The analyzer restores files that buildpacks may use to optimize the build and export phases.

Prior to Platform API 0.7, the analyzer was responsible for analyzing the metadata from the cache and the previously built image, if available, to determine what layers can or cannot be reused. This information is used during the export phase in order to avoid re-uploading unchanged layers.
Starting from Platform API 0.7, the analyze phase runs before the detect phase in order to validate registry access for all images that are used during the build as early as possible. In this way it provides faster failures for end users. The other responsibilities of the analyzer were moved to the restorer.
For more information, please see this migration guide.

The lifecycle should attempt to locate a reference to the latest OCI image from a previous build that is readable and was created by the lifecycle using the same application source code. If no such reference is found, the analysis is skipped.

The lifecycle must write analysis metadata to <analyzed>, where:

• image MUST describe the <previous-image>, if accessible
• run-image MUST describe the <run-image>

Exit Codes

If the analyze phase was successful or there was any error during the process, the output will have one of the following exit codes:

Exit Code	Result
0	Success
11	Platform API incompatibility error
12	Buildpack API incompatibility error
1-10, 13-19	Generic lifecycle errors
30-39	Analysis-specific lifecycle errors

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For more information about the analyzer, see the Platform API spec.

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