Hmm yes, it appears that the `airflow connections` CLI doesn't let you create multiple connections of the same conn_id. What the WebUI can do the CLI should be able to do also! It should allow that in some way (behind a `--allow-multiple` flag perhaps? I can see an argument for not allowing set multiple by default as it is often not what people want.)
-ash > On 7 Aug 2018, at 15:17, Deng Xiaodong <[email protected]> wrote: > > Hi Ben, > > If you would like to set multiple connections with the same *conn_id*, you > can only do that in Web UI. That is, you need to build multiple entries > with different host, but with the same *conn_id*. > > The method of setting connection in environment variables can only help set > one connection for each *conn_id*. > > (Of course Web UI stores your connections in the metadata database. So if > you really need to avoid manual interventions and need multiple connections > for one single conn_id, hacking into the metadata database may be an > option? even thought not recommended) > > Other guys please correct me if I'm wrong in any parts. Thanks. > > > Regards, > XD > > On Tue, Aug 7, 2018 at 9:43 PM Ben Laird <[email protected]> wrote: > >> Hello - >> >> I'd like to define multiple connections for the `webhdfs_default` conn_id, >> as we have a primary and backup host for the hadoop namenode. This is for >> use with the WebHDFSHook, which queries for connections and seemingly can >> accept a list of them from the database. >> >> ``` >> nn_connections = self.get_connections(self.webhdfs_conn_id) >> for nn in nn_connections: >> ``` >> >> https://github.com/apache/incubator-airflow/blob/master/airflow/hooks/webhdfs_hook.py#L54-L55 >> >> I can manually add 2 entries for `webhdfs_default` in the Web UI, one for >> each hostname, however with the CLI and adding the entries to the >> airflow.cfg I get errors that a connection already exists. >> >> It seems WebHDFSHook doesn't support reading multiple hosts from one entry. >> Is this a bug? Or is there a different way to accomplish without manually >> adding via the UI? >> >> Thanks! >> Ben Laird >>
