PLT-3383: image proxy support (#7991)

* image proxy support

* go vet fix, remove mistakenly added coverage file

* fix test compile error

* add validation to config settings and documentation to model functions

* add message_source field to post

1 files changed, 71 insertions, 0 deletions

diff --git a/utils/markdown/paragraph.go b/utils/markdown/paragraph.go
new file mode 100644
index 000000000..6a40fdf89
--- /dev/null
+++ b/utils/markdown/paragraph.go
@@ -0,0 +1,71 @@
+// Copyright (c) 2017-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package markdown
+
+import (
+	"strings"
+)
+
+type Paragraph struct {
+	blockBase
+	markdown string
+
+	Text                 []Range
+	ReferenceDefinitions []*ReferenceDefinition
+}
+
+func (b *Paragraph) ParseInlines(referenceDefinitions []*ReferenceDefinition) []Inline {
+	return ParseInlines(b.markdown, b.Text, referenceDefinitions)
+}
+
+func (b *Paragraph) Continuation(indentation int, r Range) *continuation {
+	s := b.markdown[r.Position:r.End]
+	if strings.TrimSpace(s) == "" {
+		return nil
+	}
+	return &continuation{
+		Indentation: indentation,
+		Remaining:   r,
+	}
+}
+
+func (b *Paragraph) Close() {
+	for {
+		for i := 0; i < len(b.Text); i++ {
+			b.Text[i] = trimLeftSpace(b.markdown, b.Text[i])
+			if b.Text[i].Position < b.Text[i].End {
+				break
+			}
+		}
+
+		if len(b.Text) == 0 || b.Text[0].Position < b.Text[0].End && b.markdown[b.Text[0].Position] != '[' {
+			break
+		}
+
+		definition, remaining := parseReferenceDefinition(b.markdown, b.Text)
+		if definition == nil {
+			break
+		}
+		b.ReferenceDefinitions = append(b.ReferenceDefinitions, definition)
+		b.Text = remaining
+	}
+
+	for i := len(b.Text) - 1; i >= 0; i-- {
+		b.Text[i] = trimRightSpace(b.markdown, b.Text[i])
+		if b.Text[i].Position < b.Text[i].End {
+			break
+		}
+	}
+}
+
+func newParagraph(markdown string, r Range) *Paragraph {
+	s := markdown[r.Position:r.End]
+	if strings.TrimSpace(s) == "" {
+		return nil
+	}
+	return &Paragraph{
+		markdown: markdown,
+		Text:     []Range{r},
+	}
+}