This is based on some code from (closed) PR #7872, but reworked based on
suggestions by @abadger and the other core team members.
Closes#7872 by @darkk (hash_merge/hash_replace filters)
Closes#11153 by @telbizov (merged_dicts lookup plugin)
Now we issue a "Reading … from stdin" prompt if our input isatty(), as
gpg does. We also suppress the "x successful" confirmation message at
the end if we're part of a pipeline.
(The latter requires that we not close sys.stdout in VaultEditor, and
for symmetry we do the same for sys.stdin, though it doesn't matter in
that case.)
This allows the following invocations:
# Interactive use, like gpg
ansible-vault encrypt --output x
# Non-interactive, for scripting
echo plaintext|ansible-vault encrypt --output x
# Separate input and output files
ansible-vault encrypt input.yml --output output.yml
# Existing usage (in-place encryption) unchanged
ansible-vault encrypt inout.yml
…and the analogous cases for ansible-vault decrypt as well.
In all cases, the input and output files can be '-' to read from stdin
or write to stdout. This permits sensitive data to be encrypted and
decrypted without ever hitting disk.
Now that VaultLib always decides to use AES256 to encrypt, we don't need
this broken code any more. We need to be able to decrypt this format for
a while longer, but encryption support can be safely dropped.
Now we don't have to recreate VaultEditor objects for each file, and so
on. It also paves the way towards specifying separate input and output
files later.
It's unused and unnecessary; VaultLib can decide for itself what cipher
to use when encrypting. There's no need (and no provision) for the user
to override the cipher via options, so there's no need for code to see
if that has been done either.
The --new-vault-password-file option works the same as
--vault-password-file but applies only to rekeying (when
--vault-password-file sets the old password). Also update the manpage
to document these options more fully.
`if method in dir(self):` is very inefficient:
- it must construct a list object listing all the object attributes & methods
- it must then perform a O(N) linear scan of that list
Replace it with the idiomatic `if hasattr(self, method):`, which is a
O(1) expected time hash lookup.
Should fix#11981.
