Merge pull request #5 from projectpythia-mystmd/agoose77/feat-improve…

…-error-handling

ENH: improve error handling

pythia-gallery.mjs

@@ -1,8 +1,7 @@
-import { spawn } from 'node:child_process';
-
+import { spawn } from "node:child_process";
 
 /**
- * Call out to an external process that conforms to a JSON-based 
+ * Call out to an external process that conforms to a JSON-based
  * stdin-stdout transform specification.
  *
  * @param opts transform options, containing the binary path and arguments
@@ -17,17 +16,31 @@ function externalTransform(opts) {
     subprocess.stdin.end();
 
     // Read out the response in chunks
-    const buffers = [];
-    subprocess.stdout.on('data', (chunk) => {
-      buffers.push(chunk);
+    const stdoutBuffers = [];
+    subprocess.stdout.on("data", (chunk) => {
+      stdoutBuffers.push(chunk);
+    });
+    const stderrBuffers = [];
+    subprocess.stderr.on("data", (chunk) => {
+      stderrBuffers.push(chunk);
     });
 
     // Await exit
-    await new Promise((resolve) => {
-      subprocess.on('close', resolve);
+    const exitCode = await new Promise((resolve) => {
+      subprocess.on("close", (code) => resolve(code));
     });
+    if (exitCode) {
+      const stderr = Buffer.concat(stderrBuffers).toString();
+      throw new Error(
+        `Non-zero error code while running pythia-gallery'\n\n${stderr}`,
+      );
+    } else if (stderrBuffers.length) {
+      const stderr = Buffer.concat(stderrBuffers).toString();
+      // Log the error
+      console.debug(`\n\n${stderr}\n\n`);
+    }
     // Concatenate the responses
-    const stdout = Buffer.concat(buffers).toString();
+    const stdout = Buffer.concat(stdoutBuffers).toString();
 
     // Modify the tree in-place
     const result = JSON.parse(stdout);
@@ -36,23 +49,23 @@ function externalTransform(opts) {
 }
 
 const cookbooksTransform = () =>
-  externalTransform({ executable: 'python3', args: ['pythia-gallery.py'] });
+  externalTransform({ executable: "python3", args: ["pythia-gallery.py"] });
 
 const pythiaGalleryDirective = {
-  name: 'pythia-cookbooks',
-  doc: 'An example directive for embedding a Pythia cookbook gallery.',
+  name: "pythia-cookbooks",
+  doc: "An example directive for embedding a Pythia cookbook gallery.",
   run() {
-    const img = { type: 'pythia-cookbooks', children: [] };
+    const img = { type: "pythia-cookbooks", children: [] };
     return [img];
   },
 };
 const pythiaGalleryTransform = {
   plugin: cookbooksTransform,
-  stage: 'document',
+  stage: "document",
 };
 
 const plugin = {
-  name: 'Pythia Gallery',
+  name: "Pythia Gallery",
   directives: [pythiaGalleryDirective],
   transforms: [pythiaGalleryTransform],
 };

pythia-gallery.py

@@ -3,6 +3,7 @@
 import urllib.request
 import yaml
 import concurrent.futures
+import traceback
 
 from unist import *
 
@@ -23,60 +24,65 @@
 
 
 def fetch_yaml(url: str):
+    print(f"Fetching {url}", file=sys.stderr, flush=True)
     with urllib.request.urlopen(url) as response:
         body = response.read().decode()
     return yaml.load(body, yaml.SafeLoader)
 
 
 def render_cookbook(name: str):
-    raw_base_url = f"https://raw.githubusercontent.com/ProjectPythia-MystMD/{name}/main"
-    base_url = f"https://github.com/ProjectPythia-MystMD/{name}"
-    config_url = f"{raw_base_url}/_config.yml"
-    book_url = f"https://projectpythia-mystmd.github.io/{name}"
-
-    # Load JB data
-    data = fetch_yaml(config_url)
-    title = data["title"]
-
-    # Fetch gallery metadata
-    gallery_url = f"{raw_base_url}/_gallery_info.yml"
-    gallery_data = fetch_yaml(gallery_url)
-    image_name = gallery_data["thumbnail"]
-    image_url = f"{raw_base_url}/{image_name}"
-
-    # Build tags
-    tags = gallery_data["tags"]
-
-    return {
-        "type": "card",
-        "url": book_url,
-        "children": [
-            {"type": "cardTitle", "children": [text(title)]},
-            div(
-                [
-                    image(image_url),
-                    div(
-                        [
-                            span(
-                                [text(item)],
-                                style=styles.get(name, DEFAULT_STYLE),
-                            )
-                            for name, items in tags.items()
-                            if items is not None
-                            for item in items
-                        ]
-                    ),
-                ],
-            ),
-        ],
-    }
-
+    try:
+        print(f"Rendering {name}", file=sys.stderr, flush=True)
+        raw_base_url = f"https://raw.githubusercontent.com/ProjectPythia-MystMD/{name}/main"
+        config_url = f"{raw_base_url}/myst.yml"
+        book_url = f"https://projectpythia-mystmd.github.io/{name}"
+
+        # Load JB data
+        config = fetch_yaml(config_url)
+        title = config["project"]["title"]
+
+        # Fetch gallery metadata
+        gallery_url = f"{raw_base_url}/_gallery_info.yml"
+        gallery_data = fetch_yaml(gallery_url)
+        image_name = gallery_data["thumbnail"]
+        image_url = f"{raw_base_url}/{image_name}"
+
+        # Build tags
+        tags = gallery_data["tags"]
+
+        return {
+            "type": "card",
+            "url": book_url,
+            "children": [
+                {"type": "cardTitle", "children": [text(title)]},
+                div(
+                    [
+                        image(image_url),
+                        div(
+                            [
+                                span(
+                                    [text(item)],
+                                    style=styles.get(name, DEFAULT_STYLE),
+                                )
+                                for name, items in tags.items()
+                                if items is not None
+                                for item in items
+                            ]
+                        ),
+                    ],
+                ),
+            ],
+        }
+    except Exception as err:
+        print(f"\n\nError rendering {name}", file=sys.stderr)
+        traceback.print_exception(err, file=sys.stderr)
+        return None
 
 def render_cookbooks(pool):
     with open("cookbook_gallery.txt") as f:
         body = f.read()
 
-    return [*pool.map(render_cookbook, body.splitlines())]
+    return [c for c in pool.map(render_cookbook, body.splitlines()) if c is not None]
 
 
 if __name__ == "__main__":