diff --git a/packages/backend-common/src/reading/types.ts b/packages/backend-common/src/reading/types.ts index f7fad4dd7a..dd230a754d 100644 --- a/packages/backend-common/src/reading/types.ts +++ b/packages/backend-common/src/reading/types.ts @@ -23,7 +23,17 @@ import { Config } from '@backstage/config'; */ export type UrlReader = { read(url: string): Promise; + + /** + * A replacement for the read method that supports options and complex responses. + * + * Use this whenever it is available, as the read method will be deprecated and + * eventually removed in the future. + */ + readUrl?(url: string, options?: ReadUrlOptions): Promise; + readTree(url: string, options?: ReadTreeOptions): Promise; + search(url: string, options?: SearchOptions): Promise; }; @@ -42,6 +52,40 @@ export type ReaderFactory = (options: { treeResponseFactory: ReadTreeResponseFactory; }) => UrlReaderPredicateTuple[]; +/** + * An options object for readUrl operations. + */ +export type ReadUrlOptions = { + /** + * An etag can be provided to check whether readUrl's response has changed from a previous execution. + * + * In the readUrl() response, an etag is returned along with the data. The etag is a unique identifer + * of the data, usually the commit SHA or etag from the target. + * + * When an etag is given in ReadUrlOptions, readUrl will first compare the etag against the etag + * on the target branch. If they match, readUrl will throw a NotModifiedError indicating that the readUrl + * response will not differ from the previous response which included this particular etag. If they + * do not match, readUrl will return the rest of ReadUrlResponse along with a new etag. + */ + etag?: string; +}; + +/** + * A response object for readUrl operations. + */ +export type ReadUrlResponse = { + /** + * Returns the data that was read from the remote URL. + */ + buffer(): Promise; + + /** + * Etag returned by content provider. + * Can be used to compare and cache responses when doing subsequent calls. + */ + etag?: string; +}; + /** * An options object for readTree operations. */ @@ -66,14 +110,17 @@ export type ReadTreeOptions = { * In the readTree() response, an etag is returned along with the tree blob. The etag is a unique identifer * of the tree blob, usually the commit SHA or etag from the target. * - * When a etag is given in ReadTreeOptions, readTree will first compare the etag against the etag + * When an etag is given in ReadTreeOptions, readTree will first compare the etag against the etag * on the target branch. If they match, readTree will throw a NotModifiedError indicating that the readTree - * response will not differ from the previous response which included this particular etag. If they mismatch, - * readTree will return the rest of ReadTreeResponse along with a new etag. + * response will not differ from the previous response which included this particular etag. If they + * do not match, readTree will return the rest of ReadTreeResponse along with a new etag. */ etag?: string; }; +/** + * A response object for readTree operations. + */ export type ReadTreeResponse = { /** * files() returns an array of all the files inside the tree and corresponding functions to read their content. @@ -87,7 +134,8 @@ export type ReadTreeResponse = { dir(options?: ReadTreeResponseDirOptions): Promise; /** - * A unique identifer of the tree blob, usually the commit SHA or etag from the target. + * Etag returned by content provider. + * Can be used to compare and cache responses when doing subsequent calls. */ etag: string; };