Commit 1fd7b60e by Ben Tranter

Add more information to basic diff logic

parent a3d22ae9
......@@ -98,13 +98,7 @@ func (b *BasicDiff) Basic(lines []*JSONLine) []*BasicBlock {
blocks := make([]*BasicBlock, 0)
for _, line := range lines {
// In order to produce distinct "blocks" when rendering the basic diff,
// we need a way to distinguish between differnt sections of data.
// To do this, we consider the value(s) of each top-level JSON key to
// represent a distinct block for Grafana's JSON data structure, so
// we perform this check to see if we've entered a new "block". If we
// have, we simply append the existing block to the array of blocks.
if b.LastIndent == 2 && line.Indent == 1 && line.Change == ChangeNil {
if b.returnToTopLevelKey(line) {
if b.Block != nil {
blocks = append(blocks, b.Block)
}
......@@ -114,56 +108,9 @@ func (b *BasicDiff) Basic(lines []*JSONLine) []*BasicBlock {
// check for a change in depth inside the JSON data structures.
b.LastIndent = line.Indent
// TODO: why special handling for indent 2?
// Here we
// If the line's indentation is at level 1, then we know it's a top
// level key in the JSON document. As mentioned earlier, we treat these
// specially as they indicate their values belong to distinct blocks.
//
// At level 1, we only record single-line changes, ie, the "added",
// "deleted", "old" or "new" cases, since we know those values aren't
// arrays or maps. We only handle these cases at level 2 or deeper,
// since for those we either output a "change" or "summary". This is
// done for formatting reasons only, so we have logical "blocks" to
// display.
if line.Indent == 1 {
switch line.Change {
case ChangeNil:
if line.Change == ChangeNil {
if line.Key != "" {
b.Block = &BasicBlock{
Title: line.Key,
Change: line.Change,
}
}
}
case ChangeAdded, ChangeDeleted:
blocks = append(blocks, &BasicBlock{
Title: line.Key,
Change: line.Change,
New: line.Val,
LineStart: line.LineNum,
})
case ChangeOld:
b.Block = &BasicBlock{
Title: line.Key,
Old: line.Val,
Change: line.Change,
LineStart: line.LineNum,
}
case ChangeNew:
b.Block.New = line.Val
b.Block.LineEnd = line.LineNum
// For every "old" change there is a corresponding "new", which
// is why we wait until we detect the "new" change before
// appending the change.
blocks = append(blocks, b.Block)
default:
// ok
if block, ok := b.handleTopLevelChange(line); ok {
blocks = append(blocks, block)
}
}
......@@ -182,8 +129,8 @@ func (b *BasicDiff) Basic(lines []*JSONLine) []*BasicBlock {
// finding the change, we append it to the current block, and begin
// performing comparisons again.
if line.Indent > 1 {
// Ensure a single line change
if line.Key != "" && line.Val != nil && !b.writing {
// check to ensure a single line change
if b.isSingleLineChange(line) {
switch line.Change {
case ChangeAdded, ChangeDeleted:
......@@ -211,13 +158,31 @@ func (b *BasicDiff) Basic(lines []*JSONLine) []*BasicBlock {
//ok
}
// otherwise, we're dealing with a change at a deeper level. We
// know there's a change somewhere in the JSON tree, but we
// don't know exactly where, so we go deeper.
} else {
// if the change is anything but unchanged, continue processing
//
// we keep "narrowing" the key as we go deeper, in order to
// correctly report the key name for changes found within an
// object or array.
if line.Change != ChangeUnchanged {
if line.Key != "" {
b.narrow = line.Key
b.keysIdent = line.Indent
}
// if the change isn't nil, and we're not already writing
// out a change, then we've found something.
//
// First, try to determine the title of the embedded JSON
// object. If it's an empty string, then we're in an object
// or array, so we default to using the "narrowed" key.
//
// We also start recording the basic summary, until we find
// the next `ChangeUnchanged`.
if line.Change != ChangeNil {
if !b.writing {
b.writing = true
......@@ -237,6 +202,17 @@ func (b *BasicDiff) Basic(lines []*JSONLine) []*BasicBlock {
}
}
}
// if we find a `ChangeUnchanged`, we do one of two things:
//
// - if we're recording a change already, then we know
// we've come to the end of that change block, so we write
// that change out be recording the line number of where
// that change ends, and append it to the current block's
// summary.
//
// - if we're not recording a change, then we do nothing,
// since the BasicDiff doesn't report on unchanged JSON
// values.
} else {
if b.writing {
b.writing = false
......@@ -251,6 +227,81 @@ func (b *BasicDiff) Basic(lines []*JSONLine) []*BasicBlock {
return blocks
}
// returnToTopLevelKey indicates that we've moved from a key at one level deep
// in the JSON document to a top level key.
//
// In order to produce distinct "blocks" when rendering the basic diff,
// we need a way to distinguish between differnt sections of data.
// To do this, we consider the value(s) of each top-level JSON key to
// represent a distinct block for Grafana's JSON data structure, so
// we perform this check to see if we've entered a new "block". If we
// have, we simply append the existing block to the array of blocks.
func (b *BasicDiff) returnToTopLevelKey(line *JSONLine) bool {
return b.LastIndent == 2 && line.Indent == 1 && line.Change == ChangeNil
}
// handleTopLevelChange handles a change on one of the top-level keys on a JSON
// document.
//
// If the line's indentation is at level 1, then we know it's a top
// level key in the JSON document. As mentioned earlier, we treat these
// specially as they indicate their values belong to distinct blocks.
//
// At level 1, we only record single-line changes, ie, the "added",
// "deleted", "old" or "new" cases, since we know those values aren't
// arrays or maps. We only handle these cases at level 2 or deeper,
// since for those we either output a "change" or "summary". This is
// done for formatting reasons only, so we have logical "blocks" to
// display.
func (b *BasicDiff) handleTopLevelChange(line *JSONLine) (*BasicBlock, bool) {
switch line.Change {
case ChangeNil:
if line.Change == ChangeNil {
if line.Key != "" {
b.Block = &BasicBlock{
Title: line.Key,
Change: line.Change,
}
}
}
case ChangeAdded, ChangeDeleted:
return &BasicBlock{
Title: line.Key,
Change: line.Change,
New: line.Val,
LineStart: line.LineNum,
}, true
case ChangeOld:
b.Block = &BasicBlock{
Title: line.Key,
Old: line.Val,
Change: line.Change,
LineStart: line.LineNum,
}
case ChangeNew:
b.Block.New = line.Val
b.Block.LineEnd = line.LineNum
// For every "old" change there is a corresponding "new", which
// is why we wait until we detect the "new" change before
// appending the change.
return b.Block, true
default:
// ok
}
return nil, false
}
// isSingleLineChange ensures we're iterating over a single line change (ie,
// either a single line or a old-new value pair was changed in the JSON file).
func (b *BasicDiff) isSingleLineChange(line *JSONLine) bool {
return line.Key != "" && line.Val != nil && !b.writing
}
// encStateMap is used in the template helper
var (
encStateMap = map[ChangeType]string{
......@@ -273,7 +324,9 @@ var (
)
var (
// tplBlock is the whole thing
// tplBlock is the container for the basic diff. It iterates over each
// basic block, expanding each "change" and "summary" belonging to every
// block.
tplBlock = `{{ define "block" -}}
{{ range . }}
<div class="diff-group">
......@@ -319,7 +372,7 @@ var (
{{ end }}
{{ end }}`
// tplChange is the template for changes
// tplChange is the template for basic changes.
tplChange = `{{ define "change" -}}
<li class="diff-change-group">
<span class="bullet-position-container">
......@@ -346,7 +399,7 @@ var (
</li>
{{ end }}`
// tplSummary is for basis summaries
// tplSummary is for basic summaries.
tplSummary = `{{ define "summary" -}}
<div class="diff-group-name">
<i class="diff-circle diff-circle-{{ getChange .Change }} fa fa-circle-o diff-list-circle"></i>
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment