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Bill_Homan's avatar
Bill_Homan
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Apr 24, 2020

Use F5 REST API Python SDK to update an external datagroup

I have working code using the F5 Python REST SDK that can upload a txt file and create an external datagroup from it.    But I cannot figure out how to use the API to update that datagroup file with...
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Satoshi_Toyosa1's avatar
Satoshi_Toyosa1
Icon for Employee rankEmployee
May 01, 2020

Assuming you have both data-group file object (tmsh list sys file data-group <object>) and external data-group ltm object (tmsh list ltm data-group external <object>), then sending a PATCH request to the file object would override the file contents. The ltm object is just a reference to the file, hence the new data becomes automatically available from iRule.

 

For example,

1) Before the change, the external data-group file contained the following data (see the bottom for the test iRule code)

# Edited for readability
16:02:19 /Common/ExternalDg <HTTP_REQUEST>: {Shota} Short
16:02:19 /Common/ExternalDg <HTTP_REQUEST>: {Ochako} Uravity
16:02:19 /Common/ExternalDg <HTTP_REQUEST>: {Izuku} Deku
16:02:19 /Common/ExternalDg <HTTP_REQUEST>: {Tenya} Ingenium

2) Update the file by calling PATCH /mgmt/tm/sys/file/data-group/<object>.

curl -sku $PASS \
  https://$HOST/mgmt/tm/sys/file/data-group/dg-testMHA.txt \
  -X PATCH -H "Content-type: application/json" \
  -d '{"sourcePath":"http://172.16.10.10/dg-testMHA.txt"}'

where dg-testHMA.txt is the existing file object. Note that the file contains all the records. When the call successfully completes, you will see the following messages in the ltm log:

# Edited. The same messages repeat because I have two TMMs.
16:04:24 tmm1 External Datagroup (/Common/dg-testMHA) queued for update.
16:04:24 tmm  External Datagroup (/Common/dg-testMHA) queued for update.
16:04:25 tmm1 External Datagroup (/Common/dg-testMHA) update finished.
16:04:25 tmm External Datagroup (/Common/dg-testMHA) update finished.

3) Check the data contents again. New data is added.

# Edited. I do not know why the order is different.
16:04:35 /Common/ExternalDg <HTTP_REQUEST>: {Tsuyu} Floppy
16:04:35 /Common/ExternalDg <HTTP_REQUEST>: {Tenya} Ingenium
16:04:35 /Common/ExternalDg <HTTP_REQUEST>: {Ochako} Uravity
16:04:35 /Common/ExternalDg <HTTP_REQUEST>: {Shota} Short
16:04:35 /Common/ExternalDg <HTTP_REQUEST>: {Izuku} Deku

Appendix: Test iRule code

when HTTP_REQUEST {
  foreach {record} [class get dg-testMHA] {
    log local0. "$record"
  }
}

 

  • Bill_Homan's avatar
    Bill_Homan
    Icon for Nimbostratus rankNimbostratus
    May 02, 2020

    Thanks Satoshi! I was able to employ patch as you suggested using this Python code:

     

     

    def update_edg_file(rq, url, fileserver, newfilename, dgfname):
    path = fileserver + "/" + newfilename
    payload = {}
    payload['sourcePath'] = path
 
    req = '{}/sys/file/data-group/{}'.format(url, dgfname)
    resp = rq.patch(req, json.dumps(payload))
    print("update_edg_file, name: {},  PATCH response: {}".format(dgfname, resp))
 
# in main
...
    url_base = 'https://%s/mgmt/tm' % hostname
    rs = requests.session()
    rs.auth = (username, password)
    rs.verify = False
    rs.headers.update({'Content-Type':'application/json'})
    ....
    update_edg_file(rs, url_base, external_file_server, filename, edg_file_name)

    The update is pretty quick.