Add a development mode for contributions in "flogo ensure"

[debovema]

What kind of change does this PR introduce? (check one with "x")

[] Bugfix
[x] Feature
[] Code style update (formatting, local variables)
[] Refactoring (no functional changes, no api changes)
[] Other... Please describe:

Fixes: N/A

What is the current behavior?
When developing a contribution for Flogo, it is often mandatory to make updates in core repositories of Flogo (such as TIBCOSoftware/flogo-contrib and TIBCOSoftware/flogo-lib repositories). Before a Pull Request can be created, these updates are commited and pushed to a forked repository on a new branch but must be imported in Go as if they were coming from official repositories. It is a tedious work to manage this workflow.

What is the new behavior?
The new behavior is to simplify the development of contributions in Flogo environment.
Especially, it adds following features :

• In flogo ensure command, a -dev switch enables the creation of symbolic links from vendor to pkg for explicit constraints in Gopkg.toml.

For instance, the following constraint:

[[constraint]]
  name = "github.com/TIBCOSoftware/flogo-contrib"
  branch = "some-branch"
  source = "github.com/alternate-account/flogo-contrib"

will remove the $APP_HOME/src/APP_NAME/vendor/github.com/TIBCOSoftware/flogo-contrib directory and replace it by a symbolic link to $APP_HOME/pkg/dep/sources/https---github.com-alternate-account-flogo--contrib.
Whereas the original $APP_HOME/src/APP_NAME/vendor/github.com/TIBCOSoftware/flogo-contrib directory which is just a copy of its counterpart in $APP_HOME/pkg with the right branch/version copied, the link points to a full Git working directory using the right branch/version too.
This is easier to manage updates to be commited and pushed to the fork in a single place.

• In flogo installcommand, new flags are defined:
  • switch -s to specify an alternate source in a [[constraint]] of Gopkg.toml file
  • switch -u to force the update of a [[constraint]] in Gopkg.toml file if it already exists in Gopkg.lock file (currently it is ignored and a message asks to add it manually in the file)
  • switch -o to create an [[override]] instead of a [[constraint]] of Gopkg.toml file

For instance:

flogo install -u -v some-branch -s github.com/alternate-account/flogo-contrib github.com/TIBCOSoftware/flogo-contrib
flogo install -u -v some-branch -s github.com/alternate-account/flogo-lib github.com/TIBCOSoftware/flogo-lib
flogo install -u -o -v master github.com/apache/thrift

will create the following sections:

[[constraint]]
  name = "github.com/TIBCOSoftware/flogo-contrib"
  branch = "some-branch"
  source = "github.com/alternate-account/flogo-contrib"

[[constraint]]
  name = "github.com/TIBCOSoftware/flogo-lib"
  branch = "some-branch"
  source = "github.com/alternate-account/flogo-lib"

[[override]]
  name = "github.com/apache/thrift"
  branch = "master"

Once the alternate configuration is set in Gopkg.toml, a call to flogo ensure -dev will prepare the application for development mode.

How to install to test?

go get -u github.com/TIBCOSoftware/flogo-cli/...

cd $GOPATH/src/github.com/TIBCOSoftware/flogo-cli

git remote add square-it https://github.com/square-it/flogo-cli.git
git pull square-it ensure-development-mode

go get -u ./...

and to switch back to the official Flogo CLI, simply run:

rm -rf $GOPATH/src/github.com/TIBCOSoftware/flogo-cli

go get -u github.com/TIBCOSoftware/flogo-cli/...

[emilienthomas]

OK