@lafi_oussama  If I am understanding correctly, this sounds like expected behavior.  You are writing a NiFi Expression Language (NEL) statement to an attribute via your python script so it is not being evaluated by the NEL process. I am not clear on why you are using a python script here anyway. As i understand your use case: 1. NiFi is ingesting files with various filenames. 2. Depending on the filename, you want to add an attr1 attribute to the FlowFile with a specific path value 3. If the filename does not match and value, you want to add an attr1 attribute to FlowFile with value "notfind". This use case can easily be handled by a single UpdateAttribute processor through the use of the "Advanced" functionality without needing to develop and manage a python script. The "Advanced" functionality  works like an If/Then/Else. Would look something like this: Outside the "Advanced" UI is the Else.  Any dynamic attributes add here are added to FlowFile only if the same attribute was NOT added by a rule in the "Advanced" section. So here you set attr1 = "notfind". Inside the "Advanced" section you create one or more rules.  Each rule has a Conditon (If) and an Action (then) sections.  If the condition NEL resolves to "true" then actions are applied to FlowFile.  So you set up a rule for each flowfile filename type. If none of teh rules match then the default attr = notfind is set. If you found any of the suggestions/solutions provided helped you with your issue, please take a moment to login and click "Accept as Solution" on one or more of them that helped. Thank you, Matt ... View more

@lafi_oussama  I am not clear in your ask here. I assume you are using the above NiFi Expression language (NEL) statement in an Update Attribute processor? Assuming the NiFi FlowFile has a filename=blah-OD_NCE-2023.gz ${filename:find('OD_NCE.*.gz') <-- resolves to true :ifElse("/isod/brt_fin_fd_OD_NCE_pipe_sep","notfind")} <-- since above is "true", the if else function would return "/isod/brt_fin_fd_OD_NCE_pipe_sep" and that woud be assigned to the "attr1" attribute on the outbound FlowFile. If your filename does not match your java regular expression "OD_NCE.*.gz" (result in false) would result in attr1 = notfind So I am not clear on what you are asking for: I want to have the value of expression not the string Can you provide an example of what you want to be assigned to FlowFile Attribute "attr1" and what you are actually getting? This info is also not clear to me: I read this expression from file and after this I convert the content to attributes How are you reading expression from file?  What exactly are you reading? Why are you converting FlowFile content to FlowFile attributes?  FlowFile Attributes reside within the NiFi's JVM heap.  So you'll want to avoid this unless absolutely necessary and when you so, only extract the minimum needed. If you found any of the suggestions/solutions provided helped you with your issue, please take a moment to login and click "Accept as Solution" on one or more of them that helped. Thank you, Matt   ... View more

@SowmyaP  The issue is related to the size of source FlowFile content.  It is not related to the volume of FlowFiles being processed, but rather directly related to the individual FlowFile's contemt size.   So only when FlowFile Excel content is larger than 10 MB will you encounter https://issues.apache.org/jira/browse/NIFI-10792. This issue does not exist in Apache NiFi 1.15.3 and earlier. Apache NiFi versions between 1.16 and 1.20 are impacted by this issue. The above issue was addressed in Apache NiFi 1.21.0 and newer. The processor was refactored in above Jira to resolve the 10 MB size restraint. You'll need to upgrade to Apache NiFi 1.21 or newer to resolve this issue. If you found any of the suggestions/solutions provided helped you with your issue, please take a moment to login and click "Accept as Solution" on one or more of them that helped. Thank you, Matt ... View more

@zIfo  The default Single-User-Authorizer (Authorization) and Single-user-provider (authentication) are not intended for production use.  These were added as of  Apache NiFi 1.14 to facilitate a secure out-of-the-box NiFi startup for evaluation and testing.   They provide very basic authentication and authorization. Single user with complete and full access to everything.  So by using this default provider you have no ability to support multiple users with very granular levels of authorization.  The Token on the NiFi server side should expire after 8 hours.  The JWT token stored in the browser may be around longer. You did not share the version of Apache NiFi you have installed, but perhaps the following explains what you are experiencing : https://issues.apache.org/jira/browse/NIFI-9049 But to support NiFi Clusters and NiFi multi-tenant authentication and authorization, you should move to a production ready authentication provider (LDAP commonly used) and authorizer (Managed authorizer commonly used). If you found any of the suggestions/solutions provided helped you with your issue, please take a moment to login and click "Accept as Solution" on one or more of them that helped. Thank you, Matt ... View more

@SowmyaP  You appear to be hitting the following Apache NiFi ConvertExcelToCSVProcessor issue: https://issues.apache.org/jira/browse/NIFI-10792 The fix for above issue exists in the following releases: Apache NiFi 1.21.0 or newer. CFM 2.1.5 SP1 release or newer (https://docs.cloudera.com/cfm/2.1.5/release-notes/topics/cfm-fixed-issues.html) CFM 2.1.6 or newer Upgrading to a newer release should resolve your issue. If you found any of the suggestions/solutions provided helped you with your issue, please take a moment to login and click "Accept as Solution" on one or more of them that helped. Thank you, Matt ... View more

@samrathal  Apache NiFi has hardcoded return size to 100: https://github.com/apache/nifi/blob/main/nifi-nar-bundles/nifi-framework-bundle/nifi-framework/nifi-web/nifi-web-api/src/main/java/org/apache/nifi/web/dao/impl/StandardConnectionDAO.java#L361 I am sure this was originally done for performance and NiFi JVM heap usage reasons. The first 100 returned should be the oldest 100 in queue (keeping in mind that a connection will also show count of FlowFiles pending processing by downstream processor and count of those currently allocated to a downstream component process.  The listing only returns those pending FlowFiles and not those already owned by downstream component).What is the use case for needing to list more?  Ideally what is found in a queue should be changing rapidly, so expectation is that each listing request would be different. Listing a queue does not stop NiFi processing.  The intent is not for NiFi to ever hold FlowFiles in any connection.   So using API to  poll connection for FlowFile listings seems odd to me.  What is returned by that listing could be inaccurate milliseconds later. Also be careful with your API requests.  When a listing is performed through the browser three different request are made. 1. First listing-request is made and replicated to all nodes to get result sets.   2. Return from step 1 request gives the ID for the generated listing request being held in heap memory.  That ID is used to fetch the results in that specific listing ID 3. A DELETE request is made to remove the listing with that ID from NiFi.   *** When using API, If steps 1 and 2 are all that are being executed, the various listing request(s) will stay in heap memory. If you found any of the suggestions/solutions provided helped you with your issue, please take a moment to login and click "Accept as Solution" on one or more of them that helped. Thank you, Matt ... View more