Struct apollo_parser::Parser

pub struct Parser<'a> { /* private fields */ }

Parse GraphQL schemas or queries into a typed AST.

Example

The API to parse a query or a schema is the same, as the parser currently accepts a &str. Here is an example of parsing a query:

use apollo_parser::Parser;

let query = "
{
    animal
    ...snackSelection
    ... on Pet {
      playmates {
        count
      }
    }
}
";
// Create a new instance of a parser given a query above.
let parser = Parser::new(query);
// Parse the query, and return a SyntaxTree.
let ast = parser.parse();
// Check that are no errors. These are not part of the AST.
assert_eq!(0, ast.errors().len());

// Get the document root node
let doc = ast.document();
// ... continue

Here is how you’d parse a schema:

use apollo_parser::Parser;
let core_schema = r#"
schema @core(feature: "https://specs.apollo.dev/join/v0.1") {
  query: Query
  mutation: Mutation
}

enum join__Graph {
  ACCOUNTS @join__graph(name: "accounts")
}
"#;
let parser = Parser::new(core_schema);
let ast = parser.parse();

assert_eq!(0, ast.errors().len());

let document = ast.document();

Implementations

impl<'a> Parser<'a>

pub fn new(input: &'a str) -> Self

Create a new instance of a parser given an input string.

pub fn recursion_limit(self, recursion_limit: usize) -> Self

Configure the recursion limit to use while parsing.

pub fn token_limit(self, token_limit: usize) -> Self

Configure the limit on the number of tokens to parse. If an input document is too big, parsing will be aborted.

By default, there is no limit.

pub fn parse(self) -> SyntaxTree

Parse the current tokens.

Trait Implementations

impl<'a> Debug for Parser<'a>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.