fix(jobcontroller): better error message if property file not found o…

…n job (#3783)

When we fail to find the props file specified for a titus task we get a cryptic
error message "cannot access first() element of empty list"
Propagate the actual error when the properties file can't be found

clouddriver-titus/src/main/groovy/com/netflix/spinnaker/clouddriver/titus/caching/providers/TitusJobProvider.groovy

@@ -24,6 +24,7 @@ import com.netflix.spinnaker.clouddriver.titus.TitusClientProvider
 import com.netflix.spinnaker.clouddriver.titus.client.TitusClient
 import com.netflix.spinnaker.clouddriver.titus.client.model.Job
 import com.netflix.spinnaker.clouddriver.titus.model.TitusJobStatus
+import com.netflix.spinnaker.kork.web.exceptions.NotFoundException
 import groovy.util.logging.Slf4j
 import okhttp3.OkHttpClient
 import okhttp3.Request
@@ -88,15 +89,13 @@ class TitusJobProvider implements JobProvider<TitusJobStatus> {
       try {
         amazonS3DataProvider.getAdhocData("titus", "${s3.accountName}:${s3.region}:${s3.bucket}", "${s3.key}/${fileName}", outputStream)
       } catch (Exception e) {
-        log.warn("File [${fileName}] does not exist for job [${job.tasks.last().id}].")
-        return null
+        throw new NotFoundException("File [${fileName}] does not exist for job [${job.tasks.last().id}].", e)
       }
       fileContents = new ByteArrayInputStream(outputStream.toByteArray())
     } else {
       Map files = titusClient.logsDownload(job.tasks.last().id)
       if (!files.containsKey(fileName)) {
-        log.warn("File [${fileName}] does not exist for job [${job.tasks.last().id}].")
-        return null
+        throw new NotFoundException("File [${fileName}] does not exist for job [${job.tasks.last().id}].")
       }
       fileContents = client.newCall(new Request.Builder().url(files.get(fileName) as String).build()).execute().body().byteStream()
     }
@@ -113,9 +112,11 @@ class TitusJobProvider implements JobProvider<TitusJobStatus> {
         propertiesFile.load(fileContents)
         results = results << propertiesFile
       }
+
       return results
     }
-    null
+
+    return Collections.emptyMap()
   }
 
   @Override

clouddriver-web/src/main/groovy/com/netflix/spinnaker/clouddriver/controllers/JobController.groovy

@@ -71,14 +71,20 @@ class JobController {
   @ApiOperation(value = "Collect a file from a job", notes = "Collects the file result of a job.")
   @RequestMapping(value = "/{account}/{location}/{id}/{fileName:.+}", method = RequestMethod.GET)
   Map<String, Object> getFileContents(
-                       @ApiParam(value = "Application name", required = true) @PathVariable String application,
-                       @ApiParam(value = "Account job was created by", required = true) @PathVariable String account,
-                       @ApiParam(value = "Namespace, region, or zone job is running in", required = true) @PathVariable String location,
-                       @ApiParam(value = "Unique identifier of job being looked up", required = true) @PathVariable String id,
-                       @ApiParam(value = "File name to look up", required = true) @PathVariable String fileName
+    @ApiParam(value = "Application name", required = true) @PathVariable String application,
+    @ApiParam(value = "Account job was created by", required = true) @PathVariable String account,
+    @ApiParam(value = "Namespace, region, or zone job is running in", required = true) @PathVariable String location,
+    @ApiParam(value = "Unique identifier of job being looked up", required = true) @PathVariable String id,
+    @ApiParam(value = "File name to look up", required = true) @PathVariable String fileName
   ) {
-    jobProviders.findResults {
+    Collection<Map<String, Object>> results = jobProviders.findResults {
       it.getFileContents(account, location, id, fileName)
-    }.first()
+    }
+
+    if (!results.isEmpty()) {
+      return results.first()
+    }
+
+    return Collections.emptyMap()
   }
 }