Initial commit

.gitignore

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+dist

LICENSE

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+Copyright (c) 2020 Dexter Chua
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

Makefile

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+PLUGIN_ID=srcf.redact
+PLUGIN_VERSION=1.0.0
+
+CWD := $(dir $(abspath $(lastword $(MAKEFILE_LIST))))
+
+export GO111MODULE=on
+
+.PHONY: build
+build:
+	rm -rf dist/
+
+	for os in linux darwin windows; do \
+		export TARGET=$(CWD)/dist/$$os/$(PLUGIN_ID); \
+		mkdir -p $$TARGET; \
+		cd $(CWD)/src && env GOOS=linux GOARCH=amd64 go build -o $$TARGET/plugin-$$os-amd64; cd ..; \
+		cp plugin.json $$TARGET; \
+		tar -C $$TARGET/.. -cvzf $(CWD)/dist/$(PLUGIN_ID)-$(PLUGIN_VERSION)-$$os-amd64.tar.gz $(PLUGIN_ID); \
+	done
+
+.PHONY: clean
+clean:
+	rm -rf dist/

README.md

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+# srcf.redact
+
+This Mattermost plugin lets team administrators delete old messages from their
+channels based on their age. It provides two commands:
+
+ * `/channel_id` returns the channel id
+ * `/delete_posts` this is the command that actually deletes the messages.
+
+The delete command is currently only able to delete messages older than a
+specific number of days. Pull requests to enhance its functionality (e.g. to
+allow messages sent between two dates, or other duration formats) are welcome.

go.mod

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+module github.com/mattermost/mattermost-plugin-demo
+
+go 1.12
+
+require (
+	github.com/mattermost/mattermost-plugin-api v0.0.9
+	github.com/mattermost/mattermost-server/v5 v5.3.2-0.20200313113657-e2883bfe5f37
+	github.com/mholt/archiver/v3 v3.3.0
+	github.com/pkg/errors v0.9.1
+)

plugin.json

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+{
+    "id": "srcf.redact",
+    "name": "Message Redaction Plugin",
+    "description": "This plugin allows team administrators to delete old messages",
+    "version": "1.0.0",
+    "min_server_version": "5.6.0",
+    "server": {
+        "executables": {
+            "linux-amd64": "plugin-linux-amd64",
+            "darwin-amd64": "plugin-darwin-amd64",
+            "windows-amd64": "plugin-windows-amd64"
+        }
+    }
+}

src/main.go

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+package main
+
+import (
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/mattermost/mattermost-server/v5/model"
+	"github.com/mattermost/mattermost-server/v5/plugin"
+)
+
+const PostPerPage = 100
+
+type Plugin struct {
+	plugin.MattermostPlugin
+}
+
+func (p *Plugin) ExecuteCommand(c *plugin.Context, args *model.CommandArgs) (*model.CommandResponse, *model.AppError) {
+	command_args := strings.Fields(args.Command)
+	trigger := strings.TrimPrefix(command_args[0], "/")
+
+	switch trigger {
+	case "channel_id":
+		return &model.CommandResponse{
+			ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+			Text:         "Channel id: " + args.ChannelId,
+		}, nil
+	case "delete_posts":
+		if !p.API.HasPermissionToChannel(args.UserId, args.ChannelId, model.PERMISSION_DELETE_OTHERS_POSTS) {
+			return &model.CommandResponse{
+				ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+				Text:         "Permission denied",
+			}, nil
+		}
+
+		if command_args[1] != args.ChannelId {
+			return &model.CommandResponse{
+				ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+				Text:         "First argument must be channel id. First argument is " + command_args[1],
+			}, nil
+		}
+		n, err := strconv.ParseFloat(command_args[2], 64)
+		if err != nil {
+			return &model.CommandResponse{
+				ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+				Text:         "Second arguments must be a number",
+			}, nil
+		}
+
+		cutoff := time.Now().Unix()*1000 - int64(n*24*60*60*1000)
+
+		deleted := 0
+		// Mattermost returns page in reverse chronological order. We first
+		// find the first page with an old enough post.
+		page := 0
+		for {
+			posts, err := p.API.GetPostsForChannel(args.ChannelId, page+1, PostPerPage)
+			if err != nil {
+				return &model.CommandResponse{
+					ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+					Text:         "Failed to retrieve posts",
+				}, nil
+			}
+			if len(posts.Order) == 0 {
+				break
+			}
+			if posts.Posts[posts.Order[len(posts.Order)-1]].CreateAt < cutoff {
+				break
+			}
+			page += 1
+		}
+
+		// Now page is the first page with a post we have to delete. First
+		// delete all posts in subsequent pages
+		for {
+			posts, err := p.API.GetPostsForChannel(args.ChannelId, page+1, PostPerPage)
+			if err != nil {
+				return &model.CommandResponse{
+					ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+					Text:         "Failed to retrieve posts",
+				}, nil
+			}
+			if len(posts.Order) == 0 {
+				break
+			}
+			for _, pid := range posts.Order {
+				if e := p.API.DeletePost(pid); e != nil {
+					return &model.CommandResponse{
+						ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+						Text:         "Error deleting post " + pid,
+					}, nil
+				}
+				deleted += 1
+			}
+		}
+
+		// Now delete the rest in the final page
+		posts, err := p.API.GetPostsForChannel(args.ChannelId, page, PostPerPage)
+		for i := len(posts.Order) - 1; i >= 0; i-- {
+			pid := posts.Order[i]
+			if posts.Posts[pid].CreateAt < cutoff {
+				if e := p.API.DeletePost(pid); e != nil {
+					return &model.CommandResponse{
+						ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+						Text:         "Error deleting post " + pid,
+					}, nil
+				}
+				deleted += 1
+			} else {
+				break
+			}
+		}
+
+		return &model.CommandResponse{
+			ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+			Text:         strconv.Itoa(deleted) + " posts older than " + command_args[2] + " days deleted",
+		}, nil
+	}
+	return &model.CommandResponse{
+		ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL,
+		Text:         "Unknown command: " + args.Command,
+	}, nil
+}
+
+func (p *Plugin) OnActivate() error {
+	if err := p.API.RegisterCommand(&model.Command{
+		Trigger:          "channel_id",
+		AutoComplete:     true,
+		AutoCompleteDesc: "Displays channel id",
+	}); err != nil {
+		return err
+	}
+	if err := p.API.RegisterCommand(&model.Command{
+		Trigger:          "delete_posts",
+		AutoComplete:     true,
+		AutoCompleteDesc: "Usage: /delete_posts <channel_id> <n>; This command deletes all posts more than n days old in this channel. The first argument is the channel_id obtained from /channel_id.",
+	}); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func main() {
+	plugin.ClientMain(&Plugin{})
+}

src/manifest.go

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+package main
+
+import (
+	"strings"
+
+	"github.com/mattermost/mattermost-server/v5/model"
+)
+
+var manifest *model.Manifest
+
+const manifestStr = `
+{
+  "id": "srcf.redact",
+  "name": "Message Redaction Plugin",
+  "description": "This plugin allows team administrators to delete old messages",
+  "version": "1.0.0",
+  "min_server_version": "5.6.0",
+  "server": {
+    "executables": {
+      "linux-amd64": "plugin-linux-amd64",
+      "darwin-amd64": "plugin-darwin-amd64",
+      "windows-amd64": "plugin-windows-amd64"
+    },
+    "executable": ""
+  }
+}
+`
+
+func init() {
+	manifest = model.ManifestFromJson(strings.NewReader(manifestStr))
+}