To translate an OPDS 2.0 book catalog quickly, localize the discovery text that readers see while preserving publication identifiers, format types, acquisition relations and links. A multilingual title should help someone recognize a book, but it must not make a paid publication appear free, a preview appear complete or an English-language edition appear to contain a Chinese translation. Test catalog browsing and the final borrow, purchase or download action together. Those interactions determine whether the localization is genuinely accurate.
People looking for OPDS 2.0 translation, multilingual ebook catalog metadata, or library acquisition link QA often begin with a catalogue that displays the right books but uses unfamiliar labels. A librarian may want families to browse in Mandarin while borrowing English e-books; a publisher may need separate metadata for translated editions; a reading app may need to explain “preview,” “borrow” and “download” without confusing rights. OPDS 2.0 has a JSON-based model influenced by the Readium Web Publication Manifest and provides specific link relationships for acquisition actions.
This guide uses the OPDS Catalog 2.0 living specification and Readium’s publication metadata model. It shows how to separate a translated catalog listing from a translated book edition, represent multilingual titles, protect acquisition URLs and rights statements, test price and loan language, diagnose typical failures and transfer the method to a new library scenario. The examples are educational fixtures, not functioning e-book transactions or certification of a complete OPDS client.
Clarify whether you are translating discovery or content
Imagine a school library with a list of science reading materials. A parent wants to browse the catalog in Chinese, but the actual books are mostly in English. Translating the title shown on a catalog card may help discovery; it does not produce a translated book. The metadata.language value describes the language of the publication itself where used for that purpose. Changing it to Chinese because the card is translated would mislead readers about the content they will receive.
A separate Chinese edition is a different problem. It may have a distinct identifier, publisher metadata, language, availability and acquisition link. The library should relate editions properly according to its cataloging model rather than replace the original English publication’s language and download URL. A translator must ask which work or edition the record describes. This prevents a catalog’s improved multilingual search from concealing an edition mismatch that only becomes apparent after a family downloads the book.
Define the deliverable in one sentence: “Parents can find the existing English science books using Chinese catalog labels, while the actual content language and access conditions remain accurate.” If the project also includes translating descriptions, navigation categories or app buttons, list those as separate fields. If it includes acquiring rights to Chinese editions, that is a publishing and procurement task, not routine text localization. Keeping these jobs distinct makes progress measurable and ownership clear.
Understand what OPDS 2.0 actually organizes
OPDS 2.0 is designed to distribute information about publications through machine-readable catalogs. A feed can contain navigation links, publication lists, facets and groups. It uses JSON and inherits much of its publication metadata model from Readium. A reader application follows a feed’s collections and link relationships to display books and guide actions. Localizing the text of a navigation item can make browsing easier, but the link’s relationship and destination still determine which collection or transaction opens.
The specification identifies a catalog feed with media type application/opds+json. A feed includes a title in its metadata, a self reference and at least one relevant collection role according to its model. A single feed can contain several collections. Translators should not edit those structural keys merely because they look like ordinary English nouns. The names navigation, publications, groups, links and metadata are part of the format. A reader app expects these keys and may reject or ignore replacements.
Publication entries have their own metadata and links. A book’s author and publisher information, identifier, content language and format need to survive a translated catalog view. An OPDS client may not show every metadata property, and different apps can choose different card layouts. The practical task is to provide correct source values and test the display on the actual clients in use. A well-formed feed that one client handles correctly is not proof that every reading app will show the same multilingual title or acquisition message.
Protect identity when several titles describe one publication
Readium’s default publication metadata context allows alternate representations of titles in different languages or scripts. This is useful when the catalog has legitimate translated display titles for the same publication. The title strings can vary while the publication identity remains the same. A book known to readers by an English title and a translated Chinese description should not become two independent publications solely because the catalog offers two languages. Store a stable identifier and an approved mapping between titles.
Do not confuse translated display title with official title-of-publication authority. A librarian may supply a helpful translated title as a finding aid, while the published edition itself has an English title printed on its cover. The interface can explain that distinction if required. For example, a Chinese catalog card might show an explanatory translation alongside the official English title. A search result should not imply that an officially published Chinese edition exists if the publisher has not released one.
Catalog identity is also important for saved lists. If a reading app associates bookmarks, borrowing history or recommendations with a stable publication identifier, duplicating a record for each language can fragment that state. A parent who switches languages should still see the same borrowed book and its actual access status. Before localizing metadata, capture the identifier, original title, edition details and any links that the service treats as canonical. Those values form an immutable baseline for the translation pass.
Construct a compact, multilingual OPDS fixture
The following example is a reduced OPDS feed with one publication. It uses a language map for the catalog’s presentation title via the inherited Readium metadata model, while explicitly stating that the illustrated publication itself is in English. The download URL and identifier are fictitious. It demonstrates a free direct-access action; it does not represent a real ebook or prove that a particular reader supports every localized title map.
{
"metadata": {
"title": "School Library Science Collection"
},
"links": [
{
"rel": "self",
"href": "https://example.org/opds/science.json",
"type": "application/opds+json"
}
],
"publications": [
{
"metadata": {
"@type": "http://schema.org/Book",
"title": {
"en": "Rain Garden Experiments",
"zh-Hans": "雨水花园实验"
},
"identifier": "urn:uuid:4b6f8d7e-1b2c-43d4-8e5f-67890abc1234",
"language": "en"
},
"links": [
{
"rel": "download",
"href": "https://example.org/books/rain-garden.epub",
"type": "application/epub+zip"
}
]
}
]
}Review the example as data first. The identifier and href are not translated. The language value stays en because the fictional content is English. The two title strings describe the same listed item, and the download relation indicates a freely accessible download in OPDS 2.0’s simplified acquisition vocabulary. A UI that displays the Chinese title but then claims “Chinese-language ebook” has invented a fact not present in the record. This distinction should appear in acceptance tests.
A JSON parser can check punctuation and object structure. A more specialized OPDS validator should inspect the catalog and acquisition requirements, while a human reviewer checks whether readers understand what they will get. A client may use only one title or prefer a different locale mapping strategy. Therefore the sample is a starting point for testing an actual application’s behavior, not a universal recipe that every reader automatically interprets the same way. Technical validation and reader comprehension both matter.
Distinguish navigation links from acquisition links
A navigation link sends the reader to another catalog collection or page. An acquisition link offers a way to obtain, borrow, buy, preview or subscribe to a publication. These are different classes of interaction. Translating the navigation title “Science experiments” into Chinese is usually a straightforward text task. Translating the text of a borrow button is more consequential because it represents a transaction with time limits or access conditions. Preserve the link relation and destination while reviewing the message that explains it.
If a catalog’s navigation says “New arrivals,” verify that the linked collection actually contains newly added materials according to the library’s definition. Some systems use “new” to mean recently published; others mean newly acquired. A translation that chooses the wrong concept can mislead readers even when the URL works perfectly. Examine the catalog’s sorting or curation policy and write text that matches it. Do not change the relation or link to force it to fit a preferred translation without consulting the catalog owner.
A common implementation error is to localize the JSON key rel or a relation value such as borrow. That breaks machine interpretation. Localize the button or card label supplied by the UI or approved link title field, not the standardized relationship token. The reading app uses relations to decide what action to offer. A visually correct “Borrow” label attached to a buy relation is a serious defect: a user may be sent to a purchase flow they did not expect. Both the copy and underlying action require review.
Translate acquisition language without changing the transaction
OPDS 2.0 distinguishes relations including download, preview, borrow, buy, subscribe and a general acquisition fallback. These distinctions communicate what a user can do. A preview link is for a sample or subset, not the complete publication. A borrow link can represent a time-limited lending transaction. A buy link indicates purchase. A freely accessible download relation should not silently require authentication or payment. The translation should reflect the actual relation and the service’s real behavior.
Loan terminology often varies by library culture. A target-language equivalent of “borrow” should not imply permanent ownership. If a publication requires an active library membership and expires after a stated period, the translated explanation should mention these conditions where the interface exposes them. The link relation does not by itself provide a complete contractual statement; the application may need additional account, loan and rights information. Test from the perspective of an eligible borrower and a visitor without credentials.
Subscriptions and purchases need even greater care. A price expressed in a currency must not change merely because the surrounding text is localized. Converting currency for display is a separate, dynamic commerce function requiring accurate rates and rounding policies. The OPDS metadata may state a numeric price and a currency code. Translate the words explaining the transaction, preserve the underlying values and ensure users see the actual amount before payment. A localized purchase button that misrepresents charges is not a minor text defect.
Handle prices, currency and indirect acquisition correctly
An OPDS acquisition link may carry a price object with fields such as currency and value. These are factual data, not copy for translators. A phrase like “Buy for four dollars” can be localized, but the application must derive the numerical amount and currency from the actual offer. A reviewer should test decimals, currency symbols and screen-reader pronunciation. Do not convert a USD price into a local monetary amount unless the commerce system intentionally provides a verified conversion and clearly distinguishes estimated display from charged currency.
Indirect acquisition can mean that a user follows a link to an intermediate HTML page or license transaction before obtaining an EPUB or another format. The indirectAcquisition metadata helps describe what may eventually be available. A translator should not label the first link “Download EPUB now” if it opens a purchase or authentication page. Use wording such as “View purchase options” or “Borrow through the library” when that accurately reflects the workflow. Then follow the link to verify the actual intermediate step.
There is also a distinction between a file’s media type and the words describing it. application/epub+zip, application/pdf and text/html identify formats for software. They must remain intact. A translated catalog can explain what an EPUB is or which reader software may be needed, but it should not turn one media type into another or hide digital rights management requirements. In QA, capture the declared type, returned content type and resulting user experience. Where they disagree, involve the system owner rather than rewriting a text label to mask the problem.
Check whether the publication language matches user expectations
A reader who searches in Chinese may be comfortable reading English books, but should not be forced to guess. The publication’s content language should remain accurate, even when the catalog’s navigation and summaries are multilingual. A target-language display can say “English-language ebook” or show a language badge based on actual metadata. Do not set metadata.language to the catalog interface’s language automatically. That would conflate the language used for discovery with the language used throughout the book.
Mixed-language books create a more nuanced case. A bilingual children’s book may contain both English and Chinese text, while the catalog offers a translated title in Malay as a finding aid. The catalog team needs a policy for representing publication languages accurately and consistently. A label like “Chinese edition” should be reserved for an edition where the text actually matches that claim. If the underlying metadata cannot express the nuance needed by the local UI, augment the presentation with reviewed explanatory text rather than silently altering an identity field.
Test the first page or an authorized sample where possible. Metadata can be stale or erroneous, and a librarian may discover a mismatch only after opening the file. A translator should flag such issues, but not personally invent new publisher claims. Keep evidence linking the catalog record to the file’s own title page, identifier or published language statement. A correct metadata repair may require cataloging authority or the publisher’s records. This is why linguistic confidence and bibliographic confidence are separate forms of quality.
Preserve author, translator, publisher and edition roles
A book record may identify an author, translator, editor, publisher, series or collection. The OPDS 2.0 model allows additional links for contributors and related metadata. Those relationships tell readers who created the work and which version they are accessing. Translating a person’s name by guesswork can obscure identity, and replacing a translator credit with the author’s name would misrepresent creative contribution. Follow official names, authoritative bibliographic records and local cataloging policy for display forms.
The word “translator” itself can also be confusing in a multilingual catalog. A translated catalog title is not the same as a book translated by a credited literary translator. A school reading guide might explain a title in Chinese for discoverability while the actual book remains the English original. Do not add a translator credit to the publication record simply because a catalog editor translated a summary. The role belongs to the edition’s production history. Catalog localization provenance should be tracked separately in the editorial system.
Series numbering and edition statements need careful handling. A publisher may issue a revised textbook, a workbook supplement and a translated edition with similar covers. If the translated catalog collapses their titles into one generic phrase, students may borrow the wrong volume. Preserve identifiers, sequence position and edition year, then review the target title with the book cover and catalog data. A successful search should distinguish resources that are genuinely different even when they share a topic or author.
Search, facets and grouping create additional language jobs
A multilingual catalog has to work beyond the detail page. Navigation groups such as science, language and mathematics may have translated titles. Search results may combine user queries with indexed metadata. A correct Chinese title that never enters the search index is less useful than its file suggests. Test a small suite of actual user queries and verify that the right book appears with enough distinguishing information. Do not invent search popularity data from a handful of manual tests; record only what the configured system returns.
Facets may represent subject, availability, age range, language or format. The underlying category should remain stable even when its visible label changes. A facet labeled “Free ebooks” should not include purchase-only offers unless the catalog owner deliberately defines a broader category and explains it. Similarly, a book’s subject category is not the same as a level of reading difficulty. A translated category that conflates them can frustrate teachers trying to choose suitable materials for different learners.
Groups also affect orientation. A catalog might contain a “New for Primary 4” group with links to selected works. Translators should confirm what “new” and “Primary 4” mean in this context. The group title is human text, but its collection membership is a curated fact. A fluent title should not imply that every title was endorsed for a particular examination if the library only grouped them for browsing convenience. The content team owns curation and selection; translation communicates it without expanding the claim.
Test language maps and client fallback deliberately
Readium’s publication metadata model supports alternate title representations through language maps. That makes multilingual catalog presentation possible without duplicating the publication identifier. But client selection depends on implementation. A reading application might prefer a target language based on device settings, use a default value, or show a title from another source. The translation team should not assume that adding a zh-Hans key guarantees display in every OPDS reader. Record the exact clients and versions used for acceptance tests.
Fallback is especially important for partial catalogs. A new language rollout may cover navigation and popular book descriptions before every older record receives an approved translation. A client can display the original title when a localized form is absent, provided the presentation does not imply that the original text is already translated. Mark translation coverage in the editorial system. Avoid adding fabricated target values just to reach a numerical coverage target; a reliable fallback is better than a confident but incorrect title.
Check sorting and indexing when local scripts differ. A catalog may sort translated titles according to locale while a saved list uses a stable publication identifier. Switching language should not cause duplicate or missing loans. Test a list containing a book with both English and Chinese titles, one with only English, and one with a mixed-script official title. Observe whether the client preserves identity, shows a predictable fallback and returns to the correct detail page after a selection. These practical checks reveal more than a parser report.
Diagnose a misleading “free download” label
Suppose the Chinese UI displays a large button meaning “Download free ebook,” but tapping it opens a login screen and a borrowing flow. Inspect the OPDS acquisition relation first. If it is borrow, the label is wrong and should explain borrowing or sign-in rather than immediate free download. If the record says download yet the server requires authentication, the metadata or service behavior is inconsistent with the relation’s defined meaning. The translator cannot safely solve both cases with the same sentence.
After locating the mismatch, determine ownership. A translation error belongs to the language/UI team; an incorrect relation belongs to the catalog publisher; a broken or redirected acquisition endpoint belongs to the service operator. Record the user impact and expected transaction. Do not replace borrow with download merely to agree with the current label, because that would misrepresent the acquisition. Correct the relation only through an approved catalog-data change backed by actual service behavior, then retest in every language.
The regression suite should include a signed-in and signed-out user, a preview-only publication, a borrowed title with an expiry, and a purchase offer where the displayed amount is known. Compare the labels, relations, URLs and resulting screens. Test a screen reader’s announcement of the action. A translated catalog passes only when people understand the transaction before they commit to it. A pretty button that creates an unexpected charge or failed loan is a high-severity defect regardless of spelling quality.
Handle availability and loan states honestly
Availability can change independently of translation. A title may be borrowable today and unavailable tomorrow because all copies are loaned. Do not encode “Available now” as an evergreen translation of a static book title. Use a dynamic status drawn from the service where appropriate and translate its possible states separately. A user should understand whether they can borrow, place a hold or wait. Hard-coded availability text can become stale even while the feed’s publication record is otherwise current.
Loan duration is another source of false expectations. A localized note might say “Keep for two weeks,” but the actual loan policy could differ by publication, user group or jurisdiction. Separate policy data from wording so the displayed duration reflects the applicable transaction. If a service supplies an expiration timestamp, preserve that fact and render a locally readable date without altering the underlying time. A language team should not silently round a precise deadline into a more generous promise.
Privacy belongs in these workflows too. A reader app may show a personal bookshelf linked to an authenticated account. Translation resources and sample QA records should not include real borrower credentials, reading histories or license tokens. Use synthetic accounts and books. When translating an account prompt, explain what information is requested without encouraging users to paste secrets into unrelated pages. A safe multilingual catalog makes acquisition clearer while preserving the service’s authentication and confidentiality boundaries.
A structured method for catalog translation teams
Begin with a frozen export of the relevant OPDS feeds and a map of publication identifiers, content languages, acquisition links, link relations, media types and prices. Identify the intended display languages and the exact OPDS client versions. Extract the catalog titles, navigation labels, publication display titles, approved descriptions and UI-owned action messages into a field-specific translation queue. Do not expose machine relations or URLs as editable prose. This separation reduces the chance that a vendor changes functional metadata accidentally.
For each text, store the source, target, locale, context, reviewer and evidence of what a reader will encounter. A book title may need the cover or publisher record for context; a “Borrow” button requires the transaction relation and access conditions. A description of a science workbook may need a subject teacher to confirm that it accurately represents content. Link a translated string to its record and source revision so a future catalog update can flag stale translations. Generic reuse across unrelated books should not be trusted solely because the English words happen to match.
Run technical validation and reader tests as separate gates. A parser checks JSON; an OPDS-aware check reviews feed structure and required link details; a link checker inspects reachable destinations; a bilingual reviewer checks meaning; a reader exercise confirms the action. Try a book that is free, one available by loan, one offering only a sample, and one in an unexpected content language. Document client-specific behavior. No one test can prove everything, but together they provide a practical release argument.
Changed-context exercise with answer
A public library introduces a Malay catalog interface for its educational e-books. Its current English feed lists a free English-language workbook, a bilingual Mandarin–English story that can be borrowed for fourteen days, and a Malay-language novel offered only as a preview before purchase. A junior editor suggests translating all titles, changing metadata.language to ms, and changing every acquisition label to “Get book.” Explain the risks and design a corrected release plan with specific tests.
The correct answer keeps each publication’s true content language and stable identifier. It supplies reviewed Malay display titles where the adopted metadata model and client support them, while retaining the original titles as needed for bibliographic clarity. The free workbook should show a direct-download action only if its download link is genuinely unrestricted. The bilingual story should expose borrowing and the applicable loan terms. The novel’s preview must not be presented as the full purchasable book, and the purchase workflow must be distinguished from the sample.
Test all three titles in Malay and English, with signed-in and signed-out accounts. Verify title selection, content-language indication, relation, href, media type, and final interaction. Check the borrowed story’s loan expiration and the novel’s charge before purchase. If the user selects “Get book” and lands in an unexpected payment flow, the design has failed even though the phrase is generic. This exercise transfers the method from a school library to public lending while preserving the central distinction between finding a book and receiving rights to it.
Practical review checklist
Before release, confirm that every catalog and publication record still has the intended identity, each acquisition link has the correct relationship and target, content language remains truthful, translated titles do not invent new editions, prices retain their currencies and amounts, and available previews are clearly marked as partial. Check the catalog’s navigation, facets, search results, sorting and book detail pages. Test at least one supported OPDS client with language preferences and fallback conditions that match the target audience.
Assign explicit owners. The librarian or bibliographic editor verifies editions, contributors, identifiers and subject categories. The rights or service owner verifies borrow, buy, preview, download and subscription behavior. The translator checks terminology and user expectations. The developer checks JSON, link relations, authentication and rendering. When one person fills several roles, the evidence still needs to cover them separately. This is the fastest reliable way to resolve defects without repeatedly asking the wrong team to change a sentence that was already correct.
Hold release for misrepresented transactions, wrong book language, altered identifiers, unauthorized link changes or translated claims that contradict the file. Lesser wording preferences can be tracked for improvement if they do not mislead readers. Keep a snapshot of the source feed, the accepted target values and the test results. Schedule review when publishers change editions, loan policies or links. A catalog is a live discovery system, so translation QA must be tied to ongoing metadata maintenance rather than treated as a one-time export.
Distinguish editorial titles from verified bibliographic metadata
Readers may search a translated title that is not printed on any edition of the book. A catalog interface can provide a helpful localized discovery label without pretending that a publisher has released a new translation. Record the canonical bibliographic title, any approved alternative-language display title, the publication’s actual content languages, edition identifiers and the source of each statement. In a library, this distinction affects acquisitions, citations and teacher reading lists. If a teacher copies a translated catalog title into a class worksheet and pupils cannot find that title on the cover or inside the book, explain the relationship clearly in the record instead of manufacturing a separate publication. Include the original title in a predictable place when it helps identification. A linguistic review should ask whether the alternate title aids search while keeping the identity and availability of the underlying work truthful.
An OPDS catalog may be consumed by different reading apps with different support for alternate names, sorting and language preferences. Do not treat a technically valid multilingual field as evidence that every client will index it or that readers can filter by it. Run a small compatibility table using a known catalog fixture and at least one client your audience actually uses. Search by the original title and by a translated alternative, open the publication detail page, and note which metadata appears. Repeat with the reader’s locale changed, and include the fallback when no matching title exists. If a client displays only the default, decide whether the service’s own discovery website should carry additional multilingual assistance. Avoid modifying acquisition links or official identifiers merely to force a preferred title into a client that does not support it.
Include rights and availability in every translation handoff
The riskiest book-catalog error is often not a mistranslated noun; it is a promise that changes a transaction. “Read sample,” “Borrow for fourteen days,” “Download free” and “Buy now” establish materially different expectations. A language reviewer needs the actual link relation, access policy and transaction evidence to choose safe text. Where an authentication step appears, state that the account requirement is part of the workflow rather than treating the link as instantly accessible. Where a loan expires, preserve the stated loan duration and distinguish that restriction from ownership of the downloaded file. Where a price is shown, retain the exact currency code and amount unless an authorized commerce system computes a displayed conversion. If terms change after translation approval, send affected labels back to review; a perfectly translated old promise can become misleading when licensing changes.
There is also an accessibility dimension to acquisition QA. A screen reader may announce only the clickable link label, without a surrounding description. A bare “Get” is too ambiguous when one record offers a preview and another a purchase. Test meaningful action names in context, including multiple links for the same book. Confirm that the target destination, link relation and accessible label agree. Users should not need to click a paid link to discover that the interface omitted an important price or limitation. This practice transfers beyond ebooks to library databases, course materials and digital archives: wherever translated discovery leads into access rights, check the real action rather than trusting the attractiveness of the label alone.
Limits and summary
OPDS 2.0 is a living standard whose core has been stable for years, but implementations and practices continue to evolve. It does not guarantee that every reader displays every localized metadata form the same way. Readium metadata capabilities help represent alternate titles, but a real application’s fallback, sorting and link handling still require verification. JSON syntax alone is insufficient evidence of an accessible or correct borrowing experience. Record the tested client and standard version whenever making a compatibility claim.
A catalog translation also has a smaller scope than a book translation. Users may discover an English-language work through Chinese or Malay labels and still need the original language to read it. That is legitimate if explained accurately. A book’s content language, edition, format and license are not changed by the language of the catalog interface. If the project intends to translate the book or create a separate edition, the rights, production and bibliographic workflow must be commissioned and reviewed separately.
The lasting principle is to translate discovery while protecting acquisition truth. Titles and navigation labels can be multilingual; identities, relations, destination links and prices remain grounded in the actual publication and transaction. When teams test what a reader finds and what happens after tapping the button, OPDS catalogs become more accessible without introducing confusion about borrowing, buying or downloading. Speed comes from clear boundaries and repeatable checks, not from translating every string in a JSON document.
Frequently asked questions
1. Does a translated catalog title mean the ebook is translated?
No. The catalog’s display language and the publication’s actual content language are different facts. Preserve accurate language metadata and identify translated editions separately.
2. What is the difference between OPDS 2.0 and Atom-based OPDS 1.x?
OPDS 2.0 uses a JSON-based model built on Readium publication metadata and supports richer collections and link objects. OPDS 1.x is Atom-based; do not apply XML editing assumptions to a JSON feed.
3. Can a publication title use a language map?
The inherited Readium metadata context supports alternate title forms using language tags. Test the actual OPDS reader because not every client necessarily selects or displays them identically.
4. May I translate `rel: "borrow"` into another language?
No. It is a machine-readable relationship value. Translate the interface label while preserving the relation and verifying the associated transaction.
5. When is `download` appropriate?
In OPDS 2.0’s simplified vocabulary it indicates unrestricted free access. If the endpoint demands payment or authentication, review the metadata and service behavior rather than using a misleading label.
6. Is a `preview` the full book?
No. It identifies a subset or sample. The translated button and description should make that limitation clear, particularly when the full book requires purchase or borrowing.
7. Can the catalog convert displayed prices into local currency?
That requires an independent commerce and exchange-rate policy. Translators must not change the original price value or currency code by guesswork; the actual charged amount must be clear.
8. What if a browser or reader ignores the Chinese title?
Check client support for alternate titles, locale selection and fallback. The JSON may be well formed while the specific app still displays the default title. Document that limitation and choose a supported presentation strategy.
9. Who should fix a broken acquisition link?
The catalog or service owner, through an authorized technical change. A language reviewer can identify the defect, but should not substitute an unrelated link or alter the relation to make a label appear correct.
10. What should a minimal multilingual OPDS regression suite include?
Test at least one direct free download, loan, preview, purchase or subscription as applicable, a missing translation fallback, distinct editions, content-language badges, and a real link activation on the target reading app.
Authoritative sources
- OPDS Catalog 2.0 — official living specification
- Readium Web Publication Manifest
- Readium Default Context and multilingual title representations
- OPDS Link Relations Registry
- OPDS 2.0 borrowing best-practice draft