Deprecated: moved into github.com/kitsunium/sdk/internal (ADR 0171), which no consumer imports; update with: go get github.com/kitsunium/sdk/pkg/v1/<family>@latest for each family you import && go mod tidy
Documentation
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Overview ¶
Package jsonpatch computes the structural difference between two JSON documents as RFC 6902 operations — add, remove and replace, each at an RFC 6901 JSON Pointer — with the value each operation writes AND the value it replaces or removes (ADR 0143). Public facade: pkg/v1/data/codec/jsonpatch.
It is what a record's history needs to say what changed between two of its versions: the operations are the edits, both values are what a reader shows, and applied in order to the first document they give the second.
How documents are compared ¶
Each document must be exactly one JSON value, read strictly: no duplicated member name, valid UTF-8, no trailing data. Values are compared as RFC 6902 §4.6 compares them — strings once unescaped, numbers numerically (1, 1.0 and 1e0 are one number, compared exactly, never through a float), arrays element by element, objects by member name whatever their order.
What the operations are ¶
- Two objects: a member only the first has is removed, one only the second has is added, and one both have is compared in turn. Members come in byte order of their names, so the same two documents always give the same operations.
- Two arrays: the elements both keep, in order, are found — the longest common subsequence of the elements that differ, after the equal ones at both ends — and between two kept elements, those removed and those added are paired in order and compared in turn, the rest removed or added. An insertion in the middle is one add, not a rewrite of every element after it. Indices are those of the array as the operations before have left it, as RFC 6902 applies them.
- Anything else that differs — another kind, another string, another number — is replaced whole; two roots of different kinds are one replace at "".
What it is not ¶
It emits no move, copy or test, and does not apply a patch. A value is the JSON of that part of the document, compact; a number keeps its spelling. Nothing it returns in an error comes from a document.
Package jsonpatch — a JSON document read into a tree, compared by value, and written back compact.
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type EditValue ¶
type EditValue struct {
// Op is add, remove or replace.
Op Op `json:"op"`
// Path is the RFC 6901 JSON Pointer of the value the operation changes.
Path string `json:"path"`
// Value is the value the operation writes: add and replace; absent for
// remove.
Value json.RawMessage `json:"value,omitempty"`
// Old is the value the operation replaces or removes: replace and
// remove; absent for add.
Old json.RawMessage `json:"old,omitempty"`
}
EditValue is one operation of a diff: what it does, where, and both values. Its JSON is an RFC 6902 operation, with the value it replaces or removes under "old" — a member RFC 6902 does not define for these operations, which a patch applier ignores (§4) — so a list of them is a JSON Patch document.
type Op ¶
type Op string
Op is what an operation does, as RFC 6902 names it.
const ( // Add adds a member to an object, or inserts an element into an array // before the one at the index — after every element when the index is // the array's length. Add Op = "add" // Remove removes a member of an object, or the element at the index. Remove Op = "remove" // Replace replaces the value at the path, the whole document at "". Replace Op = "replace" )
The three operations a diff emits.
Source Files