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This nodejs script allows you to copy a faunadb (its collections, indexes, functions, and data) from a source to a destination. Note that the time it will take for this script to complete is completely dependent on how much data you have on your source database.
/**
* NOTES:
* - For the `domain` in configs, please refer to https://docs.fauna.com/fauna/current/api/fql/region_groups
* - For the `secret`, please make sure that it's `admin`. Refer to https://docs.fauna.com/fauna/current/security/keys?lang=javascript
* - The script retains the `Ref` of the data when it's being copied from the source to the destination, so relationships relying on this should still work out of the box.
* - The goal here is to make an exact replicate of the source, so once the script is done running, the destination should just work out of the box.
* - The script also checks if the collection, index, function or data already exists to prevent duplicates.
*/
/**
* INSTRUCTIONS on how to use:
* - The database you are copying FROM is referred to as `source`.
* - The database you are copying TO is referred to as `destination`.
*
* 1. Create a new database on a region that you want.
* 2. Create a secret key for both the source and destination, make sure their both admins.
* 3. Put corresponding values to the corresponding config constants below.
* 4. Run the script
*/
// enter values for the database you want to copy from
const sourceConfig = {
secret: '',
domain: 'db.fauna.com'
};
// enter values for the database you want to copy to
const destinationConfig = {
secret: '',
domain: 'db.us.fauna.com'
};
// no need to do anything from here unless debugging
const { Client, query } = require('faunadb');
const defaults = {
checkNewVersion: false,
scheme: 'https',
queryTimeout: 60000,
timeout: 60000
};
const source = new Client({
...defaults,
...sourceConfig
});
const destination = new Client({
...defaults,
...destinationConfig
});
// cache of the collections list for later use when copying the data
const collections = [];
async function copyCollections() {
let nextToken = null;
const dos = [];
do {
const result = await source.query(
query.Paginate(query.Collections(), { after: nextToken || [] })
);
nextToken = result.after;
result.data.map(async collection => {
// cache the collections list for later use when copying the data
collections.push(collection.id);
dos.push(
query.If(
query.Exists(query.Collection(collection.id)),
null,
query.CreateCollection({
name: collection.id,
history_days: 0
})
)
);
});
} while (nextToken);
await destination.query(query.Do(...dos));
console.log('Done copying collections');
}
async function copyIndexes() {
let nextToken = null;
const dos = [];
do {
const result = await source.query(
query.Map(
query.Paginate(query.Indexes(), { after: nextToken || [] }),
query.Lambda(['index'], query.Get(query.Var('index')))
)
);
nextToken = result.after;
result.data.map(async index => {
dos.push(
query.If(
query.Exists(query.Index(index.name)),
null,
query.CreateIndex({
name: index.name,
source: index.source,
terms: index.terms,
unique: index.unique || false,
values: index.values || null
})
)
);
});
} while (nextToken);
await destination.query(query.Do(...dos));
console.log('Done copying indexes');
}
async function copyData() {
await Promise.all(
collections.map(async collection => {
let nextToken = null;
do {
const result = await source.query(
query.Map(
query.Paginate(
query.Documents(query.Collection(collection)),
{ after: nextToken || [] }
),
query.Lambda(['ref'], query.Get(query.Var('ref')))
)
);
nextToken = result.after;
if (result.data.length) {
await destination.query(
query.Do(
...result.data.map(document => {
return query.If(
query.Exists(document.ref),
null,
query.Create(document.ref, {
data: document.data
})
);
})
)
);
}
} while (nextToken);
})
);
console.log('Done copying all data');
}
async function copyFunctions() {
let nextToken = null;
const dos = [];
do {
const result = await source.query(
query.Map(
query.Paginate(query.Functions(), {
after: nextToken || []
}),
query.Lambda(
['ref'],
query.Get(
query.Function(query.Select(['id'], query.Var('ref')))
)
)
)
);
nextToken = result.after;
result.data.map(async udf => {
dos.push(
query.If(
query.Exists(query.Function(udf.name)),
null,
query.CreateFunction({
name: udf.name,
body: udf.body
})
)
);
});
} while (nextToken);
await destination.query(query.Do(...dos));
console.log('Done copying functions');
}
(async () => {
await copyCollections();
await copyIndexes();
await Promise.all([copyData(), copyFunctions()]);
console.log('Done copying database!');
})();
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