author | Matt Harbison <matt_harbison@yahoo.com> |
Thu, 05 Jan 2023 17:38:14 -0500 | |
branch | stable |
changeset 49883 | e90767a71dc0 |
parent 43632 | 2e017696181f |
permissions | -rw-r--r-- |
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internals: add some brief documentation about censor
Augie Fackler <augie@google.com>
parents:
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1 |
The censor system allows retroactively removing content from |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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2 |
files. Actually censoring a node requires using the censor extension, |
1b699a208cee
internals: add some brief documentation about censor
Augie Fackler <augie@google.com>
parents:
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3 |
but the functionality for handling censored nodes is partially in core. |
1b699a208cee
internals: add some brief documentation about censor
Augie Fackler <augie@google.com>
parents:
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4 |
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Augie Fackler <augie@google.com>
parents:
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5 |
Censored nodes in a filelog have the flag ``REVIDX_ISCENSORED`` set, |
1b699a208cee
internals: add some brief documentation about censor
Augie Fackler <augie@google.com>
parents:
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6 |
and the contents of the censored node are replaced with a censor |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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7 |
tombstone. For historical reasons, the tombstone is packed in the |
1b699a208cee
internals: add some brief documentation about censor
Augie Fackler <augie@google.com>
parents:
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8 |
filelog metadata field ``censored``. This allows censored nodes to be |
1b699a208cee
internals: add some brief documentation about censor
Augie Fackler <augie@google.com>
parents:
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9 |
(mostly) safely transmitted through old formats like changegroup |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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10 |
versions 1 and 2. When using changegroup formats older than 3, the |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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11 |
receiver is required to re-add the ``REVIDX_ISCENSORED`` flag when |
1b699a208cee
internals: add some brief documentation about censor
Augie Fackler <augie@google.com>
parents:
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changeset
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12 |
storing the revision. This depends on the ``censored`` metadata key |
1b699a208cee
internals: add some brief documentation about censor
Augie Fackler <augie@google.com>
parents:
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changeset
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13 |
never being used for anything other than censoring revisions, which is |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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14 |
true as of January 2017. Note that the revlog flag is the |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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15 |
authoritative marker of a censored node: the tombstone should only be |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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consulted when looking for a reason a node was censored or when revlog |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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17 |
flags are unavailable as mentioned above. |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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18 |
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parents:
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19 |
The tombstone data is a free-form string. It's expected that users of |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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20 |
censor will want to record the reason for censoring a node in the |
1b699a208cee
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Augie Fackler <augie@google.com>
parents:
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21 |
tombstone. Censored nodes must be able to fit in the size of the |
1b699a208cee
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parents:
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content being censored. |