feat(gateway): JSON and CBOR response formats (IPIP-328) #9335
There are no files selected for viewing
Binary file not shown.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,237 @@ | ||
| package corehttp | ||
|
|
||
| import ( | ||
| "bytes" | ||
| "context" | ||
| "fmt" | ||
| "html" | ||
| "io" | ||
| "net/http" | ||
| "strings" | ||
| "time" | ||
|
|
||
| ipldlegacy "github.com/ipfs/go-ipld-legacy" | ||
| ipath "github.com/ipfs/interface-go-ipfs-core/path" | ||
| "github.com/ipfs/kubo/tracing" | ||
| "github.com/ipld/go-ipld-prime" | ||
| "github.com/ipld/go-ipld-prime/multicodec" | ||
| mc "github.com/multiformats/go-multicodec" | ||
| "go.opentelemetry.io/otel/attribute" | ||
| "go.opentelemetry.io/otel/trace" | ||
| ) | ||
|
|
||
| // codecToContentType maps the supported IPLD codecs to the HTTP Content | ||
| // Type they should have. | ||
| var codecToContentType = map[uint64]string{ | ||
| uint64(mc.Json): "application/json", | ||
| uint64(mc.Cbor): "application/cbor", | ||
| uint64(mc.DagJson): "application/vnd.ipld.dag-json", | ||
| uint64(mc.DagCbor): "application/vnd.ipld.dag-cbor", | ||
| } | ||
|
|
||
| // contentTypeToCodecs maps the HTTP Content Type to the respective | ||
| // possible codecs. If the original data is in one of those codecs, | ||
| // we stream the raw bytes. Otherwise, we encode in the last codec | ||
| // of the list. | ||
| var contentTypeToCodecs = map[string][]uint64{ | ||
| "application/json": {uint64(mc.Json), uint64(mc.DagJson)}, | ||
| "application/vnd.ipld.dag-json": {uint64(mc.DagJson)}, | ||
| "application/cbor": {uint64(mc.Cbor), uint64(mc.DagCbor)}, | ||
| "application/vnd.ipld.dag-cbor": {uint64(mc.DagCbor)}, | ||
| } | ||
|
|
||
| // contentTypeToExtension maps the HTTP Content Type to the respective file | ||
| // extension, used in Content-Disposition header when downloading the file. | ||
| var contentTypeToExtension = map[string]string{ | ||
| "application/json": ".json", | ||
| "application/vnd.ipld.dag-json": ".json", | ||
| "application/cbor": ".cbor", | ||
| "application/vnd.ipld.dag-cbor": ".cbor", | ||
| } | ||
|
|
||
| func (i *gatewayHandler) serveCodec(ctx context.Context, w http.ResponseWriter, r *http.Request, resolvedPath ipath.Resolved, contentPath ipath.Path, begin time.Time, requestedContentType string) { | ||
| ctx, span := tracing.Span(ctx, "Gateway", "ServeCodec", trace.WithAttributes(attribute.String("path", resolvedPath.String()), attribute.String("requestedContentType", requestedContentType))) | ||
| defer span.End() | ||
|
|
||
| // If the resolved path still has some remainder, return bad request. | ||
| if resolvedPath.Remainder() != "" { | ||
| path := strings.TrimSuffix(resolvedPath.String(), resolvedPath.Remainder()) | ||
| err := fmt.Errorf("%q of %q could not be returned: reading IPLD Kinds other than Links (CBOR Tag 42) is not implemented: try reading %q instead", resolvedPath.Remainder(), resolvedPath.String(), path) | ||
| webError(w, "unsupported pathing", err, http.StatusNotImplemented) | ||
| return | ||
| } | ||
|
|
||
| // No content type is specified by the user (via Accept, or format=). However, | ||
| // we support this format. Let's handle it. | ||
| if requestedContentType == "" { | ||
| cidCodec := resolvedPath.Cid().Prefix().Codec | ||
| isDAG := cidCodec == uint64(mc.DagJson) || cidCodec == uint64(mc.DagCbor) | ||
| acceptsHTML := strings.Contains(r.Header.Get("Accept"), "text/html") | ||
|
|
||
| if isDAG && acceptsHTML { | ||
| i.serveCodecHTML(ctx, w, r, resolvedPath, contentPath) | ||
| } else { | ||
| cidContentType, ok := codecToContentType[cidCodec] | ||
| if !ok { | ||
| // Should not happen unless function is called with wrong parameters. | ||
| err := fmt.Errorf("content type not found for codec: %v", cidCodec) | ||
| webError(w, "internal error", err, http.StatusInternalServerError) | ||
| return | ||
| } | ||
|
|
||
| i.serveCodecRaw(ctx, w, r, resolvedPath, contentPath, cidContentType) | ||
| } | ||
|
|
||
| return | ||
| } | ||
|
|
||
| // Otherwise, the user has requested a specific content type. Let's first get | ||
| // the codecs that can be used with this content type. | ||
| codecs, ok := contentTypeToCodecs[requestedContentType] | ||
| if !ok { | ||
| // This is never supposed to happen unless function is called with wrong parameters. | ||
| err := fmt.Errorf("unsupported content type: %s", requestedContentType) | ||
| webError(w, err.Error(), err, http.StatusInternalServerError) | ||
| return | ||
| } | ||
|
|
||
| // If the requested content type has "dag-", ALWAYS go through the encoding | ||
| // process in order to validate the content. | ||
| if strings.Contains(requestedContentType, "dag-") { | ||
| i.serveCodecConverted(ctx, w, r, resolvedPath, contentPath, requestedContentType, codecs[len(codecs)-1]) | ||
| return | ||
| } | ||
|
|
||
| // Otherwise, check if the data is encoded with the requested content type. | ||
| // If so, we can directly stream the raw data. serveRawBlock cannot be directly | ||
| // used here as it sets different headers. | ||
| for _, codec := range codecs { | ||
| if resolvedPath.Cid().Prefix().Codec == codec { | ||
| i.serveCodecRaw(ctx, w, r, resolvedPath, contentPath, requestedContentType) | ||
| return | ||
| } | ||
| } | ||
|
|
||
| // Finally, if nothing of the above is true, we have to actually convert the codec. | ||
| i.serveCodecConverted(ctx, w, r, resolvedPath, contentPath, requestedContentType, codecs[len(codecs)-1]) | ||
| } | ||
|
|
||
| func (i *gatewayHandler) serveCodecHTML(ctx context.Context, w http.ResponseWriter, r *http.Request, resolvedPath ipath.Resolved, contentPath ipath.Path) { | ||
| codecName := mc.Code(resolvedPath.Cid().Prefix().Codec).String() | ||
| body := fmt.Sprintf(`<!DOCTYPE html> | ||
|
||
| <html lang="en"> | ||
| <head> | ||
| <meta charset="utf-8" /> | ||
| </head> | ||
| <body> | ||
| <p>Requested CID <code>%q</code> uses <code>%q</code> codec.</p> | ||
| <ul> | ||
| <li><a href="?format=json" rel="nofollow">Preview as JSON</a> (<code>application/json</code>)</li> | ||
| <li>Download as | ||
| <ul> | ||
| <li><a href="?format=raw" rel="nofollow">Raw Block</a> (no conversion)</li> | ||
| <li><a href="?format=dag-json" rel="nofollow">DAG-JSON</a> (specs at <a href="https://ipld.io/specs/codecs/dag-json/spec/" rel="noreferrer nofollow">IPLD</a> and <a href="https://www.iana.org/assignments/media-types/application/vnd.ipld.dag-json" rel="noreferrer nofollow">IANA</a>)</li> | ||
| <li><a href="?format=dag-cbor" rel="nofollow">DAG-CBOR</a> (specs at <a href="https://ipld.io/specs/codecs/dag-cbor/spec/" rel="noreferrer nofollow">IPLD</a> and <a href="https://www.iana.org/assignments/media-types/application/vnd.ipld.dag-cbor" rel="noreferrer nofollow">IANA</a>)</li> | ||
| </ul> | ||
| </li> | ||
| </ul> | ||
| </body> | ||
| </html> | ||
| `, resolvedPath.Cid(), codecName) | ||
|
|
||
| _, _ = w.Write([]byte(body)) | ||
| } | ||
|
|
||
| func (i *gatewayHandler) serveCodecRaw(ctx context.Context, w http.ResponseWriter, r *http.Request, resolvedPath ipath.Resolved, contentPath ipath.Path, contentType string) { | ||
| modtime := addCacheControlHeaders(w, r, contentPath, resolvedPath.Cid()) | ||
| name := setCodecContentDisposition(w, r, resolvedPath, contentType) | ||
| w.Header().Set("Content-Type", contentType) | ||
| w.Header().Set("X-Content-Type-Options", "nosniff") | ||
|
|
||
| blockCid := resolvedPath.Cid() | ||
| blockReader, err := i.api.Block().Get(ctx, resolvedPath) | ||
| if err != nil { | ||
| webError(w, "ipfs block get "+blockCid.String(), err, http.StatusInternalServerError) | ||
| return | ||
| } | ||
| block, err := io.ReadAll(blockReader) | ||
| if err != nil { | ||
| webError(w, "ipfs block get "+blockCid.String(), err, http.StatusInternalServerError) | ||
| return | ||
| } | ||
| content := bytes.NewReader(block) | ||
|
|
||
| // ServeContent will take care of | ||
| // If-None-Match+Etag, Content-Length and range requests | ||
| _, _, _ = ServeContent(w, r, name, modtime, content) | ||
| } | ||
|
|
||
| func (i *gatewayHandler) serveCodecConverted(ctx context.Context, w http.ResponseWriter, r *http.Request, resolvedPath ipath.Resolved, contentPath ipath.Path, contentType string, codec uint64) { | ||
| obj, err := i.api.Dag().Get(ctx, resolvedPath.Cid()) | ||
| if err != nil { | ||
| webError(w, "ipfs dag get "+html.EscapeString(resolvedPath.String()), err, http.StatusInternalServerError) | ||
| return | ||
| } | ||
|
|
||
| universal, ok := obj.(ipldlegacy.UniversalNode) | ||
| if !ok { | ||
| err = fmt.Errorf("%T is not a valid IPLD node", obj) | ||
| webError(w, err.Error(), err, http.StatusInternalServerError) | ||
| return | ||
| } | ||
| finalNode := universal.(ipld.Node) | ||
|
|
||
| encoder, err := multicodec.LookupEncoder(codec) | ||
| if err != nil { | ||
| webError(w, err.Error(), err, http.StatusInternalServerError) | ||
| return | ||
| } | ||
|
|
||
| // Keep it in memory so we can detect encoding errors in order to conform | ||
| // to the specification. | ||
| var buf bytes.Buffer | ||
| err = encoder(finalNode, &buf) | ||
| if err != nil { | ||
| webError(w, err.Error(), err, http.StatusInternalServerError) | ||
| return | ||
| } | ||
|
|
||
| // Set Cache-Control and read optional Last-Modified time | ||
| modtime := addCacheControlHeaders(w, r, contentPath, resolvedPath.Cid()) | ||
| setCodecContentDisposition(w, r, resolvedPath, contentType) | ||
| w.Header().Set("Content-Type", contentType) | ||
| w.Header().Set("X-Content-Type-Options", "nosniff") | ||
|
|
||
| // Sets correct Last-Modified header. This code is borrowed from the standard | ||
| // library (net/http/server.go) as we cannot use serveFile. | ||
| if !(modtime.IsZero() || modtime.Equal(unixEpochTime)) { | ||
| w.Header().Set("Last-Modified", modtime.UTC().Format(http.TimeFormat)) | ||
| } | ||
|
|
||
| _, _ = w.Write(buf.Bytes()) | ||
| } | ||
|
|
||
| func setCodecContentDisposition(w http.ResponseWriter, r *http.Request, resolvedPath ipath.Resolved, contentType string) string { | ||
| var dispType, name string | ||
|
|
||
| ext, ok := contentTypeToExtension[contentType] | ||
| if !ok { | ||
| // Should never happen. | ||
| ext = ".bin" | ||
| } | ||
|
|
||
| if urlFilename := r.URL.Query().Get("filename"); urlFilename != "" { | ||
| name = urlFilename | ||
| } else { | ||
| name = resolvedPath.Cid().String() + ext | ||
| } | ||
|
|
||
| switch ext { | ||
| case ".json": // codecs that serialize to JSON can be rendered by browsers | ||
| dispType = "inline" | ||
| default: // everything else is assumed binary / opaque bytes | ||
| dispType = "attachment" | ||
| } | ||
| setContentDispositionHeader(w, name, dispType) | ||
| return name | ||
| } | ||
Oops, something went wrong.
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Uh oh!
There was an error while loading. Please reload this page.