The usefulness of JSON is that while both systems still need to agree on a custom protocol, it gives you an implementation for half of that custom protocol - ubiquitous libraries to parse and generate the format, so the application needs only to handle the semantics of a particular field.

If you want to see what an activity stream looks like, and your browser renders JSON nicely, just grab a random outbox and have a look.)

Of course, CSV is less flexible than JSON. It's suitable when you have a list of items with mostly the same properties, and no nested structures.

At 100,000 entries, this list would be 2.4 MB (that's ~63% less than the JSON)

CSV is a format that's more lightweight than JSON and super well suited to streaming.

Those methods will wait until the entire response has been downloaded, and then parse it. That's because JSON is not a streaming format

JSON is ubiquitous, more lightweight than XML but still flexible enough to represent any data structure you typically need

To summarize the three options we’ve seen, as well as a streaming ijson-based solution:

Spring Boot 处理 Long 类型的 json 数据，前端调用精度丢失，变成 00

ObjectMapper @JsonProperty 不生效问题处理（kotlin）

JSON is a similar, perhaps even more popular, format (and almost[!] a subset of YAML 1.2).

Jackson 通过自定义注解来控制 json key 的格式

为什么说JSON不适合做配置文件？

The @id keyword allows you to give a node a URI. This URI identifies the node. See Node Identifiers in the JSON-LD spec. (The equivalent in Microdata is the itemid attribute, and the equivalent in RDFa Lite is the resource attribute.)

pointer: type: string description: A string containing a JSON pointer to the specific field within a received JSON body that caused the problem, e.g. '/data/attributes/title' to refer to the `title` property within the `attributes` object that is a child of the top level `data` object. example: /data/attributes/title

A workaround you can use is to move additionalProperties to the extending schema and redeclare the properties from the extended schema.

Because additionalProperties only recognizes properties declared in the same subschema, it considers anything other than “street_address”, “city”, and “state” to be additional. Combining the schemas with allOf doesn’t change that.

It’s important to note that additionalProperties only recognizes properties declared in the same subschema as itself. So, additionalProperties can restrict you from “extending” a schema using Schema Composition keywords such as allOf. In the following example, we can see how the additionalProperties can cause attempts to extend the address schema example to fail.

In your scenario, which many, many people encounter, you expect that properties defined in schema1 will be known to schema2; but this is not the case and will never be.

When you do: "allOf": [ { "schema1": "here" }, { "schema2": "here" } ] schema1 and schema2 have no knowledge of one another; they are evaluated in their own context.

I'm not sure if there's a reason why additionalProperties only looks at the sibling-level when checking allowed properties but IMHO this should be changed.

It's unfortunate that additionalProperties only takes the immediate, sibling-level properties into account

additionalProperties applies to all properties that are not accounted-for by properties or patternProperties in the immediate schema.

additionalProperties here applies to all properties, because there is no sibling-level properties entry - the one inside allOf does not count.

You have stumbled upon the most common problem in JSON Schema, that is, its fundamental inability to do inheritance as users expect; but at the same time it is one of its core features.

unevaluatedProperties is like additionalProperties, except that it can "see through" $ref and "see inside" allOf, anyOf, oneOf, if, then, else

I think the answer lies here: Cant see into oneOf or allOf etc. This, I think, is the distinguishing difference between additionalProperties and unevaluatedProperties.

However, unevaluatedProperties has dynamic behavior, meaning that the set of properties to which it applies cannot be determined from static analysis of the schema (either the immediate schema object or any subschemas of that object).

unevaluatedProperties is similar to additionalProperties in that it has a single subschema, and it applies that subschema to instance properties that are not a member of some set.

Also, some Specification constraints cannot be represented with the JSON Schema so it's highly recommended to employ other methods to ensure compliance.

What I want is to use "additionalProperties: false" to validate a union of schemas, but it seems it isn't possible. I already tried with sevaral different combination, but I didn't make it works.

additionalProperties: false works on it, but not along with allOf, because only validate one schema or another.

allOf takes an array of object definitions that are validated independently but together compose a single object.

The latest (draft 2020-12) version of JSON Schema supports the unevaluatedProperties vocabulary (see here). This is quite a useful feature, and facilitates stricter validation while composing properties from multiple sub-schemas (using e.g. allOf) than would otherwise possible.

OAS 3.1 uses all of JSON Schema draft 2020-12 including unevaluatedProperties. You won't find direct references to unevealuatedProperties in the OAS spec because it links to the JSON Schema spec instead of duplicating it's contents.

This object is a superset of the JSON Schema Specification Draft 2020-12.

JSON Schema allows for additionalProperties both a boolean or an object value. true is interpreted as "additional properties follow no restrictions", false means "no additional restrictions", and an object is interpreted as a JSON schema applied to the property values (the empty object is thus equivalent to true).

The vendor prefix (vnd.) indicates that it is custom for this vendor.

The +json indicates that it can be parsed as JSON, but the media type should define further semantics on top of JSON.

05:03 Linking Zotero to Obsidian

When you see a job post mentioning REST or a company discussing REST Guidelines they will rarely mention either hypertext or hypermedia: they will instead mention JSON, GraphQL(!) and the like.

The creator of GraphQL admits this. During his presentation on the library at a Facebook internal conference, an audience member asked him about the difference between GraphQL and SOAP. His response: SOAP requires XML. GraphQL defaults to JSON—though you can use XML.

Conclusion There are decades of history and a broad cast of characters behind the web requests you know and love—as well as the ones that you might have never heard of. Information first traveled across the internet in 1969, followed by a lot of research in the ’70s, then private networks in the ’80s, then public networks in the ’90s. We got CORBA in 1991, followed by SOAP in 1999, followed by REST around 2003. GraphQL reimagined SOAP, but with JSON, around 2015. This all sounds like a history class fact sheet, but it’s valuable context for building our own web apps.

The GS1 Web Vocabulary collects terms defined in various GS1 standards and data systems and made available for general use following Linked Data principles. It is designed as an extension to schema.org and, where relevant, mappings and relationships arising from that vocabulary are made explicit. The initial focus of the GS1 Web Vocabulary is consumer-facing properties for clothing, shoes, food beverage/tobacco and properties common to all products.

In the previous version, using the standard library, once the data is loaded we no longer to keep the file open. With this API the file has to stay open because the JSON parser is reading from the file on demand, as we iterate over the records.

One common solution is streaming parsing, aka lazy parsing, iterative parsing, or chunked processing.