From 2eca43e175c97a5161b837dcce90ac420522c557 Mon Sep 17 00:00:00 2001
From: mvdbeek <m.vandenbeek@gmail.com>
Date: Mon, 27 Nov 2023 14:50:28 +0100
Subject: [PATCH] Allow expression evaluation to fail, so default value can be
 set in expression

---
 .../tools/parameters/dynamic_options.py       | 16 ++++++++------
 test/functional/tools/select_from_url.xml     | 21 ++++++++++++++++++-
 2 files changed, 30 insertions(+), 7 deletions(-)

diff --git a/lib/galaxy/tools/parameters/dynamic_options.py b/lib/galaxy/tools/parameters/dynamic_options.py
index 6f63eca658d..afa1bf588c3 100644
--- a/lib/galaxy/tools/parameters/dynamic_options.py
+++ b/lib/galaxy/tools/parameters/dynamic_options.py
@@ -788,16 +788,20 @@ class DynamicOptions:
             try:
                 response = requests.get(url)
                 response.raise_for_status()
+                data = response.json()
             except Exception as e:
                 log.warning("Fetching from url '%s' failed: %s", url, str(e))
-                return []
-            data = response.json()
+                data = None
 
             if self.from_url_postprocess:
-                data = do_eval(
-                    self.from_url_postprocess,
-                    data,
-                )
+                try:
+                    data = do_eval(
+                        self.from_url_postprocess,
+                        data,
+                    )
+                except Exception as eval_error:
+                    log.warning("Failed to evaluate postprocess_expression: %s", str(eval_error))
+                    data = []
 
             # We only support the very specific ["name", "value", "selected"] format for now.
             return [to_triple(d) for d in data]
diff --git a/test/functional/tools/select_from_url.xml b/test/functional/tools/select_from_url.xml
index 30567392419..260b239dc90 100644
--- a/test/functional/tools/select_from_url.xml
+++ b/test/functional/tools/select_from_url.xml
@@ -1,7 +1,8 @@
 <tool id="select_from_url" name="select_from_url" version="0.1.0" profile="23.1">
     <command><![CDATA[
 echo '$url_param_value' > '$param_value' &&
-echo '$url_param_value_postprocessed' > '$param_value_postprocessed'
+echo '$url_param_value_postprocessed' > '$param_value_postprocessed' &&
+echo '$invalid_url_param_value_postprocessed' > '$invalid_param_value_postprocessed'
     ]]></command>
     <inputs>
         <param name="url_param_value" type="select">
@@ -21,15 +22,28 @@ echo '$url_param_value_postprocessed' > '$param_value_postprocessed'
                 ]]></postprocess_expression>
             </options>
         </param>
+        <param name="invalid_url_param_value_postprocessed" type="select">
+            <options from_url="https://usegalaxy.or/api/genomes/dm6">
+                <postprocess_expression type="ecma5.1"><![CDATA[${
+                    if (inputs) {
+                        return Object.values(inputs.chrom_info).map((v) => [v.chrom, v.len])
+                    } else {
+                        return [["The fallback value", "default"]]
+                    }
+                }]]></postprocess_expression>
+            </options>
+        </param>
     </inputs>
     <outputs>
         <data format="txt" label="url param value" name="param_value"></data>
         <data format="txt" label="url param value postprocessed" name="param_value_postprocessed"></data>
+        <data format="txt" label="invalid url param value postprocessed" name="invalid_param_value_postprocessed"></data>
     </outputs>
     <tests>
         <test>
             <param name="url_param_value" value="dm6" />
             <param name="url_param_value_postprocessed" value="chr2L" />
+            <param name="invalid_url_param_value_postprocessed" value="default" />
             <output name="param_value">
                 <assert_contents>
                     <has_text text="dm6"></has_text>
@@ -40,6 +54,11 @@ echo '$url_param_value_postprocessed' > '$param_value_postprocessed'
                     <has_text text="23513712"></has_text>
                 </assert_contents>
             </output>
+            <output name="invalid_param_value_postprocessed">
+                <assert_contents>
+                    <has_text text="default"></has_text>
+                </assert_contents>
+            </output>
         </test>
     </tests>
 </tool>