b6e46c9eb8
A simple version control system for dashboards. Closes #1504. Goals 1. To create a new dashboard version every time a dashboard is saved. 2. To allow users to view all versions of a given dashboard. 3. To allow users to rollback to a previous version of a dashboard. 4. To allow users to compare two versions of a dashboard. Usage Navigate to a dashboard, and click the settings cog. From there, click the "Changelog" button to be brought to the Changelog view. In this view, a table containing each version of a dashboard can be seen. Each entry in the table represents a dashboard version. A selectable checkbox, the version number, date created, name of the user who created that version, and commit message is shown in the table, along with a button that allows a user to restore to a previous version of that dashboard. If a user wants to restore to a previous version of their dashboard, they can do so by clicking the previously mentioned button. If a user wants to compare two different versions of a dashboard, they can do so by clicking the checkbox of two different dashboard versions, then clicking the "Compare versions" button located below the dashboard. From there, the user is brought to a view showing a summary of the dashboard differences. Each summarized change contains a link that can be clicked to take the user a JSON diff highlighting the changes line by line. Overview of Changes Backend Changes - A `dashboard_version` table was created to store each dashboard version, along with a dashboard version model and structs to represent the queries and commands necessary for the dashboard version API methods. - API endpoints were created to support working with dashboard versions. - Methods were added to create, update, read, and destroy dashboard versions in the database. - Logic was added to compute the diff between two versions, and display it to the user. - The dashboard migration logic was updated to save a "Version 1" of each existing dashboard in the database. Frontend Changes - New views - Methods to pull JSON and HTML from endpoints New API Endpoints Each endpoint requires the authorization header to be sent in the format, ``` Authorization: Bearer <jwt> ``` where `<jwt>` is a JSON web token obtained from the Grafana admin panel. `GET "/api/dashboards/db/:dashboardId/versions?orderBy=<string>&limit=<int>&start=<int>"` Get all dashboard versions for the given dashboard ID. Accepts three URL parameters: - `orderBy` String to order the results by. Possible values are `version`, `created`, `created_by`, `message`. Default is `versions`. Ordering is always in descending order. - `limit` Maximum number of results to return - `start` Position in results to start from `GET "/api/dashboards/db/:dashboardId/versions/:id"` Get an individual dashboard version by ID, for the given dashboard ID. `POST "/api/dashboards/db/:dashboardId/restore"` Restore to the given dashboard version. Post body is of content-type `application/json`, and must contain. ```json { "dashboardId": <int>, "version": <int> } ``` `GET "/api/dashboards/db/:dashboardId/compare/:versionA...:versionB"` Compare two dashboard versions by ID for the given dashboard ID, returning a JSON delta formatted representation of the diff. The URL format follows what GitHub does. For example, visiting [/api/dashboards/db/18/compare/22...33](http://ec2-54-80-139-44.compute-1.amazonaws.com:3000/api/dashboards/db/18/compare/22...33) will return the diff between versions 22 and 33 for the dashboard ID 18. Dependencies Added - The Go package [gojsondiff](https://github.com/yudai/gojsondiff) was added and vendored.
Go Longest Common Subsequence (LCS)
A package to calculate LCS of slices.
Usage
go get github.com/yudai/golcs
import " github.com/yudai/golcs"
left = []interface{}{1, 2, 5, 3, 1, 1, 5, 8, 3}
right = []interface{}{1, 2, 3, 3, 4, 4, 5, 1, 6}
lcs := golcs.New(left, right)
lcs.Values() // LCS values => []interface{}{1, 2, 5, 1}
lcs.IndexPairs() // Matched indices => [{Left: 0, Right: 0}, {Left: 1, Right: 1}, {Left: 2, Right: 6}, {Left: 4, Right: 7}]
lcs.Length() // Matched length => 4
lcs.Table() // Memo table
All the methods of Lcs cache their return values. For example, the memo table is calculated only once and reused when Values(), Length() and other methods are called.
FAQ
How can I give []byte values to Lcs() as its arguments?
As []interface{} is incompatible with []othertype like []byte, you need to create a []interface{} slice and copy the values in your []byte slice into it. Unfortunately, Go doesn't provide any mesure to cast a slice into []interface{} with zero cost. Your copy costs O(n).
leftBytes := []byte("TGAGTA")
left = make([]interface{}, len(leftBytes))
for i, v := range leftBytes {
left[i] = v
}
rightBytes := []byte("GATA")
right = make([]interface{}, len(rightBytes))
for i, v := range rightBytes {
right[i] = v
}
lcs.New(left, right)
LICENSE
The MIT license (See LICENSE for detail)