I'm using GitHub API v 4 to learn GraphQL. Here is a broken query to fetch blobs (files) and their text content for a given branch:
query GetTree($branch: String = "master") {
repository(name: "blog-content", owner: "lzrski") {
branch: ref(qualifiedName: "refs/heads/${branch}") {
name
target {
... on Commit {
tree {
entries {
name
object {
... on Blob {
isBinary
text
}
}
}
}
}
}
}
}
}
As you see on line 3 there is my attempt of guessing interpolation syntax, but it does not work - I leave it as an illustration of my intention.
I could provide a fully qualified name for a revision, but that doesn't seem particularly elegant. Is there any GraphQL native way of manipulating strings?
I don't think there's anything in the GraphQL specification that specifically outlines any methods for manipulating string values within a query.
However, when utilizing GraphQL queries within an actual application, you will provide most of the arguments for your query by utilizing variables that are passed alongside your query inside your request. So rather than being done inside your query, most of your string manipulation will be done within your client code when composing the JSON that will represent your variables.
Related
This might seem like an odd question, or something really straightforward, but honestly I am struggling to figure out how to do this. I am working in Node.js and I want to set data I have saved on a node object into my GraphQL mutation.
I'm working with a vendor's GraqhQL API, so this isn't something I have created myself, nor do I have a schema file for it. I'm building a mutation that will insert a record into their application, and I can write out everything manually and use a tool like Postman to manually create a new record...the structure of the mutation is not my problem.
What I'm struggling to figure out is how to build the mutation with variables from my node object without just catting a bunch of strings together.
For example, this is what I'm trying to avoid:
class MyClass {
constructor() {
this.username = "my_username"
this.title = "Some Title"
}
}
const obj = new MyClass()
let query = "mutation {
createEntry( input: {
author: { username: \"" + obj.username + "\" }
title: \"" + obj.title + "\"
})
}"
I've noticed that there are a number of different node packages out there for working with Graphql, but none of their documentation that I've seen really addresses the above situation. I've been completely unsuccessful in my Googling attempts, can someone please point me in the right direction? Is there a package out there that's useful for just building queries without requiring a schema or trying to send them at the same time?
GraphQL services typically implement this spec when using HTTP as a transport. That means you can construct a POST request with four parameters:
query - A Document containing GraphQL Operations and Fragments to execute.
operationName - (Optional): The name of the Operation in the Document to execute.
variables - (Optional): Values for any Variables defined by the Operation.
extensions - (Optional): This entry is reserved for implementors to extend the protocol however they see fit.
You can use a Node-friendly version of fetch like cross-fetch, axios, request or any other library of your choice to make the actual HTTP request.
If you have dynamic values you want to substitute inside the query, you should utilize variables to do so. Variables are defined as part of your operation definition at the top of the document:
const query = `
mutation ($input: SomeInputObjectType!) {
createEntry(input: $input) {
# whatever other fields assuming the createEntry
# returns an object and not a scalar
}
}
`
Note that the type you use will depend on the type specified by the input argument -- replace SomeInputObjectType with the appropriate type name. If the vendor did not provide adequate documentation for their service, you should at least have access to a GraphiQL or GraphQL Playground instance where you can look up the argument's type. Otherwise, you can use any generic GraphQL client like Altair and view the schema that way.
Once you've constructed your query, make the request like this:
const variables = {
input: {
title: obj.title,
...
}
}
const response = await fetch(YOUR_GRAPHQL_ENDPOINT, {
method: 'POST',
headers: { 'Content-Type': 'application/json' },
body: JSON.stringify({ query, variables }),
})
const { data, errors } = await response.json()
I have written a piece of software that parses and formats the fourth parameter of a graphql resolver function (the info object) to be used elsewhere. I would like to write unit tests for this software. Specifically, I do not want to build the GraphQLResolveInfo object myself, because doing that would be very cumbersome, error-prone and hard to maintain. Instead, I want to write human-readable query strings and convert them to GraphQLResolveInfo objects so I can pass those to my software.
After extensive googling and reading of the graphql-js source code, I have not found a simple way to do what they are doing internally. I'm really hoping that I am missing something.
What I am not trying to do is use the graphql-tag library, because that just generates an AST which has a very different format from the GraphQLResolveInfo type.
Has anyone done this before? Help would be much appreciated!
I will keep monitoring this question to see if a better answer comes along, but I've finally managed to solve my particular issue by creating as close an approximation of the GraphQLResolveInfo object as I need for my particular use case.
The GraphQLResolveInfo object is composed of several attributes, two of which are called fieldNodes and fragments. Both are in fact parts of the same AST that graphql-tag generates from a query string. These are the only parts of the GraphQLResolveInfo object that concern the software I wrote, the rest of it is ignored.
So here is what I did:
import gql from 'graphql-tag';
// The converter function
const convertQueryToResolveInfo = (query) => {
const operation = query.definitions
.find(({ kind }) => kind === 'OperationDefinition');
const fragments = query.definitions
.filter(({ kind }) => kind === 'FragmentDefinition')
.reduce((result, current) => ({
...result,
[current.name.value]: current,
}), {});
return {
fieldNodes: operation.selectionSet.selections,
fragments,
};
};
// An example call
const query = gql`
query {
foo {
bar
}
}
`;
const info = convertQueryToResolveInfo(query);
From the AST generated by graphql-tag, I extract and modify the operation and fragment definitions so that they look the way they do within the GraphQLResolveInfo object. This is by no means perfect and may be subject to change in the future depending on how my software evolves, but it is a relatively brief solution for my particular problem.
Does the BotBuilder Node SDK actively strip out anything that is stored the dialogData object?
For example, I have created a simple loop and I am storing a regex in session.dialogData.questions. When I console log this after storing it, I can see that my regex is stored as expected:
{
validation: /^[0-9]{19}$/,
}
However, when I try and log the same session.dialogData.questions object in the next step of my waterfall, then the regex seems to have been converted into an empty object:
{
validation: {}
}
I presume this a deliberate attempt to prevent XSS and other types of exploitation?
The code for this example can be found below:
const builder = require('botbuilder')
const lib = new builder.Library('FormBuilder')
lib.dialog('/', [
(session, args) => {
session.dialogData.questions = {
validation: /^[0-9]{19}$/
}
console.log(session.dialogData.questions)
builder.Prompts.confirm(session, 'Would you like to proceed?')
},
(session, results) => {
console.log(session.dialogData.questions)
}
])
module.exports.createLibrary = () => {
return lib.clone()
}
Regarding your initial question, no the SDK doesn't actively strip anything out of the dialogData object. Anything that is, except for regexp...
I'm not sure why this is, but for the time being I recommend storing your pattern as a string, '^[0-9]{19}$', and then constructing a new regexp via new RegExp(session.dialogData.questions.validation) when needed.
I tried storing a method to construct a new RegExp using this.questions.validation, but likewise this was also stripped out.
Edit:
Per Ezequiel's comment, this isn't a Bot Framework issue in the end. It is not possible to store non-serializable data inside JSON.
Lucene does not permit use of a * or ? symbol as the first character of a search when going through the query parser. Although lucene permits the use of wildcards at the start for other implementations such as lucene.net, this query parser quirk also flows into Cloudant's Lucene-based search.
Lets say we want to emulate: q=foo:*
Can this be specified as: q=foo:([\u0000 TO \uffff] OR [-Infinity TO Infinity])
and the negation as
q=*:* AND NOT foo:([\u0000 TO \uffff] OR [-Infinity TO Infinity])
One solution is to add an index which names the included field names. For example:
function(doc) {
var included = [];
if(doc.foo) {
index("foo", doc.foo);
included.push("foo");
}
if(doc.bar) {
index("bar", doc.bar);
included.push("bar");
}
if(included.length > 0) {
index("has", included.join(" "));
}
}
You could then use
?q=has:foo
to find all docs with a foo field.
The following is confusing me a lot. I have been spending quite a bit of time trying to understand why collection.find() doesn't work with regex passed as an object. The regex match is coming over HTTP wrapped in the body of a POST request. Then I try to gather the query (in string format) and perform the query. The problem seems to be that unless the regex is written inside Node without quotes, it won't work. That is, it must be a literal without quotes.
For example, the following works fine:
var query1 = {
company: {
'$regex': /goog/
}
};
collection.find(query1, {}).toArray(function (err, docs) {
// Got results back. Awesome.
});
However, if the data comes wrapped in an object, it doesn't return anything. I suspect it's because the value gets quoted behind the scenes (i.e. "/goog/"):
// Assume
var query2 = {
company: {
'$regex': query.company
}
};
collection.find(query2, {}).toArray(function (err, docs) {
// Got nothing back.
});
I have tested it with the mongo shell and I can confirm the following:
// Returns 5 results
db.getCollection("contacts").find( { "company": /goog/ } )
// Doesn't match anything
db.getCollection("contacts").find( { "company": "/goog/" } )
Furthermore, I just discovered the following: if I write the value with quotes
// Works fine
var companyRegex = {'$regex': /goog/};
var query3 = {
company: companyRegex
};
So technically, a "literal" regex without quotes wrapped in an object works fine. But if it's a string, it won't work. Even after trying to replace the double-quotes and single-quotes with nothing (i.e. essentially removing them.)
Any idea how can I get the regex match be passed verbatim to find()? I've researched it, finding lots of potential solutions, alas it's not working for me.
Thanks in advance!
Let me focus on one line of your post. This is where the problem might be:
The regex match is coming over HTTP wrapped in the body of a POST request.
This seems problematic because:
The only structures that survive serialization between client/server are:
boolean
number
string
null *
objects and arrays containing these basic types
objects and arrays containing object and arrays [of more obj/array] of these basic types
Regexp, Date, Function, and a host of others require reconstruction, which means
passing a string or pair of strings for the match and option components of the Regexp and running Regexp() on the receiving end to reconstruct.
Regexp gets a bit messy because Regexp.toString() and Regexp() do not appear to be inverses of each others: /someMatch/.toString() is "/someMatch/" but RegExp("/someMatch/") is //someMatch// and what was needed instead to rebuild the regexp was just RegExp("someMatch"), which is /someMatch/. I hope this helps.
JSON.stringify(/someMatch/) is {} (at least on Chrome).
So instead of trying to build a general transport, I recommend re instantiating a particular field as a regexp.
* Irrelevant note: (null is fine but undefined is peculiar. JSON won't stringify undefineds in objects and turns undefined into null in Arrays. I recognize this isn't part of your problem, just trying to be complete in describing what can be serialized.)