the CLI should fail gracefully when tahoe: doesn't exist and no alias is specified

[kevan]

When I do 'tahoe ls' on a fresh node, I get

kevan@b8chem-87:~$ tahoe ls
Traceback (most recent call last):
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/support/bin/tahoe", line 8, in <module>
    load_entry_point('allmydata-tahoe==1.6.0', 'console_scripts', 'tahoe')()
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/src/allmydata/scripts/runner.py", line 102, in run
    rc = runner(sys.argv[1:])
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/src/allmydata/scripts/runner.py", line 89, in runner
    rc = cli.dispatch[command](so)
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/src/allmydata/scripts/cli.py", line 429, in list
    rc = tahoe_ls.list(options)
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/src/allmydata/scripts/tahoe_ls.py", line 18, in list
    rootcap, path = get_alias(aliases, where, DEFAULT_ALIAS)
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/src/allmydata/scripts/common.py", line 150, in get_alias
    return aliases[default], path
KeyError: 'tahoe'
kevan@b8chem-87:~$ 

If I create an alias, then try again, I get

kevan@b8chem-87:~$ tahoe create-alias havasu
Alias 'havasu' created
kevan@b8chem-87:~$ tahoe ls
Traceback (most recent call last):
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/support/bin/tahoe", line 8, in <module>
    load_entry_point('allmydata-tahoe==1.6.0', 'console_scripts', 'tahoe')()
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/src/allmydata/scripts/runner.py", line 102, in run
    rc = runner(sys.argv[1:])
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/src/allmydata/scripts/runner.py", line 89, in runner
    rc = cli.dispatch[command](so)
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/src/allmydata/scripts/cli.py", line 429, in list
    rc = tahoe_ls.list(options)
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/src/allmydata/scripts/tahoe_ls.py", line 18, in list
    rootcap, path = get_alias(aliases, where, DEFAULT_ALIAS)
  File "/home/kevan/Desktop/software/tahoe/allmydata-tahoe-1.6.0/src/allmydata/scripts/common.py", line 150, in get_alias
    return aliases[default], path
KeyError: 'tahoe'
kevan@b8chem-87:~$ 

I should probably see something like

kevan@b8chem-87:~$ tahoe ls
Usage:  tahoe <command> [command options] ls [options]
Options:
  -q, --quiet             Operate silently.
  -V, --version           Display version numbers and exit.
      --version-and-path  Display version numbers and paths to their locations
                          and exit.
  -l, --long              Use long format: show file sizes, and timestamps
      --uri               Show file/directory URIs
      --readonly-uri      Show readonly file/directory URIs
  -F, --classify          Append '/' to directory names, and '*' to mutable
      --json              Show the raw JSON output
  -d, --node-directory=   Look here to find out which Tahoe node should be used
                          for all operations. The directory should either
                          contain a full Tahoe node, or a file named node.url
                          which points to some other Tahoe node. It should also
                          contain a file named private/aliases which contains
                          the mapping from alias name to root dirnode URI.
                          [default: ~/.tahoe]
  -u, --node-url=         URL of the tahoe node to use, a URL like
                          "http://127.0.0.1:3456". This overrides the URL found
                          in the --node-directory .
      --dir-cap=          Which dirnode URI should be used as the 'tahoe' alias.
      --help              Display this help and exit.

List the contents of some portion of the grid.

error: no alias specified, and the default 'tahoe' alias doesn't exist.
kevan@b8chem-87:~$ 

or, perhaps better still, the CLI code could look in ~/.tahoe/private/aliases and choose one of those instead of requiring the 'tahoe' alias (failing gracefully with something like the message above if nothing is there, of course).

[kevan]

Here is a test that exercises the first case above and fails.

(whether or not we'd want to have a distinct test for having aliases none of which are called tahoe depends on how this is solved)

[kevan]

Other CLI commands process the alias in the same way as ls, though. Let's see how they do it.

(the 'tahoe-test' node has no aliases)

'tahoe backup'

pathos:~ kacarstensen$ tahoe backup -d tahoe-test entab.c software
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/Current/bin/tahoe", line 8, in <module>
    load_entry_point('allmydata-tahoe==1.6.0-r4228', 'console_scripts', 'tahoe')()
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 102, in run
    rc = runner(sys.argv[1:])
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 89, in runner
    rc = cli.dispatch[command](so)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/cli.py", line 473, in backup
    rc = tahoe_backup.backup(options)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/tahoe_backup.py", line 311, in backup
    return bu.run()
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/tahoe_backup.py", line 95, in run
    rootcap, path = get_alias(options.aliases, options.to_dir, DEFAULT_ALIAS)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/common.py", line 150, in get_alias
    return aliases[default], path
KeyError: 'tahoe'

'tahoe check'

pathos:~ kacarstensen$ tahoe check -d tahoe-test 
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/Current/bin/tahoe", line 8, in <module>
    load_entry_point('allmydata-tahoe==1.6.0-r4228', 'console_scripts', 'tahoe')()
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 102, in run
    rc = runner(sys.argv[1:])
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 89, in runner
    rc = cli.dispatch[command](so)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/cli.py", line 493, in check
    rc = tahoe_check.check(options)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/tahoe_check.py", line 18, in check
    rootcap, path = get_alias(options.aliases, where, DEFAULT_ALIAS)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/common.py", line 150, in get_alias
    return aliases[default], path
KeyError: 'tahoe'

'tahoe cp'

pathos:~ kacarstensen$ tahoe cp -d tahoe-test entab.c dest
Success: file copied 

'tahoe get'

pathos:~ kacarstensen$ tahoe get -d tahoe-test file
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/Current/bin/tahoe", line 8, in <module>
    load_entry_point('allmydata-tahoe==1.6.0-r4228', 'console_scripts', 'tahoe')()
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 102, in run
    rc = runner(sys.argv[1:])
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 89, in runner
    rc = cli.dispatch[command](so)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/cli.py", line 434, in get
    rc = tahoe_get.get(options)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/tahoe_get.py", line 16, in get
    rootcap, path = get_alias(aliases, from_file, DEFAULT_ALIAS)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/common.py", line 150, in get_alias
    return aliases[default], path
KeyError: 'tahoe'

'tahoe manifest'

pathos:~ kacarstensen$ tahoe manifest -d tahoe-test
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/Current/bin/tahoe", line 8, in <module>
    load_entry_point('allmydata-tahoe==1.6.0-r4228', 'console_scripts', 'tahoe')()
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 102, in run
    rc = runner(sys.argv[1:])
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 89, in runner
    rc = cli.dispatch[command](so)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/cli.py", line 483, in manifest
    rc = tahoe_manifest.manifest(options)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/tahoe_manifest.py", line 87, in manifest
    return ManifestStreamer().run(options)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/tahoe_manifest.py", line 28, in run
    rootcap, path = get_alias(options.aliases, where, DEFAULT_ALIAS)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/common.py", line 150, in get_alias
    return aliases[default], path
KeyError: 'tahoe'

'tahoe mkdir'

pathos:~ kacarstensen$ tahoe mkdir -d tahoe-test
URI:DIR2:<dircap>

'tahoe mv'

pathos:~ kacarstensen$ tahoe mv -d tahoe-test afile anotherfile
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/Current/bin/tahoe", line 8, in <module>
    load_entry_point('allmydata-tahoe==1.6.0-r4228', 'console_scripts', 'tahoe')()
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 102, in run
    rc = runner(sys.argv[1:])
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 89, in runner
    rc = cli.dispatch[command](so)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/cli.py", line 463, in mv
    rc = tahoe_mv.mv(options, mode="move")
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/tahoe_mv.py", line 20, in mv
    rootcap, from_path = get_alias(aliases, from_file, DEFAULT_ALIAS)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/common.py", line 150, in get_alias
    return aliases[default], path
KeyError: 'tahoe'

'tahoe put'

pathos:~ kacarstensen$ tahoe put -d tahoe-test a.out
200 OK
URI:CHK:<cap>

'tahoe rm'

pathos:~ kacarstensen$ tahoe rm -d tahoe-test afile
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/Current/bin/tahoe", line 8, in <module>
    load_entry_point('allmydata-tahoe==1.6.0-r4228', 'console_scripts', 'tahoe')()
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 102, in run
    rc = runner(sys.argv[1:])
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/runner.py", line 89, in runner
    rc = cli.dispatch[command](so)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/cli.py", line 458, in rm
    rc = tahoe_rm.rm(options)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/tahoe_rm.py", line 18, in rm
    rootcap, path = get_alias(aliases, where, DEFAULT_ALIAS)
  File "/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/allmydata_tahoe-1.6.0_r4228-py2.6.egg/allmydata/scripts/common.py", line 150, in get_alias
    return aliases[default], path
KeyError: 'tahoe'

'tahoe webopen'

pathos:~ kacarstensen$ tahoe webopen -d tahoe-test
pathos:~ kacarstensen$ 

So I guess this isn't specific to 'tahoe ls', but instead is something that relates to many CLI tools. I'm updating the summary accordingly.

[warner]

I like the error: no alias specified, and the default 'tahoe' alias doesn't exist. message. I'd like it even better it we added a second line with instructions: To create one, use "tahoe create-alias tahoe".

And yeah, some CLI commands make as much (or more) sense without an alias.. "tahoe mkdir", "tahoe put", "tahoe get" are frequently used with raw caps, either accepting or returning them. It's the commands that always require aliases that are in most need of this improved error message.

[davidsarah]

#681 was a duplicate for tahoe ls. I've kept this ticket because it is more general and has more information.

[kevan]

I'm attaching a patch that I think fixes this, and a few other problems related to explicitly specified aliases that don't exist.

When you invoke a command with no alias when tahoe: doesn't exist, or with an explicit alias that doesn't exist, you'll see something like:

wlan98-239:tahoe-1.6 kacarstensen$ ./bin/tahoe webopen fake:
error: Unknown alias 'fake', please create it with 'tahoe add-alias' or 'tahoe create-alias'.

or

wlan1-92:tahoe-1.6 kacarstensen$ ./bin/tahoe get -d ~/tahoe-test fake
error: No alias specified, and the default 'tahoe' alias doesn't exist. To create it, use 'tahoe create-alias tahoe'.

[kevan]

fixes for #939

[davidsarah]

I can't see any problems in the code.

In the tests patch:

• on line 30, "C:\Windows" should be "C:\\Windows".
• on line 71, the basedir should be cli/Ln/ln_with_nonexistent_alias, not cli/Ln/ln_without_alias.
• the string passed to failUnlessIn is sometimes "error", sometimes "error:", and sometimes "error: ". Make it consistent.
• the file open calls should use "wb" for the mode.

Also, tahoe webopen with no arguments currently raises TypeError: object of type 'NoneType' has no len() (#855). Either fix this, or add a TODO comment referencing #855 where the relevant test would be.

[davidsarah]

Replying to davidsarah:

Also, tahoe webopen with no arguments currently raises TypeError: object of type 'NoneType' has no len()

Oh, that was because I hadn't specified --node-directory (which is a separate bug).

What is relevant to this ticket is that the tests should include test_webopen_without_alias.

[kevan]

Thanks for the review.

So I'm clear: have you found a way to break tahoe webopen that is (or should be) fixed in this ticket, but isn't tested by my patches? Or is there some other reason that you'd like to see the test there?

[davidsarah]

Unless I'm mistaken, there should only be two backslashes in "C:
Windows", not four.

So I'm clear: have you found a way to break tahoe webopen that is (or should be) fixed in this ticket, but isn't tested by my patches?

No (I thought I had, but I was mistaken). There is currently no test for tahoe webopen without arguments, but I'll leave it up to you whether you want to fix that in this ticket.

[kevan]

Replying to davidsarah:

Unless I'm mistaken, there should only be two backslashes in "C:
Windows", not four.

You're right -- I interpreted your comment as meaning that C:\ in a Windows path has two slashes, and I typed 4 to deal with escaping. But you meant that I literally should replace that string in the code with C:\\Windows. I'll fix that -- thanks.

No (I thought I had, but I was mistaken). There is currently no test for tahoe webopen without arguments, but I'll leave it up to you whether you want to fix that in this ticket.

I think it would be more appropriate to add it when #855 is fixed. It's helpful to have something that is broken when writing a test -- that way, you have something well-defined to test for.

[kevan]

tests for #939 -- review this one

[davidsarah]

Looks good.

[zooko]

fixed by 63c8c6574745374a and c00a62a2e78a9b33. Thanks!