Support new EMDB API for EM volume contour levels

CHANGELOG.md

@@ -16,6 +16,7 @@ Note that since we don't clearly distinguish between a public and private interf
 - Fix `includeParent` support for multi-instance bond visuals.
 - Add `operator` Loci granularity, selecting everything with the same operator name.
 - Prefer ``_label_seq_id`` fields in secondary structure assignment.
+- Support new EMDB API (https://www.ebi.ac.uk/emdb/api/entry/map/[EMBD-ID]) for EM volume contour levels.
 
 ## [v2.1.0] - 2021-07-05
 

src/mol-plugin/behavior/dynamic/volume-streaming/util.ts

@@ -76,8 +76,22 @@ export async function getContourLevelEmdb(plugin: PluginContext, taskCtx: Runtim
 }
 
 export async function getContourLevelPdbe(plugin: PluginContext, taskCtx: RuntimeContext, emdbId: string) {
+    // TODO: parametrize URL in plugin settings?
+    emdbId = emdbId.toUpperCase();
+    const header = await plugin.fetch({ url: `https://www.ebi.ac.uk/emdb/api/entry/map/${emdbId}`, type: 'json' }).runInContext(taskCtx);
+    const contours = header?.map?.contour_list?.contour;
+
+    if (!contours || contours.length === 0) {
+        // try fallback to the old API
+        return getContourLevelPdbeLegacy(plugin, taskCtx, emdbId);
+    }
+
+    return contours.find((c: any) => c.primary)?.level ?? contours[0].level;
+}
+
+async function getContourLevelPdbeLegacy(plugin: PluginContext, taskCtx: RuntimeContext, emdbId: string) {
+    // TODO: parametrize URL in plugin settings?
     emdbId = emdbId.toUpperCase();
-    // TODO: parametrize to a differnt URL? in plugin settings perhaps
     const header = await plugin.fetch({ url: `https://www.ebi.ac.uk/pdbe/api/emdb/entry/map/${emdbId}`, type: 'json' }).runInContext(taskCtx);
     const emdbEntry = header?.[emdbId];
     let contourLevel: number | undefined = void 0;