distribution/docs/building.md

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# Build the development environment
The first prerequisite of properly building distribution targets is to have a Go
development environment setup. Please follow [How to Write Go Code](https://golang.org/doc/code.html)
for proper setup. If done correctly, you should have a GOROOT and GOPATH set in the
environment.
If a Go development environment is setup, one can use `go get` to install the
`registry` command from the current latest:
```sh
go get github.com/docker/distribution/cmd/registry
```
The above will install the source repository into the `GOPATH`.
Now create the directory for the registry data (this might require you to set permissions properly)
```sh
mkdir -p /var/lib/registry
```
... or alternatively `export REGISTRY_STORAGE_FILESYSTEM_ROOTDIRECTORY=/somewhere` if you want to store data into another location.
The `registry`
binary can then be run with the following:
```
$ $GOPATH/bin/registry -version
$GOPATH/bin/registry github.com/docker/distribution v2.0.0-alpha.1+unknown
```
> __NOTE:__ While you do not need to use `go get` to checkout the distribution
> project, for these build instructions to work, the project must be checked
> out in the correct location in the `GOPATH`. This should almost always be
> `$GOPATH/src/github.com/docker/distribution`.
The registry can be run with the default config using the following
incantation:
```
$ $GOPATH/bin/registry $GOPATH/src/github.com/docker/distribution/cmd/registry/config-dev.yml
INFO[0000] endpoint local-5003 disabled, skipping app.id=34bbec38-a91a-494a-9a3f-b72f9010081f version=v2.0.0-alpha.1+unknown
INFO[0000] endpoint local-8083 disabled, skipping app.id=34bbec38-a91a-494a-9a3f-b72f9010081f version=v2.0.0-alpha.1+unknown
INFO[0000] listening on :5000 app.id=34bbec38-a91a-494a-9a3f-b72f9010081f version=v2.0.0-alpha.1+unknown
INFO[0000] debug server listening localhost:5001
```
If it is working, one should see the above log messages.
### Repeatable Builds
For the full development experience, one should `cd` into
`$GOPATH/src/github.com/docker/distribution`. From there, the regular `go`
commands, such as `go test`, should work per package (please see
[Developing](#developing) if they don't work).
A `Makefile` has been provided as a convenience to support repeatable builds.
Please install the following into `GOPATH` for it to work:
```
go get github.com/tools/godep github.com/golang/lint/golint
```
**TODO(stevvooe):** Add a `make setup` command to Makefile to run this. Have to think about how to interact with Godeps properly.
Once these commands are available in the `GOPATH`, run `make` to get a full
build:
```
$ GOPATH=`godep path`:$GOPATH make
+ clean
+ fmt
+ vet
+ lint
+ build
github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar
github.com/Sirupsen/logrus
github.com/docker/libtrust
...
github.com/yvasiyarov/gorelic
github.com/docker/distribution/registry/handlers
github.com/docker/distribution/cmd/registry
+ test
...
ok github.com/docker/distribution/digest 7.875s
ok github.com/docker/distribution/manifest 0.028s
ok github.com/docker/distribution/notifications 17.322s
? github.com/docker/distribution/registry [no test files]
ok github.com/docker/distribution/registry/api/v2 0.101s
? github.com/docker/distribution/registry/auth [no test files]
ok github.com/docker/distribution/registry/auth/silly 0.011s
...
+ /Users/sday/go/src/github.com/docker/distribution/bin/registry
+ /Users/sday/go/src/github.com/docker/distribution/bin/registry-api-descriptor-template
+ /Users/sday/go/src/github.com/docker/distribution/bin/dist
+ binaries
```
The above provides a repeatable build using the contents of the vendored
Godeps directory. This includes formatting, vetting, linting, building,
testing and generating tagged binaries. We can verify this worked by running
the registry binary generated in the "./bin" directory:
```sh
$ ./bin/registry -version
./bin/registry github.com/docker/distribution v2.0.0-alpha.2-80-g16d8b2c.m
```
### Developing
The above approaches are helpful for small experimentation. If more complex
tasks are at hand, it is recommended to employ the full power of `godep`.
The Makefile is designed to have its `GOPATH` defined externally. This allows
one to experiment with various development environment setups. This is
primarily useful when testing upstream bugfixes, by modifying local code. This
can be demonstrated using `godep` to migrate the `GOPATH` to use the specified
dependencies. The `GOPATH` can be migrated to the current package versions
declared in `Godeps` with the following command:
```sh
godep restore
```
> **WARNING:** This command will checkout versions of the code specified in
> Godeps/Godeps.json, modifying the contents of `GOPATH`. If this is
> undesired, it is recommended to create a workspace devoted to work on the
> _Distribution_ project.
With a successful run of the above command, one can now use `make` without
specifying the `GOPATH`:
```sh
$ make
```
If that is successful, standard `go` commands, such as `go test` should work,
per package, without issue.
Storage Driver: Ceph Object Storage (RADOS) This driver implements the storagedriver.StorageDriver interface and uses Ceph Object Storage as storage backend. Since RADOS is an object storage and no hierarchy notion, the following convention is used to keep the filesystem notions stored in this backend: * All the objects data are stored with opaque UUID names prefixed (e.g. "blob:d3d232ff-ab3a-4046-9ab7-930228d4c164). * All the hierarchy information are stored in rados omaps, where the omap object identifier is the virtual directory name, the keys in a specific are the relative filenames and the values the blob object identifier (or empty value for a sub directory). e.g. For the following hierarchy: /directory1 /directory1/object1 /directory1/object2 /directory1/directory2/object3 The omap "/directory1" will contains the following key / values: - "object1" "blob:d3d232ff-ab3a-4046-9ab7-930228d4c164" - "object2" "blob:db2e359d-4af0-4bfb-ba1d-d2fd029866a0" - "directory2" "" The omap "/directory1/directory2" will contains: - "object3" "blob:9ae2371c-81fc-4945-80ac-8bf7f566a5d9" * The MOVE is implemented by changing the reference to a specific blob in its parent virtual directory omap. This driver stripes rados objects to a fixed size (e.g. 4M). The idea is to keep small objects (as done by RBD on the top of RADOS) that will be easily synchronized accross OSDs. The information of the original object (i.e total size of the chunks) is stored as a Xattr in the first chunk object. Signed-off-by: Vincent Giersch <vincent.giersch@ovh.net>
2015-04-23 16:13:52 +00:00
### Optional build tags
Optional [build tags](http://golang.org/pkg/go/build/) can be provided using
the environment variable `DOCKER_BUILDTAGS`.
To enable the [Ceph RADOS storage driver](storage-drivers/rados.md)
(librados-dev and librbd-dev will be required to build the bindings):
```sh
export DOCKER_BUILDTAGS='include_rados'
```