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Use variables in Azure Functions out binding

I'm using Azure functions with javascript, and i would like to modify the out binding of path in my functions. For example this is my function.json:
{
"bindings": [
{
"authLevel": "function",
"type": "httpTrigger",
"direction": "in",
"name": "req",
"methods": [
"get",
"post"
]
},
{
"type": "http",
"direction": "out",
"name": "res"
},
{
"name": "outputBlob",
"path": "container/{variableCreatedInFunction}-{rand-guid}",
"connection": "storagename_STORAGE",
"direction": "out",
"type": "blob"
}
]
I Would like to set {variableCreatedInFunction} in index.js, for example:
module.exports = async function (context, req) {
const data = req.body
const date = new Date().toISOString().slice(0, 10)
const variableCreatedInFunction = `dir/path/${date}`
if (data) {
var responseMessage = `Good`
var statusCode = 200
context.bindings.outputBlob = data
} else {
var responseMessage = `Bad`
var statusCode = 500
}
context.res = {
status: statusCode,
body: responseMessage
};
}
Couldn't find any way to this, is it possible?

Bindings are resolved before the function executes. You can use {DateTime} as a binding expression. It will by default be yyyy-MM-ddTHH-mm-ssZ. You can use {DateTime:yyyy} as well (and other formatting patterns, as needed).
Imperative bindings (which is what you want to achieve) is only available in C# and other .NET languages, the docs says:
Binding at runtime In C# and other .NET languages, you can use an
imperative binding pattern, as opposed to the declarative bindings in
function.json and attributes. Imperative binding is useful when
binding parameters need to be computed at runtime rather than design
time. To learn more, see the C# developer reference or the C# script developer reference.
MS might've added it to JS as well by now, since I'm pretty sure I read that exact section more than a year ago, but I can't find anything related to it. Maybe you can do some digging yourself.
If your request content is JSON, the alternative is to include the path in the request, e.g.:
{
"mypath":"a-path",
"data":"yourdata"
}
You'd then be able to do declarative binding like this:
{
"name": "outputBlob",
"path": "container/{mypath}-{rand-guid}",
"connection": "storagename_STORAGE",
"direction": "out",
"type": "blob"
}
In case you need the name/path to your Blob, you'd probably have to chain two functions together, where one acts as the entry point and path generator, while the other is handling the Blob (and of course the binding).
It would go something like this:
Declare 1st function with HttpTrigger and Queue (output).
Have the 1st function create your "random" path containing {date}-{guid}.
Insert a message into the Queue output with the content {"mypath":"2020-10-15-3f3ecf20-1177-4da9-8802-c7ad9ada9a33", "data":"some-data"} (replacing the date and guid with your own generated values, of course...)
Declare 2nd function with QueueTrigger and your Blob-needs, still binding the Blob path as before, but without {rand-guid}, just {mypath}.
The mypath is now used both for the blob output (declarative) and you have the information available from the queue message.

It is not possiable to set dynamic variable in .js and let the binding know.
The value need to be given in advance, but this way may achieve your requirement:
index.js
module.exports = async function (context, req) {
context.bindings.outputBlob = "This is a test.";
context.done();
context.res = {
body: 'Success.'
};
}
function.json
{
"bindings": [
{
"authLevel": "anonymous",
"type": "httpTrigger",
"direction": "in",
"name": "req",
"methods": [
"get",
"post"
]
},
{
"type": "http",
"direction": "out",
"name": "res"
},
{
"name": "outputBlob",
"path": "test/{test}",
"connection": "str",
"direction": "out",
"type": "blob"
}
]
}
local.settings.json
{
"IsEncrypted": false,
"Values": {
"AzureWebJobsStorage": "",
"FUNCTIONS_WORKER_RUNTIME": "node",
"str":"DefaultEndpointsProtocol=https;AccountName=0730bowmanwindow;AccountKey=xxxxxx;EndpointSuffix=core.windows.net"
}
}
Or you can just put the output logic in the body of function. Just use the javascript sdk.

How do I query an index properly with Dynamoose

I'm using Dynamoose to simplify my interactions with DynamoDB in a node.js application. I'm trying to write a query using Dynamoose's Model.query function that will search a table using an index, but it seems like Dynamoose is not including all of the info required to process the query and I'm not sure what I'm doing wrong.
Here's what the schema looks like:
const UserSchema = new dynamoose.Schema({
"user_id": {
"hashKey": true,
"type": String
},
"email": {
"type": String,
"index": {
"global": true,
"name": "email-index"
}
},
"first_name": {
"type": String,
"index": {
"global": true,
"name": "first_name-index"
}
},
"last_name": {
"type": String,
"index": {
"global": true,
"name": "last_name-index"
}
}
)
module.exports = dynamoose.model(config.usersTable, UserSchema)
I'd like to be able to search for users by their email address, so I'm writing a query that looks like this:
Users.query("email").contains(query.email)
.using("email-index")
.all()
.exec()
.then( results => {
res.status(200).json(results)
}).catch( err => {
res.status(500).send("Error searching for users: " + err)
})
I have a global secondary index defined for the email field:
When I try to execute this query, I'm getting the following error:
Error searching for users: ValidationException: Either the KeyConditions or KeyConditionExpression parameter must be specified in the request.
Using the Dynamoose debugging output, I can see that the query winds up looking like this:
aws:dynamodb:query:request - {
"FilterExpression": "contains (#a0, :v0)",
"ExpressionAttributeNames": {
"#a0": "email"
},
"ExpressionAttributeValues": {
":v0": {
"S": "mel"
}
},
"TableName": "user_qa",
"IndexName": "email-index"
}
I note that the actual query sent to DynamoDB does not contain KeyConditions or KeyConditionExpression, as the error message indicates. What am I doing wrong that prevents this query from being written correctly such that it executes the query against the global secondary index I've added for this table?

As it turns out, calls like .contains(text) are used as filters, not query parameters. DynamoDB can't figure out if the text in the index contains the text I'm searching for without looking at every single record, which is a scan, not a query. So it doesn't make sense to try to use .contains(text) in this context, even though it's possible to call it in a chain like the one I constructed. What I ultimately needed to do to make this work is turn my call into a table scan with the .contains(text) filter:
Users.scan({ email: { contains: query.email }}).all().exec().then( ... )

I am not familiar with Dynamoose too much but the following code below will do an update on a record using node.JS and DynamoDB. See the key parameter I have below; by the error message you got it seems you are missing this.
To my knowledge, you must specify a key for an UPDATE request. You can checks the AWS DynamoDB docs to confirm.
var params = {
TableName: table,
Key: {
"id": customerID,
},
UpdateExpression: "set customer_name= :s, customer_address= :p, customer_phone= :u, end_date = :u",
ExpressionAttributeValues: {
":s": customer_name,
":p": customer_address,
":u": customer_phone
},
ReturnValues: "UPDATED_NEW"
};
await docClient.update(params).promise();

I am not get value which is sent in request body in specific json format

I need help in my one issue. I have write the program in that I am use map in node.js.
I am testing this program using postman by sending JSON structure, however I am not get specific value in console which I am printing.
Please see below code .
async CreateProduceMVPRateAsset(data, callback) {
// Create a new file system based wallet for managing identities.
var ProducePRICE = {};
var MVPRATE = new Map();
var MVPPRICE =[];
var MVPPRICE_BS ={};
var MVPPRICE_LB ={};
var PRODUCENAME = data.PRODUCE
console.log('PRODUCENAME', PRODUCENAME);
var COUNTRY = data.COUNTRY;
console.log('COUNTRY', COUNTRY);
var STATE = data.STATE;
console.log('STATE', STATE);
MVPRATES = data.MVPRATES;
console.log('MVPRATERATE', MVPRATES); // not getting value of MVPRATES from request body
}
JSON structure which is sending using POSTMAN
{
"username": "admin2",
"PRODUCE": "Apple",
"STATE": "MI",
"COUNTRY": "US",
"MVPRATES": {
"fuji": {
"VARIETY": "fuji",
"RATE": [
{
"UNIT": "Bussel",
"CURRENCY": "USD",
"VALUE": 10.25,
"UIDISPLAY": true
}
]
},
"gala": {
"VARIETY": "gala",
"RATE": [
{
"UNIT": "Bussel",
"CURRENCY": "USD",
"VALUE": 10.25,
"UIDISPLAY": true
}
]
}
}
}
output
Any help very appreciable
Thanks
Abhijeet

That's how logs will show up for the non-primitive type of data. Try stringifying the response like:
MVPRATES = data.MVPRATES;
console.log('MVPRATERATE', JSON.stringify(MVPRATES));
This will help you in printing actual values to the logs. A better approach will be to use a logging module like winston and configure all such things and many more.

Sorry to waste you all time I think I miss the var in front of MVPRATES. It should be
var MVPRATES = data.MVPRATES;

How can I post a container in Storage api from loopback?

I already have declared my datasource ,my model and the connector between these.
My model
{
"name": "container",
"base": "Model",
"idInjection": true,
"options": {
"validateUpsert": true
},
"properties": {},
"validations": [],
"relations": {},
"acls": [],
"methods": {}
}
Datasource
"storage": {
"name": "storage",
"connector": "loopback-component-storage",
"provider": "filesystem",
"root": "./server/storage"
}
My provider
{
"filesystem": {
"root": "./server/storage"
}
}
And the Connector
"container": {
"dataSource": "storage",
"public": true
}
I try posting a object like {"Object":"container1"} into path "./server/storage" but I get the following error from callback.
{
"error": {
"statusCode": 500,
"name": "TypeError",
"message": "Path must be a string. Received undefined",
"stack": "TypeError: Path must be a string. Received undefined.."
}
}
Please who can help me to find my issue? Thanks!

You can also use "name" instead of "Object" as key in your JSON object to create a new container/directory using the API.
POST /api/containers {"name":"container1"}

The way to post a container is, without using the loopback api. Create a folder that is gonna be the container into your provider path (being filesystem).
As simple as that!

If you need a programmatic way to add new containers, let's say for example you want to create a filesystem of sorts for new users. You can use the route below. "Container" is the name I called my Model, you can call yours whatever you'd like.
POST localhost:3000/api/container
Inside the body of the post request you have to have an attribute name and the value of the name can be the new container you're creating. The Strongloop/Loopback documentation, which can be found here, is not accurate and neither is the error you get back when you try to post it with their directions.
"error": {
"statusCode": 500,
"name": "TypeError",
"message": "Path must be a string. Received undefined"
}
An excerpt of the code to send a post request to create a new container is also below.
var request = require("request");
var options = {
method: 'POST',
url: 'http://localhost:3000/api/containers',
body: { name: 'someNewContainer' },
json: true
};
request(options, function (error, response, body) {
if (error) throw new Error(error);
console.log(body);
});

Unexpected token < in JSON at position 0

If I do curl, the server returns an array of posts objects, like this:
curl http://localhost/api/posts/
[
{
"id": 7,
"target": {
"body": "This is the body",
"title": "Airbnb raising a reported $850M at a $30B valuation",
"user": {
"first_name": "ben",
"last_name": "jamin"
}
}
},
{
"id": 11,
"target": {
"body": "This is the body",
"title": "Browsing the APISSS",
"user": {
"first_name": "user",
"last_name": "two"
}
}
}
]
I tried getting this using the fetch api:
fromServer() {
console.log('fromServer')
var headers = new Headers();
headers.append('Accept', 'application/json');
let a = fetch('http://test.com/api/posts/', headers)
.then(function(response) {
if (response.status !== 200) {
console.log('There was a problem. Status Code: ' + response.status);
return;
}
response.json().then(function(data) {
console.log(data);
});
}
)
.catch(function(err) {
console.log('Fetch Error :-S', err);
});
}
But I am getting this error:
Unexpected token < in JSON at position 0
SyntaxError: Unexpected token < in JSON at position 0
How can I solve this problem? Could you please help me. Thank you.

It is clear that you have some syntax error while parsing response into json object.
Remove all the comments from server json file if any.
If it is not:
I believe the response body is not json.
You're receiving HTML (or XML) back from the server, but code is enable to parse as JSON.
Check the "Network" tab in Chrome dev tools to see contents of the server's response.
Or debug using this code: (as "Jaromanda X" said)
.then(function(response) {
console.log(response);
console.log(response.status);
console.log(response.json());
console.log(response.text());
})
.catch(function(err) {
console.log('Fetch Error :-S', err);
});

You can try adding the dataType property,just like dataType: 'html' or dataType: 'text'

Please check that your server is giving response in JSON format only. It should not be a string.
For Associative data you should start your JSON object with { not [ .
So your data should be in below format:
{
"data": [
{
"id": 7,
"target": {
"body": "This is the body",
"title": "Airbnb raising a reported $850M at a $30B valuation",
"user": {
"first_name": "ben",
"last_name": "jamin"
}
}
},
{
"id": 11,
"target": {
"body": "This is the body",
"title": "Browsing the APISSS",
"user": {
"first_name": "user",
"last_name": "two"
}
}
}
]
}
And you can get all data from response.data .
For more detail follow this link .

The wording of the error message corresponds to what you get from Google Chrome when you run JSON.parse('<...'). I know you said the server is setting Content-Type:application/json, but I am led to believe the response body is actually HTML.
"SyntaxError: Unexpected token < in JSON at position 0"
with the line console.error(this.props.url, status, err.toString()) underlined.
The err was actually thrown within jQuery, and passed to you as a variable err. The reason that line is underlined is simply because that is where you are logging it.
I would suggest that you add to your logging. Looking at the actual xhr (XMLHttpRequest) properties to learn more about the response. Try adding console.warn(xhr.responseText) and you will most likely see the HTML that is being received.
Please correct your code according to above explanation.

so, you can use with start JSON array ;
{
"array": [
{
"id": 7,
"target": {
"body": "This is the body",
"title": "Airbnb raising a reported $850M at a $30B valuation",
"user": {
"first_name": "ben",
"last_name": "jamin"
}
}
},
{
"id": 11,
"target": {
"body": "This is the body",
"title": "Browsing the APISSS",
"user": {
"first_name": "user",
"last_name": "two"
}
}
}
]
}

So the problem was this: Since I was testing it from the vagrant machine in LAN and in my hosts file I added the ip of vagrant machine as the url (test.com), the device was not able to fetch to that url. After I changed the vagrant machine to port forward and gave the original IP address of the machine, I was able to fetch the json objects. Thank you all for your help.

In my case, the port I was trying to use was already in use. I solved this issue by executing the follwing command in the command prompt in order to terminate the port.
taskkill /F /IM node.exe