Batch Generate Query Plans

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Prerequisites

To generate query plans, you will need the following:

• Router executable (version 0.185.0 or later)

• Router execution configuration file

• Queries folder

• Output folder

Generate the execution config using wgc:

wgc router fetch $graphname -o execution-config.json

To generate query plans locally or test subgraphs modifications before deployment, use wgc router compose.

For detailed steps, follow the first two steps outlined here: Mastering Local Development for GraphQL Federation.

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Generating query plans

In the following example, we assume the following directory structure:

./operations/query1.graphql
./operations/query2.graphql
./execution-config.json
./plans

You can generate query plans using the following command:

./router query-plan -execution-config execution-config.json -operations operations -plans plans

This command will create one file per query inside the plans folder. Each file will have the same name as the corresponding query and will contain a text representation of the query plan.

If a query is not plannable, the error message will be written inside the respective file. Files containing errors will always begin with the text:

Error:

For the given example, the output will generate two files:

plans/query1.graphql
plans/query2.graphql

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Report generation

You can use the -print-report option to generate a report in addition to the individual query plan files. The report will be saved in the plans folder as report.json and will follow this structure:

{
    "error": "[...]",
    "plans": [
        {
            "file_name": "[...]",
            "plan": "[...]"
        },
        {
            "file_name": "[...]",
            "error": "[...]"
        }
    ]
}

If you only need the report, you can add the following option to the command -print-per-file=false.

The error field on the first level will contains a value only if there is an error that is not directly related to a single plan (eg: timeout error, missing or corrupted router config).

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Fail on planning error

If you want the command to exit with an error if at least one query fails to be planned, you can use the option -fail-on-error.

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Other options

You can see all the options available launching the command without any arguments:

./router query-plan
  -concurrency int
        how many query plan run concurrently
  -execution-config string
        required, execution config file location
  -fail-fast
        stop as soon as possible if a plan fails
  -fail-on-error
        if at least one plan fails, the command exit code will be 1
  -filter string
        operation filter file location which should contain file names of operations to include
  -help
        Prints the help message
  -log-level string
        log level to use (debug, info, warning, error, panic, fatal) (default "warning")
  -max-collectors uint
        max number of concurrent data source collectors, if unset or 0, no limit will be enforced
  -operations string
        required, source operations folder location
  -plans string
        required, output plans folder location
  -print-per-file
        write a file for each query, with inside the plan or the query plan error (default true)
  -print-report
        write a report.json file, with all the query plans and errors sorted by file name
  -timeout string
        timeout (default "30s")