Instead of returning histories from `radicle-cob`, we return an
evaluated object which we build during initial graph traversal.
We do this so that branches can be correctly pruned when operations are
invalid at the application level. This way, new operations are not
building on top of invalid ones contained in the history.
To achieve this, we introduce a new `Evaluate` trait that is implemented
by all COBs, and we make change graph evaluation fallible.
Doing this means that we get `apply` errors returned for free when an
invalid transaction is applied, and no longer need to check for action
validity in multiple places.
We also implement a new `Dag::prune` method to avoid having to copy
graph nodes during traversal.
Instead of having two types, we simply have one, called `Entry`, which
we rename from `Change`.
There was no real benefit to having two almost identical types, but lots
of added complexity. This patch simplifies the crate by removing one of
the types.
This change allows for files (blobs) to be embedded into COB entries.
This allows for things like image attachments in issue comments for example.
For now, we only enable this in the `issue` COB.
The way it works is that relevant COB actions carry metadata about which
files are attached to them; and we store those files as blobs inside the
COB entry's *tree* object, under an `embeds/` folder.
The `Embed<T>` type is used for the above, and either carries actual
content, or carries a content-id. Retrieving the actual content is as
simple as asking the repository for a blob with that content-id.
As a possible future extension, MIME types could be stored alongside the
files in a "metadata" file. This could help clients display the content
appropriately.
> I'm going to be making a set of breaking changes to COBs in order to
stabilize the data formats. This is hopefully a one-time change that
bundles various breaking changes.
All COBs have been reworked: issue, patch, id.
The changes included are:
* Revise the assign and tag actions to take a single list of
assignees/tags to set, instead of an "add" and a "remove" list. This
makes API usage simpler when editing issues, and simplifies the apply
function
* Rename "tags" to "labels", and the tag action to label. This is
because tag is confusing in the context of git, as it could mean a git
tag. Using label removes that confusion.
* Use DIDs instead of PublicKeys for assignees -- this is more
future-proof
* Modify the manifest file format in the COB tree. Mainly, remove the
`history_type` key which is redundant, and use camelCase for keys
* Flatten the `Thread` actions into the parent action type
* Ensure that operations on redacted objects do not fail, since
redactions could have happened concurrently
* Use a consistent naming scheme for actions, using `.` as separator
* Consolidate comment types and remove `CodeComment`, by adding an
optional `location` field to `Comment`
* Add many placeholder actions that are not yet implemented
To preserve backwards compatibility, a `legacy` module is created with
the old `apply` function. When loading the manifest, we check whether it
is a legacy COB or a "stable" COB, and in the legacy case, use the
legacy code to materialize the state and then convert the object into
the stable type. Eventually, we'll delete the legacy code.
The additional flexibility in choosing a backend for the COB store will
allow things like "draft" COBs that are stored in a different location,
without changing much of the logic.
Simplify graph traversal and evaluation by building in some of the
functionality into `radicle-dag`, namely the pruning fold.
We avoid building vectors of graph nodes this way, and simply iterate
over the graph in one go.
This allows change commits to have more than one parent that isn't
part of the DAG.
We can use this to create dependencies towards git objects such as
commits, in the case of patch actions.
By introducing a small limitation: only allowing entries in the change
graph to be addressable, instead of individual operations; we
drastically simplify the CRDT implementation.
There are four advantages:
1. Op ids are just regular SHA-1s
2. There's no need for relative IDs, ops never refer to other ops within the
same commit
3. There's no need for a nonce, since commits can't collide, and neither can op IDs
4. `OpId` can just be an alias of `EntryId`
The disadvantage of course, is that we have to be mindful of how we
create op transactions, since each transaction creates an addressable
unit. For example, we must not include multiple patch revisions in the
same transaction.
Before this change, the identity document would be loaded for the
COB signer. This meant that a fork would be needed for that signer.
After this change, it's no longer necessary, since the identity doc
head is computed from available remotes.
While making those changes, it was also apparent that some of the
identity-related functions had bad names and error types, this
was fixed as well.
* Move storage impl into `storage::cob`
* Rename `change::Create` to `change::Template`
* Rename `change::Storage::create` to `change::Storage::store`
Some of the renames are to further distinguish COBs from Changes, and
the different types of "create" operations within cobs.
Signed-off-by: Alexis Sellier <alexis@radicle.xyz>
The latter is a fork of the former, which adds const generics
and a bunch of other quality of life improvements that aren't
in the original crate due to it being unmaintained.
Signed-off-by: Alexis Sellier <alexis@radicle.xyz>
Add quickcheck tests for parse_refstr to ensure the correct
behaviour.
This required adding Arbitrary instances for TypeName and ObjectId, as
well as adding a mechanism for generating Invalid ObjectIds.
Signed-off-by: Fintan Halpenny <fintan.halpenny@gmail.com>
X-Clacks-Overhead: GNU Terry Pratchett
The `Store` trait had a paramter for a `Resource`. This is too
restrictive for implementations, particularly `heartwood`.
Instead, where a unique identifier is needed for the
`object::Storage`, i.e. in `create` and `update`, the identifier
becomes a parameter.
This allows the removal of passing the resource in `list`, `get` and
`changegraph`.
Signed-off-by: Fintan Halpenny <fintan.halpenny@gmail.com>
X-Clacks-Overhead: GNU Terry Pratchett
This is a minimal port of the collaborative objects code from
radicle-link[0].
A `CollaborativeObject` is made up of a `History` of `Change`s that
are expected to be stored in a `git` backend.
The library exposes a CRU series of functions `create`, `get`, `list`,
and `update`.
This implementation differs, to previous one, in that it does not
assume any kind of identity system -- its only assumption is that
identities have an identifier and can be addressed in the `git`
database. This means that it does not require an `author` to be passed
in and it only uses the `resource` (previously `authorizing_identity`)
to store its content-address in the `Change`.
It also foregoes any caching to simplify the port and not make any
early optimisation assumptions.
[0]: https://github.com/radicle-dev/radicle-link/tree/master/cob
Signed-off-by: Fintan Halpenny <fintan.halpenny@gmail.com>
cloudhead
Alexis Sellier
Alexis Sellier
Fintan Halpenny
