Data Storage cURL interface for v3

Hi,
I have been watching videos on you tube regarding how to download data collected on the server from a device. The video showed (see below) how to collect data with curl, and also had a button to test it. But I see its for version 2, and cant see the same for version 3. Is there a similar thing for V3 ?

Best Regards
Scott

No. But the documentation shows the required cURL commands so you can do it that way.

I’ve altered the most generic & uninformative topic title I’ve ever seen on this forum - please consider that you will get better responses if the volunteers answering can hone in on their areas of expertise.

Hi
Looking at my title it’s not great , having Dyslexia makes my job a bit harder. I have been a software and electronic engineer for over 20 years , and not been easy , but have designed many large systems.

I have looked at the documentation of storage integration and don’t find it as good as earlier versions . I think if I started using it in earlier versions then it would be easier to learn, as there are good articles , and easy to follow. But jumping in at v3 doesn’t make it easier.

Scott

Hi,
I have been trying for a while to read data collected in my account using Storage Integration V3, but not having luck. Just wondering if someone can point me to where I am going wrong?

Below you can see where I activated the storage.
Storage Int1

Below you can see where I setup the Key.
Storage Int2

I have written c code to exectute curl commands as follows (I have used the curl in may applications in the past so know it works), Im not sure about the uplink_message I added below:

 hnd = curl_easy_init();
  if(hnd) {
  struct curl_slist *slist1=NULL;
  slist1 = curl_slist_append(slist1, "Authorization: NSXS.PFEOGHX2SCCZC3Y6VHIOXJELCxxxxxxxxxx");
  slist1 = curl_slist_append(slist1, "Accept: text/event-stream");

  curl_easy_setopt(hnd, CURLOPT_URL, "https://eu1.cloud.thethings.network/api/v3/as/applications/xxxxx/devices/xxxxx/packages/storage/uplink_message:9");

  curl_easy_setopt(hnd, CURLOPT_POSTFIELDS, "limit=10&after=2022-03-29T10:45:49.435171464Z");

  curl_easy_setopt(hnd, CURLOPT_HTTPHEADER, slist1);
  curl_easy_setopt(hnd, CURLOPT_WRITEFUNCTION, got_data);
    ret = curl_easy_perform(hnd);
   
    if(ret != CURLE_OK)
      TRACE("Error");

    curl_easy_cleanup(hnd);

When I run the code it returns:

{“code”:12,“message”:“Not Implemented”}

Any help would be great

Best Regards
Scott

What is the :9 at the end of the URL for?

Have you tried it on the command line as suggested above? See Retrieve Messages | The Things Stack for LoRaWAN

Always best to do the simplest thing first, so leave out the limit & after clauses until you’ve got it working.

If you want something to compare & contrast with, here’s a version in Python: TheThingsStack-Integration-Starters/DataStorage-to-Tab-Python3 at main · descartes/TheThingsStack-Integration-Starters · GitHub

Please do not open a new topic on the same subject. Please do use the tools on the toolbar to format the code so it’s readable - the </> for code - see How do I format my forum post? [HowTo]

Hi
The :9 from the end of the code was a typo.
I removed the “limit=10&after=2022-03-29T10:45:49.435171464Z” from my code , and works fine. I have been trying for a while getting to get the ‘limit’ and ‘after’ to work, but no luck. I have tried using the command line , and checking the documentation, but no luck. I havent done Python, so cant try this. Can anyone let me know how they get these 2 commands to work, with an example?

Best Regards
Scott

Does limit work on its own?

Does after work on its own?

Even if you haven’t “done” Python, you could look at it even if you don’t run it - mostly because that provides a working example …

i did try both on their own as you suggested before, and didnt make a difference. But after looking at the Python, I found the limit and after on the same line as the address , and that worked. I now have:

curl_easy_setopt(hnd, CURLOPT_URL, “https://eu1.cloud.thethings.network/api/v3/as/applications/demoboard/devices/xxx/packages/storage/uplink_message?order=received_at&type=uplink_message&limit=10&after=2022-03-30T12:45:00.000000000Z”);

I see each reading is JSON , and has two characters 10 after each one. Can I assume this always happens? This way I can easily decode each JSON entry between the two characters.

Scott

Curl by default does a post rather than a get - with a -G on the line as per the TTI docs it takes the -d (datas) and appends it to the URL and does a get.

As I’ve not tried curl via a C app this is a subtly that I hadn’t considered. PHP, Python and Javascript for applications, C & C++ (and a bit of Ada) for firmware is more than I can keep track of.

The docs and the various implementations I’ve done don’t have any decimals for seconds. Seems unlikely to cause an issue but just be aware of it. I normally request a small overlap in time and deduplicate as I process because the transfer to the database is buffered - so several minutes can go by without any uplinks being available - I go back 5 minutes. Alternatively use a nice rounded number like on the hour and retrieve about 5 past the hour.

Yes, it’s a minor PitA but it’s due to it being an event stream - which means you can, in theory, open a connection and receive data as it happens. So line 52 of the Python theJSON = "{\"data\": [" + r.text.replace("\n\n", ",")[:-1] + "]}"; removes the two carriage returns.

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