Azure Cosmos DB Python SDK：如何读取更改提要？

Question

This question may be trivial but I cannot figure out how to read change feed using PyDocument DB and the documentation isn't very helpful.

Until now, I've been using native Cosmos DB connector and there I could just set these parameters inside of the config :

"ReadChangeFeed" :
"ChangeFeedQueryName" :
"ChangeFeedStartFromTheBeginning" :
"ChangeFeedUseNextToken" : 
"RollingChangeFeed" :

But the very same options won't work with the Python SDK so I cannot do something like this.

query = client.QueryDocuments(collLink, querystr, options= { 'enableCrossPartitionQuery': True, "ReadChangeFeed" :True})

# Push into list `elements`
elements = list(query)

I have tried to find some samples but unsuccessfully.

Thank you in advance!

Answer 1

Please check our official samples here to read the Change Feed, you can use the QueryItemsChangeFeed method: https://github.com/Azure/azure-cosmos-python/tree/master/samples/ChangeFeedManagement

Here is a snippet:

options = {}
options["startFromBeginning"] = True

response = client.QueryItemsChangeFeed(collection_link, options)
for doc in response:
    print(doc)

Where client is an instance of a Cosmos DB client and collection_link is the name based link to the Collection you want to read, for example dbs/<your-db>/colls/<your-collection> .

startFromBeginning is a flag that will start to read from the beginning of the history of the collection, optionally (also included in the Github sample) is the use of startTime .