[pbs-devel] [PATCH proxmox-backup] fix #4301: correctly pass rate limit parameters to API

[Stefan Hanreich]

On 10/20/22 16:06, Wolfgang Bumiller wrote:
> On Thu, Oct 20, 2022 at 03:50:59PM +0200, Stefan Hanreich wrote:
>>
>>
>> On 10/20/22 15:44, Wolfgang Bumiller wrote:
>>> On Thu, Oct 20, 2022 at 02:59:46PM +0200, Stefan Hanreich wrote:
>>>>
>>>>
>>>> On 10/20/22 14:48, Wolfgang Bumiller wrote:
>>>>> On Thu, Oct 20, 2022 at 01:37:31PM +0200, Stefan Hanreich wrote:
>>>>>> With the old code the rate limit parameters got passed in their own
>>>>>> dictionary under the limit key, but the API expects the rate-limit
>>>>>> settings as top-level keys. This commit correctly sets the rate-limit
>>>>>> parameters so the API actually uses them.
>>>>>>
>>>>>> Signed-off-by: Stefan Hanreich <s.hanreich at proxmox.com>
>>>>>> ---
>>>>>>     src/bin/proxmox-backup-manager.rs | 14 ++++++++++++--
>>>>>>     1 file changed, 12 insertions(+), 2 deletions(-)
>>>>>>
>>>>>> diff --git a/src/bin/proxmox-backup-manager.rs b/src/bin/proxmox-backup-manager.rs
>>>>>> index 58e7e33a..cdd1037d 100644
>>>>>> --- a/src/bin/proxmox-backup-manager.rs
>>>>>> +++ b/src/bin/proxmox-backup-manager.rs
>>>>>> @@ -2,7 +2,7 @@ use std::collections::HashMap;
>>>>>>     use std::io::{self, Write};
>>>>>>     use std::str::FromStr;
>>>>>> -use anyhow::Error;
>>>>>> +use anyhow::{Error, format_err};
>>>>>>     use serde_json::{json, Value};
>>>>>>     use proxmox_router::{cli::*, RpcEnvironment};
>>>>>> @@ -297,7 +297,6 @@ async fn pull_datastore(
>>>>>>             "store": store,
>>>>>>             "remote": remote,
>>>>>>             "remote-store": remote_store,
>>>>>> -        "limit": limit,
>>>>>>         });
>>>>>>         if remote_ns.is_some() {
>>>>>> @@ -320,6 +319,17 @@ async fn pull_datastore(
>>>>>>             args["remove-vanished"] = Value::from(remove_vanished);
>>>>>>         }
>>>>>> +    let args_map = args
>>>>>> +        .as_object_mut()
>>>>>> +        .ok_or_else(|| format_err!("args is not an Object"))?;
>>>>>
>>>>> ^ We create the `args` map only a few lines further up, so it would be
>>>>> fine to just `.unwrap()` here. And it would be nicer to keep the access
>>>>> short (iow move the `.as_object_mut()` down to where it's used for `.append()`)
>>>>>
>>>>
>>>> Can replace it with unwrap(), shouldn't be a problem.
>>>>
>>>> The reason why I stored it in a variable was that with a subsequent patch I
>>>> will also append another map to the args, but I could then just call
>>>> .as_object_mut() twice, what do you think?
>>>
>>> I suppose that's fine. If you already know such things while sending a
>>> patch without the followups being part of the same series, you can note
>>> such things after the `---` in the patch mail, that way it won't
>>> needlessly end up in the commit message, but still be visible to the
>>> reviewer.
>>>
>>> Come to think of it, there are a lot of `args[key] = value;` assignments
>>> which could probably benefit from already having the `&mut Map` instead
>>> of the `Value` enum.
>>>
>>> Maybe should change it like this
>>>
>>>       -    let mut args = json!(...)
>>>       +    let mut args_value = json(!...);
>>>       +    let args = args_value.as_object_mut().unwrap();
>>>
>>> right where it is created, this way the unwrap will stay even closer to
>>> the creation, the remaining assignments already see the object type, and
>>> you can call append, too.
>>> Finally, the `Some(args)` would need to be changed to `Some(args_value)`
>>> in the `post()` call.
>>>
>>
>> I will keep that in mind for future patches, thanks for the info!
>>
>> The problem is when assigning via args[key] = value on a Map, it actually
>> panics if the key doesn't exist in the map [1], so I'm afraid this isn't a
>> possibility unless I'm missing something.
> 
> Can be changed to use `.insert()` ;-)

yes, but I thought that would just be needlessly verbose since all 
`args[key] = value` would be replaced with some kind of

```
args.insert(
   key.to_string(),
   value.into() / json!(value)
);
```

I can definitely change it to use `insert()` in my subsequent patch if 
you want me to - just say the word ;)