                    r.name.to_string(),
+                    description.to_string(),
+                ]
+            })
+            .collect();
+        let mut table = ascii_table::AsciiTable::default();
+
+        table.column(0).set_align(ascii_table::Align::Right);
+        table.column(1).set_header("Type");
+        table.column(2).set_header("OCI Reference");
+        table.column(3).set_header("Name").set_max_width(40);
+        table.column(4).set_header("Description").set_max_width(75);
+
+        table.print(data);
+    }
 }
 
 fn overview_collections(index: &DevcontainerIndex) {

src/registry.rs

@@ -473,18 +473,50 @@ pub fn read_devcontainer_index<P: AsRef<Path>>(filename: P) -> Result<Devcontain
             |arr| {
                 let parsed = arr
                     .iter()
-                    // TODO: Skip errors of a single feature or template, not the entire collection
-                    .filter_map(|value| match serde_json::from_value::<Collection>(value.to_owned()) {
-                        Ok(collection) => {
-                            features_count += collection.features.len();
-                            templates_count += collection.templates.len();
-                            Some(collection)
-                        },
-                        Err(_) => {
-                            // TODO: parse the collection fields so that source_information can be displayed here.
-                            log::warn!("Skipping collection due to parsing error");
-                            None
-                        },
+                    .filter_map(|value| {
+                        let source_information: SourceInformation = value
+                            .get("sourceInformation")
+                            .and_then(|value| serde_json::from_value(value.to_owned()).ok())?;
+                        let features = value.get("features").and_then(|value| value.as_array())?;
+                        let features = features
+                            .iter()
+                            .flat_map(|value| match serde_json::from_value::<Feature>(value.to_owned()) {
+                                Ok(feature) => {
+                                    features_count += 1;
+                                    Some(feature)
+                                },
+                                Err(_) => {
+                                    log::warn!(
+                                        "Skipping feature due to parsing error. Collection.oci_ref = {}",
+                                        &source_information.oci_reference
+                                    );
+                                    None
+                                },
+                            })
+                            .collect();
+                        let templates = value.get("templates").and_then(|value| value.as_array())?;
+                        let templates = templates
+                            .iter()
+                            .flat_map(|value| match serde_json::from_value::<Template>(value.to_owned()) {
+                                Ok(template) => {
+                                    templates_count += 1;
+                                    Some(template)
+                                },
+                                Err(_) => {
+                                    log::warn!(
+                                        "Skipping template due to parsing error. Collection.oci_ref = {}",
+                                        &source_information.oci_reference
+                                    );
+                                    None
+                                },
+                            })
+                            .collect();
+
+                        Some(Collection {
+                            source_information,
+                            features,
+                            templates,
+                        })
                     })
                     .collect();