cURL fetching an export from API intermittently failing with 500 Internal Server Error

Hi All,

 

We are trying to GET the exports from API but it is intermittently failing. At times when it is successful the response header will have content type returned as "Content-Type: application/octet-stream" and when it fails response header contains "Content-Type: application/json;charset=UTF-8"


FYR see below when it fails with 500:

> GET /2/0/workspaces/{workspaceID}/models/{modelID}/files/{fileID}/ HTTP/1.1
> Host: api.anaplan.com
> User-Agent: curl/7.79.1
> Accept: */*
> authorization: AnaplanAuthToken ***masked***
> Content-Type: application/octet-stream
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 500 Internal Server Error
< Date: Thu, 11 Aug 2022 09:17:47 GMT
< Content-Type: application/json;charset=UTF-8
< Transfer-Encoding: chunked
< Connection: keep-alive
< Cache-Control: no-cache
< Pragma: no-cache
< Expires: 0
< Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
< CF-Cache-Status: DYNAMIC
< Expect-CT: max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"
< X-Content-Type-Options: nosniff
< Server: cloudflare
< CF-RAY: 738fe151dd65756a-LHR


FYR see below when it is success:

> GET /2/0/workspaces/{workspaceID}/models/{modelID}/files/{fileID}/ HTTP/1.1
> Host: api.anaplan.com
> User-Agent: curl/7.79.1
> Accept: */*
> authorization: AnaplanAuthToken ****masked***
> Content-Type: application/octet-stream
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< Date: Thu, 11 Aug 2022 09:17:52 GMT
< Content-Type: application/octet-stream
< Content-Length: 203
< Connection: keep-alive
< Cache-Control: no-cache
< Pragma: no-cache
< Expires: 0
< Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
< CF-Cache-Status: DYNAMIC
< Expect-CT: max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"
< X-Content-Type-Options: nosniff
< Server: cloudflare
< CF-RAY: 738fe16e0bd8779d-LHR

 
This started recently while there are no changes on the script, model ID, workspace ID and file export numbers remains same. Any help or pointers would be greatly appreciated.

Best Answer

Comments

  • Hi @M.Kierepka 

     

    First of all, thank you so much for the response.

     

    Yes we do submit a export action (POST) in our script before requesting the files.

     

    I just ran the script and I see below output where taskState is shown as "IN_PROGRESS", you mean to say we should wait for this taskState to be COMPLETED before we can request (GET) for the files?

    {
      "meta" : {
        "schema" : "https://api.anaplan.com/2/0/models/{modelID}/objects/task"
      },
      "status" : {
        "code" : 200,
        "message" : "Success"
      },
      "task" : {
        "taskId" : "297A9BB774FD4C4787E55EF672B6CA2B",
        "taskState" : "IN_PROGRESS",
        "creationTime" : 1660235336530
      }
    }'

     

     

  • @Sridattam,

    It's not about starting the task - I am sure you are POSTing an export, as in the end you get the file 😉

    What I am referring to (and pasted links to in previous comment) is GET request to the taskID that you get in response to POST. You need to make it (possibly several times) to know if the task is completed. As you observed in original POST response, it was in progress.
    You should almost follow the flow (like here https://www.postman.com/apiplan/workspace/official-anaplan-collection/folder/18986564-71a14979-3d71-4913-af41-4aa95a8c1ad0?ctx=documentation😞

    1. Send POST to request start of action (here export, but can be process/import as well). In the response from server, you should get task ID of this run.
    2. Using just obtained task ID, monitor progress of the task using GETs - waiting can take several seconds, depending on the size of the file. In the response, you will be getting task state, and you need to wait as long as it's in progress.
    3. Once you receive a response that the task has finished (it can be failure for process/import), only then you can download the data (same for process/failure dump for import).

    PS I am an author of still-in-progress API implementation in Python, it might help you understand some processes, here example workflow of export and import (it's naive busy-waiting, you might want to put some breaks between attempts to get the status of the task): https://github.com/DLZaan/apapi/blob/examples/examples/working_with_files.py

    Here is the exact snippet that you might want to inspect:

    def doing(response) -> bool:
        return response.json()["task"]["taskState"] != "COMPLETE"
    
    # run export - you should get task ID, which you can use to monitor the job
    e_task = conn.run_export(t["model_id"], t["export_id"]).json()["task"]["taskId"]
    while doing(tsk := conn.get_export_task(t["model_id"], t["export_id"], e_task)):
    	pass
    # let's check if it was successful
    print(tsk.text)
    if not tsk.json()["task"]["result"]["successful"]:
    	print("Export failed!")
    	return
    print("Export OK - downloading file")
    # we use the fact (undocumented!) that for exports action_id=file_id
    # for **** files: data_out = conn.download_file(t["model_id"], t["export_id"])
    data_out = conn.get_file(t["model_id"], t["export_id"]).content