read meta-url from variable

[sedlund]

What would you like to be added:

juicefs cli should read meta-url from an environment variable by if set.
I suggest JFS_URL

If the meta-url is specified on the command line, it should take precedence.

Why is this needed:

it makes the cli nicer to use not having to specify the url each time it is required.

[solracsf]

Agree, but it would make more sense to be META_URL, as META_PASSWORD already exists.

[sedlund]

agree, would like to see all juicefs variables prefixed as is common elsewhere -- JFS_ or JUICEFS_

[suzaku]

So if I run juicefs mount xxx, xxx would be interpreted as the mount point while the URL is read from the environment variable?
What if I only specify the URL and miss the mount point?

[sedlund]

So if I run juicefs mount xxx, xxx would be interpreted as the mount point while the URL is read from the environment variable?

Yes. If $JUICEFS_META_URL is set, it fits a validation schema and xxx is a directory.

What if I only specify the URL and miss the mount point?

Following the same steps above, the URL fits validation URL schema then it will error on no mount point specified.

[davies]

It's better to keep the command arguments consistent.

The sync command read the meta-url from environment variable, which use the volume name as the name, for example,

myfs=redis://localhost/  juicefs sync jfs://myfs/prefix s3://mybucket/prefix

It support multiple volumes in the same time, maybe we can do the same thing here:

myjfs=redis://localhost/  juicefs mount myjfs /mnt

But, we use redis:// as the default schema, and the myjfs will be treated as hostname rather than a variable name.