Check if a record exists using the API

1

Hello all

Using the API (both REST and RPC), I’m trying to import users from a JSON file. However I only want to create new users if they do not already exist. I’m trying to figure out which is the most efficient way of checking whether a user (and more generically any record) exists.

I notice that the RPC method frappe.client.get does not throw an error when the record does not exist and returns a JSON object with a top-level key:value pair of “exc_type”:“DoesNotExistError”

curl -s -H "${cHA}" -H "${cHC}" -H "${cHT}" -G ${cUM}frappe.client.get -d 'doctype=User' -d 'name=Admin'

which returns

{"exc_type":"DoesNotExistError","_server_messages":"[\"{\\\"message\\\": \\\"User Admin not found\\\",...

and when the user does exist (eg Administrator, not Admin), the return then is also a JSON object but with a top level key of “message”.

{"message":{"name":"Administrator",...

Currently I use this differentiation on the top-level key to determine whether the record exists or not, before I invoke the REST call to create a new user, but it feels very convoluted and I somehow believe there should be a more efficient way of doing it.

What does the experts recommend?

2

Here’s how I do it:

declare HOST="dev.erpnext.host"
declare AUTH_TOKEN="Authorization: token 21???????????1d:10???????????ee"
declare RESULT=/tmp/result.log

declare USER="Administrator"
declare HTTP_CODE=$(curl -w "%{http_code}" -s -o ${RESULT} "https://${HOST}/api/resource/User/${USER}" -H "${AUTH_TOKEN}");
if [[ ${HTTP_CODE} -eq 200 ]]; then cat ${RESULT} | jq -r '.data.name'; else echo -e "Uh oh! [${HTTP_CODE}]"; fi;

Returns …

Administrator

declare USER="Admin"
declare HTTP_CODE=$(curl -w "%{http_code}" -s -o ${RESULT} "https://${HOST}/api/resource/User/${USER}" -H "${AUTH_TOKEN}");
if [[ ${HTTP_CODE} -eq 200 ]]; then cat ${RESULT} | jq -r '.data.name'; else echo -e "Uh oh! [${HTTP_CODE}]"; fi;

Returns…

Uh oh! [404]

Set the first two environment variables correctly, and the following commands ought to serve you with no other edits needed.

curl switches:

  • -w return only the indicated parts of the HTTP Response
  • -s silent mode
  • -o send output to the indicated file

jq switches:

  • -r output valid quoted JSON.

However

I bitterly regret ever using shell scripting for configuring an ERPNext site!

Don’t do it!

I have an unmanageable mess of scripts in which everything is 10 times harder to do than it would be in Python.

Recently, I created a setup app that I install as soon as I have a working ERPNext instance.

Instead of slowly pushing data in through the API, I call a whitelisted method on my app that reaches out and pulls in the data I want to load. Programming is easier, cleaner, understandable, maintainable … and fast!

def install_widgets(company):
    LG("Getting values for company :: {}".format(company))
    prepareGlobals(company)

    prepareTemporaryTables()

    LOG("\n\nLoad {} warehouses.".format(NAME_COMPANY))

      :      :      :      :      :      :      :

For shorties

@frappe.whitelist()
def installwidgets(company):
    return install_widgets(company)

For large batches that time out

@frappe.whitelist()
def queueInstallStockEntries(company):
    frappe.enqueue(
        'setup.setup.doctype.setup.widget.install_stock_entries',
        company=company, is_async=True, timeout=240000)
    return "Enqueued"
1 Like
3

Ah @MartinHBramwell , this is precisely what I thought I’d get from you : A well constructed, in-depth answer. Thanks so much for your contributions on this forum :laughing:

1 Like
4

Yeah! It’s called “Obsessive Compulsive Disorder”, but it has its benefits.

5

Can you share what you use frappe Api’s for?

I’m studying coding and would to hear real world examples.

6

I use it for importing data from a legacy system.

I prepare initial examples in Postman, trimming the POST bodies down to the minimum required set of attributes then reformat the output of the legacy system to the corresponding JSON.

I can then iterate the JSON, calling the API for each Item, in which ever language suits the moment JS, Python, shell, etc.