Hi folks I am trying to schedule a flow to run every 4th bus

Question

Hi folks I am trying to schedule a flow to run every 4th business day so I created my own filter function following a similar format as how prefect schedule filter functions are implemented but I am getting a marshmallow exceptions ValidationError

Marwan Sarieddine · Answer

Here is my implementation ```def is fourth business day provided date datetime gt Callable datetime bool Filter that allows events occuring on the fourth business day between 2020 and 2050 Args dt datetime the datetime to match Returns Callable datetime bool a filter function def filter fn dt datetime gt bool dates = pd Series pd bdate range 2020 01 01 2050 01 01 valid dates = dates groupby dates dt year dates dt month nth 4 dt date to numpy return dt date in valid dates return filter fn```

Marwan Sarieddine · Answer

Here is the error I am getting ``` etl embs ~ infima etl mirror embs adjust mirror flow frequency python register py Traceback most recent call last File register py line 299 in lt module gt register flow File register py line 292 in register flow flow register params File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages prefect core flow py line 1608 in register registered flow = client register File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages prefect client client py line 734 in register serialized flow = flow serialize build=build type Any File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages prefect core flow py line 1445 in serialize serialized = schema exclude= storage dump flow copy File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow schema py line 557 in dump result = self serialize processed obj many=many File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow schema py line 521 in serialize value = field obj serialize attr name obj accessor=self get attribute File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow fields py line 316 in serialize return self serialize value attr obj kwargs File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow fields py line 571 in serialize return schema dump nested obj many=many File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow oneofschema one of schema py line 72 in dump result = result data = self dump obj kwargs File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow oneofschema one of schema py line 107 in dump result = schema dump obj many=False kwargs File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow schema py line 557 in dump result = self serialize processed obj many=many File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow schema py line 521 in serialize value = field obj serialize attr name obj accessor=self get attribute File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow fields py line 316 in serialize return self serialize value attr obj kwargs File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow fields py line 704 in serialize return self inner serialize each attr obj kwargs for each in value File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages marshmallow fields py line 704 in lt listcomp gt return self inner serialize each attr obj kwargs for each in value File Users marwansarieddine pyenv versions 3 8 5 envs etl embs lib python3 8 site packages prefect utilities serialization py line 397 in serialize raise ValidationError Invalid function reference format value marshmallow exceptions ValidationError Invalid function reference lt function is fourth business day at 0x120a0e790 gt ```

Jim Crist-Harif · Answer

Sorry cloud doesn t accept custom scheduler filters since the filters run on our infrastructure

Jim Crist-Harif · Answer

We should be able to provide a better error message than that I ll open an issue

Marwan Sarieddine · Answer

I see thank you for your quick response

Marwan Sarieddine · Answer

so there is now way I can schedule a flow for every 4th business day using cloud

Jim Crist-Harif · Answer

Every 4th business day is an interesting schedule can you open an issue describing your use case so we can figure out what other builtins we d need to add to make this possible

Jim Crist-Harif · Answer

Right now I see a way to run a flow every 4th day run a flow every 4th day excluding non business days but not every 4th business day

Marwan Sarieddine · Answer

I see ok will try to open up an issue soon describing our usecase

Marwan Sarieddine · Answer

Please see <https github com PrefectHQ prefect issues 3501> for the issue post